View source for Utopia Planitia

{{Short description|Impact basin on Mars}}
{{Infobox feature on celestial object
|name        = Utopia Planitia
|image       =  USGS-PlanetMars-TopographicalMap.png
|caption     = Map of the lower and mid-latitudes of Mars, with Utopia visible in dark blue in the top right
|location    = Northeast of [[Isidis Planitia]], northwest of [[Classical albedo features on Mars#A|Aetheria]]
|coordinates = {{coord|46.7|N|117.5|E|globe:mars_type:landmark|display=inline,title}}
|diameter    = {{cvt|3,300|km}}.<ref name="McGill1989"/>
|type        = Impact basin
}}
[[File:Ice on Mars Utopia Planitia (PIA00571).jpg|thumb|Frosted terrain on Utopia Planitia, taken by the [[Viking 2]] lander in 1979]]
'''Utopia Planitia''' ([[Proto-Greek language|Greek]] and [[Latin]]: "[[Utopia]] Land Plain") is a large [[plain]]<ref name = "USGS_Utopia_Planitia" /> within Utopia, the largest recognized [[impact basin]] on [[Mars]]{{efn| Officially, Utopia is an albedo feature.<ref name="USGS_Utopia">{{cite web|title=Utopia|work=Gazetteer of Planetary Nomenclature|publisher=[[USGS Astrogeology Science Center]]|url=https://planetarynames.wr.usgs.gov/Feature/6259}}</ref>}} and in the Solar System with an estimated diameter of {{cvt|3,300|km}}.<ref name="McGill1989">{{Cite journal | doi = 10.1029/JB094iB03p02753| title = Buried topography of Utopia, Mars: Persistence of a giant impact depression| journal = Journal of Geophysical Research| volume = 94| pages = 2753–2759| date = 1989-03-10| last1 = McGill | first1 = G. E. |bibcode = 1989JGR....94.2753M }}</ref> It is the Martian region where the ''[[Viking 2]]'' lander touched down and began exploring on September 3, 1976, and the [[Zhurong (rover)|''Zhurong'' rover]] touched down on May 14, 2021, as a part of the [[Tianwen-1]] mission.<ref>{{cite web|title=China succeeds on country's first Mars landing attempt with Tianwen-1|url=https://www.nasaspaceflight.com/2021/05/china-first-mars-landing-attempt-tianwen-1/|website=nasaspaceglight.com|date=15 May 2021 |access-date=May 15, 2021}}</ref><ref>{{Cite web|url=https://www.space.com/china-mars-mission-tianwen-1-details.html|title=China's first Mars rover Tianwen-1 launches this week. Here's what it will do.|website=Space.com|date=21 July 2020 }}</ref> It is located at the [[antipodal point|antipode]] of [[Argyre Planitia]], centered at {{Coord|46.7|117.5|globe:Mars}}.<ref name="USGS_Utopia_Planitia">{{cite web|title=Utopia Planitia|work=Gazetteer of Planetary Nomenclature|publisher=[[USGS Astrogeology Science Center]]|url=https://planetarynames.wr.usgs.gov/Feature/6260|access-date=2015-03-10}}</ref> It is also in the [[Casius quadrangle]], [[Amenthes quadrangle]], and the [[Cebrenia quadrangle]] of Mars. The region is in the broader [[North Polar Basin (Mars)|North Polar/Borealis Basin]] that covers most of the Northern Hemisphere of Mars.

