View source for Jupiter

{{Short description|Fifth planet from the Sun}}
{{About|the planet|the Roman god|Jupiter (god)|other uses}}
{{Good article}}
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{{Use Oxford spelling|date=November 2024}}
{{Use mdy dates|date=November 2024}}
{{Infobox planet
| name = Jupiter
| symbol = [[File:Jupiter symbol (bold).svg|24px|class=skin-invert|♃]]
| image = Jupiter_OPAL_2024.png
| image_alt = A full disk image of Jupiter taken by NASA's Hubble Space Telescope
| caption = Jupiter in true colour,{{efn|The light filters are 658 nm, 502 nm, and 395 nm,<ref>{{cite web | title=Jupiter OPAL 2024 | year=2024 | publisher=NASA | url=https://science.nasa.gov/asset/hubble/jupiter-opal-2024/ | access-date=2025-05-10 }}</ref> roughly corresponding to red, green and blue respectively}} taken by the [[Hubble Space Telescope]] in January 2024<ref group=lower-alpha name=caption>Jupiter's atmosphere and its appearance [[Atmosphere of Jupiter#Dynamics|constantly change]], and hence its current appearance today may not resemble what it was when this image was taken. Depicted in this image, however, are a few features that remain consistent, such as the famous [[Great Red Spot]], featured prominently in the lower right of the image, and the planet's recognisable banded appearance.</ref>
| background = Wheat
| named_after = [[Jupiter (god)|Jupiter]]
| orbit_ref = <ref name="fact"/>
| epoch = [[J2000]]
| semimajor = {{Convert|778.479|e6km|AU|sigfig=5|abbr=unit|order=flip}}
| aphelion = {{Convert|816.363|e6km|AU|sigfig=5|abbr=unit|lk=on|order=flip}}
| perihelion = {{Convert|740.595|e6km|AU|sigfig=5|abbr=unit|order=flip}}
| time_periastron = January 21, 2023<ref name=horizons-perihelion>{{Cite web|url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%27599%27&START_TIME=%272023-01-01%27&STOP_TIME=%272023-01-31%27&STEP_SIZE=%273%20hours%27&QUANTITIES=%2719%27|title=HORIZONS Planet-center Batch call for January 2023 Perihelion|website=ssd.jpl.nasa.gov|type=Perihelion for Jupiter's planet-centre (599) occurs on 2023-Jan-21 at 4.9510113au during a rdot flip from negative to positive|publisher=NASA/JPL|access-date=September 7, 2021|archive-date=September 7, 2021|archive-url=https://web.archive.org/web/20210907235300/https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%27599%27&START_TIME=%272023-01-01%27&STOP_TIME=%272023-01-31%27&STEP_SIZE=%273%20hours%27&QUANTITIES=%2719%27|url-status=live}}</ref>
| eccentricity = {{val|0.0489}}
| inclination = {{plainlist|
* 1.303° to [[ecliptic]]<ref name="VSOP87"/>
* 6.09° to [[Sun]]'s [[equator]]<ref name="VSOP87"/>
* 0.32° to [[invariable plane]]<ref name=Souami_Souchay_2012/>
 }}
| asc_node = 100.464°
| arg_peri = 273.867°<ref name="VSOP87"/>
| mean_anomaly = 20.020°<ref name="VSOP87"/>
| period = {{plainlist |
* {{val|11.862|u=[[julian year (astronomy)|yr]]}}
* {{val|fmt=commas|4332.59|u=days}}
* {{val|fmt=commas|10476.8|u=Jovian [[solar day]]s}}<ref name="planet_years">{{cite web |url=http://cseligman.com/text/sky/rotationvsday.htm |title=Rotation Period and Day Length |last=Seligman |first=Courtney |access-date=August 13, 2009 |archive-date=September 29, 2018 |archive-url=https://web.archive.org/web/20180929010908/http://cseligman.com/text/sky/rotationvsday.htm |url-status=live }}</ref>
 }}
| synodic_period = {{val|398.88|u=days}}
| avg_speed = {{val|13.06|u=km/s}}
| satellites = [[moons of Jupiter|97]] ({{as of|2025|lc=y}})<ref name="jplsats-disc"/>
| physical_ref = <ref name="fact"/><ref name="Seidelmann Archinal A'hearn et al. 2007">{{cite journal |doi=10.1007/s10569-007-9072-y |last1=Seidelmann |first1=P. Kenneth |last2=Archinal |first2=Brent A. |last3=A'Hearn<!-- written A'hearn here, mostly A'Hearn elsewhere --> |first3=Michael F. |last4=Conrad |first4=Albert R. |last5=Consolmagno |first5=Guy J. |last6=Hestroffer |first6=Daniel |last7=Hilton |first7=James L. |last8=Krasinsky |first8=Georgij A. |last9=Neumann |first9=Gregory A. |last10=Oberst | first10=Jürgen |last11=Stooke |first11=Philip J. |last12=Tedesco |first12=Edward F. |last13=Tholen |first13=David J. |last14=Thomas |first14=Peter C. |last15=Williams |first15=Iwan P. |year=2007 |title=Report of the IAU/IAG Working Group on cartographic coordinates and rotational elements: 2006 |journal=Celestial Mechanics and Dynamical Astronomy |volume=98 |issue=3 |pages=155–180 |bibcode=2007CeMDA..98..155S |doi-access=free |issn=0923-2958}}</ref><ref name="PS15">{{cite book |last1=de Pater |first1=Imke |last2=Lissauer |first2=Jack J. |title=Planetary Sciences |year=2015 |url=https://books.google.com/books?id=stFpBgAAQBAJ&pg=PA250 |page=250 |publisher=Cambridge University Press |location=New York |isbn=978-0-521-85371-2 |edition=2nd updated |access-date=August 17, 2016}}</ref>
| flattening = {{val|0.06487|fmt=commas}}
| equatorial_radius = {{val|71492|u=km}}<ref group=lower-alpha name=1bar>Refers to the level of 1 bar atmospheric pressure</ref>{{plainlist|
* {{val|11.209|u=× of [[Equatorial radius|Earth's]]}}
* {{val|0.10276|u=× of [[Solar radius|Sun's]]}}
}}
| polar_radius = {{val|66854|u=km}}<ref group=lower-alpha name=1bar/><br/>{{val|10.517|u=× of Earth's}}
| mean_radius = {{val|69911|u=km}}<ref group=lower-alpha name=1bar/><br/>{{val|10.973|u=× of Earth's}}
| surface_area = {{val|6.1469|e=10|u=km2}}<br/>{{val|120.4|u=× of [[Surface area of earth|Earth's]]}}
| volume = {{val|1.4313|e=15|u=km3}}<ref group=lower-alpha name=1bar/><br/>{{val|fmt=commas|1321|u=× of [[Volume of Earth|Earth's]]}}
| mass = {{val|1.8982|e=27|u=kg}}{{plainlist|
* {{val|317.8|u=× of [[Earth mass|Earth's]]}}
* {{val|0.00095|u=× of [[Solar mass|Sun's]]}}<ref name=ssd-constants>{{cite web |title=Astrodynamic Constants |publisher=JPL Solar System Dynamics |date=February 27, 2009 |url=http://ssd.jpl.nasa.gov/?constants |access-date=August 8, 2007 |archive-date=March 21, 2019 |archive-url=https://web.archive.org/web/20190321205811/https://ssd.jpl.nasa.gov/?constants |url-status=live }}</ref>
}}
| density = {{val|1.326|u=g/cm3}}<ref group=lower-alpha name=1bar_b>Based on the volume within the level of 1 bar atmospheric pressure</ref>
| surface_grav = {{cvt|24.79|m/s2|g0|lk=on|disp=br}}<ref group=lower-alpha name=1bar/><ref name="nasafact">{{Cite web |date=June 2, 2011 |title=NASA: Solar System Exploration: Planets: Jupiter: Facts & Figures |url=http://solarsystem.nasa.gov/planets/profile.cfm?Object=Jupiter&Display=Facts |url-status=dead |archive-url=https://web.archive.org/web/20110905225941/http://solarsystem.nasa.gov/planets/profile.cfm?Object=Jupiter&Display=Facts |archive-date=September 5, 2011 |access-date=October 15, 2024 |publisher=solarsystem.nasa.gov}}</ref>
| moment_of_inertia_factor = {{val|0.2756|0.0006}}<ref name="Ni2018">{{cite journal | last=Ni | first=D. | title=Empirical models of Jupiter's interior from Juno data | journal=Astronomy & Astrophysics | volume=613 | year=2018 | page=A32 | doi=10.1051/0004-6361/201732183 | doi-access=free | bibcode=2018A&A...613A..32N }}</ref>
| escape_velocity = {{val|59.5|u=km/s}}<ref group=lower-alpha name=1bar/>
| rotation = {{val|9.9258|u=hours}} (9 h 55&nbsp;m 33 s)<ref name="planet_years"/>
| sidereal_day = 9.9250 hours (9 h 55&nbsp;m 30 s)
| rot_velocity = {{val|12.6|u=km/s|}}
| axial_tilt = 3.13° (to orbit)
| right_asc_north_pole = 268.057°; {{RA|17|52|14}}<ref name="iau2015">{{Cite journal |last1=Archinal |first1=B. A. |last2=Acton |first2=C. H. |last3=A'Hearn |first3=M. F. |last4=Conrad |first4=A. |last5=Consolmagno |first5=G. J. |last6=Duxbury |first6=T. |last7=Hestroffer |first7=D. |last8=Hilton |first8=J. L. |last9=Kirk |first9=R. L. |last10=Klioner |first10=S. A. |last11=McCarthy |first11=D. |last12=Meech |first12=K. |last13=Oberst |first13=J. |last14=Ping |first14=J. |last15=Seidelmann |first15=P. K. |date=2018 |title=Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2015 |url=http://link.springer.com/10.1007/s10569-017-9805-5 |journal=Celestial Mechanics and Dynamical Astronomy |language=en |volume=130 |issue=3 |page=22 |doi=10.1007/s10569-017-9805-5 |bibcode=2018CeMDA.130...22A |issn=0923-2958|url-access=subscription }}</ref>
| declination = 64.495°<ref name="iau2015"/>
| albedo = {{ubl| 0.503 ([[Bond albedo|Bond]])<ref name="Li_et_al"/> | 0.538 ([[Geometric albedo|geometric]])<ref name="Mallama_et_al"/>}}
| magnitude = −2.94<ref name="Mallama_and_Hilton"/> to −1.66<ref name="Mallama_and_Hilton"/>
| abs_magnitude = −9.4<ref name="IMCCE">{{cite web | title=Encyclopedia - the brightest bodies | website=IMCCE | url=https://promenade.imcce.fr/en/pages5/572.html | access-date=May 29, 2023 | archive-date=July 24, 2023 | archive-url=https://web.archive.org/web/20230724225002/https://promenade.imcce.fr/en/pages5/572.html | url-status=live }}</ref>
| angular_size = 29.8" to 50.1"
| pronounced = {{IPAc-en|audio=en-us-Jupiter.ogg|ˈ|dʒ|uː|p|ᵻ|t|ər}}<ref>{{cite dictionary |title=Jupiter |dictionary=[[Oxford English Dictionary]] |publisher=Clarendon |first1=J. A. |last1=Simpson |first2=E. S. C. |last2=Weiner |edition=2nd |volume=8 |year=1989 |isbn=978-0-19-861220-9 |url=https://archive.org/details/oxfordenglishdic00_0 }}</ref>
| adjectives = [[wikt:Jovian|Jovian]] ({{IPAc-en|ˈ|dʒ|oʊ|v|i|ə|n}})
| single_temperature = {{cvt|88|K|C|0}} ([[Effective temperature|blackbody temperature]])
| temp_name1 = 1 [[bar (unit)|bar]]
| min_temp_1 = 
| mean_temp_1 = 165 [[Kelvin|K]]
| max_temp_1 = 
| temp_name2 = 0.1 bar
| min_temp_2 = 78 K
| mean_temp_2 = 128 K
| max_temp_2 = 
| atmosphere = yes
| atmosphere_ref = <ref name="fact"/>
| surface_pressure = {{convert|200-600|kPa|abbr=unit|sigfig=1}}<br/>(opaque cloud deck)<ref>{{cite journal | title=Jupiter's Deep Cloud Structure Revealed Using Keck Observations of Spectrally Resolved Line Shapes | last1=Bjoraker | first1=G. L. | last2=Wong | first2=M. H. | last3=de Pater | first3=I. | last4=Ádámkovics | first4=M. | journal=The Astrophysical Journal | volume=810 | issue=2 | id=122 | pages=10 | date=September 2015 | doi=10.1088/0004-637X/810/2/122 | arxiv=1508.04795 | bibcode=2015ApJ...810..122B | s2cid=55592285 }}</ref>
| scale_height = {{convert|27|km|mi|abbr=unit}}
| atmosphere_composition = {{Unbulleted indent list
| {{val|89|2.0|u=%}} [[hydrogen]]
| {{val|10|2.0|u=%}} [[helium]]
| {{val|0.3|0.1|u=%}} [[methane]]
| {{val|0.026|0.004|u=%}} [[ammonia]]
| {{val|0.0028|0.001|u=%}} [[hydrogen deuteride]]
| {{val|0.0006|0.0002|u=%}} [[ethane]]
| {{val|0.0004|0.0004|u=%}} [[water]]
}}
}}

'''Jupiter''' is the fifth [[planet]] from the [[Sun]] and the [[List of Solar System objects by size|largest in the Solar System]]. It is a [[gas giant]] with a [[Jupiter mass|mass]] more than 2.5 times that of all the other planets in the [[Solar System]] combined and slightly less than one-thousandth the mass of the Sun. Its diameter is 11 times that of [[Earth]] and a tenth that of the Sun. Jupiter orbits the Sun at a distance of {{Convert|778.479|Gm|AU|lk=on|adj=ri1|sigfig=3|abbr=unit|order=flip}}, with an [[orbital period]] of {{val|11.86|u=[[julian year (astronomy)|years]]}}. It is the [[List of brightest natural objects in the sky|third-brightest natural object]]<!-- artificial satellites can be much brighter (e.g., iridium flares) --> in the Earth's [[night sky]], after the [[Moon]] and [[Venus]], and has been observed since [[prehistoric times]]. Its name derives from that of [[Jupiter (god)|Jupiter]], the chief deity of [[ancient Roman religion]].

Jupiter was the first of the Sun's planets to form, and its inward migration during the primordial phase of the Solar System affected much of the formation history of the other planets. [[Jupiter's atmosphere]] consists of 76% [[hydrogen]] and 24% [[helium]] by mass, with a denser interior. It contains trace elements and compounds like [[carbon]], [[oxygen]], [[sulfur]], [[neon]], [[ammonia]], [[water vapour]], [[phosphine]], [[hydrogen sulfide]], and [[hydrocarbon]]s. Jupiter's helium abundance is 80% of the Sun's, similar to [[Saturn]]'s composition.

The outer atmosphere is divided into a series of latitudinal bands, with turbulence and storms along their interacting boundaries; the most obvious result of this is the [[Great Red Spot]], a giant storm that has been recorded since 1831. Because of its rapid rotation rate, one turn in ten hours, Jupiter is an [[oblate spheroid]]; it has a slight but noticeable 6.5%{{Efn|1=100 x (equatorial radius- polar radius)/(equatorial radius) = 100 x (71492-66854)/71492 = 6.487%.}} bulge around the equator compared to its poles. Its internal structure is believed to consist of an outer mantle of fluid [[metallic hydrogen]] and a diffuse inner core of denser material. The ongoing contraction of Jupiter's interior generates more heat than the planet receives from the Sun. Jupiter's [[magnetic field]] is the strongest and second-largest contiguous structure in the Solar System, generated by [[eddy current]]s within the fluid, metallic hydrogen core. The [[solar wind]] interacts with the [[magnetosphere]], extending it outward and affecting Jupiter's orbit.

At least [[Moons of Jupiter|97 moons]] orbit the planet; the [[Galilean moons|four largest moons]]—[[Io (moon)|Io]], [[Europa (moon)|Europa]], [[Ganymede (moon)|Ganymede]], and [[Callisto (moon)|Callisto]]—orbit within the magnetosphere and are visible with common binoculars. Ganymede, the largest of the four, is larger than the planet [[Mercury (planet)|Mercury]]. Jupiter is surrounded by a faint system of [[planetary ring]]s. The [[rings of Jupiter]] consist mainly of dust and have three main segments: an inner [[torus]] of particles known as the halo, a relatively bright main ring, and an outer gossamer ring. The rings have a reddish colour in visible and near-infrared light. The age of the ring system is unknown, possibly dating back to Jupiter's formation.

In 1610 [[Galileo Galilei]] published the first telescopic study of Jupiter. Since 1973, Jupiter has been [[List of missions to the outer planets|visited by]] nine [[robotic spacecraft|robotic probes]]: seven [[Flyby (spaceflight)|flybys]] and two dedicated orbiters, with two more en route. [[Jupiter analogue|Jupiter-like exoplanets]] have also been found in other solar systems.

== Name and symbol ==
In both the ancient Greek and Roman civilizations, Jupiter was named after the chief god of the divine [[Pantheon (religion)|pantheon]]: [[Zeus]] to the Greeks and [[Jupiter (god)|Jupiter]] to the Romans.<ref>{{cite book |last=Alexander |first=Rachel |title=Myths, Symbols and Legends of Solar System Bodies |publisher=Springer |year=2015 |isbn=978-1-4614-7066-3 |series=The Patrick Moore Practical Astronomy Series |volume=177 |location=New York, NY |pages=141–159 |bibcode=2015msls.book.....A |doi=10.1007/978-1-4614-7067-0}}</ref> The [[International Astronomical Union]] formally adopted the name Jupiter for the planet in 1976 and has since named its newly discovered satellites for the god's lovers, favourites, and descendants.<ref>{{cite web |title=Naming of Astronomical Objects | publisher=International Astronomical Union | url=https://www.iau.org/public/themes/naming/ | access-date=March 23, 2022 | archive-date=October 31, 2013 | archive-url=https://web.archive.org/web/20131031154417/https://www.iau.org/public/themes/naming/ | url-status=deviated }}</ref> The [[planetary symbol]] for Jupiter, [[File:Jupiter symbol (fixed width).svg|16px|♃]], descends from a Greek [[zeta]] with a [[Scribal abbreviation#Forms|horizontal stroke]], {{angbr|Ƶ}}, as an abbreviation for ''Zeus''.<ref name=jones-1999>{{cite book| title = Astronomical papyri from Oxyrhynchus| last = Jones| first = Alexander| date = 1999| pages = 62–63| publisher = American Philosophical Society| isbn = 978-0-87169-233-7| url = https://books.google.com/books?id=8MokzymQ43IC| quote = It is now possible to trace the medieval symbols for at least four of the five planets to forms that occur in some of the latest papyrus horoscopes ([ [[Oxyrhynchus Papyri|P.Oxy.]] ] 4272, 4274, 4275 [...]). That for Jupiter is an obvious monogram derived from the initial letter of the Greek name.}}</ref><ref>{{cite journal| title=The origin of the symbols of the planets| last=Maunder | first=A. S. D. | author-link=Annie S. D. Maunder| journal=The Observatory| volume=57 | pages=238–247| date=August 1934 | bibcode=1934Obs....57..238M }}</ref>

In Latin, ''Iovis'' is the [[genitive case]] of ''[[Iuppiter]]'', i.e. Jupiter. It is associated with the etymology of ''Zeus'' ('sky father'). The English equivalent, ''Jove'', is known to have come into use as a poetic name for the planet around the 14th century.<ref>{{cite web | title=Jove | first=Douglas | last=Harper | work=Online Etymology Dictionary | url=https://www.etymonline.com/word/jove | access-date=March 22, 2022 | archive-date=March 23, 2022 | archive-url=https://web.archive.org/web/20220323021235/https://www.etymonline.com/word/jove | url-status=live }}</ref>

'''Jovian''' is the [[Adjective|adjectival]] form of Jupiter. The older adjectival form ''jovial'', employed by astrologers in the [[Middle Ages]], has come to mean 'happy' or 'merry', moods ascribed to Jupiter's influence in [[Jupiter (astrology)|astrology]].<ref>{{cite web |title=Jovial |url=http://dictionary.reference.com/browse/jovial |access-date=July 29, 2007 |work=Dictionary.com |archive-date=February 16, 2012 |archive-url=https://web.archive.org/web/20120216090837/http://dictionary.reference.com/browse/jovial |url-status=live }}</ref>

The original Greek deity ''Zeus'' supplies the root ''zeno-'', which is used to form some Jupiter-related words, such as ''[[wikt:zenography|zenography]]''.{{refn |group=lower-alpha |See for example: {{cite news |title=IAUC 2844: Jupiter; 1975h |publisher=International Astronomical Union |date=October 1, 1975 |url=http://cbat.eps.harvard.edu/iauc/02800/02844.html |access-date=October 24, 2010}} That particular word has been in use since at least 1966. See: {{cite web |url=http://adsabs.harvard.edu/cgi-bin/nph-abs_connect?db_key=AST&text=zenographic%20since%20at%20least%201966 |title=Query Results from the Astronomy Database |publisher=Smithsonian/NASA |access-date=July 29, 2007}}}}

== Formation and migration ==
{{Main|Grand tack hypothesis}}
{{See also|Formation and evolution of the Solar System}}
Jupiter is believed to be the oldest planet in the Solar System, having formed just one million years after the Sun and roughly 50 million years before Earth.<ref name="Kruijer_et_al_2017"/> Current models of Solar System formation suggest that Jupiter formed at or beyond the [[Frost line (astrophysics)|snow line]]: a distance from the early Sun where the temperature was sufficiently cold for [[Volatile (astrogeology)|volatiles]] such as water to condense into solids.<ref name="Bosman_et_al_2019"/> First forming a solid core, the planet then accumulated its [[Primary atmosphere|gaseous atmosphere]]. Therefore, the planet must have formed before the solar nebula was fully dispersed.<ref name="dangelo2021"/> During its formation, Jupiter's mass gradually increased until it had 20 times the mass of the Earth, approximately half of which was made up of silicates, ices and other heavy-element constituents.<ref name=Kruijer_et_al_2017/> When the proto-Jupiter grew larger than 50 Earth masses it created a gap in the solar nebula.<ref name=Kruijer_et_al_2017/> Thereafter, the growing planet reached its final mass in 3–4{{Nbsp}}million years.<ref name=Kruijer_et_al_2017>{{cite journal | title=Age of Jupiter inferred from the distinct genetics and formation times of meteorites | last1=Kruijer | first1=Thomas S. | last2=Burkhardt | first2=Christoph | last3=Budde | first3=Gerrit | last4=Kleine | first4=Thorsten | journal=Proceedings of the National Academy of Sciences | volume=114 | issue=26 | pages=6712–6716 | date=June 2017 | doi=10.1073/pnas.1704461114 | pmid=28607079 | pmc=5495263 | bibcode=2017PNAS..114.6712K | doi-access=free }}</ref><ref name="dangelo2021"/> Since Jupiter is made of the same elements as the Sun (hydrogen and helium) it has been suggested that the [[Solar System]] might have been a [[star system|system of multiple protostars]] early in [[Formation and evolution of the Solar System|its formation]], with Jupiter being the second but failed protostar. But the Solar System never developed into a system of multiple stars and Jupiter does not qualify as a [[protostar]] or [[brown dwarf]] since it does not have enough mass to fuse hydrogen.<ref>{{Cite journal |last1=Bodenheimer |first1=Peter |last2=D'Angelo |first2=Gennaro |last3=Lissauer |first3=Jack J. |last4=Fortney |first4=Jonathan J. |last5=Saumon |first5=Didier |date=June 3, 2013 |title=Deuterium Burning In Massive Giant Planets And Low-mass Brown Dwarfs Formed By Core-nucleated Accretion |url=https://iopscience.iop.org/article/10.1088/0004-637X/770/2/120 |journal=The Astrophysical Journal |volume=770 |issue=2 |pages=120 |doi=10.1088/0004-637X/770/2/120 |arxiv=1305.0980 |bibcode=2013ApJ...770..120B |issn=0004-637X}}</ref><ref name="DROBYSHEVSKI 1974 pp. 35–36">{{cite journal | last=Drobyshevski | first=E. M. | title=Was Jupiter the protosun's core? | journal=Nature | publisher=Springer Science and Business Media LLC | volume=250 | issue=5461 | year=1974 | issn=0028-0836 | doi=10.1038/250035a0 | pages=35–36| bibcode=1974Natur.250...35D | s2cid=4290185 }}</ref>

