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{{Infobox crater data
| titlecolor = #FA8072
| title = Zunil
| region = [[Athabasca Valles]]▼
| image = Zunil crater as seen by CTX (cropped).jpg
| diameter = 10.4 km▼
| alt = Zunil crater as seen by CTX
▲| region = [[Athabasca Valles]]
| coordinate_title = [[Mars#Geography|Coordinates]]
|
| coordinates = {{coord|7.8|N|193.9|W|globe:mars_type:landmark|display=inline,title}}
| eponym = [[Zunil]]▼
▲| eponym = [[Zunil]], Guatemala
}}
'''Zunil''' is an [[impact crater]] near the [[Cerberus Fossae]] on [[Mars]], with a diameter of {{convert|10.
A ray system associated with the Zunil impact, visible in infrared images from the Mars Odyssey [[Thermal Emission Spectrometer]] (THEMIS) was later detailed by McEwen et al. (2003);
The debris from a recent landslide was first spotted on the south-east wall of the crater by the Mars Global Surveyor Mars Orbiter Camera (MOC) in 2003,<ref>{{cite web|url=http://www.msss.com/moc_gallery/r03_r09/images/R08/R0802140.html|title=MOC narrow-angle image R08-02140—Zunil Crater and its ejecta|publisher=Malin Space Science Systems|
== Formation ==
The impact which formed Zunil occurred no more than a few million years ago and hence the crater is in a relatively pristine form. It was probably not produced in a high velocity impact, such as from a comet. The crater formed in basalt deposited 165 - 177 million years ago.<ref name=icarus />▼
▲The impact which formed Zunil occurred no more than a few million years ago and hence the crater is in a relatively pristine form. It was probably not produced in a high
The impact created a [[ray system]], visible in the [[infrared]], that extends up to 1600 km from the crater and produced hundreds of millions of [[secondary crater]]s with diameters ranging from 10 m to 100 m. Very few of these secondary craters lie within 80 km of Zunil. Around 80% of the craters in [[Athabasca Valles]] are Zunil secondaries. If similar impacts also produced comparable amounts of secondaries, this calls into question the accuracy of [[crater counting]] as a dating technique for geologically young Martian surface features.<ref name=icarus>{{cite journal|author=McEwen, A.S. et al.|url=http://www.mars.asu.edu/christensen/classdocs/mcewen_zunil_Icarus_2005.pdf|title=The rayed crater Zunil and interpretations of small impact craters on Mars|journal=[[Icarus (journal)|Icarus]]|volume=176|pages=351–381|year=2005|accessdate=2006-09-08|doi=10.1016/j.icarus.2005.02.009|bibcode=2005Icar..176..351M}}</ref><ref name=science>{{cite journal|title=Who can Read the Martian Clock?|journal=[[Science (journal)|Science]]|author=Kerr, R|volume=312|year=2006|pages=1132–1133|doi=10.1126/science.312.5777.1132|pmid=16728612|issue=5777}}</ref>▼
A simulation of the Zunil impact ejected on the order of ten billion rock fragments greater than 10 centimeters in diameter, the total ejecta comprising 30 km<sup>3</sup>. These formed about a billion secondary craters 10 m in size up to 3500 km away from the primary impact. It is possible that some of these fragments from the impact made it to Earth to become shergottites, a form of [[Martian meteorite]].<ref name=icarus />▼
▲The impact created a [[ray system]], visible in the [[infrared]], that extends up to
==See also==▼
▲[[Image:Landslide on Mars.jpg|thumb|200px|right|A landslide in the Martian crater Zunil.]]
*[[List of craters with ray systems]]▼
▲A simulation of the Zunil impact ejected on the order of ten billion rock fragments greater than {{convert|10
==References==▼
Research published in the journal ''Icarus'' has found pits in Zunil Crater that are caused by hot ejecta falling on ground containing ice. The pits are formed by heat forming steam that rushes out from groups of pits simultaneously, thereby blowing away from the pit ejecta.<ref>Tornabene, L. et al. 2012. "Widespread crater-related pitted materials on Mars. Further evidence for the role of target volatiles during the impact process". ''Icarus''. 220: 348-368.</ref>
▲== See also ==
* [[List of craters on Mars]]
▲* [[List of craters with ray systems]]
▲== References ==
{{reflist}}
== External links ==
* [http://themis.asu.edu/
* [http://www.psrd.hawaii.edu/Jan07/MarsRayedCraters.html Rayed craters on Mars]
{{Geography of Mars}}
{{Portal bar|Solar System}}
[[Category:Impact craters on Mars]]
[[Category:Elysium quadrangle]]
[[Category:Extraterrestrial landslides]]
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