The 2001 Mars Odyssey spacecraft snapped this image of Olympus Mons, the tallest volcano in the solar system, in March. NASA released the image in late June as the spacecraft completed orbit number 100,000 around Mars. Most of the craft’s pictures are shot straight down, but for this one, controllers turned Odyssey to look to the side. That revealed the distinct layers in the Martian atmosphere, which are produced by combinations of sand and clouds. [NASA/JPL/ASU]