According to the "[[grand tack hypothesis]]", Jupiter began to form at a distance of roughly {{Convert|3.5|AU|e6km e6mi|lk=on|abbr=unit}} from the Sun. As the young planet [[Accretion (astrophysics)|accreted]] mass, its interaction with the gas disk orbiting the Sun and the [[orbital resonance]]s from [[Saturn]] caused it to migrate inwards.<ref name=Bosman_et_al_2019>{{cite journal| title=Jupiter formed as a pebble pile around the N2 ice line| last1=Bosman | first1=A. D. | last2=Cridland | first2=A. J. | last3=Miguel | first3=Y.| journal=Astronomy & Astrophysics| volume=632 | id=L11 | pages=5 | date=December 2019| arxiv=1911.11154 | bibcode=2019A&A...632L..11B | doi=10.1051/0004-6361/201936827 | s2cid=208291392}}</ref><ref name="Walsh_etal_2011">{{cite journal | last1=Walsh| first1=K. J.| last2=Morbidelli| first2=A.| last3=Raymond| first3=S. N.| last4=O'Brien| first4=D. P.| last5=Mandell| first5=A. M.| year=2011| title=A low mass for Mars from Jupiter's early gas-driven migration| journal=[[Nature (journal)|Nature]]| volume=475| issue=7355| pages=206–209| doi=10.1038/nature10201| bibcode=2011Natur.475..206W| arxiv=1201.5177| pmid=21642961| s2cid=4431823}}</ref> This upset the orbits of several [[super-Earth]]s orbiting closer to the Sun, causing them to collide destructively.<ref name=tack/> Saturn would later have begun to migrate inwards at a faster rate than Jupiter until the two planets became captured in a 3:2 [[mean motion resonance]] at approximately {{Convert|1.5|AU|e6km e6mi|abbr=unit}} from the Sun.<ref>{{cite journal |last1=Chametla |first1=Raúl O |last2=D'Angelo |first2=Gennaro |last3=Reyes-Ruiz |first3=Mauricio |last4=Sánchez-Salcedo |first4=F Javier |date=March 2020 |title=Capture and migration of Jupiter and Saturn in mean motion resonance in a gaseous protoplanetary disc |journal=Monthly Notices of the Royal Astronomical Society |volume=492 |issue=4 |pages=6007–6018 |arxiv=2001.09235 |doi=10.1093/mnras/staa260 |doi-access=free}}</ref> This changed the direction of migration, causing them to migrate away from the Sun and out of the inner system to their current locations.<ref name=tack>{{cite journal |title=Jupiter's decisive role in the inner Solar System's early evolution |first=Konstantin |last=Batygin |doi=10.1073/pnas.1423252112 |pmid=25831540 |pmc=4394287 |volume=112 |issue=14 |pages=4214–4217 |journal=Proceedings of the National Academy of Sciences |arxiv=1503.06945 |bibcode=2015PNAS..112.4214B|year=2015 |author-link=Konstantin Batygin |doi-access=free }}</ref> All of this happened over a period of 3–6{{Nbsp}}million years, with the final migration of Jupiter occurring over several hundred thousand years.<ref name="Walsh_etal_2011"/><ref>{{cite journal
| last1=Haisch Jr.
| first1=K. E.
| last2=Lada
| first2=E. A.
| last3=Lada
| first3=C. J.
| title=Disc Frequencies and Lifetimes in Young Clusters
| year=2001
| journal=The Astrophysical Journal
| volume=553
| issue=2
| pages=153–156| doi=10.1086/320685
| arxiv=astro-ph/0104347
| bibcode=2001ApJ...553L.153H
| s2cid=16480998
| url=https://cds.cern.ch/record/496876
}}</ref> Jupiter's migration from the inner Solar System eventually allowed the inner planets—including Earth—to form from the rubble.<ref>{{cite web
|url=https://www.nationalgeographic.com/science/article/150324-jupiter-super-earth-collisions-planets-astronomy-sky-watching
|archive-url=https://web.archive.org/web/20170314171306/http://news.nationalgeographic.com/2015/03/150324-jupiter-super-earth-collisions-planets-astronomy-sky-watching/
|archive-date=March 14, 2017
|title=Observe: Jupiter, Wrecking Ball of Early Solar System
|last=Fazekas
|first=Andrew
|date=March 24, 2015
|work=National Geographic
|access-date=April 18, 2021
|url-status=dead}}</ref>

There are several unresolved issues with the grand tack hypothesis. The resulting formation timescales of terrestrial planets appear to be inconsistent with the measured elemental composition.<ref name="zube_2019">{{cite journal | last1=Zube | first1=N. | last2=Nimmo | first2=F. | last3=Fischer | first3=R.| last4=Jacobson | first4=S.|title=Constraints on terrestrial planet formation timescales and equilibration processes in the Grand Tack scenario from Hf-W isotopic evolution|journal=Earth and Planetary Science Letters|year=2019|volume=522|issue=1|pages=210–218|doi=10.1016/j.epsl.2019.07.001 |pmid=32636530|pmc=7339907|arxiv = 1910.00645 |bibcode = 2019E&PSL.522..210Z |s2cid=199100280}}</ref> Jupiter would likely have settled into an orbit much closer to the Sun if it had migrated through the [[solar nebula]].<ref name="dangelo_marzari_2012">{{cite journal | last1=D'Angelo | first1=G. | last2=Marzari | first2=F. |title=Outward Migration of Jupiter and Saturn in Evolved Gaseous Disks|journal=The Astrophysical Journal|year=2012|volume=757|issue=1|page=50 (23 pp.)|doi=10.1088/0004-637X/757/1/50 |arxiv = 1207.2737 |bibcode = 2012ApJ...757...50D |s2cid=118587166}}</ref> Some competing models of Solar System formation predict the formation of Jupiter with orbital properties that are close to those of the present-day planet.<ref name=dangelo2021>{{cite journal | last1=D'Angelo | first1=G. | last2=Weidenschilling | first2=S. J. | last3=Lissauer | first3=J. J. | last4=Bodenheimer | first4=P. | title=Growth of Jupiter: Formation in disks of gas and solids and evolution to the present epoch | journal=Icarus |year=2021 | volume=355 | page=114087 | arxiv=2009.05575 | doi=10.1016/j.icarus.2020.114087 | bibcode=2021Icar..35514087D | s2cid=221654962 }}</ref> Other models predict Jupiter forming at distances much further out, such as {{Convert|18|AU|e9km e9mi|abbr=unit}}.<ref name=Pirani_et_al_2019>{{cite journal | title=Consequences of planetary migration on the minor bodies of the early solar system | last1=Pirani | first1=S. | last2=Johansen | first2=A. | last3=Bitsch | first3=B. | last4=Mustill | first4=A.J. | last5=Turrini | first5=D. | journal=Astronomy & Astrophysics | volume=623 | date=March 2019 | pages=A169 | doi=10.1051/0004-6361/201833713| arxiv=1902.04591 | bibcode=2019A&A...623A.169P | doi-access=free }}</ref><ref name=Pirani_accompanying_article>{{cite web |url=https://www.sciencedaily.com/releases/2019/03/190322105706.htm |title=Jupiter's Unknown Journey Revealed |work=ScienceDaily |publisher=Lund University |date=March 22, 2019 |access-date=March 25, 2019 |archive-date=March 22, 2019 |archive-url=https://web.archive.org/web/20190322165523/https://www.sciencedaily.com/releases/2019/03/190322105706.htm |url-status=live }}</ref>

According to the [[Nice model]], the infall of proto-[[Kuiper belt]] objects over the first 600 million years of Solar System history caused Jupiter and Saturn to migrate from their initial positions into a 1:2 resonance, which caused Saturn to shift into a higher orbit, disrupting the orbits of Uranus and Neptune, depleting the Kuiper belt, and triggering the [[Late Heavy Bombardment]].<ref name="Levison2008">{{cite journal |last1=Levison |first1=Harold F. |last2=Morbidelli |first2=Alessandro |last3=Van Laerhoven |first3=Christa |last4=Gomes |first4=R. |date=2008 |title=Origin of the structure of the Kuiper belt during a dynamical instability in the orbits of Uranus and Neptune |journal=[[Icarus (journal)|Icarus]] |volume=196 |issue=1 |pages=258–273 |arxiv=0712.0553 |bibcode=2008Icar..196..258L |doi=10.1016/j.icarus.2007.11.035|s2cid=7035885 }}</ref>

According to the [[Jumping-Jupiter scenario]], Jupiter's migration through the early Solar System could have led to the ejection of a [[Fifth Giant|fifth gas giant]]. This hypothesis suggests that during its orbital migration, Jupiter's gravitational influence disrupted the orbits of other gas giants, potentially casting one planet out of the Solar System entirely. The dynamics of such an event would have dramatically altered the formation and configuration of the Solar System, leaving behind only the four gas giants humans observe today.<ref>{{Cite journal |title=Evidence for a Distant Giant Planet in the Solar System |doi=10.3847/0004-6256/151/2/22 |doi-access=free |date=2016 |last1=Batygin |first1=Konstantin |last2=Brown |first2=Michael E. |journal=The Astronomical Journal |volume=151 |issue=2 |page=22 |arxiv=1601.05438 |bibcode=2016AJ....151...22B }}</ref>

Based on Jupiter's composition, researchers have made the case for an initial formation outside the [[molecular nitrogen]] (N<sub>2</sub>) snow line, which is estimated at {{Convert|20|-|30|AU|e9km e9mi|abbr=unit}} from the Sun, and possibly even outside the argon snow line, which may be as far as {{Convert|40|AU|e9km e9mi|abbr=unit}}.<ref name=n2_snowline_2019>{{cite journal | last1=Öberg | first1=K.I. | last2=Wordsworth | first2=R. | title=Jupiter's Composition Suggests its Core Assembled Exterior to the N_{2} Snowline | journal=The Astronomical Journal | year=2019 | volume=158 | issue=5 | doi=10.3847/1538-3881/ab46a8 | arxiv=1909.11246 | s2cid=202749962 | doi-access=free }}</ref><ref>{{cite journal | last1=Öberg | first1=K.I. | last2=Wordsworth | first2=R. | title=Erratum: "Jupiter's Composition Suggests Its Core Assembled Exterior to the N2 Snowline" | journal=The Astronomical Journal | year=2020| volume=159 | issue=2 | page=78 | doi=10.3847/1538-3881/ab6172 | s2cid=214576608 | doi-access=free }}</ref> Having formed at one of these extreme distances, Jupiter would then have, over a roughly 700,000-year period, migrated inwards to its current location,<ref name="Pirani_et_al_2019"/><ref name="Pirani_accompanying_article"/> during an epoch approximately 2–3&nbsp;million years after the planet began to form. In this model, Saturn, Uranus, and Neptune would have formed even further out than Jupiter, and Saturn would also have migrated inwards.<ref name=Pirani_et_al_2019/>

== Physical characteristics ==
Jupiter is a [[gas giant]], meaning its chemical composition is primarily hydrogen and helium. These materials are classified as ''gasses'' in planetary geology, a term that does not denote the state of matter. It is the largest planet in the Solar System, with a diameter of {{cvt|142984|km|0}} at its [[equator]], giving it a volume 1,321 times that of the Earth.<ref name="fact"/><ref>{{cite book|page=419|title=Regents Exams and Answers: Earth Science—Physical Setting 2020|last1=Denecke|first1=Edward J.|date=January 7, 2020|publisher=Barrons Educational Series|isbn=978-1-5062-5399-2}}</ref> Its average density, 1.326&nbsp;g/cm<sup>3</sup>,{{refn |group=lower-alpha |About the same as [[Inverted sugar syrup|sugar syrup]] (syrup [[United States Pharmacopeia|USP]]),<ref name=Swarbrick2013>{{cite book | title=Encyclopedia of Pharmaceutical Technology | first=James | last=Swarbrick | date=2013 | page=3601 | volume=6 | isbn=978-1-4398-0823-8 | publisher=CRC Press | url=https://books.google.com/books?id=w2C1DwAAQBAJ&pg=PA3601 | quote="Syrup USP (1.31&nbsp;g/cm<sup>3</sup>)" | access-date=March 19, 2023 | archive-date=March 26, 2023 | archive-url=https://web.archive.org/web/20230326164802/https://books.google.com/books?id=w2C1DwAAQBAJ&pg=PA3601 | url-status=live }}</ref>}} is lower than those of the four [[terrestrial planet]]s.<ref>{{cite book | title=Allen's Astrophysical Quantities | last1=Allen | first1=Clabon Walter | author-link1=Clabon Allen | last2=Cox | first2=Arthur N. | publisher=Springer | date=2000 | pages=295–296 | isbn=978-0-387-98746-0 | url=https://books.google.com/books?id=w8PK2XFLLH8C&pg=PA296 | access-date=March 18, 2022 | archive-date=February 21, 2023 | archive-url=https://web.archive.org/web/20230221195213/https://books.google.com/books?id=w8PK2XFLLH8C&pg=PA296 | url-status=live }}</ref><ref>{{cite book | page=1041 | title=A Concise Handbook of Mathematics, Physics, and Engineering Sciences | last1=Polyanin | first1=Andrei D. | last2=Chernoutsan | first2=Alexei | date=October 18, 2010 | publisher=CRC Press | isbn=978-1-4398-0640-1 }}</ref>

=== Composition ===
The [[atmosphere of Jupiter]] is approximately 76% hydrogen and 24% helium by mass. By volume, the upper atmosphere is about 90% hydrogen and 10% helium, with the lower proportion owing to the individual helium atoms being more massive than the molecules of hydrogen formed in this part of the atmosphere.<ref>{{cite journal| title=NOTE: New Constraints on the Composition of Jupiter from Galileo Measurements and Interior Models | last1=Guillot | first1=Tristan | last2=Gautier | first2=Daniel | last3=Hubbard | first3=William B. |journal=Icarus | volume=130 | issue=2 | pages=534–539 | date=December 1997 | doi=10.1006/icar.1997.5812 | arxiv=astro-ph/9707210 | bibcode=1997Icar..130..534G
| s2cid=5466469 }}</ref> The atmosphere contains trace amounts of elemental [[carbon]], [[oxygen]], [[sulfur]], and [[neon]],<ref>{{cite book|title=Jupiter: The Planet, Satellites and Magnetosphere |editor-first=Fran |editor-last=Bagenal |editor-first2=Timothy E. |editor-last2=Dowling |editor-first3=William B. |editor-last3=McKinnon |publisher=Cambridge University Press |year=2006 |isbn=0521035457 |pages=59–75}}</ref> as well as [[ammonia]], [[water vapour]], [[phosphine]], [[hydrogen sulfide]], and [[hydrocarbons]] like [[methane]], [[ethane]] and [[benzene]].<ref>{{cite journal |journal=Icarus |volume=64 |issue=2 |pages=233–248 |year=1985 |title=Infrared Polar Brightening on Jupiter III. Spectrometry from the Voyager 1 IRIS Experiment |bibcode=1985Icar...64..233K | last1=Kim | first1=S. J. | last2=Caldwell | first2=J. | last3=Rivolo | first3=A. R. | last4=Wagner | first4=R. |doi=10.1016/0019-1035(85)90201-5}}</ref> Its outermost layer contains [[crystal]]s of frozen ammonia.<ref>{{cite journal|title=Zonal Features in the Behavior of Weak Molecular Absorption Bands on Jupiter|first1=V. D. |last1=Vdovichenko |first2=A. M. |last2=Karimov |first3=G. A. |last3=Kirienko |first4=P. G. |last4=Lysenko |first5=V. G. |last5=Tejfel’ |first6=V. A. |last6=Filippov |first7=G. A. |last7=Kharitonova |first8=A. P. |last8=Khozhenets |journal=Solar System Research |volume=55 |pages=35–46 |year=2021 |issue=1 |doi=10.1134/S003809462101010X |bibcode=2021SoSyR..55...35V |s2cid=255069821 }}</ref> The planet's interior is denser, with a composition of roughly 71% hydrogen, 24% helium, and 5% other elements by mass.<ref name="voyager">{{cite journal | last1=Gautier | first1=D. | last2=Conrath | first2=B. | last3=Flasar | first3=M. | last4=Hanel | first4=R. | last5=Kunde | first5=V. | last6=Chedin | first6=A. | last7=Scott | first7=N. |title=The helium abundance of Jupiter from Voyager |journal=Journal of Geophysical Research |volume=86 |issue=A10 |pages=8713–8720 |year=1981 |bibcode=1981JGR....86.8713G |doi=10.1029/JA086iA10p08713|hdl=2060/19810016480 |s2cid=122314894 |hdl-access=free }}</ref><ref name="cassini">{{cite journal | last1=Kunde | first1=V. G. | last2=Flasar | first2=F. M. | last3=Jennings | first3=D. E. | last4=Bézard | first4=B. | last5=Strobel | first5=D. F. | last6=Conrath | first6=B. J. | last7=Nixon | first7=C. A. | last8=Bjoraker | first8=G. L. | last9=Romani | first9=P. N. | last10=Achterberg | first10=R. K. | last11=Simon-Miller | first11=A. A. | last12=Irwin | first12=P. | last13=Brasunas | first13=J. C. | last14=Pearl | first14=J. C. | last15=Smith | first15=M. D. | last16=Orton | first16=G. S. | last17=Gierasch | first17=P. J. | last18=Spilker | first18=L. J. | last19=Carlson | first19=R. C. | last20=Mamoutkine | first20=A. A. | last21=Calcutt | first21=S. B. | last22=Read | first22=P. L. | last23=Taylor | first23=F. W. | last24=Fouchet | first24=T. | last25=Parrish | first25=P. | last26=Barucci | first26=A. | last27=Courtin | first27=R. | last28=Coustenis | first28=A. | last29=Gautier | first29=D. | last30=Lellouch | first30=E. | last31=Marten | first31=A. | last32=Prangé | first32=R. | last33=Biraud | first33=Y. | last34=Ferrari | first34=C. | last35=Owen | first35=T. C. | last36=Abbas | first36=M. M. | last37=Samuelson | first37=R. E. | last38=Raulin | first38=F. | last39=Ade | first39=P. | last40=Césarsky | first40=C. J. | last41=Grossman | first41=K. U. | last42=Coradini | first42=A. | display-authors=5 | title=Jupiter's Atmospheric Composition from the Cassini Thermal Infrared Spectroscopy Experiment | journal=Science | date=September 10, 2004 | volume=305 | issue=5690 | pages=1582–1586 | doi=10.1126/science.1100240 | pmid=15319491 | bibcode=2004Sci...305.1582K | s2cid=45296656 | doi-access=free }}</ref>

The atmospheric proportions of hydrogen and helium are close to the theoretical composition of the primordial [[solar nebula]].<ref>{{cite web|title=Solar Nebula Supermarket|date=December 2017 |publisher=nasa.gov|url=https://solarsystem.nasa.gov/genesismission/educate/scimodule/PlanetaryDiversity/plandiv_pdf/SupermarketST.pdf|access-date=July 10, 2023|archive-date=July 17, 2023|archive-url=https://web.archive.org/web/20230717222001/https://solarsystem.nasa.gov/genesismission/educate/scimodule/PlanetaryDiversity/plandiv_pdf/SupermarketST.pdf|url-status=live}}</ref> Neon in the upper atmosphere consists of 20 parts per million by mass, which is about a tenth as abundant as in the Sun.<ref>{{cite journal | last1=Niemann | first1=H. B. | last2=Atreya | first2=S. K. |  last3=Carignan | first3=G. R. | last4=Donahue | first4=T. M. | last5=Haberman | first5=J. A. | last6=Harpold | first6=D. N. | last7=Hartle | first7=R. E. | last8=Hunten | first8=D. M. | last9=Kasprzak | first9=W. T. | last10=Mahaffy | first10=P. R. | last11=Owen | first11=T. C. | last12=Spencer | first12=N. W. | last13=Way | first13=S. H. | display-authors=5 | title=The Galileo Probe Mass Spectrometer: Composition of Jupiter's Atmosphere | journal=Science | year=1996 | volume=272 | issue=5263 | pages=846–849 | bibcode=1996Sci...272..846N | doi=10.1126/science.272.5263.846 | pmid=8629016| s2cid=3242002 }}</ref> Jupiter's helium abundance is about 80% that of the Sun due to the [[Precipitation (meteorology)|precipitation]] of these elements as helium-rich droplets, a process that happens deep in the planet's interior.<ref name="galileo_ms">{{cite journal |first1=U. |last1=von Zahn |first2=D. M. |last2=Hunten |first3=G. |last3=Lehmacher |title=Helium in Jupiter's atmosphere: Results from the Galileo probe Helium Interferometer Experiment |journal=Journal of Geophysical Research |year=1998 |volume=103 |issue=E10 |pages=22815–22829 |doi=10.1029/98JE00695 |bibcode=1998JGR...10322815V |doi-access=free }}</ref><ref name="Juno">{{cite journal |title=Jupiter's Interior as Revealed by Juno |last=Stevenson |first=David J. |journal=Annual Review of Earth and Planetary Sciences |volume=48 |pages=465–489 |date=May 2020 |doi=10.1146/annurev-earth-081619-052855 |bibcode=2020AREPS..48..465S |s2cid=212832169 |doi-access=free }}</ref>

Based on [[spectroscopy]], [[Saturn]] is thought to be similar in composition to Jupiter, but the other giant planets [[Uranus]] and [[Neptune]] have relatively less hydrogen and helium and relatively more of the next [[Abundance of the chemical elements|most common elements]], including oxygen, carbon, nitrogen, and sulfur.<ref>{{cite web | last1=Ingersoll | first1=A. P. | last2=Hammel | first2=H. B. | last3=Spilker | first3=T. R. | last4=Young | first4=R. E. | date=June 1, 2005 | url=http://www.lpi.usra.edu/opag/outer_planets.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.lpi.usra.edu/opag/outer_planets.pdf |archive-date=October 9, 2022 |url-status=live | title=Outer Planets: The Ice Giants | publisher=Lunar & Planetary Institute | access-date=February 1, 2007 }}</ref> These planets are known as [[ice giants]] because during their formation, these elements are thought to have been incorporated into them as ice; however, they probably contain very little ice.<ref name=icegiantatmospheres>{{citation | url=https://www.lpi.usra.edu/decadal/opag/IceGiantAtmospheres_v7.pdf | last=Hofstadter | first=Mark | title=The Atmospheres of the Ice Giants, Uranus and Neptune | year=2011 | publisher=[[National Research Council (United States)|US National Research Council]] | access-date=January 18, 2015 | work=White Paper for the [[Planetary Science Decadal Survey]] | pages=1–2 | archive-date=July 17, 2023 | archive-url=https://web.archive.org/web/20230717232018/https://www.lpi.usra.edu/decadal/opag/IceGiantAtmospheres_v7.pdf | url-status=live }}</ref>

=== Size and mass ===
{{Main|Jupiter mass}}
[[File:Jupiter size.png|alt=Refer to caption|thumb|Size of Jupiter compared to Earth and Earth's Moon]]