The Utopia basin is  estimated to have formed around 4.3-4.1 billion years ago.<ref>{{Cite journal |last=Robbins |first=Stuart J. |date=2022-12-01 |title=Inconsistency between the Ancient Mars and Moon Impact Records of Megameter-scale Craters |journal=The Planetary Science Journal |volume=3 |issue=12 |pages=274 |doi=10.3847/PSJ/aca282 |doi-access=free |issn=2632-3338}}</ref><ref>{{Cite journal |last=Frey |first=Herbert |date=July 2008 |title=Ages of very large impact basins on Mars: Implications for the late heavy bombardment in the inner solar system |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2008GL033515 |journal=Geophysical Research Letters |language=en |volume=35 |issue=13 |doi=10.1029/2008GL033515 |issn=0094-8276}}</ref> The impactor was likely around {{Convert|400-700|km}} in diameter.<ref>{{Cite journal |last=Arkani-Hamed |first=Jafar |date=April 2005 |title=Giant impact basins trace the ancient equator of Mars |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2004JE002343 |journal=Journal of Geophysical Research: Planets |language=en |volume=110 |issue=E4 |doi=10.1029/2004JE002343 |issn=0148-0227}}</ref><ref>{{Cite journal |last1=Ruedas |first1=Thomas |last2=Breuer |first2=Doris |date=May 2018 |title="Isocrater" impacts: Conditions and mantle dynamical responses for different impactor types |url=https://linkinghub.elsevier.com/retrieve/pii/S0019103517305961 |journal=Icarus |language=en |volume=306 |pages=94–115 |doi=10.1016/j.icarus.2018.02.005|arxiv=1802.08578 }}</ref><ref>{{Cite journal |last=Branco |first=Hely C. |last2=Miljkovic |first2=Katarina |last3=Plesa |first3=Ana‐Catalina |date=April 2024 |title=New Numerically Derived Scaling Relationships for Impact Basins on Mars |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023JE008217 |journal=Journal of Geophysical Research: Planets |language=en |volume=129 |issue=4 |doi=10.1029/2023JE008217 |issn=2169-9097|doi-access=free }}</ref> The basin was subsequently mostly filled in, resulting in a [[mascon]] (a strong positive [[gravity anomaly]]) detectable by orbiting satellites.<ref>{{Cite journal |last1=Klokočník |first1=Jaroslav |last2=Kletetschka |first2=Gunther |last3=Kostelecký |first3=Jan |last4=Bezděk |first4=Aleš |date=December 2023 |title=Gravity aspects for Mars |url=https://linkinghub.elsevier.com/retrieve/pii/S0019103523003068 |journal=Icarus |language=en |volume=406 |pages=115729 |doi=10.1016/j.icarus.2023.115729|url-access=subscription }}</ref><ref>{{Cite journal |last1=Searls |first1=Mindi L. |last2=Banerdt |first2=W. Bruce |last3=Phillips |first3=Roger J. |date=August 2006 |title=Utopia and Hellas basins, Mars: Twins separated at birth |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2005JE002666 |journal=Journal of Geophysical Research: Planets |language=en |volume=111 |issue=E8 |doi=10.1029/2005JE002666 |issn=0148-0227|url-access=subscription }}</ref>

Many rocks at Utopia Planitia appear perched, as if wind removed much of the soil at their bases.<ref>Mutch, T. et al. 1976. "The Surface of Mars: The View from the Viking 2 Lander". ''Science'': 194. 1277–1283.</ref><ref>Hartmann, W. 2003. ''A Traveler's Guide to Mars''. Workman Publishing. New York.</ref> A hard surface crust is formed by solutions of minerals moving up through soil and evaporating at the surface.<ref>Arvidson, R. A. Binder, and K. Jones. 1976. "The Surface of Mars". ''Scientific American'': 238. 76–89.</ref> Some areas of the surface exhibit [[scalloped topography]], a surface that looks like it was carved out by an ice cream scoop. This surface is thought to have formed by the degradation of an ice-rich permafrost.<ref>Sejourne, A. et al. 2012. Evidence of an eolian ice-rich and stratified permafrost in Utopia Planitia, Mars. Icarus. 60:248–254.</ref> Many features that look like [[pingos]] on the Earth are found in Utopia Planitia (~35–50° N; ~80–115° E).<ref>Soare, E., et al. 2019.
Possible (closed system) pingo and ice-wedge/thermokarst complexes at the mid latitudes of Utopia Planitia, Mars. Icarus. {{doi|10.1016/j.icarus.2019.03.010}}</ref>

