... Thirty Thousand Kilometers Above Enceladus . ... What does the surface of Saturn's ice-spewing moon Enceladus look like? ... Endeavour to Orbit . ... Eta Carinae, one of the most massive and unstable stars in the Milky Way Galaxy, has a profound effect on its environment. ... An Avalanche on Mars . ... What caused this sudden cloud of dust on Mars? ... The first avalanche imaged in progress on another planet was recorded last month on Mars by NASA's robotic Mars Reconnaissance Orbiter. ...