Jupiter is about eleven times wider than the Earth ({{val|11.209|ul=R_Earth}}); while its mass is 318 times that of Earth<ref name="fact"/> which is 2.5 times the mass of all the other planets in the Solar System combined. It is so massive that its [[barycentre]] with the Sun lies above the [[Photosphere|Sun's surface]] at 1.068&nbsp;[[solar radius|solar radii]] from the Sun's centre.<ref>{{cite book |last=MacDougal |first=Douglas W. |title=Newton's Gravity |url=https://archive.org/details/newtonsgravityin00macd |url-access=limited |year=2012 |publisher=Springer New York |isbn=978-1-4614-5443-4 |pages=[https://archive.org/details/newtonsgravityin00macd/page/n208 193]–211 |language=en |chapter=A Binary System Close to Home: How the Moon and Earth Orbit Each Other |quote=the barycentre is 743,000&nbsp;km from the centre of the Sun. The Sun's radius is 696,000&nbsp;km, so it is 47,000&nbsp;km above the surface.|doi=10.1007/978-1-4614-5444-1_10 |series=Undergraduate Lecture Notes in Physics }}</ref><ref name="burgess">{{cite book |first=Eric |last=Burgess |date=1982 |title=By Jupiter: Odysseys to a Giant |publisher=Columbia University Press |location=New York |isbn=978-0-231-05176-7}}</ref> Jupiter's radius is about one tenth the radius of the Sun ({{val|0.10276|ul=R_Solar}}),<ref name="shu82">{{cite book |first=Frank H. |last=Shu |date=1982 |title=The physical universe: an introduction to astronomy |page=[https://archive.org/details/physicaluniverse00shuf/page/426 426] |series=Series of books in astronomy |edition=12th |publisher=University Science Books |isbn=978-0-935702-05-7 |url=https://archive.org/details/physicaluniverse00shuf/page/426 }}</ref> and its mass is one thousandth the [[Solar mass|mass of the Sun]], of which the densities of the two bodies are similar.<ref name="davis_turekian05">{{cite book | last1=Davis | first1=Andrew M. | last2=Turekian | first2=Karl K. | title=Meteorites, comets, and planets | volume=1 | series=Treatise on geochemistry | publisher=Elsevier | date=2005 | isbn=978-0-08-044720-9 | page=624}}</ref> A "[[Jupiter mass]]" ({{Jupiter mass}} or {{Jupiter mass|Jup=y}}) is used as a unit to describe masses of other objects, particularly [[extrasolar planet]]s and [[brown dwarf]]s. For example, the extrasolar planet [[HD 209458 b]] has a mass of {{Jupiter mass|0.69}}, while the brown dwarf [[Gliese 229 b]] has a mass of {{Jupiter mass|60.4}}.<ref>{{cite encyclopedia |url=https://exoplanet.eu/home/ |title=The Extrasolar Planets Encyclopedia: Interactive Catalogue |first=Jean |last=Schneider |year=2009 |access-date=August 9, 2014 |archive-date=October 28, 2023 |archive-url=https://web.archive.org/web/20231028155019/https://exoplanet.eu/home/ |encyclopedia=[[Extrasolar Planets Encyclopaedia]] |url-status=live }}</ref><ref name="Feng2022">{{cite journal |last1=Feng |first1=Fabo |last2=Butler |first2=R. Paul |display-authors=etal |date=August 2022 |title=3D Selection of 167 Substellar Companions to Nearby Stars |journal=[[The Astrophysical Journal Supplement Series]] |volume=262 |issue=21 |page=21 |doi=10.3847/1538-4365/ac7e57 |arxiv=2208.12720 |bibcode=2022ApJS..262...21F|s2cid=251864022 |doi-access=free }}</ref>

Theoretical models indicate that if Jupiter had over 40% more mass, the interior would be so compressed that its volume would ''decrease'' despite the increasing amount of matter. For smaller changes in its mass, the [[radius]] would not change appreciably.<ref name="Seager2007">{{cite journal | last1=Seager | first1=S. | last2=Kuchner | first2=M. | last3=Hier-Majumder | first3=C. A. | last4=Militzer | first4=B. | title=Mass-Radius Relationships for Solid Exoplanets | journal=The Astrophysical Journal | volume=669 | issue=2 | pages=1279–1297 | year=2007 | doi=10.1086/521346 | arxiv=0707.2895 | bibcode=2007ApJ...669.1279S | s2cid=8369390 }}</ref> As a result, Jupiter is thought to have about as large a diameter as a planet of its composition and evolutionary history can achieve.<ref name="HTUW">{{cite AV media | title=How the Universe Works 3 | volume=Jupiter: Destroyer or Savior? |year=2014 | publisher=Discovery Channel}}</ref> The process of further shrinkage with increasing mass would continue until appreciable [[stellar ignition]] was achieved.<ref name="tristan286">{{cite journal
 | last=Guillot | first=Tristan
 | title=Interiors of Giant Planets Inside and Outside the Solar System
 | journal=Science
 | year=1999 | volume=286 | issue=5437 | pages=72–77
 | doi=10.1126/science.286.5437.72 | pmid=10506563
 | bibcode=1999Sci...286...72G | access-date=April 24, 2022
| url=http://web.gps.caltech.edu/~mbrown/classes/ge131/notes/guillot.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://web.gps.caltech.edu/~mbrown/classes/ge131/notes/guillot.pdf |archive-date=October 9, 2022 |url-status=live
}}</ref> Although Jupiter would need to be about 75 times more massive to [[hydrogen fusion|fuse hydrogen]] and become a [[star]],<ref>{{cite journal | title=The theory of brown dwarfs and extrasolar giant planets | last1=Burrows | first1=Adam | last2=Hubbard | first2=W. B. | last3=Lunine | first3=J. I. | last4=Liebert | first4=James | journal=Reviews of Modern Physics | volume=73 | issue=3 | pages=719–765 | date=July 2001 | doi=10.1103/RevModPhys.73.719 | arxiv=astro-ph/0103383 | bibcode=2001RvMP...73..719B | s2cid=204927572 | quote=Hence the HBMM at solar metallicity and Y<sub>α</sub> = 50.25 is 0.07 – 0.074 {{solar mass}}, ... while the HBMM at zero metallicity is 0.092 {{solar mass}} }}</ref> its diameter is sufficient as the smallest [[red dwarf]] may be slightly larger in radius than Saturn.<ref>{{cite journal
 | title=The EBLM project. III. A Saturn-size low-mass star at the hydrogen-burning limit
 | last1=von Boetticher | first1=Alexander | last2=Triaud | first2=Amaury H. M. J.
 | last3=Queloz | first3=Didier | last4=Gill | first4=Sam
 | last5=Lendl | first5=Monika | last6=Delrez | first6=Laetitia
 | last7=Anderson | first7=David R. | last8=Collier Cameron | first8=Andrew
 | last9=Faedi | first9=Francesca | last10=Gillon | first10=Michaël
 | last11=Gómez Maqueo Chew | first11=Yilen | last12=Hebb | first12=Leslie
 | last13=Hellier | first13=Coel | last14=Jehin | first14=Emmanuël
 | last15=Maxted | first15=Pierre F. L. | last16=Martin | first16=David V.
 | last17=Pepe | first17=Francesco | last18=Pollacco | first18=Don
 | last19=Ségransan | first19=Damien | last20=Smalley | first20=Barry
 | last21=Udry | first21=Stéphane | last22=West | first22=Richard
 | journal=Astronomy & Astrophysics | volume=604 | id=L6 | pages=6
 | date=August 2017 | doi=10.1051/0004-6361/201731107
 | arxiv=1706.08781 | bibcode=2017A&A...604L...6V | s2cid=54610182 }}</ref>

Jupiter radiates more heat than it receives through solar radiation, due to the [[Kelvin–Helmholtz mechanism]] within its contracting interior.<ref name="elkins-tanton">{{cite book
 | first=Linda T. | last=Elkins-Tanton |date=2011
 | title=Jupiter and Saturn | publisher=Chelsea House
 | location=New York | isbn=978-0-8160-7698-7 | edition=revised
}}</ref>{{rp|30}}<ref>{{cite book
 | title=Giant Planets of Our Solar System: Atmospheres, Composition, and Structure
 | first=Patrick
 | last=Irwin
 | date=2003
 | page=62
 | isbn=978-3-540-00681-7
 | publisher=Springer Science & Business Media
 | url=https://books.google.com/books?id=p8wCsJweUb0C&pg=PA62
 | access-date=April 23, 2022
| archive-date=June 19, 2024
| archive-url=https://web.archive.org/web/20240619015914/https://books.google.com/books?id=p8wCsJweUb0C&pg=PA62#v=onepage&q&f=false
 | url-status=live
 }}</ref> This process causes Jupiter to shrink by about {{cvt|1|mm}} per year.<ref>{{cite book | title = Giant Planets of Our Solar System: Atmospheres, Composition, and Structure | first = Patrick G. J. | last = Irwin | publisher = Springer | orig-year = 2003 | url = https://books.google.com/books?id=p8wCsJweUb0C&q=%22kelvin+helmholtz+mechanism%22&pg=PA63 | edition = Second | year = 2009 | page = 4 | quote = the radius of Jupiter is estimated to be currently shrinking by approximately 1&nbsp;mm/yr | isbn = 978-3-642-09888-8 | access-date = March 6, 2021 | archive-date = June 19, 2024 | archive-url = https://web.archive.org/web/20240619015915/https://books.google.com/books?id=p8wCsJweUb0C&q=%22kelvin+helmholtz+mechanism%22&pg=PA63#v=snippet&q=%22kelvin%20helmholtz%20mechanism%22&f=false | url-status = live }}.</ref><ref name="guillot04">{{cite book | editor1-last=Bagenal | editor1-first=Fran | editor2-last=Dowling | editor2-first=Timothy E. | editor3-last=McKinnon | editor3-first=William B. | last1=Guillot | first1=Tristan | last2=Stevenson | first2=David J. | last3=Hubbard | first3=William B. | last4=Saumon | first4=Didier | date=2004 | title=Jupiter: The Planet, Satellites and Magnetosphere | chapter=Chapter 3: The Interior of Jupiter | publisher=[[Cambridge University Press]] | isbn=978-0-521-81808-7 }}</ref> At the time of its formation, Jupiter was hotter and was about twice its current diameter.<ref>{{cite journal |last=Bodenheimer |first=P. |title=Calculations of the early evolution of Jupiter |series=23 |journal=Icarus |year=1974 |issue=3 |volume=23 |pages=319–325 |bibcode=1974Icar...23..319B |doi=10.1016/0019-1035(74)90050-5}}</ref>

=== Internal structure ===
[[File:Jupiter diagram.svg|thumb|upright=2|alt=Refer to caption|Diagram of Jupiter with its interior, surface features, rings, and inner moons]]
Before the early 21st century, most scientists proposed one of two scenarios for the formation of Jupiter. If the planet accreted first as a solid body, it would consist of a dense [[planetary core|core]], a surrounding layer of fluid [[metallic hydrogen]] (with some helium) extending outward to about 80% of the radius of the planet,<ref>{{cite journal | last=Smoluchowski | first=R. | year=1971 | title=Metallic interiors and magnetic fields of Jupiter and Saturn | journal=The Astrophysical Journal | volume=166 | page=435 | doi=10.1086/150971 | bibcode=1971ApJ...166..435S | doi-access=free }}</ref> and an outer atmosphere consisting primarily of [[molecular hydrogen]].<ref name="guillot04"/> Alternatively, if the planet collapsed directly from the gaseous [[protoplanetary disk]], it was expected to completely lack a core, consisting instead of a denser and denser fluid (predominantly molecular and metallic hydrogen) all the way to the centre. Data from the [[Juno (spacecraft)|''Juno'' mission]] showed that Jupiter has a diffuse core that mixes into its mantle, extending for 30–50% of the planet's radius, and comprising heavy elements with a combined mass 7–25 times the Earth.<ref>{{cite journal |last1=Wahl |first1=S. M. |last2=Hubbard |first2=William B. |last3=Militzer |first3=B. |last4=Guillot |first4=Tristan |last5=Miguel |first5=Y. |last6=Movshovitz |first6=N. |last7=Kaspi |first7=Y. |last8=Helled |first8=R. |last9=Reese |first9=D. |last10=Galanti |first10=E. |last11=Levin |first11=S. |last12=Connerney |first12=J. E. |last13=Bolton |first13=S. J. |title=Comparing Jupiter interior structure models to Juno gravity measurements and the role of a dilute core |journal=Geophysical Research Letters |volume=44 |issue=10 |pages=4649–4659 |year=2017 |doi=10.1002/2017GL073160 |doi-access=free |arxiv=1707.01997 |bibcode=2017GeoRL..44.4649W }}</ref><ref name=dilute>{{cite journal|title=The Formation of Jupiter's Diluted Core by a Giant Impact|journal=Nature|date=August 15, 2019|author=Shang-Fei Liu|display-authors=et al.|doi=10.1038/s41586-019-1470-2|volume=572|issue=7769 |pages=355–357|pmid=31413376 |arxiv=2007.08338|bibcode=2019Natur.572..355L |s2cid=199576704 }}</ref><ref name="NYT-20160705">{{cite news |last=Chang |first=Kenneth |date=July 5, 2016 |title=NASA's Juno Spacecraft Enters Jupiter's Orbit |work=[[The New York Times]] |url=https://www.nytimes.com/2016/07/05/science/juno-enters-jupiters-orbit-capping-5-year-voyage.html |access-date=July 5, 2016 |archive-date=May 2, 2019 |archive-url=https://web.archive.org/web/20190502211501/https://www.nytimes.com/2016/07/05/science/juno-enters-jupiters-orbit-capping-5-year-voyage.html |url-status=live }}</ref> This mixing process could have arisen during formation, while the planet accreted solids and gases from the surrounding nebula.<ref name="stevenson2022">{{cite journal| last1=Stevenson| first1=D. J.| last2=Bodenheimer| first2=P.| last3=Lissauer| first3=J. J.| last4=D'Angelo| first4=G.| title= Mixing of Condensable Constituents with H-He during the Formation and Evolution of Jupiter|year=2022| journal=The Planetary Science Journal| volume=3| pages=id.74| issue=4| doi=10.3847/PSJ/ac5c44| arxiv=2202.09476| bibcode=2022PSJ.....3...74S| s2cid=247011195| doi-access=free}}</ref> Alternatively, it could have been caused by an impact from a planet of about ten Earth masses a few million years after Jupiter's formation, which would have disrupted an originally compact Jovian core.<ref name=dilute/><ref name="nature2019_2">{{cite journal| last=Guillot| first=T.|year=2019| journal=Nature| pages=315–317| issue=7769| title=Signs that Jupiter was mixed by a giant impact| volume=572| doi=10.1038/d41586-019-02401-1| pmid=31413374| bibcode=2019Natur.572..315G| doi-access=free}}</ref>

Outside the layer of metallic hydrogen lies a transparent interior atmosphere of hydrogen. At this depth, the pressure and temperature are above molecular hydrogen's [[critical pressure]] of 1.3 [[Pascal (unit)|MPa]] and [[critical temperature]] of {{cvt|33|K|C F|lk=on}}.<ref>{{cite journal | title=Dynamic transition of supercritical hydrogen: Defining the boundary between interior and atmosphere in gas giants | last1=Trachenko | first1=K. | last2=Brazhkin | first2=V. V. | last3=Bolmatov | first3=D. | journal=Physical Review E | volume=89 | issue=3 | id=032126 | date=March 2014 | page=032126 | doi=10.1103/PhysRevE.89.032126 | pmid=24730809 | arxiv=1309.6500 | bibcode=2014PhRvE..89c2126T | s2cid=42559818 }}</ref> In this state, there are no distinct liquid and gas phases—hydrogen is said to be in a [[supercritical fluid]] state. The hydrogen and helium gas extending downward from the cloud layer gradually transitions to a liquid in deeper layers, possibly resembling something akin to an ocean of liquid hydrogen and other supercritical fluids.<ref name="elkins-tanton"/>{{rp|22}}<ref>{{cite web | first=Dauna | last=Coulter | title=A Freaky Fluid inside Jupiter? | url=https://science.nasa.gov/science-news/science-at-nasa/2011/09aug_juno3 | website=[[NASA]] | access-date=December 8, 2021 | archive-date=December 9, 2021 | archive-url=https://web.archive.org/web/20211209022840/https://science.nasa.gov/science-news/science-at-nasa/2011/09aug_juno3 | url-status=dead }}</ref><ref>{{cite web|title= NASA System Exploration Jupiter|url= https://solarsystem.nasa.gov/planets/jupiter/in-depth.amp|website= [[NASA]]|access-date= December 8, 2021|archive-date= November 4, 2021|archive-url= https://web.archive.org/web/20211104172628/https://solarsystem.nasa.gov/planets/jupiter/in-depth.amp|url-status= live}}</ref> Physically, the gas gradually becomes hotter and denser as depth increases.<ref>{{cite journal |last=Guillot |first=T. |title=A comparison of the interiors of Jupiter and Saturn |journal=Planetary and Space Science |year=1999 |volume=47 |issue=10–11 |pages=1183–1200 |bibcode=1999P&SS...47.1183G |arxiv=astro-ph/9907402 |doi=10.1016/S0032-0633(99)00043-4 |s2cid=19024073 |url=https://cds.cern.ch/record/394768 |access-date=June 21, 2023 |archive-date=May 19, 2021 |archive-url=https://web.archive.org/web/20210519002044/http://cds.cern.ch/record/394768 |url-status=live }}</ref><ref name="lang03">{{cite web |last=Lang |first=Kenneth R. |year=2003 |url=http://ase.tufts.edu/cosmos/view_chapter.asp?id=9&page=3 |title=Jupiter: a giant primitive planet |publisher=NASA |access-date=January 10, 2007 |archive-date=May 14, 2011 |archive-url=https://web.archive.org/web/20110514093512/http://ase.tufts.edu/cosmos/view_chapter.asp?id=9&page=3 |url-status=dead }}</ref>

Rain-like droplets of helium and neon precipitate downward through the lower atmosphere, depleting the abundance of these elements in the upper atmosphere.<ref name="galileo_ms"/><ref>{{cite journal |last=Lodders |first=Katharina|author-link=Katharina Lodders |title=Jupiter Formed with More Tar than Ice |journal=The Astrophysical Journal |year=2004 |volume=611 |issue=1 |pages=587–597 |doi=10.1086/421970 |bibcode=2004ApJ...611..587L|s2cid=59361587 |url=http://pdfs.semanticscholar.org/afa4/68519084fe3a3076b614442803056943e202.pdf |archive-url=https://web.archive.org/web/20200412141533/http://pdfs.semanticscholar.org/afa4/68519084fe3a3076b614442803056943e202.pdf |url-status=dead |archive-date=April 12, 2020 }}</ref> Calculations suggest that helium drops separate from metallic hydrogen at a radius of {{Convert|60000|km|mi|abbr=unit}} ({{Convert|11000|km|mi|abbr=unit|disp=sqbr}} below the cloud tops) and merge again at {{Convert|50000|km|mi|abbr=unit}} ({{Convert|22000|km|mi|abbr=unit|disp=sqbr}} beneath the clouds).<ref>{{cite journal
 | title=Evidence of hydrogen−helium immiscibility at Jupiter-interior conditions
 | last1=Brygoo | first1=S. | last2=Loubeyre | first2=P.
 | last3=Millot | first3=M. | last4=Rygg | first4=J. R.
 | last5=Celliers | first5=P. M. | last6=Eggert | first6=J. H.
 | last7=Jeanloz | first7=R. | last8=Collins | first8=G. W.
 | journal=Nature | volume=593 | issue=7860 | pages=517–521
 | year=2021 | doi=10.1038/s41586-021-03516-0 | pmid=34040210 | bibcode=2021Natur.593..517B
| osti=1820549 | s2cid=235217898 }}</ref> Rainfalls of [[extraterrestrial diamonds|diamonds]] have been suggested to occur, as well as on Saturn<ref name="SC-20131009">{{cite news |last=Kramer |first=Miriam |title=Diamond Rain May Fill Skies of Jupiter and Saturn |url=https://www.space.com/23135-diamond-rain-jupiter-saturn.html |date=October 9, 2013 |work=[[Space.com]] |access-date=August 27, 2017 |archive-date=August 27, 2017 |archive-url=https://web.archive.org/web/20170827171415/https://www.space.com/23135-diamond-rain-jupiter-saturn.html |url-status=live }}</ref> and the ice giants Uranus and Neptune.<ref name="WP-20170825">{{cite news |last=Kaplan |first=Sarah |title=It rains solid diamonds on Uranus and Neptune |url=https://www.washingtonpost.com/news/speaking-of-science/wp/2017/08/25/it-rains-solid-diamonds-on-uranus-and-neptune/ |date=August 25, 2017 |newspaper=[[The Washington Post]] |access-date=August 27, 2017 |archive-date=August 27, 2017 |archive-url=https://web.archive.org/web/20170827011901/https://www.washingtonpost.com/news/speaking-of-science/wp/2017/08/25/it-rains-solid-diamonds-on-uranus-and-neptune/ |url-status=live }}</ref>

The temperature and pressure inside Jupiter increase steadily inward as the heat of planetary formation can only escape by convection.<ref name="Juno"/> At a surface depth where the atmospheric pressure level is {{cvt|1|bar|MPa|lk=on}}, the temperature is around {{cvt|165|K|C F}}. The region where supercritical hydrogen changes gradually from a molecular fluid to a metallic fluid spans pressure ranges of {{cvt|500000|-|4000000|bar|GPa|disp=out}} with temperatures of {{cvt|5000|-|8400|K|C F}}, respectively. The temperature of Jupiter's diluted core is estimated to be {{cvt|20000|K|C F}} with a pressure of around {{convert|40|e6bar|GPa|disp=out|abbr=unit}}.<ref name=Guillot_et_al_2004>{{cite book | chapter=The interior of Jupiter | bibcode=2004jpsm.book...35G | last1=Guillot | first1=Tristan | last2=Stevenson | first2=David J. | last3=Hubbard | first3=William B. | last4=Saumon | first4=Didier | title=Jupiter. The planet, satellites and magnetosphere | editor1-first=Fran | editor1-last=Bagenal | editor2-first=Timothy E. | editor2-last=Dowling | editor3-first=William B. | editor3-last=McKinnon | series=Cambridge planetary science | volume=1 | publication-place=Cambridge, UK | publisher=Cambridge University Press | isbn=0-521-81808-7 | date=2004 | page=45 | chapter-url=https://books.google.com/books?id=aMERHqj9ivcC&pg=PA45 | access-date=March 19, 2023 | archive-date=March 26, 2023 | archive-url=https://web.archive.org/web/20230326164803/https://books.google.com/books?id=aMERHqj9ivcC&pg=PA45 | url-status=live }}</ref>

=== Atmosphere ===
{{Main|Atmosphere of Jupiter}}
The atmosphere of Jupiter is primarily composed of molecular hydrogen and helium, with a smaller amount of other compounds such as water, methane, hydrogen sulfide, and ammonia.<ref name="Atreya2003"/> Jupiter's atmosphere extends to a depth of approximately {{convert|3000|km|-3}} below the cloud layers.<ref name="Guillot_et_al_2004"/>

==== Cloud layers ====
[[File:790106-0203 Voyager 58M to 31M reduced.gif|thumb|alt=Black and white animation of Jupiter's clouds by ''Voyager 1'' as the spacecraft approaches the planet|Timelapse of Jupiter's cloud system moving over the course of one month (photographed during ''[[Voyager 1]]'' flyby in 1979)]]
Jupiter is perpetually covered with clouds of ammonia crystals, which may contain [[ammonium hydrosulfide]] as well.<ref>{{cite journal | title=Coloring Jupiter's clouds: Radiolysis of ammonium hydrosulfide (NH4SH) | last1=Loeffler | first1=Mark J. | last2=Hudson | first2=Reggie L. | journal=Icarus | volume=302 | pages=418–425 | date=March 2018 | doi=10.1016/j.icarus.2017.10.041 | bibcode=2018Icar..302..418L | url=https://science.gsfc.nasa.gov/691/cosmicice/reprints/NH4SH_Icarus_Loeffler_Hudson_2018.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://science.gsfc.nasa.gov/691/cosmicice/reprints/NH4SH_Icarus_Loeffler_Hudson_2018.pdf |archive-date=October 9, 2022 |url-status=live | access-date=April 25, 2022 }}</ref> The clouds are located in the [[tropopause]] layer of the atmosphere, forming bands at different latitudes, known as tropical regions. These are subdivided into lighter-hued ''zones'' and darker ''belts''. The interactions of these conflicting [[Atmospheric circulation|circulation]] patterns cause storms and [[turbulence]]. Wind speeds of {{convert|100|m/s|km/h mph}} are common in [[Jet stream#Other planets|zonal jet streams]].<ref>{{cite book
 | chapter=Dynamics of Jupiter's Atmosphere
 | last1=Ingersoll | first1=Andrew P. | author-link1=Andrew Ingersoll
 | last2=Dowling | first2=Timothy E. | last3=Gierasch | first3=Peter J.
 | last4=Orton | first4=Glenn S. | last5=Read | first5=Peter L.
 | last6=Sánchez-Lavega | first6=Agustin | last7=Showman | first7=Adam P.
 | last8=Simon-Miller | first8=Amy A. | last9=Vasavada | first9=Ashwin R.
 | title=Jupiter. The Planet, Satellites and Magnetosphere
 | editor1-first=Fran | editor1-last=Bagenal
 | editor2-first=Timothy E. | editor2-last=Dowling
 | editor3-first=William B. | editor3-last=McKinnon
 | series=Cambridge planetary science | volume=1
 | publication-place=Cambridge, UK
 | publisher=Cambridge University Press
 | isbn=0-521-81808-7 | date=2004 | pages=105–128
 | bibcode=2004jpsm.book..105I | url=https://authors.library.caltech.edu/36015/1/Ingersoll_p105.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://authors.library.caltech.edu/36015/1/Ingersoll_p105.pdf |archive-date=October 9, 2022 |url-status=live
 | access-date=March 8, 2022 }}</ref> The zones have been observed to vary in width, colour and intensity from year to year, but they have remained stable enough for scientists to name them.<ref name="burgess"/>{{rp|6}}

