Phobos, Mars’ small rocky moon, has been imaged closer than ever before by the European Space Agency’s Mars Express spacecraft. In the latest of its five month period orbital flybys, the Mars Express passed the moon at a distance of 67km, the closest any probe has managed in history. The results are equally as stunning, with these 4.4-metres per pixel images clearly showing the far side of Phobos, illuminating its crater-heavy, rocky nature.
The images also helped show where the Russian-led 2011 Phobos-Grunt mission to land on the moon, capture a soil sample and return it to Earth will land, clearly highlighting the two proposed landing points (see above image).
Phobos is an irregular body roughly 27 x 22 x 19km in size with a highly debated origin. Some astonomers believe that due to its surface characteristics, which are similar to the carbonaceous C-type asteroids, it was captured from this population and adapted through a yet unknown mechanism to its current orbit in the equatorial plane of Mars. Other hypotheses indicate that it formed around Mars and is a remnant of planetary formation.