New pictures of Mars released this week shed light on the composition of the planet’s polar ice cap, reveal and odd dust storm embedded in a volcano’s crater, and show a strangely off-center impact crater. The pictures were produced by the Mars Orbiter Camera on NASA’s Mars Global Surveyor spacecraft, which this month began its second year of an extended mission. One of the newly released pictures has helped researchers better understand how sand and dust mix with water ice on the Red Planet.