The cloud layer is about {{cvt|50|km|0}} deep and consists of at least two decks of ammonia clouds: a thin, clearer region on top and a thicker, lower deck. There may be a thin layer of [[water (properties)|water]] clouds underlying the ammonia clouds, as suggested by flashes of [[lightning]] detected in the atmosphere of Jupiter.<ref>{{cite journal | title=Lightning Generation in Moist Convective Clouds and Constraints on the Water Abundance in Jupiter | last1=Aglyamov | first1=Yury S. | last2=Lunine | first2=Jonathan | last3=Becker | first3=Heidi N. |author3-link=Heidi N. Becker| last4=Guillot | first4=Tristan | last5=Gibbard | first5=Seran G. | last6=Atreya | first6=Sushil | last7=Bolton | first7=Scott J. | last8=Levin | first8=Steven | last9=Brown | first9=Shannon T. | last10=Wong | first10=Michael H. | journal=Journal of Geophysical Research: Planets | volume=126 | issue=2 | id=e06504 | date=February 2021 | doi=10.1029/2020JE006504 | arxiv=2101.12361 | bibcode=2021JGRE..12606504A | s2cid=231728590 }}</ref> These electrical discharges can be up to a thousand times as powerful as lightning on Earth.<ref>{{cite web |editor1-last=Watanabe |editor1-first=Susan |date=February 25, 2006 |url=http://www.nasa.gov/vision/universe/solarsystem/galileo_end.html |title=Surprising Jupiter: Busy Galileo spacecraft showed jovian system is full of surprises |publisher=NASA |access-date=February 20, 2007 |archive-date=October 8, 2011 |archive-url=https://web.archive.org/web/20111008010724/http://www.nasa.gov/vision/universe/solarsystem/galileo_end.html |url-status=dead }}</ref> The water clouds are assumed to generate thunderstorms in the same way as terrestrial thunderstorms, driven by the heat rising from the interior.<ref>{{cite journal |last=Kerr |first=Richard A. |author-link=Richard Kerr (science journalist) |title=Deep, Moist Heat Drives Jovian Weather |journal=Science |year=2000 |volume=287 |issue=5455 |pages=946–947 |doi=10.1126/science.287.5455.946b |s2cid=129284864 |url=https://www.proquest.com/openview/d4cfc37399ab62ac9e0668fd231cb072/1?pq-origsite=gscholar&cbl=1256 |access-date=April 26, 2022 |archive-date=February 3, 2023 |archive-url=https://web.archive.org/web/20230203043417/https://www.proquest.com/openview/d4cfc37399ab62ac9e0668fd231cb072/1?pq-origsite=gscholar&cbl=1256 |url-status=live }}</ref> The Juno mission revealed the presence of "shallow lightning" which originates from ammonia-water clouds relatively high in the atmosphere.<ref>{{cite journal | title=Small lightning flashes from shallow electrical storms on Jupiter | last1=Becker | first1=Heidi N. | author1-link=Heidi N. Becker | last2=Alexander | first2=James W. | last3=Atreya | first3=Sushil K. | last4=Bolton | first4=Scott J. | last5=Brennan | first5=Martin J. | last6=Brown | first6=Shannon T. | last7=Guillaume | first7=Alexandre | last8=Guillot | first8=Tristan | last9=Ingersoll | first9=Andrew P. | last10=Levin | first10=Steven M. | last11=Lunine | first11=Jonathan I. | last12=Aglyamov | first12=Yury S. | last13=Steffes | first13=Paul G. | journal=Nature | volume=584 | issue=7819 | pages=55–58 | year=2020 | doi=10.1038/s41586-020-2532-1 | pmid=32760043 | bibcode=2020Natur.584...55B | s2cid=220980694 | issn=0028-0836 | url=https://hal.archives-ouvertes.fr/hal-03058480 | access-date=March 6, 2021 | archive-date=September 29, 2021 | archive-url=https://web.archive.org/web/20210929074856/https://hal.archives-ouvertes.fr/hal-03058480 | url-status=live }}</ref> These discharges carry "mushballs" of water-ammonia slushes covered in ice, which fall deep into the atmosphere.<ref>{{cite journal
 | title=Storms and the Depletion of Ammonia in Jupiter: I. Microphysics of "Mushballs"
 | last1=Guillot | first1=Tristan | last2=Stevenson | first2=David J. | last3=Atreya | first3=Sushil K. | last4=Bolton | first4=Scott J. | last5=Becker | first5=Heidi N.|author5-link=Heidi N. Becker
 | journal=Journal of Geophysical Research: Planets
 | year=2020 | volume=125 | issue=8 | page=e2020JE006403 | doi=10.1029/2020JE006404
 | arxiv=2012.14316 | bibcode=2020JGRE..12506403G | s2cid=226194362 }}</ref> [[Upper-atmospheric lightning]] has been observed in Jupiter's upper atmosphere, bright flashes of light that last around 1.4{{Nbsp}}milliseconds. These are known as "elves" or "sprites" and appear blue or pink due to the hydrogen.<ref>{{cite journal
 | title=Possible Transient Luminous Events Observed in Jupiter's Upper Atmosphere
 | last1=Giles | first1=Rohini S. | last2=Greathouse | first2=Thomas K. | last3=Bonfond | first3=Bertrand | last4=Gladstone | first4=G. Randall | last5=Kammer | first5=Joshua A. | last6=Hue | first6=Vincent | last7=Grodent | first7=Denis C. | last8=Gérard | first8=Jean-Claude | last9=Versteeg | first9=Maarten H. | last10=Wong | first10=Michael H. | last11=Bolton | first11=Scott J. | last12=Connerney | first12=John E. P. | last13=Levin | first13=Steven M.
 | journal=Journal of Geophysical Research: Planets
 | year=2020 | volume=125 | issue=11 | pages=e06659 | id=e06659
 | doi=10.1029/2020JE006659 | arxiv=2010.13740
 | bibcode=2020JGRE..12506659G | s2cid=225075904 }}</ref><ref>{{cite web | title=Juno Data Indicates 'Sprites' or 'Elves' Frolic in Jupiter's Atmosphere | date=October 27, 2020 | editor-first=Tony | editor-last=Greicius | website=NASA | url=https://www.nasa.gov/feature/jpl/juno-data-indicates-sprites-or-elves-frolic-in-jupiters-atmosphere | access-date=December 30, 2020 | archive-date=January 27, 2021 | archive-url=https://web.archive.org/web/20210127211238/https://www.nasa.gov/feature/jpl/juno-data-indicates-sprites-or-elves-frolic-in-jupiters-atmosphere/ | url-status=live }}</ref>

The orange and brown colours in the clouds of Jupiter are caused by upwelling compounds that change colour when they are exposed to ultraviolet light from the Sun. The exact makeup remains uncertain, but the substances are thought to be made up of phosphorus, sulfur or possibly hydrocarbons.<ref name="elkins-tanton"/>{{rp|39}}<ref>{{cite conference | last1=Strycker | first1=P. D. | last2=Chanover | first2=N. | last3=Sussman | first3=M. | last4=Simon-Miller | first4=A. |title=A Spectroscopic Search for Jupiter's Chromophores |work=DPS meeting No. 38, #11.15 |publisher=American Astronomical Society |year=2006 |bibcode=2006DPS....38.1115S}}</ref> These colourful compounds, known as [[chromophore]]s, mix with the warmer clouds of the lower deck. The light-coloured zones are formed when rising [[convection cell]]s form crystallising ammonia that hides the chromophores from view.<ref name="worldbook">{{cite web | last1=Gierasch | first1=Peter J. | last2=Nicholson | first2=Philip D. |author-link2=Phil Nicholson|year=2004 | url=http://www.nasa.gov/worldbook/jupiter_worldbook.html |archive-url=https://web.archive.org/web/20050105155019/http://www.nasa.gov/worldbook/jupiter_worldbook.html | url-status=dead | archive-date=January 5, 2005 | title=Jupiter | publisher=World Book @ NASA | access-date=August 10, 2006 }}</ref>

Jupiter has a low [[axial tilt]], thus ensuring that the poles always receive less [[solar radiation]] than the planet's equatorial region. [[Convection]] within the interior of the planet transports energy to the poles, balancing out temperatures at the cloud layer.<ref name="burgess"/>{{rp|54}}

==== Great Red Spot and other vortices ====
[[File:PIA21775.jpg|thumb|alt=A very distorted image of a large, red anticyclonic storm|Close-up of the Great Red Spot imaged by the [[Juno spacecraft|''Juno'' spacecraft]] in true colour. Due to the way ''Juno'' takes photographs, the stitched image has extreme [[barrel distortion]].]]
A well-known feature of Jupiter is the [[Great Red Spot]],<ref name="NYT-20171213">{{cite news |last=Chang |first=Kenneth |title=The Great Red Spot Descends Deep into Jupiter |url=https://www.nytimes.com/2017/12/13/science/jupiter-great-red-spot-juno.html |date=December 13, 2017 |work=[[The New York Times]] |access-date=December 15, 2017 |archive-date=December 15, 2017 |archive-url=https://web.archive.org/web/20171215042159/https://www.nytimes.com/2017/12/13/science/jupiter-great-red-spot-juno.html |url-status=live }}</ref> a persistent [[anticyclonic storm]] located 22° south of the equator. It was first observed in 1831,<ref>{{cite journal |last=Denning |first=William F. |author-link=William Frederick Denning|title=Jupiter, early history of the great red spot on |journal=[[Monthly Notices of the Royal Astronomical Society]] |year=1899 |volume=59 |issue=10 |pages=574–584 |bibcode=1899MNRAS..59..574D |doi=10.1093/mnras/59.10.574|doi-access=free }}</ref> and possibly as early as 1665.<ref name="kyrala26">{{cite journal |last=Kyrala |first=A. |title=An explanation of the persistence of the Great Red Spot of Jupiter |journal=Moon and the Planets |year=1982 |volume=26 |issue=1 |pages=105–107 |bibcode=1982M&P....26..105K |doi=10.1007/BF00941374|s2cid=121637752 }}</ref><ref>{{cite web | url=http://www.gutenberg.org/files/28758/28758-h/28758-h.htm | title=Philosophical Transactions of the Royal Society | editor-first=Henry | editor-last=Oldenburg | volume=1 | date=1665–1666 | publisher=Project Gutenberg | access-date=December 22, 2011 | archive-date=March 4, 2016 | archive-url=https://web.archive.org/web/20160304001941/http://www.gutenberg.org/files/28758/28758-h/28758-h.htm | url-status=live }}</ref> Images by the [[Hubble Space Telescope]] have shown two more "red spots" adjacent to the Great Red Spot.<ref>{{cite web|title=New Red Spot Appears on Jupiter|url=http://hubblesite.org/newscenter/archive/releases/2008/23/image/a/|last1=Wong|first1=M.|last2=de Pater|first2=I.|website=HubbleSite|publisher=[[NASA]]|date=May 22, 2008|access-date=December 12, 2013|archive-date=December 16, 2013|archive-url=https://web.archive.org/web/20131216055125/http://hubblesite.org/newscenter/archive/releases/2008/23/image/a/|url-status=live}}</ref><ref>{{cite web|title=Three Red Spots Mix It Up on Jupiter|url=http://hubblesite.org/newscenter/archive/releases/2008/27/image/a/|last1=Simon-Miller|first1=A.|last2=Chanover|first2=N.|last3=Orton|first3=G.|website=HubbleSite|publisher=[[NASA]]|date=July 17, 2008|access-date=April 26, 2015|archive-date=May 1, 2015|archive-url=https://web.archive.org/web/20150501093610/http://hubblesite.org/newscenter/archive/releases/2008/27/image/a/|url-status=live}}</ref> The storm is visible through Earth-based [[telescope]]s with an [[aperture]] of 12&nbsp;cm or larger.<ref>{{cite book |first=Michael A. |last=Covington |date=2002 |title=Celestial Objects for Modern Telescopes |page=[https://archive.org/details/celestialobjects00covi/page/53 53] |publisher=Cambridge University Press |isbn=978-0-521-52419-3 |url=https://archive.org/details/celestialobjects00covi/page/53 }}</ref> The storm rotates counterclockwise, with a [[period (physics)|period]] of about six days.<ref>{{cite web | last1=Cardall | first1=C. Y. | last2=Daunt | first2=S. J. | url=http://csep10.phys.utk.edu/astr161/lect/jupiter/redspot.html | title=The Great Red Spot | publisher=University of Tennessee | access-date=February 2, 2007 | archive-date=March 31, 2010 | archive-url=https://web.archive.org/web/20100331125637/http://csep10.phys.utk.edu/astr161/lect/jupiter/redspot.html | url-status=live }}</ref> The maximum altitude of this storm is about {{convert|8|km|0}} above the surrounding cloud tops.<ref>{{cite book | title=Jupiter, the Giant of the Solar System | page=5 | publisher=NASA | date=1979 | url=https://books.google.com/books?id=KuBYXLt4K9MC&pg=PA5 | access-date=March 19, 2023 | archive-date=March 26, 2023 | archive-url=https://web.archive.org/web/20230326164803/https://books.google.com/books?id=KuBYXLt4K9MC&pg=PA5 | url-status=live }}</ref> The Spot's composition and the source of its red colour remain uncertain, although photodissociated [[ammonia]] reacting with [[acetylene]] is a likely explanation.<ref>{{cite journal | title=A possibly universal red chromophore for modeling colour variations on Jupiter | last1=Sromovsky | first1=L. A. | last2=Baines | first2=K. H. | last3=Fry | first3=P. M. | last4=Carlson | first4=R. W. | journal=Icarus | volume=291 | pages=232–244 | date=July 2017 | doi=10.1016/j.icarus.2016.12.014 | arxiv=1706.02779 | bibcode=2017Icar..291..232S | s2cid=119036239 }}</ref>

The Great Red Spot is larger than the Earth.<ref name="sp.news20151125">{{cite news |url=http://space.news/2015-11-25-is-jupiters-great-red-spot-nearing-its-twilight.html |title=Is Jupiter's Great Red Spot nearing its twilight? |work=Space.news |first=Greg |last=White |date=November 25, 2015 |access-date=April 13, 2017 |archive-date=April 14, 2017 |archive-url=https://web.archive.org/web/20170414082402/http://space.news/2015-11-25-is-jupiters-great-red-spot-nearing-its-twilight.html |url-status=live }}</ref> [[Mathematical model]]s suggest that the storm is stable and will be a permanent feature of the planet.<ref>{{cite journal |title=Laboratory simulation of Jupiter's Great Red Spot |first1=Jöel |last1=Sommeria |first2=Steven D. |last2=Meyers |first3=Harry L. |last3=Swinney |journal=Nature |volume=331 |issue=6158 |pages=689–693 |date=February 25, 1988 |doi=10.1038/331689a0 |bibcode=1988Natur.331..689S|s2cid=39201626 }}</ref> However, it has significantly decreased in size since its discovery. Initial observations in the late 1800s showed it to be approximately {{cvt|25500|mi|km|order=flip}} across. {{As of|2015}}, the storm was measured at approximately {{convert|10250|by|6800|mi|km|order=flip}},<ref name="Simon2015">{{cite conference |title=Dramatic Change in Jupiter's Great Red Spot |conference=46th Lunar and Planetary Science Conference. March 16–20, 2015. The Woodlands, Texas. |first1=Amy A. |last1=Simon | last2=Wong | first2=M. H. | last3=Rogers | first3=J. H. | last4=Orton | first4=G. S. | last5=de Pater | first5=I. | last6=Asay-Davis | first6=X. | last7=Carlson | first7=R. W. | last8=Marcus | first8=P. S. | date=March 2015 |bibcode=2015LPI....46.1010S}}</ref> and was decreasing in length by about {{cvt|580|mi|km|order=flip}} per year.<ref name="sp.news20151125"/> In October 2021, a ''Juno'' flyby mission measured the depth of the Great Red Spot, putting it at around {{convert|300|-|500|km}}.<ref>{{Cite web|last=Grush|first=Loren|date=October 28, 2021|title=NASA's ''Juno'' spacecraft finds just how deep Jupiter's Great Red Spot goes|url=https://www.theverge.com/2021/10/28/22749095/nasa-juno-jupiter-great-red-spot-depth|access-date=October 28, 2021|website=The Verge|language=en|archive-date=October 28, 2021|archive-url=https://web.archive.org/web/20211028212214/https://www.theverge.com/2021/10/28/22749095/nasa-juno-jupiter-great-red-spot-depth|url-status=live}}</ref>

''Juno'' missions found several cyclone groups at Jupiter's poles. The northern group contains nine cyclones, with a large one in the centre and eight others around it, while its southern counterpart also consists of a centre vortex but is surrounded by five large storms and a single smaller one for a total of seven storms.<ref name=Adriani_et_al_2018>{{cite journal| title=Clusters of cyclones encircling Jupiter's poles| last1=Adriani | first1=Alberto | last2=Mura | first2=A. | last3=Orton | first3=G. | last4=Hansen | first4=C. | last5=Altieri | first5=F. | last6=Moriconi | first6=M. L. | last7=Rogers | first7=J. | last8=Eichstädt | first8=G. | last9=Momary | first9=T. | last10=Ingersoll | first10=A. P. | last11=Filacchione | first11=G. | last12=Sindoni | first12=G. | last13=Tabataba-Vakili | first13=F. | last14=Dinelli | first14=B. M. | last15=Fabiano | first15=F. | last16=Bolton | first16=S. J. | last17=Connerney | first17=J. E. P. | last18=Atreya | first18=S. K. | last19=Lunine | first19=J. I. | last20=Tosi | first20=F. | last21=Migliorini | first21=A. | last22=Grassi | first22=D. | last23=Piccioni | first23=G. | last24=Noschese | first24=R. | last25=Cicchetti | first25=A. | last26=Plainaki | first26=C. | last27=Olivieri | first27=A. | last28=O'Neill | first28=M. E. | last29=Turrini | first29=D. | last30=Stefani | first30=S. | last31=Sordini | first31=R. | last32=Amoroso | first32=M. | display-authors=5 | journal=Nature |volume=555 |issue=7695 |pages=216–219|date=March 2018 |doi=10.1038/nature25491 |pmid=29516997 | bibcode=2018Natur.555..216A| s2cid=4438233 }}</ref><ref>{{cite web| title=NASA Just Watched a Mass of Cyclones on Jupiter Evolve Into a Mesmerising Hexagon| url=https://www.sciencealert.com/june-watched-a-pentagon-of-storms-on-jupiter-evolve-into-a-hexagon| last=Starr| first=Michelle| date=December 13, 2017| website=Science Alert| access-date=May 26, 2021| archive-date=May 26, 2021| archive-url=https://web.archive.org/web/20210526205728/https://www.sciencealert.com/june-watched-a-pentagon-of-storms-on-jupiter-evolve-into-a-hexagon| url-status=live}}</ref> 

In 2000, an atmospheric feature formed in the southern hemisphere that is similar in appearance to the Great Red Spot, but smaller. This was created when smaller, white oval-shaped storms merged to form a single feature—these three smaller white ovals were formed in 1939–1940. The merged feature was named [[Oval BA]]. It has since increased in intensity and changed from white to red, earning it the nickname "Little Red Spot".<ref>{{cite web |first=Bill |last=Steigerwald |date=October 14, 2006 |url=http://www.nasa.gov/centers/goddard/news/topstory/2006/little_red_spot.html |title=Jupiter's Little Red Spot Growing Stronger |publisher=NASA |access-date=February 2, 2007 |archive-date=April 5, 2012 |archive-url=https://web.archive.org/web/20120405155701/http://www.nasa.gov/centers/goddard/news/topstory/2006/little_red_spot.html |url-status=live }}</ref><ref>{{cite journal | title=Vertical structure of Jupiter's Oval BA before and after it reddened: What changed? | last1=Wong | first1=Michael H. | last2=de Pater | first2=Imke | last3=Asay-Davis | first3=Xylar | last4=Marcus | first4=Philip S. | last5=Go | first5=Christopher Y. | journal=Icarus | volume=215 | issue=1 |pages=211–225 | date=September 2011 | doi=10.1016/j.icarus.2011.06.032 | bibcode=2011Icar..215..211W | url=http://cfd.me.berkeley.edu/wp-content/uploads/2011/08/wong-publlished-1.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://cfd.me.berkeley.edu/wp-content/uploads/2011/08/wong-publlished-1.pdf |archive-date=October 9, 2022 |url-status=live | access-date=April 27, 2022 }}</ref>

In April 2017, a "Great Cold Spot" was discovered in Jupiter's thermosphere at its [[Jupiter's North Pole|north pole]]. This feature is {{cvt|24000|km}} across, {{cvt|12000|km}} wide, and {{convert|200|C-change}} cooler than surrounding material. While this spot changes form and intensity over the short term, it has maintained its general position in the atmosphere for more than 15 years. It may be a giant [[vortex]] similar to the Great Red Spot, and appears to be [[Metastability|quasi-stable]] like the [[Vorticity|vortices]] in Earth's thermosphere. This feature may be formed by interactions between charged particles generated from Io and the strong magnetic field of Jupiter, resulting in a redistribution of heat flow.<ref name="Stallard et Al., 2017">{{cite journal |last1=Stallard |first1=Tom S. |last2=Melin |first2=Henrik |last3=Miller |first3=Steve |last4=Moore |first4=Luke |last5=O'Donoghue |first5=James |last6=Connerney |first6=John E. P. |last7=Satoh |first7=Takehiko |last8=West |first8=Robert A. |last9=Thayer |first9=Jeffrey P. |last10=Hsu |first10=Vicki W. |last11=Johnson |first11=Rosie E. |date=April 10, 2017 |title=The Great Cold Spot in Jupiter's upper atmosphere |journal=Geophysical Research Letters |volume=44 |issue=7 |pages=3000–3008 |bibcode=2017GeoRL..44.3000S |doi=10.1002/2016GL071956 |pmc=5439487 |pmid=28603321}}</ref>

=== Magnetosphere ===
{{Main|Magnetosphere of Jupiter}}
[[File:Jupiter's magnetosphere in the vicinity of the Galilean satellites.jpg|thumb|upright=1.5|The [[Galilean moons]]'s affect on Jupiter's magnetosphere]]
Jupiter's [[magnetic field]] is the strongest of any planet in the Solar System,<ref name="worldbook"/> with a [[magnetic dipole moment|dipole moment]] of {{convert|4.170|G|mT|lk=on}} that is tilted at an angle of 10.31° to the pole of rotation. The surface magnetic field strength varies from {{convert|2|G|mT}} up to {{convert|20|G|mT}}.<ref>{{Cite journal |last1=Connerney |first1=J. E. P. |last2=Kotsiaros |first2=S. |last3=Oliversen |first3=R. J. |last4=Espley |first4=J. R. |last5=Joergensen |first5=J. L. |last6=Joergensen |first6=P. S. |last7=Merayo |first7=J. M. G. |last8=Herceg |first8=M. |last9=Bloxham |first9=J. |last10=Moore |first10=K. M. |last11=Bolton |first11=S. J. |last12=Levin |first12=S. M. |date=May 26, 2017 |title=A New Model of Jupiter's Magnetic Field From Juno's First Nine Orbits |url=http://orbit.dtu.dk/ws/files/147221632/Connerney_et_al_2018_Geophysical_Research_Letters.pdf |url-status=live |journal=Geophysical Research Letters |language=en |volume=45 |issue=6 |pages=2590–2596 |bibcode=2018GeoRL..45.2590C |doi=10.1002/2018GL077312 |archive-url=https://ghostarchive.org/archive/20221009/http://orbit.dtu.dk/ws/files/147221632/Connerney_et_al_2018_Geophysical_Research_Letters.pdf |archive-date=October 9, 2022 |doi-access=free}}</ref> This field is thought to be generated by [[eddy current]]s—swirling movements of conducting materials—within the fluid, metallic hydrogen core. At about 75 Jupiter radii from the planet, the interaction of the magnetosphere with the [[solar wind]] generates a [[bow shock]]. Surrounding Jupiter's magnetosphere is a [[magnetopause]], located at the inner edge of a [[magnetosheath]]—a region between it and the bow shock. The solar wind interacts with these regions, elongating the magnetosphere on Jupiter's [[lee side]] and extending it outward until it nearly reaches the orbit of Saturn. The four largest moons of Jupiter all orbit within the magnetosphere, which protects them from solar wind.<ref name="elkins-tanton"/>{{rp|69}}