On November 22, 2016, NASA reported finding a large amount of [[Water on Mars|underground ice]] in the Utopia Planitia region. The volume of water detected has been estimated to be equivalent to the volume of water in [[Lake Superior]].<ref name="NASA-20161122">{{cite web |author=Staff |title=Scalloped Terrain Led to Finding of Buried Ice on Mars |url=http://photojournal.jpl.nasa.gov/catalog/PIA21136 |date=November 22, 2016 |work=[[NASA]] |access-date=November 23, 2016 }}</ref><ref name="Register-2016">{{cite web|url=https://www.theregister.co.uk/2016/11/22/nasa_finds_ice_under_martian_surface/ |title=Lake of frozen water the size of New Mexico found on Mars – NASA |publisher=The Register|date=November 22, 2016 |access-date=November 23, 2016}}</ref><ref name="NASA-20161122jpl">{{cite web|url=http://www.jpl.nasa.gov/news/news.php?release=2016-299 |title=Mars Ice Deposit Holds as Much Water as Lake Superior |publisher=NASA|date=November 22, 2016 |access-date=November 23, 2016}}</ref>

==Scalloped topography==
{{Main|Scalloped topography|Water on Mars}}
{{multiple image
| direction = horizontal
| caption_align = center
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| total_width = 800
| header = Utopia Planitia<br />Scalloped terrain led to the discovery of a large amount of underground ice<br />enough water to fill Lake Superior<ref name="NASA-20161122" /><ref name="Register-2016" /><ref name="NASA-20161122jpl" />
| header_align = center
| image1 = PIA21136 - Scalloped Terrain Led to Finding of Buried Ice on Mars.jpg
| caption1 = Martian terrain
| width1 = 640
| height1 = 398
| image2 = PIA21138 - Location of Large Subsurface Water-Ice Deposit in Utopia Planitia, Mars.png
| caption2 = Map of terrain
| width2 = 596
| height2 = 286
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[[Scalloped topography]] is common in the [[mid-latitudes]] of Mars, between 45° and 60° north and south. It is particularly prominent in the region of Utopia Planitia<ref name=ref1>{{cite journal | last1=Lefort | first1=A. | last2=Russell | first2=P. S. | last3=Thomas | first3=N. | last4=McEwen | first4=A. S. | last5=Dundas | first5=C. M. | last6=Kirk | first6=R. L. | title=Observations of periglacial landforms in Utopia Planitia with the High Resolution Imaging Science Experiment (HiRISE) | journal=Journal of Geophysical Research | volume=114 | issue=E4 | year=2009 | pages=E04005 | doi=10.1029/2008JE003264 | bibcode=2009JGRE..114.4005L| url=https://boris.unibe.ch/36929/ | doi-access=free }}</ref><ref>{{cite journal|last1=Morgenstern|first1=A|last2=Hauber|first2=E|last3=Reiss|first3=D|last4=van Gasselt|first4=S|last5=Grosse|first5=G|last6=Schirrmeister|first6=L|year=2007|title=Deposition and degradation of a volatile-rich layer in Utopia Planitia, and implications for climate history on Mars|url=https://epic.awi.de/id/eprint/16592/1/Mor2007e.pdf|journal=Journal of Geophysical Research: Planets|volume=112|issue=E6|page=E06010|doi=10.1029/2006JE002869|bibcode=2007JGRE..112.6010M|doi-access=free}}</ref> in the northern hemisphere and in the region of [[Peneus]] and Amphitrites Patera<ref>{{cite journal | last1=Lefort | first1=A. | last2=Russell | first2=P.S. | last3=Thomas | first3=N. | title=Scalloped terrains in the Peneus and Amphitrites Paterae region of Mars as observed by HiRISE | journal=Icarus | volume=205 | issue=1 | page=259 | year=2010 | doi=10.1016/j.icarus.2009.06.005 | bibcode = 2010Icar..205..259L }}</ref><ref>{{cite journal | last1=Zanetti |first1= M. |last2= Hiesinger |first2=H. |last3= Reiss |first3= D. |last4= Hauber |first4= E. |last5= Neukum |first5= G. |year=2009 |url=http://www.lpi.usra.edu/meetings/lpsc2009/pdf/2178.pdf | title=Scalloped Depression Development on Malea Planum and the Southern Wall of the Hellas Basin, Mars | volume=40| journal= Lunar and Planetary Science |at= p. 2178, abstract 2178 | bibcode = 2009LPI....40.2178Z }}</ref> in the southern hemisphere. Such topography consists of shallow, rimless depressions with scalloped edges, commonly referred to as scalloped depressions or simply {{Em|scallops}}. Scalloped depressions can be isolated or clustered and sometimes seem to coalesce. A typical scalloped depression displays a gentle equator-facing slope and a steeper pole-facing scarp. This topographic asymmetry is probably due to differences in [[insolation]]. Scalloped depressions are believed to form from the removal of subsurface material, possibly interstitial ice, by [[Sublimation (phase transition)|sublimation]]. This process may still be happening at present.<ref>{{Cite web|url=https://hirise.lpl.arizona.edu/PSP_007173_2245|title=HiRISE &#124; Scallops and Polygons in the Utopia Planitia (PSP_007173_2245)|website=hirise.lpl.arizona.edu}}</ref>

