The color explosions of the auroras fascinate just about everyone. Often in shades of green, sometimes red-violet-pink or bluish, they race or dance across the skies of the polar regions under the right conditions. Responsible for auroras are electrically charged...
Mercury North Pole with yellow marked water ice deposits. (Photo: NASA/ MESSENGER) It seems almost paradoxical: there is water ice on Mercury, which is heated by the nearby sun. This ice remains in the deep permanent shadow of some polar craters. Until now, meteorite...