The volcanoes on the moon [[Io (moon)|Io]] emit large amounts of [[sulfur dioxide]], forming a gas [[torus]] along its orbit. The gas is [[Ionization|ionized]] in Jupiter's [[magnetosphere]], producing sulfur and oxygen [[ion]]s. They, together with hydrogen ions originating from the atmosphere of Jupiter, form a [[plasma sheet]] in Jupiter's equatorial plane. The plasma in the sheet co-rotates with the planet, causing deformation of the dipole magnetic field into that of a magnetodisk. Electrons within the plasma sheet generate a strong radio signature, with short, superimposed bursts in the range of 0.6–30&nbsp;[[hertz|MHz]] that are detectable from Earth with consumer-grade [[shortwave radio receiver]]s.<ref>{{cite news |last=Brainerd |first=Jim |date=November 22, 2004 |title=Jupiter's Magnetosphere |work=The Astrophysics Spectator |url=http://www.astrophysicsspectator.com/topics/planets/JupiterMagnetosphere.html |access-date=August 10, 2008 |archive-date=January 25, 2021 |archive-url=https://web.archive.org/web/20210125004606/https://www.astrophysicsspectator.com/topics/planets/JupiterMagnetosphere.html}}</ref><ref>{{cite web |url=https://radiojove.gsfc.nasa.gov/telescope/rj_receivers.htm |website=NASA |title=Receivers for Radio JOVE |date=March 1, 2017 |access-date=September 9, 2020 |archive-date=January 26, 2021 |archive-url=https://web.archive.org/web/20210126034939/https://radiojove.gsfc.nasa.gov/telescope/rj_receivers.htm |url-status=dead}}</ref> As Io moves through this torus, the interaction generates [[Alfvén wave]]s that carry ionized matter into the polar regions of Jupiter. As a result, radio waves are generated through a [[cyclotron]] [[Astrophysical maser|maser mechanism]], and the energy is transmitted out along a cone-shaped surface. When Earth intersects this cone, the [[Radio wave|radio emissions]] from Jupiter can exceed the radio output of the Sun.<ref>{{cite web |date=February 20, 2004 |url=https://science.nasa.gov/headlines/y2004/20feb_radiostorms.htm |title=Radio Storms on Jupiter |last1=Phillips |first1=Tony |last2=Horack |first2=John M. |website=NASA |access-date=February 1, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20070213220639/https://science.nasa.gov/headlines/y2004/20feb_radiostorms.htm |archive-date=February 13, 2007}}</ref>

=== Planetary rings ===
{{Main|Rings of Jupiter}}
[[File:Jupiter Showcases Auroras, Hazes (NIRCam Widefield View) (jupiter-auroras2).jpeg|thumb|alt=Image of Jupiter showing its faint rings, two small moons, auroras, and atmospheric features.|Jupiter, taken in [[infrared]] light, showing its faint rings, along with two moons – [[Amalthea (moon)|Amalthea]] and [[Adrastea (moon)|Adrastea]], auroras, and atmospheric features.
]]
Jupiter has a faint [[planetary ring]] system composed of three main segments: an inner [[torus]] of particles known as the halo, a relatively bright main ring, and an outer gossamer ring.<ref>{{cite journal |last1=Showalter |first1=M. A. |last2=Burns |first2=J. A. |last3=Cuzzi |first3=J. N. |last4=Pollack |first4=J. B. |year=1987 |title=Jupiter's ring system: New results on structure and particle properties |journal=Icarus |volume=69 |issue=3 |pages=458–498 |bibcode=1987Icar...69..458S |doi=10.1016/0019-1035(87)90018-2}}</ref> These rings appear to be made of dust, whereas Saturn's rings are made of ice.<ref name="elkins-tanton"/>{{rp|65}} The main ring is most likely made out of material ejected from the satellites [[Adrastea (moon)|Adrastea]] and [[Metis (moon)|Metis]], which is drawn into Jupiter because of the planet's strong gravitational influence. New material is added by additional impacts.<ref name="Burns1999">{{cite journal |last1=Burns |first1=J. A. |last2=Showalter |first2=M. R. |last3=Hamilton |first3=D. P. |last4=Nicholson |first4=P. D. |last5=de Pater |first5=I. |last6=Ockert-Bell |first6=M. E. |last7=Thomas |first7=P. C. |year=1999 |title=The Formation of Jupiter's Faint Rings |journal=Science |volume=284 |issue=5417 |pages=1146–1150 |bibcode=1999Sci...284.1146B |doi=10.1126/science.284.5417.1146 |pmid=10325220 |s2cid=21272762}}</ref> In a similar way, the moons [[Thebe (moon)|Thebe]] and [[Amalthea (moon)|Amalthea]] are believed to produce the two distinct components of the dusty gossamer ring.<ref name="Burns1999"/> There is evidence of a fourth ring that may consist of collisional debris from Amalthea that is strung along the same moon's orbit.<ref>{{cite journal |last1=Fieseler |first1=P. D. |last2=Adams |first2=O. W. |last3=Vandermey |first3=N. |last4=Theilig |first4=E. E. |last5=Schimmels |first5=K. A. |last6=Lewis |first6=G. D. |last7=Ardalan |first7=S. M. |last8=Alexander |first8=C. J. |year=2004 |title=The Galileo Star Scanner Observations at Amalthea |journal=Icarus |volume=169 |issue=2 |pages=390–401 |bibcode=2004Icar..169..390F |doi=10.1016/j.icarus.2004.01.012}}</ref>

== Orbit and rotation ==
[[File:Jupiter rotation over 3 hours with 11 inch telescope.gif|left|thumb|3-hour timelapse showing rotation of Jupiter and orbital motion of the moons]]
Jupiter is the only planet whose [[barycentre]] with the Sun lies outside the volume of the Sun, though by 7% of the Sun's radius.<ref>{{cite book | last1=Herbst | first1=T. M. | last2=Rix | first2=H.-W. | date=1999 | editor1-last=Guenther | editor1-first=Eike | editor2-last=Stecklum | editor2-first=Bringfried | editor3-last=Klose | editor3-first=Sylvio | chapter=Star Formation and Extrasolar Planet Studies with Near-Infrared Interferometry on the LBT | title=Optical and Infrared Spectroscopy of Circumstellar Matter | series=ASP Conference Series | volume=188 | isbn=978-1-58381-014-9 | pages=341–350 | bibcode=1999ASPC..188..341H | publisher=Astronomical Society of the Pacific | publication-place=San Francisco, Calif. }} – See section 3.4.</ref><ref name="Jupiter-COM-20160730">{{cite book |page=199|title=Newton's Gravity: An Introductory Guide to the Mechanics of the Universe|last1=MacDougal|first1=Douglas W.|date=December 16, 2012|isbn=978-1-4614-5444-1|publisher=Springer New York}}</ref> The average distance between Jupiter and the Sun is {{convert|778|e6km|AU|abbr=unit}} and it completes an orbit every 11.86&nbsp;years. This is approximately two-fifths the orbital period of Saturn, forming a near [[orbital resonance]].<ref>{{cite journal | last1=Michtchenko | first1=T. A. | last2=Ferraz-Mello | first2=S. | title=Modeling the 5:2 Mean-Motion Resonance in the Jupiter–Saturn Planetary System | journal=Icarus | date=February 2001 | volume=149 | issue=2 | pages=77–115 | doi=10.1006/icar.2000.6539 | bibcode=2001Icar..149..357M }}</ref> The [[orbital plane]] of Jupiter is [[orbital inclination|inclined]] 1.30° compared to Earth. Because the [[Orbital eccentricity|eccentricity]] of its orbit is 0.049, Jupiter is slightly over 75&nbsp;million&nbsp;km nearer the Sun at [[perihelion]] than [[aphelion]],<ref name="fact"/> which means that its orbit is nearly circular. This low eccentricity is at odds with [[exoplanet]] discoveries, which have revealed Jupiter-sized planets with very high eccentricities. Models suggest this may be due to there being two giant planets in the Solar System, as the presence of a third or more giant planets tends to induce larger eccentricities.<ref>{{cite web|title=Simulations explain giant exoplanets with eccentric, close-in orbits|date=October 30, 2019|url=https://www.sciencedaily.com/releases/2019/10/191030132730.htm|publisher=ScienceDaily|access-date=July 17, 2023|archive-date=July 17, 2023|archive-url=https://web.archive.org/web/20230717181409/https://www.sciencedaily.com/releases/2019/10/191030132730.htm#:~:text=Surprisingly%2C%20the%20planets%20with%20the,budge%20from%20its%20initial%20orbit.|url-status=live}}</ref>

The [[axial tilt]] of Jupiter is 3.13°, which is relatively small, so its seasons are insignificant compared to those of Earth and Mars.<ref>{{cite web |url=https://science.nasa.gov/headlines/y2000/interplanetaryseasons.html |title=Interplanetary Seasons |publisher=Science@NASA |access-date=February 20, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20071016161443/https://science.nasa.gov/headlines/y2000/interplanetaryseasons.html |archive-date=October 16, 2007 }}</ref>

Jupiter's [[Period of revolution|rotation]] is the fastest of all the Solar System's planets, completing a rotation on its [[Coordinate axis|axis]] in slightly less than ten hours; this creates an [[equatorial bulge]] easily seen through an amateur telescope. Because Jupiter is not a solid body, its upper atmosphere undergoes [[differential rotation]]. The rotation of Jupiter's polar atmosphere is about five minutes longer than that of the equatorial atmosphere.<ref name="Ridpath1998">{{cite book |last=Ridpath |first=Ian |author-link=Ian Ridpath |title=Norton's Star Atlas |date=1998 |publisher=Prentice Hall |isbn=978-0-582-35655-9 |edition=19th}}{{page needed|date=May 2015}}</ref> The planet is an oblate spheroid, meaning that the diameter across its [[equator]] is longer than the diameter measured between its [[geographic pole|poles]].<ref name="lang03"/> On Jupiter, the equatorial diameter is {{cvt|9276|km|0}} longer than the polar diameter.<ref name="fact"/>

Three systems are used as frames of reference for tracking planetary rotation, particularly when graphing the motion of atmospheric features. System I applies to latitudes from 7°&nbsp;N to 7°&nbsp;S; its period is the planet's shortest, at 9h&nbsp;50&nbsp;m&nbsp;30.0s. System II applies at latitudes north and south of these; its period is 9h&nbsp;55&nbsp;m&nbsp;40.6s.<ref name=Hide1981>{{cite journal | title=On the rotation of Jupiter | last=Hide | first=R. | journal=Geophysical Journal | volume=64 | pages=283–289 | date=January 1981 | doi=10.1111/j.1365-246X.1981.tb02668.x | bibcode=1981GeoJ...64..283H | doi-access=free }}</ref> System III was defined by [[radio astronomer]]s and corresponds to the rotation of the planet's magnetosphere; its period is Jupiter's official rotation.<ref>{{cite journal | title=The rotation period of Jupiter | last1=Russell | first1=C. T. | last2=Yu | first2=Z. J. | last3=Kivelson | first3=M. G. | journal=Geophysical Research Letters | volume=28 | issue=10 | pages=1911–1912 | date=2001 | doi=10.1029/2001GL012917 | bibcode=2001GeoRL..28.1911R | s2cid=119706637 | url=http://www.igpp.ucla.edu/public/mkivelso/Publications/245-2001GL012917.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.igpp.ucla.edu/public/mkivelso/Publications/245-2001GL012917.pdf |archive-date=October 9, 2022 |url-status=live | access-date=April 28, 2022 }}</ref>

== Observation ==
[[File:Jupiter-and-its-moons-amateur.jpg|alt=see caption|thumb|Jupiter and four Galilean moons seen through an amateur telescope]]
Jupiter is usually the [[List of brightest natural objects in the sky|fourth-brightest object in the sky]] (after the Sun, the [[Moon]], and [[Venus]]),<ref name="worldbook"/> although at opposition [[Mars#Viewing from Earth|Mars]] can appear brighter than Jupiter. Depending on Jupiter's position with respect to the Earth, it can vary in visual magnitude from as bright as −2.94 at [[Opposition (astronomy)|opposition]] down to −1.66 during [[conjunction (astronomy and astrology)|conjunction]] with the Sun.<ref name="Mallama_and_Hilton"/> The mean [[apparent magnitude]] is −2.20 with a standard deviation of 0.33.<ref name="Mallama_and_Hilton"/> The [[angular diameter]] of Jupiter likewise varies from 50.1 to 30.5 [[arc second]]s.<ref name="fact"/> Favourable oppositions occur when Jupiter is passing through the [[Apsis|perihelion]] of its orbit, bringing it closer to Earth.<ref>{{cite book|chapter=Appendix 3|title=The giant planet Jupiter|last1=Rogers|first1=John H.|date=July 20, 1995|publisher=Cambridge University Press|isbn=978-0-521-41008-3}}</ref> Near opposition, Jupiter will appear to go into [[Apparent retrograde motion|retrograde motion]] for a period of about 121 days, moving backward through an angle of 9.9° before returning to prograde movement.<ref>{{cite book
 | title=The Planet Observer's Handbook
 | first=Fred W.
 | last=Price
 | date=October 26, 2000
| page=140
 | isbn=978-0-521-78981-3
 | publisher=Cambridge University Press
 | url=https://books.google.com/books?id=GnrAVhVZ3wMC&pg=PA140
 | access-date=March 19, 2023
| archive-date=March 26, 2023
| archive-url=https://web.archive.org/web/20230326164802/https://books.google.com/books?id=GnrAVhVZ3wMC&pg=PA140
 | url-status=live
 }}</ref>

Because the orbit of Jupiter is outside that of Earth, the [[Phase angle (astronomy)|phase angle]] of Jupiter as viewed from Earth is always less than 11.5°; thus, Jupiter always appears nearly fully illuminated when viewed through Earth-based telescopes. It was during spacecraft missions to Jupiter that crescent views of the planet were obtained.<ref>{{cite book
 | title=Pioneer Odyssey
 | url=https://history.nasa.gov/SP-349/sp349.htm
 | first1=Richard O.
 | last1=Fimmel
 | first2=William
 | last2=Swindell
 | first3=Eric
 | last3=Burgess
 | year=1974
 | edition=Revised
 | chapter-url=https://history.nasa.gov/SP-349/ch8.htm
 | chapter=8. Encounter with the Giant
 | publisher=NASA History Office
 | access-date=February 17, 2007
| archive-date=December 25, 2017
| archive-url=https://web.archive.org/web/20171225230634/https://history.nasa.gov/SP-349/sp349.htm
 | url-status=live
 }}</ref> A small telescope will usually show Jupiter's four [[Galilean moons]] and the cloud belts across [[Atmosphere of Jupiter|Jupiter's atmosphere]]. A larger telescope with an aperture of {{convert|4|-|6|in|cm|0|abbr=out}} will show Jupiter's Great Red Spot when it faces Earth.<ref>{{cite book | title=Outer Planets | page=47 | first=Glenn F. | last=Chaple | date=2009 | isbn=978-0-313-36571-3 | publisher=ABC-CLIO | series=Greenwood Guides to the Universe | editor1-first=Lauren V. | editor1-last=Jones | editor2-first=Timothy F. | editor2-last=Slater | url=https://books.google.com/books?id=6KXACQAAQBAJ&pg=PA47 | access-date=March 19, 2023 | archive-date=March 26, 2023 | archive-url=https://web.archive.org/web/20230326164803/https://books.google.com/books?id=6KXACQAAQBAJ&pg=PA47 | url-status=live }}</ref><ref>{{cite book
 | title=The Sky at Night: How to Read the Solar System
 | last1=North | first1=Chris | last2=Abel | first2=Paul
 | date=October 31, 2013 | page=183
 | publisher=Ebury Publishing | isbn=978-1-4481-4130-2
}}</ref>

=== History ===

==== Pre-telescopic research ====
[[File:Almagest-planets.svg|thumb|left|Model in the ''[[Almagest]]'' of the longitudinal motion of Jupiter (☉) relative to Earth (🜨)|upright=1.2]]
Observations of Jupiter are attested with the [[Babylonian astronomers]] during the 7th–8th centuries&nbsp;BC.<ref>{{Cite journal |title=Babylonian Observational Astronomy |last=Sachs |first=A. |journal=[[Philosophical Transactions of the Royal Society of London]] |volume=276 |issue=1257 |date=May 2, 1974 |pages=43–50 (see p. 44) |jstor=74273 |doi=10.1098/rsta.1974.0008 |bibcode=1974RSPTA.276...43S|s2cid=121539390 }}</ref> The ancient Chinese knew Jupiter as the '{{tlit|zh|sui}} star' ({{transliteration|zh|Suìxīng}} {{lang|zh|歲星}})<!--not year star--> and established their cycle of twelve [[earthly branches]] based on the approximate number of years it takes Jupiter to revolve around the Sun; the [[Chinese language]] still uses its name ({{lang|zh|歲}}; [[simplified characters|simplified]] as {{lang|zh|岁}}) when referring to years of age. By the 4th century&nbsp;BC, these observations had developed into the [[Chinese zodiac]],<ref name=Homer>{{cite journal |first=Homer H. |last=Dubs |author-link=Homer H. Dubs |title=The Beginnings of Chinese Astronomy |journal=Journal of the American Oriental Society |volume=78 |number=4 |year=1958 |pages=295–300 |doi=10.2307/595793 |jstor=595793 }}</ref> and each year became associated with a [[Tai Sui]] star and [[Chinese gods|god]] controlling the region of the heavens opposite Jupiter's position in the night sky. These beliefs survive in some [[Taoist]] and [[Chinese folk religion|folk religious practices]] and in the East Asian zodiac's twelve animals. The Chinese historian [[Xi Zezong]] has claimed that [[Gan De]], an ancient [[Chinese astronomy|Chinese astronomer]],<ref>{{cite book | title=A Guide to Hubble Space Telescope Objects: Their Selection, Location, and Significance | first1=James L. | last1=Chen | first2=Adam | last2=Chen | date=2015 | page=195 | isbn=978-3-319-18872-0 | publisher=Springer International Publishing | url=https://books.google.com/books?id=qj0wCgAAQBAJ&pg=PA195 | access-date=March 19, 2023 | archive-date=March 26, 2023 | archive-url=https://web.archive.org/web/20230326164802/https://books.google.com/books?id=qj0wCgAAQBAJ&pg=PA195 | url-status=live }}</ref> reported a small star "in alliance" with the planet,<ref>{{cite book | chapter=Facts, Fallacies, Unusual Observations, and Other Miscellaneous Gleanings | title=Weird Astronomy: Tales of Unusual, Bizarre, and Other Hard to Explain Observations | first=David A. J. | last=Seargent | pages=221–282 | isbn=978-1-4419-6424-3 | series=Astronomers' Universe | date=September 24, 2010 }}</ref> which may indicate a sighting of one of [[Moons of Jupiter|Jupiter's moons]] with the unaided eye. If true, this would predate Galileo's discovery by nearly two millennia.<ref>{{cite journal |last=Xi |first=Z. Z. |title=The Discovery of Jupiter's Satellite Made by Gan-De 2000 Years Before Galileo |journal=Acta Astrophysica Sinica |year=1981 |volume=1 |issue=2 |page=87 |bibcode=1981AcApS...1...85X}}</ref><ref>{{cite book |first=Paul |last=Dong |date=2002 |title=China's Major Mysteries: Paranormal Phenomena and the Unexplained in the People's Republic |publisher=China Books |isbn=978-0-8351-2676-2}}</ref>

A 2016 paper reports that [[trapezoidal rule]] was used by [[Babylon]]ians before 50 BC for integrating the velocity of Jupiter along the [[ecliptic]].<ref>{{cite journal |last=Ossendrijver |first=Mathieu |date=January 29, 2016 |title=Ancient Babylonian astronomers calculated Jupiter's position from the area under a time-velocity graph |journal=Science |doi=10.1126/science.aad8085 |pmid=26823423 |volume=351 |issue=6272 |pages=482–484 |bibcode=2016Sci...351..482O |s2cid=206644971 |url=https://www.science.org/doi/full/10.1126/science.aad8085 |access-date=June 30, 2022 |archive-date=August 1, 2022 |archive-url=https://web.archive.org/web/20220801135608/https://www.science.org/doi/full/10.1126/science.aad8085 |url-status=live |url-access=subscription }}</ref> In his 2nd century work the ''[[Almagest]]'', the Hellenistic astronomer [[Claudius Ptolemaeus]] constructed a [[geocentric]] planetary model based on [[deferent]]s and [[epicycle]]s to explain Jupiter's motion relative to Earth, giving its orbital period around Earth as 4332.38&nbsp;days, or 11.86&nbsp;years.<ref>{{cite book |last=Pedersen |first=Olaf |title=A Survey of the Almagest|date=1974 |publisher=Odense University Press |isbn=9788774920878 |pages=423, 428}}</ref>

==== Ground-based telescope research ====
[[File:Medicean Stars.png|thumb|Galileo's drawings of Jupiter and its "Medicean Stars" from ''[[Sidereus Nuncius]]''|339x339px]]
In 1610, Italian polymath [[Galileo Galilei]] discovered the four largest moons of Jupiter (now known as the [[Galilean moons]]) using a telescope. This is thought to be the first telescopic observation of moons other than Earth's. Just one day after Galileo, [[Simon Marius]] independently discovered moons around Jupiter, though he did not publish his discovery in a book until 1614.<ref>{{cite journal | last=Pasachoff | first=Jay M. |title=Simon Marius's Mundus Iovialis: 400th Anniversary in Galileo's Shadow |journal=Journal for the History of Astronomy |year=2015 |volume=46 |issue=2 |pages=218–234 |bibcode=2015AAS...22521505P |doi=10.1177/0021828615585493|s2cid=120470649 }}</ref> It was Marius's names for the major moons, however, that stuck: Io, Europa, Ganymede, and Callisto. The discovery was a major point in favour of the [[heliocentrism|heliocentric]] theory of the motions of the planets by [[Nicolaus Copernicus]]; Galileo's outspoken support of the Copernican theory led to him being tried and condemned by the [[Inquisition]].<ref>{{cite web | last=Westfall | first=Richard S. | url=http://galileo.rice.edu/Catalog/NewFiles/galilei_gal.html | title=Galilei, Galileo | work=The Galileo Project | publisher=Rice University | access-date=January 10, 2007 | archive-date=January 23, 2022 | archive-url=https://web.archive.org/web/20220123185902/http://galileo.rice.edu/Catalog/NewFiles/galilei_gal.html | url-status=live }}</ref>

In the autumn of 1639, the Neapolitan optician Francesco Fontana tested a 22-palm telescope of his own making and discovered the characteristic bands of the planet's atmosphere.<ref>{{cite journal | first1=Paolo | last1=Del Santo | first2=Leo S. | last2=Olschki | title=On an Unpublished Letter of Francesco Fontana to the Grand-Duke of Tuscany Ferdinand II de' Medici | journal=Galilæana: Journal of Galilean Studies | volume=VI | year=2009 | pages=1000–1017 | url=https://www.torrossa.com/en/resources/an/2242254 | access-date=November 14, 2023 | archive-date=November 15, 2023 | archive-url=https://web.archive.org/web/20231115042550/https://www.torrossa.com/en/resources/an/2242254 | url-status=live }} {{URL| 1=https://bibdig.museogalileo.it/tecanew/opera?bid=917416_6&seq=246} | 2=Alternate URL }}</ref>

