Deimos (moon): Difference between revisions

|accessdate = 2008-02-13

}}</ref> The two largest craters, [[Swift (Deimian crater)|Swift]] and [[Voltaire (crater)|Voltaire]], each measure about 3 kilometres across.

===Orbital===

Deimos' orbit is nearly circular and is close to Mars' [[equatorial plane]]. Mars' outer moon is possibly an asteroid that was perturbed by [[Jupiter]] into an [[orbit]] that allowed it to be captured by Mars, though this hypothesis is still controversial and disputed.<ref name= "burns"/> Both Deimos and Phobos have very circular orbits which lie almost exactly in Mars' equatorial plane, and hence a capture origin requires a mechanism for circularizing the initially highly eccentric orbit, and adjusting its inclination into the equatorial plane, most likely by a combination of atmospheric drag and [[tidal force]]s,<ref name="cazenave">{{cite journal |last=Cazenave |first=A. |authorlink= |coauthors=Dobrovolskis, A.; Lago, B. |year=1980 |month= |title=Orbital history of the Martian satellites with inferences on their origin |journal=Icarus |volume=44 |issue=3 |pages=730–744 |doi=10.1016/0019-1035(80)90140-2 |url= |accessdate= |quote= }}</ref> although it is not clear that sufficient time is available for this to occur for Deimos.<ref name="burns"/>