View source for 23 Librae b

{{Short description|Extrasolar planet in the constellation Libra}}
{{Infobox planet
| name                     = 23 Librae b
| symbol                   = 
| image                    = Planet 23 Librae b.png
|image_size                = 
| image_alt                = 
| caption                  = 23 Librae b (min mass ~1.59 MJ) as seen with Celestia
| background               = 
| bgcolour                 = 
| label_width              = 
<!-- DISCOVERY           -->
| discovery_ref = <ref name="Keck"/><ref name="Vogt2000"/>
| discoverer = [[California and Carnegie Planet Search|California and<br>Carnegie Planet Search]]
| discovery_site = [[W. M. Keck Observatory]]
| discovered = November 1, 1999
| discovery_method = [[Doppler spectroscopy]]
<!-- DESIGNATIONS        -->
| exosolar planets         = 
| minorplanet              = 
| extrasolarplanet         =  
| mpc_name                 =
| pronounced               =  
| named_after              = 
| alt_names                = 
| mp_category              = 
| adjectives               = 
<!-- ORBITAL             --> 
| orbit_ref                = 
| orbit_diagram            = 
| epoch                    = 
| uncertainty              = 
| observation_arc          = 
| earliest_precovery_date  = 
| apsis                    = astron
| aphelion                 = 
| perihelion               = 
| semimajor                = {{convert|0.81 ± 0.02|AU|km|abbr=on}}
| mean_orbit_radius        = 
| eccentricity             = 0.233 ± 0.002
| period                   = 258.19 ± 0.07 [[day|d]]<br>0.7069 [[year|y]]
| synodic_period           = 
| avg_speed                = 
| mean_anomaly             = 
| mean_motion              = 
| inclination              = 
| angular_dist             = 
| asc_node                 = 
| long_periastron          = 
| time_periastron          = 2,450,331.7 ± 2.2
| arg_peri                 = 358.3 ± 3.7
| semi-amplitude           = 49.52 ± 0.57
| satellite_of             = 
| satellites               = 
| star                     = [[23 Librae]]
| allsatellites            = 
| tisserand                = 
<!-- PHYS CHARS          --> 
| physical_ref             =
| dimensions               = 
| mean_diameter            = 
| mean_radius              = 
| equatorial_radius        = 
| polar_radius             = 
| flattening               = 
| circumference            = 
| surface_area             = 
| volume                   = 
| mass                     = 
| density                  = 
| surface_grav             = 
| moment_of_inertia_factor = 
| escape_velocity          = 
| rotation                 = 
| sidereal_day             = 
| rot_velocity             = 
| axial_tilt               = 
| right_asc_north_pole     = 
| declination              = 
| pole_ecliptic_lat        = 
| pole_ecliptic_lon        = 
| albedo                   = 
| single_temperature       = 
| spectral_type            = 
| magnitude                = 
| abs_magnitude            = 
| angular_size             = 
| family                   =
<!-- ATMOSPHERE          --> 
| atmosphere_ref           =  
| atmosphere               = 
| scale_height             = 
| surface_pressure         = 
| atmosphere_composition   = 
<!-- NOTES               --> 
| note                     =
}}
'''23 Librae b''' (23 Lib b), also known as HD 134987 b, is an extrasolar [[Jovian planet]] discovered in November 1999 orbiting the star [[23 Librae]]. It orbits in its star's [[habitable zone]].<ref name="Keck"/><ref name="Vogt2000"/><ref name="Butler2006"/>

As of 1999, the planet was known to have at least 1.5 times [[Jupiter]]'s [[mass]]. The planet orbits 23 Librae at an average distance of 0.82 [[Astronomical unit|AU]], which is between that of [[Venus]] and the [[Earth]] in the [[Solar System]].<ref name="Jones2010"/>

== See also ==

* [[List of exoplanets discovered before 2000]]

==References==
{{Reflist|refs=

<ref name="Butler2006">{{cite journal | title=Catalog of Nearby Exoplanets | last1=Butler | first1=R. P. | last2=Wright | first2=J. T. | last3=Marcy | first3=G. W. | last4=Fischer | first4=D. A. | last5=Vogt | first5=S. S. | last6=Tinney | first6=C. G. | last7=Jones | first7=H. R. A. | last8=Carter | first8=B. D. | last9=Johnson | first9=J. A. | last10=McCarthy | first10=C. | last11=Penny | first11=A. J. | display-authors=1 | journal=The Astrophysical Journal | volume=646 | issue=1 | pages=505–522 | year=2006 | arxiv=astro-ph/0607493 | bibcode=2006ApJ...646..505B | bibcode-access=free | doi=10.1086/504701 | doi-access=free }}</ref>

<ref name="Jones2010">{{cite journal | title=A long-period planet orbiting a nearby Sun-like star | last1=Jones | first1=Hugh R. A. | last2=Butler | first2=R. Paul | last3=Tinney | first3=C. G. | last4=O'Toole | first4=Simon | last5=Wittenmyer | first5=Rob | last6=Henry | first6=Gregory W. | last7=Meschiari | first7=Stefano | last8=Vogt | first8=Steve | last9=Rivera | first9=Eugenio | last10=Laughlin | first10=Greg | last11=Carter | first11=Brad D. | last12=Bailey | first12=Jeremy | last13=Jenkins | first13=James S. | display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society | volume=403 | issue=4 | pages=1703–1713 | year=2010 | arxiv=0912.2716 | bibcode=2010MNRAS.403.1703J | bibcode-access=free | doi=10.1111/j.1365-2966.2009.16232.x | doi-access=free }}</ref>

<ref name="Keck">{{cite press release | title=Astronomers discover six new planets orbiting nearby stars | date=November 1, 1999 | publisher=W. M. Keck Observatory | location=Kamuela, Hawaii | url=http://www.keckobservatory.org/astronomers_discover_six_new_planets_orbiting_nearby_stars/ | access-date=December 19, 2017 }}</ref>

<ref name="Vogt2000">{{cite journal | title=Six New Planets from the Keck Precision Velocity Survey | last1=Vogt | first1=Steven S. | last2=Marcy | first2=Geoffrey W. | last3=Butler | first3=R. Paul | last4=Apps | first4=Kevin | display-authors=1 | journal=The Astrophysical Journal | volume=536 | issue=2 | pages=902–914 | year=2000 | arxiv=astro-ph/9911506 | bibcode=2000ApJ...536..902V | bibcode-access=free | doi=10.1086/308981 | doi-access=free }}</ref>

}}

{{Sky|15|13|28|-|25|18|33|83.7}}
{{23 Librae}}

{{DEFAULTSORT:23 Librae b}}
[[Category:Libra (constellation)]]
[[Category:Exoplanets detected by radial velocity]]
[[Category:Exoplanets discovered in 1999]]
[[Category:Giant planets in the habitable zone]]

{{extrasolar-planet-stub}}