During the 1660s, [[Giovanni Domenico Cassini|Giovanni Cassini]] used a new telescope to discover spots in Jupiter's atmosphere, observe that the planet appeared oblate, and estimate its rotation period.<ref name="cassini1">{{cite web | last1=O'Connor | first1=J. J. | last2=Robertson | first2=E. F. | date=April 2003 | url=http://www-history.mcs.st-andrews.ac.uk/Biographies/Cassini.html | title=Giovanni Domenico Cassini | publisher=University of St. Andrews | access-date=February 14, 2007 | archive-date=July 7, 2015 | archive-url=https://web.archive.org/web/20150707025018/http://www-history.mcs.st-andrews.ac.uk/Biographies/Cassini.html | url-status=live }}</ref> In 1692, Cassini noticed that the atmosphere undergoes a differential rotation.<ref>{{cite journal
 | title=The Galileo probe Doppler wind experiment: Measurement of the deep zonal winds on Jupiter
 | last1=Atkinson | first1=David H. | last2=Pollack | first2=James B. | last3=Seiff | first3=Alvin
 | journal=Journal of Geophysical Research
 | volume=103 | issue=E10 | pages=22911–22928 | date=September 1998
 | doi=10.1029/98JE00060 | bibcode=1998JGR...10322911A | doi-access=free }}</ref>

The Great Red Spot may have been observed as early as 1664 by [[Robert Hooke]] and in 1665 by Cassini, although this is disputed. The pharmacist [[Samuel Heinrich Schwabe|Heinrich Schwabe]] produced the earliest known drawing to show details of the Great Red Spot in 1831.<ref>{{cite book |first=Paul |last=Murdin |date=2000 |title=Encyclopedia of Astronomy and Astrophysics |publisher=Institute of Physics Publishing |location=Bristol |isbn=978-0-12-226690-4 |url-access=registration |url=https://archive.org/details/encyclopediaofas0000unse_w5z7 }}</ref> The Red Spot was reportedly lost from sight on several occasions between 1665 and 1708 before becoming quite conspicuous in 1878.<ref>{{cite book
 | title=The giant planet Jupiter
 | first=John H.
 | last=Rogers
 | date=1995
 | pages=188–189
 | isbn=978-0-521-41008-3
 | publisher=Cambridge University Press
 | url=https://books.google.com/books?id=SO48AAAAIAAJ&pg=PA188
 | access-date=March 19, 2023
| archive-date=March 26, 2023
| archive-url=https://web.archive.org/web/20230326164803/https://books.google.com/books?id=SO48AAAAIAAJ&pg=PA188
 | url-status=live
 }}</ref> It was recorded as fading again in 1883 and at the start of the 20th century.<ref>{{cite book | edition=Revised | first1=Richard O. | last1=Fimmel | first2=William | last2=Swindell | first3=Eric | last3=Burgess | date=August 1974 | chapter-url=https://history.nasa.gov/SP-349/ch1.htm | chapter=Jupiter, Giant of the Solar System | title=Pioneer Odyssey | publisher=NASA History Office | access-date=August 10, 2006 | archive-date=August 23, 2006 | archive-url=https://web.archive.org/web/20060823034429/http://history.nasa.gov/SP-349/ch1.htm | url-status=live }}</ref>

Both [[Giovanni Alfonso Borelli|Giovanni Borelli]] and Cassini made careful tables of the motions of Jupiter's moons, which allowed predictions of when the moons would pass before or behind the planet. By the 1670s, Cassini observed that when Jupiter was on the opposite side of the Sun from Earth, these events would occur about 17&nbsp;minutes later than expected. [[Ole Rømer]] deduced that light does not travel instantaneously (a conclusion that Cassini had earlier rejected),<ref name="cassini"/> and this timing discrepancy was used to estimate the [[speed of light]].<ref>{{cite web | first=Kevin | last=Brown | date=2004 | url=http://www.mathpages.com/home/kmath203/kmath203.htm | title=Roemer's Hypothesis | publisher=MathPages | access-date=January 12, 2007 | archive-date=September 6, 2012 | archive-url=https://archive.today/20120906031735/http://www.mathpages.com/home/kmath203/kmath203.htm | url-status=live }}</ref><ref>{{cite journal
 | title=Cassini, Rømer, and the velocity of light
 | last1=Bobis | first1=Laurence | last2=Lequeux | first2=James
 | journal=Journal of Astronomical History and Heritage
 | volume=11 | issue=2 | pages=97–105
 | date=July 2008 | doi=10.3724/SP.J.1440-2807.2008.02.02 | bibcode=2008JAHH...11...97B | s2cid=115455540 }}</ref>

In 1892, [[E. E. Barnard]] observed a fifth satellite of Jupiter with the {{convert|36|in|adj=on}} refractor at [[Lick Observatory]] in California. This moon was later named [[Amalthea (moon)|''Amalthea'']].<ref>{{cite web |first=Joe |last=Tenn |date=March 10, 2006 |url=http://www.phys-astro.sonoma.edu/BruceMedalists/Barnard/ |title=Edward Emerson Barnard |publisher=Sonoma State University |access-date=January 10, 2007 |archive-date=September 17, 2011 |archive-url=https://web.archive.org/web/20110917023559/http://www.phys-astro.sonoma.edu/BruceMedalists/Barnard/ |url-status=dead }}</ref> It was the last planetary moon to be discovered directly by a visual observer through a telescope.<ref>{{cite web |date=October 1, 2001 |url=http://www2.jpl.nasa.gov/galileo/education/teacherres-amalthea.html |archive-url=https://web.archive.org/web/20011124022331/http://www.jpl.nasa.gov/galileo/education/teacherres-amalthea.html |url-status=dead |archive-date=November 24, 2001 |title=Amalthea Fact Sheet |publisher=NASA/JPL |access-date=February 21, 2007}}</ref> An additional eight satellites were discovered before the flyby of the ''[[Voyager 1]]'' probe in 1979.{{refn |group=lower-alpha |See [[Moons of Jupiter]] for details and cites}}

In 1932, [[Rupert Wildt]] identified [[absorption bands]] of ammonia and methane in the spectra of Jupiter.<ref>{{cite journal |last=Dunham |first=Theodore Jr. |year=1933 |title=Note on the Spectra of Jupiter and Saturn |journal=Publications of the Astronomical Society of the Pacific |volume=45 |issue=263 |pages=42–44 |bibcode=1933PASP...45...42D |doi=10.1086/124297 |doi-access=free}}</ref> Three long-lived anticyclonic features called "white ovals" were observed in 1938. For several decades, they remained as separate features in the atmosphere that approach each other but never merge. Finally, two of the ovals merged in 1998, then absorbed the third in 2000, becoming [[Oval BA]].<ref>{{cite journal | last1=Youssef | first1=A. | last2=Marcus | first2=P. S. | title=The dynamics of jovian white ovals from formation to merger | journal=Icarus | year=2003 | volume=162 | issue=1 | pages=74–93 | bibcode=2003Icar..162...74Y | doi=10.1016/S0019-1035(02)00060-X }}</ref>

==== Radiotelescope research ====
In 1955, Bernard Burke and [[Kenneth Franklin]] discovered that Jupiter emits bursts of radio waves at a frequency of 22.2&nbsp;MHz.<ref name="elkins-tanton"/>{{rp|36}} The period of these bursts matched the rotation of the planet, and they used this information to determine a more precise value for Jupiter's rotation rate. Radio bursts from Jupiter were found to come in two forms: long bursts (or L-bursts) lasting up to several seconds, and short bursts (or S-bursts) lasting less than a hundredth of a second.<ref>{{cite web |last=Weintraub |first=Rachel A. |date=September 26, 2005 |url=http://www.nasa.gov/vision/universe/solarsystem/radio_jupiter.html |title=How One Night in a Field Changed Astronomy |publisher=NASA |access-date=February 18, 2007 |archive-date=July 3, 2011 |archive-url=https://web.archive.org/web/20110703080812/http://www.nasa.gov/vision/universe/solarsystem/radio_jupiter.html |url-status=dead }}</ref>

Scientists have discovered three forms of radio signals transmitted from Jupiter:
* Decametric radio bursts (with a wavelength of tens of metres) vary with the rotation of Jupiter, and are influenced by the interaction of Io with Jupiter's magnetic field.<ref>{{cite web |last=Garcia |first=Leonard N |url=http://radiojove.gsfc.nasa.gov/library/sci_briefs/decametric.htm |title=The Jovian Decametric Radio Emission |publisher=NASA |access-date=February 18, 2007 |archive-date=March 2, 2012 |archive-url=https://web.archive.org/web/20120302222737/http://radiojove.gsfc.nasa.gov/library/sci_briefs/decametric.htm |url-status=live }}</ref>
* Decimetric radio emission (with wavelengths measured in centimetres) was first observed by [[Frank Drake]] and Hein Hvatum in 1959.<ref name="elkins-tanton"/>{{rp|36}} The origin of this signal is a torus-shaped belt around Jupiter's equator, which generates [[cyclotron radiation]] from electrons that are accelerated in Jupiter's magnetic field.<ref>{{cite journal | last1=Klein | first1=M. J. | last2=Gulkis | first2=S. | last3=Bolton | first3=S. J. | year=1996 | url=https://ntrs.nasa.gov/search.jsp?R=20060036302 | title=Jupiter's Synchrotron Radiation: Observed Variations Before, During and After the Impacts of Comet SL9 | journal=Conference at University of Graz | page=217 | publisher=NASA | access-date=February 18, 2007 | bibcode=1997pre4.conf..217K | archive-date=November 17, 2015 | archive-url=https://web.archive.org/web/20151117143101/http://ntrs.nasa.gov/search.jsp?R=20060036302 | url-status=live }}</ref>
* [[Thermal radiation]] is produced by heat in the atmosphere of Jupiter.<ref name="elkins-tanton"/>{{rp|43}}

==== Exploration ====
{{Main|Exploration of Jupiter}}

Jupiter has been visited by automated [[spacecraft]] since 1973, when the space probe ''[[Pioneer 10]]'' passed close enough to Jupiter to send back revelations about its properties and phenomena.<ref>{{cite web | url=https://www.nasa.gov/centers/ames/missions/archive/pioneer.html | title=The Pioneer Missions | publisher=NASA | date=March 26, 2007 | access-date=February 26, 2021 | archive-date=December 23, 2018 | archive-url=https://web.archive.org/web/20181223151213/https://www.nasa.gov/centers/ames/missions/archive/pioneer.html | url-status=live }}</ref><ref>{{cite web | title=NASA Glenn Pioneer Launch History | date=March 7, 2003 | url=http://www.nasa.gov/centers/glenn/about/history/pioneer.html | publisher=NASA – Glenn Research Center | access-date=December 22, 2011 | archive-date=July 13, 2017 | archive-url=https://web.archive.org/web/20170713041117/https://www.nasa.gov/centers/glenn/about/history/pioneer.html | url-status=dead }}</ref> Missions to Jupiter are accomplished at a cost in energy, which is described by the net change in velocity of the spacecraft, or [[delta-v]]. Entering a [[Hohmann transfer orbit]] from Earth to Jupiter from [[low Earth orbit]] requires a delta-v of 6.3&nbsp;km/s,<ref>{{cite book | last1=Fortescue | first1=Peter W. | last2=Stark | first2=John | last3=Swinerd | first3=Graham | title=Spacecraft systems engineering | edition=3rd | publisher=John Wiley and Sons | year=2003 | isbn=978-0-470-85102-9 | page=150 }}</ref> which is comparable to the 9.7&nbsp;km/s delta-v needed to reach low Earth orbit.<ref>{{cite web
 | last=Hirata | first=Chris
 | url=http://www.pma.caltech.edu/~chirata/deltav.html
 | title=Delta-V in the Solar System
 | publisher=California Institute of Technology |access-date=November 28, 2006
| archive-url=https://web.archive.org/web/20060715015836/http://www.pma.caltech.edu/~chirata/deltav.html
 | archive-date=July 15, 2006 |url-status=dead
}}</ref> [[Gravitational slingshot|Gravity assists]] through planetary [[Gravitational slingshot|flybys]] can be used to reduce the energy required to reach Jupiter.<ref name="delta-v">{{cite web |last=Wong |first=Al |date=May 28, 1998 |url=http://www2.jpl.nasa.gov/galileo/faqnav.html |archive-url=https://web.archive.org/web/19970105184300/http://www.jpl.nasa.gov/galileo/faqnav.html |url-status=dead |archive-date=January 5, 1997 |title=Galileo FAQ: Navigation |publisher=NASA |access-date=November 28, 2006}}</ref>

===== Flyby missions =====
{| class="wikitable floatright"
|+
|-
! Spacecraft
! Closest<br/>approach
! Distance (km)
|-
| ''[[Pioneer 10]]''
| December 3, 1973
| style="text-align: right;" | 130,000
|-
| ''[[Pioneer 11]]''
| December 4, 1974
| style="text-align: right;" | 34,000
|-
| ''[[Voyager 1]]''
| March 5, 1979
| style="text-align: right;" | 349,000
|-
| ''[[Voyager 2]]''
| July 9, 1979
| style="text-align: right;" | 570,000
|-
| rowspan="2" | ''[[Ulysses probe|Ulysses]]''
| February 8, 1992<ref name="ulysses"/>
| style="text-align: right;" | 408,894
|-
| February 4, 2004<ref name="ulysses"/>
| style="text-align: right;" | 120,000,000
|-
| ''[[Cassini–Huygens|Cassini]]''
| December 30, 2000
| style="text-align: right;" | 10,000,000
|-
| ''[[New Horizons]]''
| February 28, 2007
| style="text-align: right;" | 2,304,535
|}

Beginning in 1973, several spacecraft performed planetary flyby manoeuvres that brought them within the observation range of Jupiter. The [[Pioneer program|Pioneer]] missions obtained the first close-up images of Jupiter's atmosphere and several of its moons. They discovered that the radiation fields near the planet were much stronger than expected, but both spacecraft managed to survive in that environment. The trajectories of these spacecraft were used to refine the mass estimates of the [[Moons of Jupiter|Jovian system]]. [[Radio occultations]] by the planet resulted in better measurements of Jupiter's diameter and the amount of polar flattening.<ref name="burgess"/>{{rp|47}}<ref name="cosmology 101">{{cite web |last=Lasher |first=Lawrence |date=August 1, 2006 |url=http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNhome.html |title=Pioneer Project Home Page |publisher=NASA Space Projects Division |access-date=November 28, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060101001205/http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNhome.html |archive-date=January 1, 2006 }}</ref>

Six years later, the [[Voyager program|Voyager]] missions vastly improved the understanding of the [[Galilean moons]] and discovered Jupiter's rings. They also confirmed that the Great Red Spot was anticyclonic. Comparison of images showed that the Spot had changed hues since the Pioneer missions, turning from orange to dark brown. A torus of ionized atoms was discovered along Io's orbital path, which were found to come from erupting volcanoes on the moon's surface. As the spacecraft passed behind the planet, it observed flashes of lightning in the [[Terminator (solar)|night side]] atmosphere.<ref name="burgess"/>{{rp|87}}<ref name="voyager1">{{cite web |date=January 14, 2003 |url=http://voyager.jpl.nasa.gov/science/jupiter.html |title=Jupiter |publisher=NASA/JPL |access-date=November 28, 2006 |archive-date=June 28, 2012 |archive-url=https://web.archive.org/web/20120628073053/http://voyager.jpl.nasa.gov/science/jupiter.html |url-status=live }}</ref>

The next mission to encounter Jupiter was the ''[[Ulysses (spacecraft)|Ulysses]]'' solar probe. In February 1992, it performed a flyby manoeuvre to attain a [[polar orbit]] around the Sun. During this pass, the spacecraft studied Jupiter's magnetosphere, although it had no cameras to photograph the planet. The spacecraft passed by Jupiter six years later, this time at a much greater distance.<ref name="ulysses">{{Cite book | last1=Chan | first1=K. | title=Space OPS 2004 Conference | last2=Paredes | first2=E. S. | last3=Ryne | first3=M. S. | date=2004 | publisher=American Institute of Aeronautics and Astronautics | doi=10.2514/6.2004-650-447 | chapter=Ulysses Attitude and Orbit Operations: 13+ Years of International Cooperation }}</ref>

In 2000, the ''Cassini'' probe flew by Jupiter on its way to Saturn, and provided higher-resolution images.<ref>{{cite journal | last1=Hansen | first1=C. J. | last2=Bolton | first2=S. J. | last3=Matson | first3=D. L. | last4=Spilker | first4=L. J. | last5=Lebreton | first5=J.-P. |title=The Cassini–Huygens flyby of Jupiter |bibcode=2004Icar..172....1H |journal=Icarus |year=2004 |volume=172 |issue=1 |pages=1–8 |doi=10.1016/j.icarus.2004.06.018}}</ref>

The ''[[New Horizons]]'' probe flew by Jupiter in 2007 for a gravity assist en route to [[Pluto]].<ref>{{cite web | url=https://www.nasa.gov/mission_pages/newhorizons/news/nh_jupiter_oct09.html | date=October 9, 2007 | publisher=NASA | title=Pluto-Bound New Horizons Sees Changes in Jupiter System | access-date=February 26, 2021 | archive-date=November 27, 2020 | archive-url=https://web.archive.org/web/20201127014401/http://www.nasa.gov/mission_pages/newhorizons/news/nh_jupiter_oct09.html | url-status=dead }}</ref> The probe's cameras measured plasma output from volcanoes on Io and studied all four Galilean moons in detail.<ref>{{cite web | url=http://www.nasa.gov/mission_pages/newhorizons/news/jupiter_system.html | title=Pluto-Bound New Horizons Provides New Look at Jupiter System | date=May 1, 2007 | publisher=NASA | access-date=July 27, 2007 | archive-date=December 12, 2010 | archive-url=https://web.archive.org/web/20101212052748/http://www.nasa.gov/mission_pages/newhorizons/news/jupiter_system.html | url-status=dead }}</ref>

===== ''Galileo'' mission =====
{{Main|Galileo (spacecraft)}}
[[File:Galileo Preparations - GPN-2000-000672.jpg|left|thumb|''Galileo'' in preparation for mating with the rocket, 1989]]
The first spacecraft to orbit Jupiter was the ''[[Galileo (spacecraft)|Galileo]]'' mission, which reached the planet on December 7, 1995.<ref name="HTUW"/> It remained in orbit for over seven years, conducting multiple flybys of all the Galilean moons and [[Amalthea (moon)|Amalthea]]. The spacecraft also witnessed the impact of [[Comet Shoemaker–Levy 9]] when it collided with Jupiter in 1994. Some of the goals for the mission were thwarted due to a malfunction in ''Galileo''s high-gain antenna.<ref name="galileo">{{cite web |last=McConnell |first=Shannon |date=April 14, 2003 |url=http://solarsystem.nasa.gov/galileo/ |archive-url=https://web.archive.org/web/20041103173530/http://solarsystem.nasa.gov/galileo/ |url-status=dead |archive-date=November 3, 2004 |title=Galileo: Journey to Jupiter |publisher=NASA/JPL |access-date=November 28, 2006}}</ref>

A 340-kilogram titanium [[Galileo (spacecraft)#Galileo entry probe|atmospheric probe]] was released from the spacecraft in July 1995, entering Jupiter's atmosphere on December 7.<ref name="HTUW"/> It parachuted through {{cvt|150|km|0}} of the atmosphere at a speed of about {{cvt|2575|kph}}<ref name="HTUW"/> and collected data for 57.6&nbsp;minutes until the spacecraft was destroyed.<ref>{{cite web |first=Julio |last=Magalhães |date=December 10, 1996 |url=http://spaceprojects.arc.nasa.gov/Space_Projects/galileo_probe/htmls/probe_events.html |title=Galileo Probe Mission Events |publisher=NASA Space Projects Division |access-date=February 2, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20070102143553/http://spaceprojects.arc.nasa.gov/Space_Projects/galileo_probe/htmls/probe_events.html |archive-date=January 2, 2007 }}</ref> The ''Galileo'' orbiter itself experienced a more rapid version of the same fate when it was deliberately steered into the planet on September 21, 2003. [[NASA]] destroyed the spacecraft to avoid any possibility of the spacecraft crashing into and possibly contaminating the moon Europa, [[Life on Europa|which may harbour life]].<ref name="galileo"/>

Data from this mission revealed that hydrogen composes up to 90% of Jupiter's atmosphere.<ref name="HTUW"/> The recorded temperature was more than {{Convert|300|C}}, and the wind speed measured more than 644&nbsp;km/h (>400&nbsp;mph) before the probes vaporized.<ref name="HTUW"/>

===== ''Juno'' mission =====
{{Main|Juno (spacecraft)}}
[[File:Juno prepared for rotation test stand.jpg|alt=see caption|thumb|''Juno'' preparing for testing in a rotation stand, 2011|331x331px]]
NASA's ''[[Juno (spacecraft)|Juno]]'' mission arrived at Jupiter on July 4, 2016, with the goal of studying the planet in detail from a [[polar orbit]]. The spacecraft was originally intended to orbit Jupiter thirty-seven times over a period of twenty months.<ref name="NYT-20160705" /><ref>{{cite web | first=Anthony | last=Goodeill | date=March 31, 2008 | url=http://newfrontiers.nasa.gov/missions_juno.html | title=New Frontiers – Missions – Juno | publisher=NASA | access-date=January 2, 2007 | url-status=dead |archive-url=https://web.archive.org/web/20070203235637/http://newfrontiers.nasa.gov/missions_juno.html | archive-date=February 3, 2007 }}</ref><ref>{{cite web
 | title=Juno, NASA's Jupiter probe
 | publisher=The Planetary Society
 | url=https://www.planetary.org/space-missions/juno
 | access-date=April 27, 2022
| archive-date=May 12, 2022
| archive-url=https://web.archive.org/web/20220512174710/https://www.planetary.org/space-missions/juno
 | url-status=live
 }}</ref> During the mission, the spacecraft will be exposed to high levels of radiation from [[Magnetosphere of Jupiter|Jupiter's magnetosphere]], which may cause the failure of certain instruments.<ref>{{cite web | title=NASA's Juno spacecraft to risk Jupiter's fireworks for science | author=Jet Propulsion Laboratory | date=June 17, 2016 | website=phys.org | url=https://phys.org/news/2016-06-nasa-juno-spacecraft-jupiter-fireworks.html | access-date=April 10, 2022 | archive-date=August 9, 2022 | archive-url=https://web.archive.org/web/20220809222951/https://phys.org/news/2016-06-nasa-juno-spacecraft-jupiter-fireworks.html | url-status=live }}</ref> On August 27, 2016, the spacecraft completed its first flyby of Jupiter and sent back the first-ever images of [[Jupiter's_North_Pole|Jupiter's north pole]].<ref>{{cite web |first=Niall |last=Firth |date=September 5, 2016 |url=https://www.newscientist.com/article/2104558-nasas-juno-probe-snaps-first-images-of-jupiters-north-pole/ |title=NASA's Juno probe snaps first images of Jupiter's north pole |work=New Scientist |access-date=September 5, 2016 |archive-date=September 6, 2016 |archive-url=https://web.archive.org/web/20160906173136/https://www.newscientist.com/article/2104558-nasas-juno-probe-snaps-first-images-of-jupiters-north-pole/ |url-status=live }}</ref>

''Juno'' completed 12 orbits before the end of its budgeted mission plan, ending in July 2018.<ref name="sfnow20170221">{{cite news|url=https://spaceflightnow.com/2017/02/21/nasas-juno-spacecraft-to-remain-in-current-orbit-around-jupiter/|title=NASA's Juno spacecraft to remain in current orbit around Jupiter|publisher=Spaceflight Now|first=Stephen|last=Clark|date=February 21, 2017|access-date=April 26, 2017|archive-date=February 26, 2017|archive-url=https://web.archive.org/web/20170226211013/http://spaceflightnow.com/2017/02/21/nasas-juno-spacecraft-to-remain-in-current-orbit-around-jupiter/|url-status=live}}</ref> In June of that year, NASA extended the mission operations plan to July 2021, and in January of that year the mission was extended to September 2025 with four lunar flybys: one of Ganymede, one of Europa, and two of Io.<ref name="nasa20180606">{{cite web |url=https://www.jpl.nasa.gov/news/news.php?release=2018-130 |title=NASA Re-plans Juno's Jupiter Mission |publisher=NASA/JPL |first1=D. C. |last1=Agle |first2=JoAnna |last2=Wendel |first3=Deb |last3=Schmid |date=June 6, 2018 |access-date=January 5, 2019 |archive-date=July 24, 2020 |archive-url=https://web.archive.org/web/20200724112957/https://www.jpl.nasa.gov/news/news.php?release=2018-130 |url-status=live }}</ref><ref name="nasa20210108">{{Cite web|last=Talbert|first=Tricia|date=January 8, 2021|title=NASA Extends Exploration for Two Planetary Science Missions|url=http://www.nasa.gov/feature/nasa-extends-exploration-for-two-planetary-science-missions|access-date=January 11, 2021|website=NASA|archive-date=January 11, 2021|archive-url=https://web.archive.org/web/20210111161636/https://www.nasa.gov/feature/nasa-extends-exploration-for-two-planetary-science-missions/|url-status=live}}</ref> When ''Juno'' reaches the end of the mission, it will perform a controlled deorbit and disintegrate into Jupiter's atmosphere to avoid the risk of colliding and contaminating Jupiter's moons.<ref name="skytel20170221">{{cite news |url=http://www.skyandtelescope.com/astronomy-news/juno-stay-current-orbit-jupiter/ |title=Juno Will Stay in Current Orbit Around Jupiter |work=Sky & Telescope |first=David |last=Dickinson |date=February 21, 2017 |access-date=January 7, 2018 |archive-date=January 8, 2018 |archive-url=https://web.archive.org/web/20180108063357/http://www.skyandtelescope.com/astronomy-news/juno-stay-current-orbit-jupiter/ |url-status=live }}</ref>

