Deseado Crater is a large

Hesperian The Hesperian is a system (stratigraphy), geologic system and geologic timescale, time period on the planet Mars characterized by widespread Volcanology of Mars, volcanic activity and catastrophic flooding that carved immense outflow channels acr ...

- or Amazonian-age

impact crater An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters ...

in Promethei Planum near the

south pole The South Pole, also known as the Geographic South Pole, Terrestrial South Pole or 90th Parallel South, is one of the two points where Earth's axis of rotation intersects its surface. It is the southernmost point on Earth and lies antipod ...

of Mars, within the

Mare Australe quadrangle The Mare Australe quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Mare Australe quadrangle is also referred to as MC-30 (Mars Chart-30). The quadr ...

, due south of the Hellas impact basin. It is named for

Puerto Deseado Puerto Deseado, originally called Port Desire, is a city of about 15,000 inhabitants and a fishing port in Patagonia in Santa Cruz Province of Argentina, on the estuary of the Deseado River. It was named ''Port Desire'' by the privateer Thomas C ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

. The crater contains a central topographic high interpreted to be an ice mound of probable Amazonian age. Despite the proximity of the ice mound to the southern polar ice sheet, it is not interpreted to have initially been a part of it. Deseado Crater features in the ''

Mass Effect ''Mass Effect'' is a military science fiction media franchise created by Casey Hudson, Drew Karpyshyn and Preston Watamaniuk. The franchise depicts a distant future where humanity and several alien civilizations have colonized the known univers ...

'' trilogy as the home of a structure constructed by a species called the Protheans to study the evolution of early humans.

Context

Deseado Crater is a southern polar crater on Mars located in Promethei Planum near the

Planum Australe Planum Australe (Latin: "the southern plain") is the southern polar plain on Mars. It extends southward of roughly 75°S and is centered at . The geology of this region was to be explored by the failed NASA mission Mars Polar Lander, which lost co ...

plateau (at the south pole), south of the Hellas impact basin. The crater is cartographically situated within the

. It is located north of Chasma Australe and Australe Lingula, respectively a canyon and a lobate promontory of Planum Australe. The crater, which has a diameter of 27.8 km and a maximum depth of 1.44 km, is immediately adjacent to the edge of the Southern Polar Layered Deposit (SPLD), a geologic unit constituting Mars’ southern polar ice sheet interpreted to be alternating layers of dust and ice. The crater is named for

, a town in

. The name was officially approved by the

International Astronomical Union The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreac ...

in 2006.

Popular culture

Deseado Crater is referenced in the ''

'' series as the location of an extraterrestrial installation operated by an ancient spacefaring species called the Protheans. The alien species used Deseado Crater as a base to observe the evolution of Cro-Magnon humans on Earth. Archives in the crater's base contained information that ultimately permitted humanity to develop faster-than-light travel.

Geology

Deseado Crater was emplaced on a flat low-lying (possibly lava-formed) plain associated with the Dorsa Argentea Formation. It has been dated to the

or, more recently, to the Amazonian period by different researchers. The center of Deseado Crater contains a central terraced dome that is hypothesized to be a large ice mound. This feature is separate from, but near to the periphery of, the main southern polar ice sheet. The feature was initially interpreted to represent an outlying extension of the main ice sheet and is likely to be much younger than the crater itself, perhaps of late Amazonian age. However, the lack of flow features in the impact basin suggests that the Deseado ice mound is probably an ''in situ'' feature rather than migrating material that was separated from the main ice sheet. The central ice mound is also biased to the west of the impact basin's true center, a common feature in ice-mound-bearing craters with high aspect ratios (diameter to depth). This asymmetry has been interpreted to be caused by the

Coriolis effect In physics, the Coriolis force is an inertial or fictitious force that acts on objects in motion within a frame of reference that rotates with respect to an inertial frame. In a reference frame with clockwise rotation, the force acts to the ...

, which deflects

katabatic wind A katabatic wind (named from the Greek word κατάβασις ''katabasis'', meaning "descending") is a drainage wind, a wind that carries high-density air from a higher elevation down a slope under the force of gravity. Such winds are sometim ...

s to the west in the Martian southern hemisphere. Other than viscous flow features, the Deseado ice mound does not exhibit clear layering, edge ridges, stacked mounds, or sand dune seas. These other features have been reported in craters of similar morphologies.

References

{{reflist, refs= {{cite map , first1 = K. L. , last1=Tanaka, first2=D. H., last2=Scott, title = Geologic map of the polar regions of Mars , trans-title = , map = , map-url = , date =1987 , year = , url = https://pubs.er.usgs.gov/publication/i1802C , scale = 1:9,203,425 , series = Investigations Map 1802-C , publisher = United States Geological Survey , cartography = , page = , pages = , section = , sections = , inset = , edition = , location = , language = , format = , isbn = , id = , access-date = , archive-url = , archive-date = {{cite journal , last1=Sori , first1=M. M. , last2=Bapst , first2=J. , last3=Becerra , first3=P. , last4=Byrne , first4=S. , date=2019 , title=Islands of ice on Mars and Pluto , url= , journal=Journal of Geophysical Research: Planets , volume=124 , issue= 10, pages=2522–2542 , doi= 10.1029/2018JE005861 , bibcode=2019JGRE..124.2522S , hdl=10150/636169 , access-date=, hdl-access=free {{cite thesis , last=Westbrook , first=O. W. , date=2009 , title=Crater ice deposits near the South Pole of Mars , type=Master’s thesis , chapter= , publisher=Massachusetts Institute of Technology , docket= , oclc= , url= , access-date= {{cite video game, title=

, developer=

Bioware BioWare is a Canadian video game developer based in Edmonton, Alberta. It was founded in 1995 by newly graduated Doctor of Medicine, medical doctors Ray Muzyka, Greg Zeschuk and Augustine Yip, alongside Trent Oster, Brent Oster, and Marcel Zes ...

, platform=

Xbox 360 The Xbox 360 is a home video game console developed by Microsoft. As the successor to the original Xbox, it is the second console in the Xbox series. It competed with Sony's PlayStation 3 and Nintendo's Wii as part of the seventh generation ...

, level=Codex (Secondary): Mars Ruins, quote= In 2148, prospectors working near Deseado Crater discovered an underground complex: a Prothean observation post. {{cite journal , last1=Milkovich , first1=S. M. , last2=Plaut , first2=J. J. , date=2008 , title=Martian South Polar Layered Deposit stratigraphy and implications for accumulation history , url= , journal= Journal of Geophysical Research, volume=113 , issue=E06007 , pages= E06007, doi=10.1029/2007JE002987 , bibcode=2008JGRE..113.6007M , access-date=, doi-access=free {{cite web , url=https://planetarynames.wr.usgs.gov/Feature/1500?__fsk=470642075 , title=Gazetteer of Planetary Nomenclature: Deseado , author= , date=2010 , website= , publisher=

, access-date=23 May 2021 , quote= Impact craters on Mars Plains on Mars