... Comet NEAT Passes an Erupting Sun . ... Just as the comet swooped inside the orbit of Mercury and developed a long and flowing tail of gas and dust, the Sun emitted a huge Coronal Mass Ejection (CME). ... This delightfully detailed false-color image of Saturn was taken in January 1998 by the orbiting Hubble Space Telescope. ... Melting Snow and the Gullies of Mars . ... But Mars is too cold and its atmosphere too thin for liquid water to exist on the surface. ... The planet Mercury resembles a moon....