===== Cancelled missions and future plans =====
There is an interest in missions to study Jupiter's larger icy moons, which may have subsurface liquid oceans.<ref>{{Cite web |last=Sori |first=Mike |title=Jupiter's moons hide giant subsurface oceans – two missions are sending spacecraft to see if these moons could support life |url=http://theconversation.com/jupiters-moons-hide-giant-subsurface-oceans-two-missions-are-sending-spacecraft-to-see-if-these-moons-could-support-life-203207 |access-date=May 12, 2023 |website=The Conversation |date=April 10, 2023 |language=en |archive-date=May 12, 2023 |archive-url=https://web.archive.org/web/20230512042246/http://theconversation.com/jupiters-moons-hide-giant-subsurface-oceans-two-missions-are-sending-spacecraft-to-see-if-these-moons-could-support-life-203207 |url-status=live }}</ref> Funding difficulties have delayed progress, causing NASA's ''[[Jupiter Icy Moons Orbiter|JIMO]]'' (''Jupiter Icy Moons Orbiter'') to be cancelled in 2005.<ref>{{cite news |first=Brian |last=Berger |title=White House scales back space plans |publisher=MSNBC |date=February 7, 2005 |url=http://www.nbcnews.com/id/6928404/ |access-date=January 2, 2007 |archive-date=October 29, 2013 |archive-url=https://web.archive.org/web/20131029210930/http://www.nbcnews.com/id/6928404/ |url-status=dead }}</ref> A subsequent proposal was developed for a joint NASA/[[European Space Agency|ESA]] mission called [[EJSM/Laplace]], with a provisional launch date around 2020. EJSM/Laplace would have consisted of the NASA-led [[Jupiter Europa Orbiter]] and the ESA-led [[Jupiter Ganymede Orbiter]].<ref>{{cite web |url=http://sci.esa.int/science-e/www/area/index.cfm?fareaid=107 |title=Laplace: A mission to Europa & Jupiter system |publisher=European Space Agency |access-date=January 23, 2009 |archive-date=July 14, 2012 |archive-url=https://web.archive.org/web/20120714200604/http://sci.esa.int/science-e/www/area/index.cfm?fareaid=107 |url-status=live }}</ref> However, the ESA formally ended the partnership in April 2011, citing budget issues at NASA and the consequences on the mission timetable. Instead, ESA planned to go ahead with a European-only mission to compete in its L1 [[Cosmic Vision]] selection.<ref name=esaled>{{cite web|url=http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=48661|title=New approach for L-class mission candidates|publisher=European Space Agency|date=April 19, 2011|last1=Favata|first1=Fabio|access-date=May 2, 2012|archive-date=April 2, 2013|archive-url=https://web.archive.org/web/20130402143829/http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=48661|url-status=live}}</ref> These plans have been realized as the European Space Agency's [[Jupiter Icy Moon Explorer]] (JUICE), launched on April 14, 2023,<ref name="bbc-20230214">{{Cite news|date=April 14, 2023|title=European Space Agency: Blast off for Jupiter icy moons mission|language=en-GB|work=BBC News|url=https://www.bbc.com/news/science-environment-65273857|access-date=April 14, 2023|archive-date=April 14, 2023|archive-url=https://web.archive.org/web/20230414114037/https://www.bbc.com/news/science-environment-65273857|url-status=live}}</ref> followed by NASA's ''[[Europa Clipper]]'' mission, launched on October 14, 2024.<ref>{{cite web|last=Foust|first=Jeff|url=https://spacenews.com/cost-growth-prompts-changes-to-europa-clipper-instruments/|title=Cost growth prompts changes to Europa Clipper instruments|work=Space News|date=July 10, 2020|access-date=July 10, 2020|archive-date=September 29, 2021|archive-url=https://web.archive.org/web/20210929074855/https://spacenews.com/cost-growth-prompts-changes-to-europa-clipper-instruments/|url-status=live}}</ref>

Other proposed missions include the [[Chinese National Space Administration]]'s ''[[Tianwen-4]]'' mission which aims to launch an orbiter to the Jovian system and possibly [[Callisto (moon)|Callisto]] around 2035,<ref>{{cite news
 | title=Jupiter Mission by China Could Include Callisto Landing
 | first=Andrew
 | last=Jones
 | date=January 12, 2021
| publisher=The Planetary Society
 | url=https://www.planetary.org/articles/jupiter-mission-callisto-landing
 | access-date=April 27, 2020
| archive-date=April 27, 2021
| archive-url=https://web.archive.org/web/20210427053454/https://www.planetary.org/articles/jupiter-mission-callisto-landing
 | url-status=live
 }}</ref> and CNSA's ''[[Interstellar Express]]''<ref>{{cite news
 | title=China to launch a pair of spacecraft towards the edge of the solar system
 | first=Andrew
 | last=Jones
 | date=April 16, 2021
| work=Space News
 | url=https://spacenews.com/china-to-launch-a-pair-of-spacecraft-towards-the-edge-of-the-solar-system/
 | access-date=April 27, 2020
| archive-date=May 15, 2021
| archive-url=https://archive.today/20210515103459/https://spacenews.com/china-to-launch-a-pair-of-spacecraft-towards-the-edge-of-the-solar-system/
 | url-status=live
 }}</ref> and NASA's ''[[Interstellar Probe (spacecraft)|Interstellar Probe]]'',<ref>{{cite web
 | first=Lee
 | last=Billings
 | date=November 12, 2019
| website=Scientific American
 | title=Proposed Interstellar Mission Reaches for the Stars, One Generation at a Time
 | url=https://www.scientificamerican.com/article/proposed-interstellar-mission-reaches-for-the-stars-one-generation-at-a-time1/
 | access-date=April 27, 2020
| archive-date=July 25, 2021
| archive-url=https://web.archive.org/web/20210725054502/https://www.scientificamerican.com/article/proposed-interstellar-mission-reaches-for-the-stars-one-generation-at-a-time1/
 | url-status=live
 }}</ref> which would both use Jupiter's gravity to help them reach the edges of the heliosphere.

== Moons ==
{{Main|Moons of Jupiter}}
{{See also|Timeline of discovery of Solar System planets and their moons|Satellite system (astronomy)}}

Jupiter has 97 known [[natural satellite]]s,<ref name="jplsats-disc">{{cite web|title = Planetary Satellite Discovery Circumstances|url = https://ssd.jpl.nasa.gov/sats/discovery.html|work = JPL Solar System Dynamics|publisher = NASA|date = 30 April 2025|accessdate = 30 April 2025|archive-date = 27 September 2021|archive-url = https://web.archive.org/web/20210927162554/https://ssd.jpl.nasa.gov/sats/discovery.html|url-status = live}}</ref> and it is likely that this number will go up due to increasing telescopic observations.<ref>{{Cite web |last=Greenfieldboyce |first=Nell |date=February 9, 2023 |title=Here's why Jupiter's tally of moons keeps going up and up |url=https://www.npr.org/2023/02/09/1155425572/heres-why-jupiters-tally-of-moons-keeps-going-up-and-up |website=NPR |access-date=March 29, 2023 |archive-date=March 5, 2023 |archive-url=https://web.archive.org/web/20230305203115/https://www.npr.org/2023/02/09/1155425572/heres-why-jupiters-tally-of-moons-keeps-going-up-and-up |url-status=live }}</ref> Of these, only 16 are larger than 10&nbsp;km in diameter.<ref name="SheppardMoons">{{Cite web |last=Sheppard |first=Scott S. |title=Moons of Jupiter |url=https://sites.google.com/carnegiescience.edu/sheppard/moons/jupitermoons|publisher=Carnegie Institution for Science|accessdate=30 April 2025}}</ref> The four largest moons, known as the [[Galilean moons]], are Ganymede, Callisto, Io, and Europa (in order of decreasing size), and are visible from Earth with binoculars on a clear night.<ref>{{cite book|title=A Stargazing Program for Beginners|page=104|year=2015|last1=Carter|first1=Jamie|publisher=Springer International Publishing|isbn=978-3-319-22072-7}}</ref>

=== Galilean moons ===
{{Main|Galilean moons}}
The moons discovered by Galileo—Io, Europa, Ganymede, and Callisto—are among the largest in the Solar System. The orbits of Io, Europa, and Ganymede form a pattern known as a [[Laplace resonance]]; for every four orbits that Io makes around Jupiter, Europa makes exactly two orbits and Ganymede makes exactly one. This resonance causes the gravitational effects of the three large moons to distort their orbits into elliptical shapes, because each moon receives an extra tug from its neighbours at the same point in every orbit it makes. The [[tidal force]] from Jupiter, on the other hand, works to [[Tidal circularization|circularize]] their orbits.<ref>{{cite journal | last1=Musotto | first1=S. | last2=Varadi | first2=F. | last3=Moore | first3=W. B. | last4=Schubert | first4=G. |title=Numerical simulations of the orbits of the Galilean satellites |url=http://cat.inist.fr/?aModele=afficheN&cpsidt=13969974 |journal=Icarus |year=2002 |volume=159 |issue=2 |pages=500–504 |doi=10.1006/icar.2002.6939 |bibcode=2002Icar..159..500M |access-date=February 19, 2007 |archive-date=August 10, 2011 |archive-url=https://web.archive.org/web/20110810071532/http://cat.inist.fr/?aModele=afficheN&cpsidt=13969974 |url-status=dead }}</ref>

The [[Orbital eccentricity|eccentricity]] of their orbits causes regular flexing of the three moons' shapes, with Jupiter's gravity stretching them out as they approach it and allowing them to spring back to more spherical shapes as they swing away. The [[friction]] created by this tidal flexing [[Tidal acceleration#Tidal heating|generates heat]] in the interior of the moons.<ref name=Eccen304>{{cite book|page=304|title=The Cambridge Guide to the Solar System|date=March 3, 2011|last1=Lang|first1=Kenneth R.|publisher=Cambridge University Press|isbn=978-1-139-49417-5}}</ref> This is seen most dramatically in the [[Io (moon)#Volcanism|volcanic activity]] of Io (which is subject to the strongest tidal forces),<ref name="Eccen304"/> and to a lesser degree in the geological youth of [[Europa (moon)#Surface features|Europa's surface]], which indicates recent resurfacing of the moon's exterior.<ref>{{cite book|page=446|title=Encyclopedia of the Solar System|year=2006|last1=McFadden|first1=Lucy-Ann|last2=Weissmann|first2=Paul|last3=Johnson|first3=Torrence|publisher=Elsevier Science|isbn=978-0-08-047498-4}}</ref>

{| style="width:550px; margin:0 auto;" cellpadding=0 cellspacing=0
|
{| class="wikitable" style="text-align:right; margin:0 auto;"
|+ The Galilean moons compared to the Earth's [[Moon]]
|-
! rowspan=2 | Name
! rowspan=2 | [[Help:IPA/English|IPA]]
! colspan=2 | Diameter
! colspan=2 | Mass
! colspan=2 | Orbital radius
! colspan=2 | Orbital period
|-
! km
! ''D''<sub>☾</sub>
! kg
! ''M''<sub>☾</sub>
! km
! ''a''<sub>☾</sub>
! days
! ''T''<sub>☾</sub>
|-
! [[Io (moon)|Io]]
| align=left | {{small|{{IPAc-en|ˈ|aɪ|.|oʊ}}}}
| 3,643
| 1.05
| 8.9×10<sup>22</sup>
| 1.20
| 421,700
| 1.10
| 1.77
| 0.07
|-
! [[Europa (moon)|Europa]]
| align=left | {{small|{{IPAc-en|j|ʊ|ˈ|r|oʊ|p|ə}}}}
| 3,122
| 0.90
| 4.8×10<sup>22</sup>
| 0.65
| 671,034
| 1.75
| 3.55
| 0.13
|-
! [[Ganymede (moon)|Ganymede]]
| align=left | {{small|{{IPAc-en|ˈ|ɡ|æ|n|ɪ|m|iː|d}}}}
| 5,262
| 1.50
| 14.8×10<sup>22</sup>
| 2.00
| 1,070,412
| 2.80
| 7.15
| 0.26
|-
! [[Callisto (moon)|Callisto]]
| align=left | {{small|{{IPAc-en|k|ə|ˈ|l|ɪ|s|t|oʊ}}}}
| 4,821
| 1.40
| 10.8×10<sup>22</sup>
| 1.50
| 1,882,709
| 4.90
| 16.69
| 0.61
|}
|-
| [[File:The Galilean satellites (the four largest moons of Jupiter).tif|frameless|561px|center|The Galilean satellites in false colour. From left to right, in order of increasing distance from Jupiter: [[Io (moon)|Io]], [[Europa (moon)|Europa]], [[Ganymede (moon)|Ganymede]], [[Callisto (moon)|Callisto]].]]
|-
| style="font-size:0.9em; text-align:center;" | The Galilean satellites [[Io (moon)|Io]], [[Europa (moon)|Europa]], [[Ganymede (moon)|Ganymede]], and [[Callisto (moon)|Callisto]] (in order of increasing distance from Jupiter) in false colour
|}

=== Classification ===

Jupiter's moons were classified into four groups of four, based on their similar [[orbital elements]].<ref>{{cite journal|url=https://www.sciencedirect.com/science/article/abs/pii/0019103581901512|title=Derivation of the collision probability between orbiting objects: the lifetimes of jupiter's outer moons|date=October 1981|volume=48|issue=1|last1=Kessler|first1=Donald J.|journal=Icarus|pages=39–48|doi=10.1016/0019-1035(81)90151-2|bibcode=1981Icar...48...39K|s2cid=122395249 |access-date=December 30, 2020|archive-date=September 29, 2021|archive-url=https://web.archive.org/web/20210929074926/https://www.sciencedirect.com/science/article/abs/pii/0019103581901512|url-status=live|url-access=subscription}}</ref> This picture has been complicated by the discovery of numerous small outer moons since 1999. Jupiter's moons are divided into several different groups, although there are two known moons which are not part of any group ([[Themisto (moon)|Themisto]] and [[Valetudo (moon)|Valetudo]]).<ref>{{cite book|page=14|title=Moons of the Solar System|year=2013|last1=Hamilton|first1=Thomas W. M.|publisher=SPBRA|isbn=978-1-62516-175-8}}</ref>

The eight innermost [[regular moon]]s, which have nearly circular orbits near the plane of Jupiter's equator, are thought to have formed alongside Jupiter, while the remainder are [[irregular moons]] and are thought to be [[Asteroid capture|captured asteroids]] or fragments of captured asteroids. The irregular moons within each group may have a common origin, perhaps as a larger moon or captured body that broke up.<ref>{{cite book | last1=Jewitt | first1=D. C. | last2=Sheppard | first2=S. | last3=Porco | first3=C. | editor1-last=Bagenal | editor1-first=F. | editor2-last=Dowling | editor2-first=T. | editor3-last=McKinnon | editor3-first=W. | date=2004 | title=Jupiter: The Planet, Satellites and Magnetosphere | publisher=Cambridge University Press | isbn=978-0-521-81808-7 | url=http://www.ifa.hawaii.edu/~jewitt/papers/JUPITER/JSP.2003.pdf | archive-url=https://web.archive.org/web/20090326065151/http://www.ifa.hawaii.edu/~jewitt/papers/JUPITER/JSP.2003.pdf | archive-date=March 26, 2009 }}</ref><ref name="Nesvorný">{{cite journal | last1=Nesvorný | first1=D. | last2=Alvarellos | first2=J. L. A. | last3=Dones | first3=L. | last4=Levison | first4=H. F. | title=Orbital and Collisional Evolution of the Irregular Satellites | journal=The Astronomical Journal | year=2003 | volume=126 | issue=1 | pages=398–429 | bibcode=2003AJ....126..398N | doi=10.1086/375461 | s2cid=8502734 | url=http://www.boulder.swri.edu/%7Edavidn/papers/irrbig.pdf | access-date=August 25, 2019 | archive-date=August 1, 2020 | archive-url=https://web.archive.org/web/20200801203200/https://www.boulder.swri.edu/~davidn/papers/irrbig.pdf | url-status=live }}</ref>

{| class="wikitable"
! colspan="2" | Regular moons
|-
| [[Inner satellites of Jupiter|Inner group]]
| The inner group of four small moons all have diameters of less than 200&nbsp;km, orbit at radii less than 200,000&nbsp;km, and have orbital inclinations of less than half a degree.<ref name="nasa_orbit_parameters">{{Cite web |date=August 23, 2013 |title=Planetary Satellite Mean Orbital Parameters |url=http://ssd.jpl.nasa.gov/?sat_elem |access-date=February 1, 2016 |publisher=[[JPL]], [[NASA]] |archive-date=November 3, 2013 |archive-url=https://web.archive.org/web/20131103134221/http://ssd.jpl.nasa.gov/?sat_elem |url-status=live }}, and references therein.</ref> 
|-
| [[Galilean moons|Galilean&nbsp;moons]]<ref>{{cite journal | title=The Galilean Satellites | last1=Showman | first1=A. P. | last2=Malhotra | first2=R. | journal=Science | year=1999 | volume=286 | issue=5437 | pages=77–84 | doi=10.1126/science.286.5437.77 | pmid=10506564 | s2cid=9492520 | bibcode=1999Sci...296...77S }}</ref>
| These four moons, discovered by [[Galileo Galilei]] and by [[Simon Marius]] in parallel, orbit between 400,000 and 2 million&nbsp;km, and are some of the largest moons in the Solar System.
|-
! colspan="2" | Irregular moons
|-
| [[Himalia group]]
| A tightly clustered group of [[Retrograde motion|prograde-orbiting]] moons with orbits around 11–12 million&nbsp;km from Jupiter<ref>{{cite journal|first1=Scott S.|last1=Sheppard|first2=David C.|last2=Jewitt|author-link1=Scott S. Sheppard|author-link2=David C. Jewitt|title=An abundant population of small irregular satellites around Jupiter|journal=Nature|volume=423|date=May 2003|issue=6937|pages=261–263|url=http://www.ifa.hawaii.edu/~jewitt/papers/JSATS/SJ2003.pdf|archive-url=https://web.archive.org/web/20060813235622/http://www.ifa.hawaii.edu/~jewitt/papers/JSATS/SJ2003.pdf|doi=10.1038/nature01584|pmid=12748634|bibcode=2003Natur.423..261S|s2cid=4424447|archive-date=August 13, 2006}}</ref>
|-
| [[Carpo (moon)|Carpo group]]
|  A sparsely populated group of small moons with highly inclined prograde orbits around 16–17 million&nbsp;km from Jupiter<ref name="SheppardMoons"/>
|-
| [[Ananke group|Ananke&nbsp;group]]
| This group of [[Retrograde motion|retrograde-orbiting]] moons has rather indistinct borders, averaging 21.3 million&nbsp;km from Jupiter with an average inclination of 149 degrees.<ref name="Nesvorný"/>
|-
| [[Carme group]]
| A tightly clustered group of retrograde-orbiting moons that averages 23.4 million&nbsp;km from Jupiter with an average inclination of 165 degrees<ref name="Nesvorný"/>
|-
| [[Pasiphae group]]
| A dispersed and vaguely distinct retrograde group that covers all the outermost moons<ref>{{cite journal|first1=David|last1=Nesvorný|first2=Cristian|last2=Beaugé|first3=Luke|last3=Dones|last4=Levison|first4=Harold F.|title=Collisional Origin of Families of Irregular Satellites|journal=The Astronomical Journal|volume=127|date=July 2003|issue=3|pages=1768–1783|doi=10.1086/382099 | bibcode=2004AJ....127.1768N |s2cid=27293848 | url=http://www.boulder.swri.edu/~davidn/papers/irrbig.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.boulder.swri.edu/~davidn/papers/irrbig.pdf |archive-date=October 9, 2022 |url-status=live}}</ref>
|}

== Interaction with the Solar System ==
As the most massive of the eight planets, the gravitational influence of Jupiter has helped shape the Solar System. With the exception of [[Mercury (planet)|Mercury]], the orbits of the system's planets lie closer to Jupiter's [[orbital plane (astronomy)|orbital plane]] than the Sun's [[celestial equator|equatorial plane]]. The [[Kirkwood gap]]s in the [[asteroid belt]] are mostly caused by Jupiter,<ref>{{cite conference | title=Kirkwood Gaps and Resonant Groups | last=Ferraz-Mello | first=S. | conference=Asteroids, Comets, Meteors 1993: Proceedings of the 160th Symposium of the International Astronomical Union, held in Belgirate, Italy, June 14–18, 1993, International Astronomical Union. Symposium no. 160 | editor1-first=Andrea | editor1-last=Milani | editor2-first=Michel | editor2-last=Di Martino | editor3-first=A. | editor3-last=Cellino | publication-place=Dordrecht | publisher=Kluwer Academic Publishers | page=175 | date=1994 | bibcode=1994IAUS..160..175F }}</ref> and the planet may have been responsible for the [[Late Heavy Bombardment]] in the inner Solar System's history.<ref>{{cite journal | last=Kerr | first=Richard A. | title=Did Jupiter and Saturn Team Up to Pummel the Inner Solar System? | journal=Science | year=2004 | volume=306 | issue=5702 | page=1676 | doi=10.1126/science.306.5702.1676a | pmid=15576586| s2cid=129180312 }}</ref>

In addition to its moons, Jupiter's gravitational field controls numerous [[asteroid]]s that have settled around the [[Lagrangian point]]s that precede and follow the planet in its orbit around the Sun. These are known as the [[Trojan asteroid]]s, and are divided into [[List of Trojan asteroids (Greek camp)|Greek]] and [[List of Trojan asteroids (Trojan camp)|Trojan]] "camps" to honour the ''[[Iliad]]''. The first of these, [[588 Achilles]], was discovered by [[Max Wolf]] in 1906; since then more than two thousand have been discovered.<ref>{{cite web |url=http://www.minorplanetcenter.org/iau/lists/JupiterTrojans.html |title=List Of Jupiter Trojans |access-date=October 24, 2010 |work=IAU Minor Planet Center |archive-date=July 25, 2011 |archive-url=https://web.archive.org/web/20110725080850/http://www.minorplanetcenter.org/iau/lists/JupiterTrojans.html |url-status=live }}</ref> The largest is [[624 Hektor]].<ref>{{cite journal | bibcode=2000DPS....32.1901C | title=Trojan Asteroid 624 Hektor: Constraints on Surface Composition | last1=Cruikshank | first1=D. P. | last2=Dalle Ore | first2=C. M. |author2-link=Cristina Dalle Ore| last3=Geballe | first3=T. R. | last4=Roush | first4=T. L. | last5=Owen | first5=T. C. | last6=Cash | first6=Michele | last7=de Bergh | first7=C. | last8=Hartmann | first8=W. K. | date=October 2000 | journal=Bulletin of the American Astronomical Society | volume=32 | page=1027 }}</ref>

The Jupiter family is defined as comets that have a [[semi-major axis]] smaller than Jupiter's; most [[List of periodic comets|short-period comets]] belong to this group. Members of the Jupiter family are thought to form in the [[Kuiper belt]] outside the orbit of Neptune. During close encounters with Jupiter, they are [[Perturbation (astronomy)|perturbed]] into orbits with a smaller period, which then becomes circularized by regular gravitational interactions with the Sun and Jupiter.<ref>{{cite journal | last1=Quinn | first1=T. | last2=Tremaine | first2=S. | last3=Duncan | first3=M. | title=Planetary perturbations and the origins of short-period comets | journal=Astrophysical Journal, Part 1 | year=1990 | volume=355 | pages=667–679 | bibcode=1990ApJ...355..667Q | doi=10.1086/168800 | doi-access=free }}</ref>

