NASA's
Dawn spacecraft is now less than a year away from giant asteroid Vesta. Today's story from Science@NASA offers a sneak preview of an "alien, unexplored world" that seems sure to amaze.
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http://science.nasa.gov/science-news/science-at-nasa/2010/19aug_dawn2/
Vesta, formal designation 4 Vesta, is an asteroid, thought to be a remnant protoplanet, with a mean diameter of about 530 km.[1] Comprising an estimated 9% of the mass of the entire asteroid belt,[10] it is the second most massive object in the belt (the largest being the dwarf planet Ceres). It was discovered by the German astronomer Heinrich Wilhelm Olbers on March 29, 1807[1] and named after the Roman virgin goddess of home and hearth, Vesta.
Vesta is the brightest asteroid. Its greatest distance from the Sun is slightly more than the minimum distance of Ceres from the Sun,[11] and its orbit is entirely within the orbit of Ceres.[12] Vesta lost some 1% of its mass in a collision less than one billion years ago. Many fragments of this event have fallen to Earth as Howardite-Eucrite-Diogenite (HED) meteorites, a rich source of evidence about the asteroid.[13]