==In popular culture==
In the ''[[Star Trek]]'' media franchise, Utopia Planitia—both on Mars's surface and a [[space station]] in [[areosynchronous orbit]] above it—is the site of a major [[United Federation of Planets]] shipyard, the Utopia Planitia Fleet Yards. Ships such as the [[USS Enterprise (NCC-1701-D)|USS ''Enterprise''-D]], [[USS Defiant|USS ''Defiant'']], [[USS Voyager (Star Trek)|USS ''Voyager'']] and [[USS Sao Paulo|USS ''Sao Paulo'']] were built there.<ref name="Encyc">{{cite book |last=Okuda |first=Michael |title=[[The Star Trek Encyclopedia]] |author2=Denise Okuda |author3=Debbie Mirek |date=1999 |publisher=[[Pocket Books]] |isbn=0-671-53609-5 |author-link=Michael Okuda |name-list-style=amp}}</ref>

==See also==
* [[Glaciers on Mars]]
* [[Geography of Mars]]
* [[List of plains on Mars]]
* [[Scalloped topography]]

==Notes==
{{Notelist}}

==References==
{{Reflist|colwidth=30em}}

==External links==
* [http://www.solarviews.com/cap/mgs/mgstopo8.htm Laser altimetry of the north pole of Mars] Utopia Planitia located in upper right
* [http://www.google.com/mars/#lat=48.806863&lon=115.3125&q=Utopia%20Planitia Google Mars scrollable map] – centered on Utopia Planitia
* [https://web.archive.org/web/20041103212240/http://cmex-www.arc.nasa.gov/SiteCat/sitecat2/vikings2.htm VL2 Site: Utopia Planitia (NASA)]
* [http://photojournal.jpl.nasa.gov/catalog/PIA00576 PIA00576: Martian Sunrise at Utopia Planitia (NASA Photojournal)]
* [http://photojournal.jpl.nasa.gov/catalog/PIA00530 PIA00530: Frost on Utopia Planitia (NASA Photojournal)]
* [http://photojournal.jpl.nasa.gov/catalog/PIA03796 PIA03796: Utopia Planitia (NASA Photojournal)]

{{Geography of Mars}}
{{Viking and Mars Pathfinder}}
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[[Category:Albedo features on Mars]]
[[Category:Amenthes quadrangle]]
[[Category:Cebrenia quadrangle]]
[[Category:Impact craters on Mars|#]]
[[Category:Plains on Mars]]
[[Category:Star Trek locations]]