=== Impacts ===
{{Main|Impact events on Jupiter}}
[[File:Jupiter showing SL9 impact sites.jpg|thumb|Brown spots mark [[Comet Shoemaker–Levy 9]]'s impact sites on Jupiter]]
Jupiter has been called the Solar System's [[Comet Shoemaker–Levy 9#Jupiter's role in protection of the inner Solar System|vacuum cleaner]]<ref>{{cite news | title=Caught in the act: Fireballs light up Jupiter | work=ScienceDaily | date=September 10, 2010 | url=https://www.sciencedaily.com/releases/2010/09/100909212309.htm | access-date=April 26, 2022 | archive-date=April 27, 2022 | archive-url=https://web.archive.org/web/20220427013242/https://www.sciencedaily.com/releases/2010/09/100909212309.htm | url-status=live }}</ref> because of its immense [[gravity well]] and location near the inner Solar System. There are more [[List of Jupiter events|impacts on Jupiter]], such as comets, than on any other planet in the Solar System.<ref>{{cite journal | last1=Nakamura | first1=T. | last2=Kurahashi | first2=H. | title=Collisional Probability of Periodic Comets with the Terrestrial Planets: An Invalid Case of Analytic Formulation | journal=Astronomical Journal | year=1998 | volume=115 | issue=2 | pages=848–854 | doi=10.1086/300206 | bibcode=1998AJ....115..848N | doi-access=free }}</ref> For example, Jupiter experiences about 200 times more [[asteroid]] and [[comet]] impacts than Earth.<ref name="HTUW"/> Scientists used to believe that Jupiter partially shielded the inner system from cometary bombardment.<ref name="HTUW"/> However, computer simulations in 2008 suggest that Jupiter does not cause a net decrease in the number of comets that pass through the inner Solar System, as its gravity perturbs their orbits inward roughly as often as it [[Accretion (astrophysics)|accretes]] or ejects them.<ref>{{cite journal | last1=Horner | first1=J. | last2=Jones | first2=B. W. | year=2008 | title=Jupiter – friend or foe? I: the asteroids. | journal=International Journal of Astrobiology | volume=7 | issue=3–4 | pages=251–261 | doi=10.1017/S1473550408004187 | arxiv=0806.2795 | bibcode=2008IJAsB...7..251H| s2cid=8870726 }}</ref> This topic remains controversial among scientists, as some think it draws comets towards Earth from the [[Kuiper belt]], while others believe that Jupiter protects Earth from the [[Oort cloud]].<ref>{{cite news |first=Dennis |last=Overbye |author-link=Dennis Overbye |date=July 25, 2009 |title=Jupiter: Our Cosmic Protector? |work=[[The New York Times]] |access-date=July 27, 2009 |url=https://www.nytimes.com/2009/07/26/weekinreview/26overbye.html |archive-date=April 24, 2012 |archive-url=https://web.archive.org/web/20120424054444/http://www.nytimes.com/2009/07/26/weekinreview/26overbye.html |url-status=live }}</ref>

In July 1994, the [[Comet Shoemaker–Levy 9]] comet collided with Jupiter.<ref>{{Cite web|title=In Depth {{!}} P/Shoemaker-Levy 9|url=https://solarsystem.nasa.gov/asteroids-comets-and-meteors/comets/p-shoemaker-levy-9/in-depth|access-date=December 3, 2021|website=NASA Solar System Exploration|date=December 9, 2017 |archive-date=February 2, 2022|archive-url=https://web.archive.org/web/20220202124627/https://solarsystem.nasa.gov/asteroids-comets-and-meteors/comets/p-shoemaker-levy-9/in-depth/|url-status=live}}</ref><ref>{{Cite web|last=Howell|first=Elizabeth|date=January 24, 2018|title=Shoemaker-Levy 9: Comet's Impact Left Its Mark on Jupiter|url=https://www.space.com/19855-shoemaker-levy-9.html|access-date=December 3, 2021|website=Space.com|language=en|archive-date=December 6, 2021|archive-url=https://web.archive.org/web/20211206063559/https://www.space.com/19855-shoemaker-levy-9.html|url-status=live}}</ref> The impacts were closely observed by observatories around the world, including the [[Hubble Space Telescope]] and ''Galileo'' spacecraft.<ref>{{Cite web|last=information@eso.org|title=The Big Comet Crash of 1994 – Intensive Observational Campaign at ESO|url=https://www.eso.org/public/news/eso9402/|access-date=December 3, 2021|website=eso.org|language=en|archive-date=December 3, 2021|archive-url=https://web.archive.org/web/20211203094812/https://www.eso.org/public/news/eso9402/|url-status=live}}</ref><ref>{{Cite web|title=Top 20 Comet Shoemaker-Levy Images|url=https://www2.jpl.nasa.gov/sl9/top20.html|access-date=December 3, 2021|website=www2.jpl.nasa.gov|archive-date=November 27, 2021|archive-url=https://web.archive.org/web/20211127142402/https://www2.jpl.nasa.gov/sl9/top20.html|url-status=live}}</ref><ref>{{Cite web | title=Hubble Observations Shed New Light on Jupiter Collision | first1=Donald | last1=Savage | first2=Jim | last2=Elliott | first3=Ray | last3=Villard | url=https://nssdc.gsfc.nasa.gov/planetary/hst_obs.html | access-date=December 3, 2021 | date=December 30, 2004 | website=nssdc.gsfc.nasa.gov | archive-date=November 12, 2021 | archive-url=https://web.archive.org/web/20211112014938/https://nssdc.gsfc.nasa.gov/planetary/hst_obs.html | url-status=live }}</ref> The event was widely covered by the media.<ref>{{Cite web|title=NASA TV Coverage on Comet Shoemaker-Levy|url=https://www2.jpl.nasa.gov/sl9/tv_nasa.html|access-date=December 3, 2021|website=www2.jpl.nasa.gov|archive-date=September 8, 2021|archive-url=https://web.archive.org/web/20210908101213/https://www2.jpl.nasa.gov/sl9/tv_nasa.html|url-status=live}}</ref>

Surveys of early astronomical records and drawings produced eight examples of potential impact observations between 1664 and 1839. However, a 1997 review determined that these observations had little or no possibility of being the results of impacts. Further investigation by this team revealed a dark surface feature discovered by astronomer [[Giovanni Domenico Cassini|Giovanni Cassini]] in 1690 may have been an impact scar.<ref>{{Cite journal | last1=Tabe | first1=Isshi | last2=Watanabe | first2=Jun-ichi | last3=Jimbo | first3=Michiwo | date=February 1997 |title=Discovery of a Possible Impact SPOT on Jupiter Recorded in 1690 | journal=Publications of the Astronomical Society of Japan | volume=49 | pages=L1–L5 | bibcode=1997PASJ...49L...1T | doi=10.1093/pasj/49.1.l1 | doi-access=free }}</ref>

== In culture ==
{{See also|Jupiter in fiction|Planets in astrology#Jupiter}}
[[File:Jupiter-bonatti.png|thumb|Jupiter, woodcut from a 1550 edition of [[Guido Bonatti]]'s ''Liber Astronomiae''|left]]
The existence of the planet Jupiter has been known since ancient times. It is visible to the naked eye in the night sky and can be seen in the daytime when the Sun is low.<ref>{{cite news |date=June 16, 2005 |title=Stargazers prepare for daylight view of Jupiter |publisher=[[ABC News (Australia)|ABC News]] |url=http://www.abc.net.au/news/newsitems/200506/s1393223.htm |archive-url=https://web.archive.org/web/20110512163240/http://www.abc.net.au/news/newsitems/200506/s1393223.htm |archive-date=May 12, 2011 |access-date=February 28, 2008}}</ref> To the [[Babylon]]ians, this planet represented their god [[Marduk]],<ref name="Rogers1998"/> chief of their pantheon from the [[Hammurabi]] period.<ref>{{cite book | last=Waerden | first=B. L. | title=Science Awakening II | chapter=Old-Babylonian Astronomy | date=1974 | pages=46–59 | publisher=Springer | doi=10.1007/978-94-017-2952-9_3 | isbn=978-90-481-8247-3 | publication-place=Dordrecht | chapter-url=https://link.springer.com/content/pdf/10.1007/978-94-017-2952-9_3.pdf |archive-url=https://web.archive.org/web/20220321164438/https://link.springer.com/content/pdf/10.1007/978-94-017-2952-9_3.pdf |archive-date=March 21, 2022 |url-status=live | access-date=March 21, 2022 }}</ref> They used Jupiter's roughly 12-year orbit along the [[ecliptic]] to define the [[constellation]]s of their [[zodiac]].<ref name=Rogers1998>{{cite journal | last=Rogers | first=J. H. | title=Origins of the ancient constellations: I. The Mesopotamian traditions | journal=Journal of the British Astronomical Association | year=1998 | volume=108 | pages=9–28 | bibcode=1998JBAA..108....9R }}</ref>

The [[Greek mythology|mythical Greek]] name for this planet is ''[[Zeus]]'' (Ζεύς), also referred to as ''Dias'' (Δίας), the planetary name of which is retained in modern [[Greek language|Greek]].<ref>{{cite web |url=http://www.greek-names.info/greek-names-of-the-planets/ |title=Greek Names of the Planets |access-date=July 14, 2012 |quote=In Greek the name of the planet Jupiter is Dias, the Greek name of god Zeus. |date=April 25, 2010 |archive-date=May 9, 2010 |archive-url=https://web.archive.org/web/20100509164917/http://www.greek-names.info/greek-names-of-the-planets/ |url-status=live }}  See also [[:el:Δίας (πλανήτης)|the Greek article about the planet]].</ref> The ancient Greeks knew the planet as [[Phaethon]] ({{langx|grc|Φαέθων|label=none}}), meaning "shining one" or "blazing star".<ref>{{Cite book |year=1888 |title=Cicero's Tusculan Disputations; also, Treatises on The Nature of the Gods, and on The Commonwealth |last=Cicero |first=Marcus Tullius |language=en |translator-last=Yonge |translator-first=Charles Duke |url=https://archive.org/details/cicerostusculand00ciceuoft |publisher=Harper & Brothers |location=New York, NY |page=[https://archive.org/details/cicerostusculand00ciceuoft/page/274 274] |via=[[Internet Archive]]}}</ref><ref>{{cite book |last=Cicero |first=Marcus Tullus |author-link=Cicero |editor-last=Warmington |editor-first=E. H. |translator-last=Rackham |translator-first=H. |year=1967 |orig-year=1933 |title=De Natura Deorum |trans-title=On The Nature of the Gods |url=https://archive.org/details/denaturadeorumac00ciceuoft |publisher=Cambridge University Press |location=Cambridge, MA |series=Cicero |volume=19 |page=[https://archive.org/details/denaturadeorumac00ciceuoft/page/175 175] |via=[[Internet Archive]]}}</ref> The Greek myths of Zeus from the [[Homer]]ic period showed particular similarities to certain [[Near East|Near-Eastern]] gods, including the Semitic [[El (deity)|El]] and [[Baal]], the Sumerian [[Enlil]], and the Babylonian god Marduk.<ref>{{cite journal | last=Zolotnikova | first=O. | date=2019 | title=Mythologies in contact: Syro-Phoenician traits in Homeric Zeus | journal=The Scientific Heritage | volume=41 | issue=5 | pages=16–24 | url=https://www.academia.edu/41482655 | access-date=April 26, 2022 | archive-date=August 9, 2022 | archive-url=https://web.archive.org/web/20220809222951/https://www.academia.edu/41482655 | url-status=live }}</ref> The association between the planet and the Greek deity Zeus was drawn from Near Eastern influences and was fully established by the fourth century BC, as documented in the ''[[Epinomis]]'' of [[Plato]] and his contemporaries.<ref>{{cite journal | last=Tarnas | first=R. | date=2009 | title=The planets | journal=Archai: The Journal of Archetypal Cosmology | volume=1 | issue=1 | pages=36–49 | citeseerx=10.1.1.456.5030 }}</ref>

The god [[Jupiter (god)|Jupiter]] is the Roman counterpart of Zeus, and he is the principal [[List of Roman deities|god]] of [[Roman mythology]]. The Romans originally called Jupiter the "star of Jupiter" (''Iuppiter Stella''), as they believed it to be sacred to its namesake god. This name comes from the [[Proto-Indo-European language|Proto-Indo-European]] [[vocative]] compound *''Dyēu-pəter'' (nominative: *''[[Dyeus|Dyēus]]-pətēr'', meaning "Father Sky-God", or "Father Day-God").<ref name="etymologyonline">{{cite web |last=Harper |first=Douglas |date=November 2001 |url=http://www.etymonline.com/index.php?term=Jupiter |title=Jupiter |work=Online Etymology Dictionary |access-date=February 23, 2007 |archive-date=September 28, 2008 |archive-url=https://web.archive.org/web/20080928101056/http://www.etymonline.com/index.php?term=Jupiter |url-status=live }}</ref> As the supreme god of the Roman pantheon, Jupiter was the god of thunder, lightning, and storms, and was called the god of light and sky.<ref>{{cite journal|title=The Common Attributes Between The Baltic Thunder God Perkunas And His Antique Equivalents Jupiter And Zeus|author=Vytautas Tumėnas|journal=Mediterranean Archaeology and Archaeometry|volume=16|number=4|year=2016|pages=359–367|url=http://tautosmenta.lt/wp-content/uploads/2013/12/Tumenas_Vytautas/Tumenas_MAA_16_4_2016.pdf|access-date=July 19, 2023|archive-date=July 19, 2023|archive-url=https://web.archive.org/web/20230719002118/http://tautosmenta.lt/wp-content/uploads/2013/12/Tumenas_Vytautas/Tumenas_MAA_16_4_2016.pdf|url-status=live}}</ref>

In [[Jyotisha|Vedic astrology]], Hindu astrologers named the planet after [[Brihaspati]], the religious teacher of the gods, and called it "[[Guru]]", which means the "Teacher".<ref>{{cite web |url=http://www.webonautics.com/mythology/guru_jupiter.html |title=Guru |publisher=Indian Divinity.com |access-date=February 14, 2007 |archive-date=September 16, 2008 |archive-url=https://web.archive.org/web/20080916192305/http://www.webonautics.com/mythology/guru_jupiter.html |url-status=live }}</ref><ref>{{cite journal | title=Astrolatry in the Brahmaputra Valley: Reflecting upon the Navagraha Sculptural Depiction | last1=Sanathana | first1=Y. S. | last2=Manjil | first2=Hazarika | journal=Heritage: Journal of Multidisciplinary Studies in Archaeology | date=November 27, 2020 | volume=8 | issue=2 | pages=157–174 | url=https://www.academia.edu/download/83171079/Astrolatry_in_the_Brahmaputra_Valley_Reflecting_upon_the_Navagraha_Sculptural_Depiction.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://www.academia.edu/download/83171079/Astrolatry_in_the_Brahmaputra_Valley_Reflecting_upon_the_Navagraha_Sculptural_Depiction.pdf |archive-date=October 9, 2022 |url-status=live | access-date=July 4, 2022 }}{{dead link|date=July 2022|bot=medic}}{{cbignore|bot=medic}}</ref> In [[Turkic mythology|Central Asian Turkic myths]], Jupiter is called ''Erendiz'' or ''Erentüz'', from ''eren'' (of uncertain meaning) and ''yultuz'' ("star"). The Turks calculated the period of the orbit of Jupiter as 11 years and 300 days. They believed that some social and natural events connected to Erentüz's movements in the sky.<ref>{{cite news |url=http://www.ntvmsnbc.com/id/25085903/ |title=Türk Astrolojisi-2 |publisher=[[NTV (Turkey)|NTV]] |language=tr |access-date=April 23, 2010 |archive-url=https://archive.today/20130104145343/http://www.ntvmsnbc.com/id/25085903/ |archive-date=January 4, 2013 |url-status=dead }}</ref> The Chinese, Vietnamese, Koreans, and Japanese called it the "wood star" ({{lang-zh|c=木星|p=mùxīng}}), based on the Chinese [[Five elements (Chinese philosophy)|Five Elements]].<ref>{{cite book |first=Jan Jakob Maria |last=De Groot |year=1912 |title=Religion in China: universism. a key to the study of Taoism and Confucianism |series=American lectures on the history of religions |volume=10 |page=300 |publisher=G.P. Putnam's Sons |url=https://books.google.com/books?id=ZAaP7dyjCrAC&pg=PA300 |access-date=January 8, 2010 |archive-date=February 26, 2024 |archive-url=https://web.archive.org/web/20240226150305/https://books.google.com/books?id=ZAaP7dyjCrAC&pg=PA300#v=onepage&q&f=false |url-status=live }}</ref><ref>{{cite book |first=Thomas |last=Crump |year=1992 |title=The Japanese numbers game: the use and understanding of numbers in modern Japan |url=https://archive.org/details/japanesenumbersg00crum |url-access=limited |series=Nissan Institute/Routledge Japanese studies series |pages=[https://archive.org/details/japanesenumbersg00crum/page/n53 39]–40 |publisher=Routledge |isbn=978-0-415-05609-0}}</ref><ref>{{cite book |first=Homer Bezaleel |last=Hulbert |year=1909 |title=The passing of Korea |page=[https://archive.org/details/passingkorea01hulbgoog/page/n538 426] |publisher=Doubleday, Page & Company |url=https://archive.org/details/passingkorea01hulbgoog |access-date=January 8, 2010}}</ref> In China, it became known as the "Year-star" (Sui-sing), as Chinese astronomers noted that it jumped one [[Chinese zodiac|zodiac]] constellation each year (with corrections). In some ancient Chinese writings, the years were, in principle, named in correlation with the Jovian zodiac signs.<ref name=Homer/>

== See also ==
{{div col|colwidth=20em}}
* {{annotated link|Outline of Jupiter}}
* {{annotated link|Eccentric Jupiter}}
* {{annotated link|Hot Jupiter}}
* {{annotated link|Super-Jupiter}}
* {{annotated link|Jovian–Plutonian gravitational effect}}
* {{annotated link|List of gravitationally rounded objects of the Solar System}}
{{div col end}}

== Notes ==
{{reflist|group=lower-alpha}}

== References ==
{{reflist| refs =
<ref name="fact">{{cite web |url=https://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html |title=Jupiter Fact Sheet |publisher=[[NASA]] |last=Williams |first=David R. |access-date=October 13, 2017 |date=December 23, 2021 |archive-date=December 29, 2019 |archive-url=https://web.archive.org/web/20191229035429/https://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html |url-status=live }}</ref>
<ref name=Souami_Souchay_2012>{{cite journal
 | title=The solar system's invariable plane
 | last1=Souami | first1=D. | last2=Souchay | first2=J.
 | journal=Astronomy & Astrophysics
 | volume=543 | id=A133 | pages=11 | date=July 2012
 | doi=10.1051/0004-6361/201219011 | bibcode=2012A&A...543A.133S | doi-access=free }}</ref>
<ref name=VSOP87>{{cite journal |title=Numerical expressions for precession formulae and mean elements for the Moon and planets |journal=Astronomy and Astrophysics |volume=282 |issue=2 |pages=663–683 |date=February 1994 |last1=Simon |first1=J. L. |last2=Bretagnon |first2=P. |last3=Chapront |first3=J. |last4=Chapront-Touzé |first4=M. |last5=Francou |first5=G. |last6=Laskar |first6=J. |bibcode=1994A&A...282..663S}}</ref>
<ref name="Mallama_and_Hilton">{{cite journal | last1=Mallama | first1=A. | last2=Hilton | first2=J. L. |title=Computing Apparent Planetary Magnitudes for The Astronomical Almanac |journal=Astronomy and Computing |volume=25 | pages=10–24 |year=2018 |doi=10.1016/j.ascom.2018.08.002 |bibcode=2018A&C....25...10M|arxiv=1808.01973 |s2cid=69912809 }}</ref>
<ref name="Li_et_al">{{cite journal
 | title=Less absorbed solar energy and more internal heat for Jupiter
 | last1=Li | first1=Liming | last2=Jiang | first2=X.
 | last3=West | first3=R. A. | last4=Gierasch | first4=P. J.
 | last5=Perez-Hoyos | first5=S. | last6=Sanchez-Lavega | first6=A.
 | last7=Fletcher | first7=L. N. | last8=Fortney | first8=J. J.
 | last9=Knowles | first9=B. | last10=Porco | first10=C. C.
 | last11=Baines | first11=K. H. | last12=Fry | first12=P. M.
 | last13=Mallama | first13=A. | last14=Achterberg | first14=R. K.
 | last15=Simon | first15=A. A. | last16=Nixon | first16=C. A.
 | last17=Orton | first17=G. S. | last18=Dyudina | first18=U. A.
 | last19=Ewald | first19=S. P. | last20=Schmude | first20=R. W.
 | journal=Nature Communications
 | volume=9 | issue=1 | page=3709 | year=2018
 | doi=10.1038/s41467-018-06107-2 | pmid=30213944
 | pmc=6137063 | bibcode=2018NatCo...9.3709L }}</ref>
<ref name="Mallama_et_al">{{cite journal |title=Comprehensive wide-band magnitudes and albedos for the planets, with applications to exo-planets and Planet Nine |journal=Icarus |first1=Anthony |last1=Mallama |first2=Bruce |last2=Krobusek |first3=Hristo |last3=Pavlov |volume=282 |pages=19–33 |year=2017 |doi=10.1016/j.icarus.2016.09.023 |bibcode=2017Icar..282...19M |arxiv=1609.05048 |s2cid=119307693 }}</ref>

<ref name="Atreya2003">{{cite journal |title=Composition and origin of the atmosphere of Jupiter—an update, and implications for the extrasolar giant planets |journal=Planetary and Space Science |last1=Atreya |first1=Sushil K. |last2=Mahaffy |first2=P. R. |last3=Niemann |first3=H. B. |last4=Wong |first4=M. H. |last5=Owen |first5=T. C. |volume=51 |issue=2 |pages=105–112 |date=February 2003 |doi=10.1016/S0032-0633(02)00144-7 |bibcode=2003P&SS...51..105A }}</ref>
}}

== Further reading ==
{{Library resources box|by=no|onlinebooksby=no|viaf=73918294}}
*{{cite book|title=Jupiter: The Planet, Satellites and Magnetosphere|last1=Bagenal|first1=Fran|author-link1=Fran Bagenal|last2=Dowling|first2=Timothy E.|last3=McKinnon|first3=William B.|year=2006|isbn=978-0-52-103545-3|url=https://books.google.com/books?id=aMERHqj9ivcC|publisher=[[Cambridge University Press]]|via=[[Google Books]]}}
* {{cite book |first=Hans |last=Lohninger |display-authors=etal |date=November 2, 2005 |chapter-url=http://www.vias.org/spacetrip/jupiter_1.html |chapter=Jupiter, As Seen By Voyager 1 |url=http://www.vias.org/spacetrip/index.html |title=A Trip into Space |publisher=Virtual Institute of Applied Science}}

== External links ==
{{Sister project links}}
* [https://science.nasa.gov/jupiter/ Jupiter overview] by NASA's [[Science Mission Directorate]]
* [http://orbitsimulator.com/gravity/articles/joviansystem.html Simulation of the 62 moons of Jupiter] from Tony Dunn's Gravity Simulator website.
* [https://web.archive.org/web/20150904035945/http://digitalcollections.ucsc.edu/cdm/search/collection/p265101coll10/searchterm/Jupiter%20(planet)/order/title Photographs of Jupiter circa 1920s] from the Lick Observatory Records Digital Archive, at the [[University of California, Santa Cruz]] Library's Digital Collections.
* [https://web.archive.org/web/20200611222440/https://gravitysimulator.org/solar-system/the-jovian-system/ Interactive 3D gravity simulation of the Jovian system]. 
* {{YouTube|Us6EXc5Hyng|Video}} of the [[2010 Jupiter impact event]] by an amateur astronomer.
* {{YouTube|CC7OJ7gFLvE|Animation|link=no}} of the [[Juno (spacecraft)|Juno]] spacecraft's flyby of [[Ganymede (moon)|Ganymede]] and Jupiter by [[NASA]].

{{Jupiter|state=expanded}}
{{Moons of Jupiter}}
{{Jupiter spacecraft}}
{{Solar System}}
{{Authority control}}
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