The Cliffs of Comet ChuryumovGerasimenko

Explanation: These high cliffs occur on the surface of a comet. They were discovered to be part of the dark nucleus of Comet ChuryumovGerasimenko (CG) by Rosetta , a robotic spacecraft launched by ESA which began orbiting the comet in early August. The ragged cliffs, as featured here , were imaged by Rosetta about two weeks ago. Although towering about one kilometer high, the low surface gravity of Comet CG would likely make a jump from the cliffs , by a human, survivable. At the foot of the cliffs is relatively smooth terrain dotted with boulders as large as 20 meters across. Data from Rosetta indicates that the ice in Comet CG has a significantly different deuterium fraction -- and hence likely a different origin -- than the water in Earth's oceans. The Rosetta spacecraft is scheduled to continue to accompany the comet as it makes its closest approach to the Sun in 2015 August.