A NASA spaceship, its engines too weak to power a skateboard, is drawing closer to a never-visited dwarf planet in a quest to learn more about how Earth was formed.
Dawn, a golf-cart-size NASA probe launched seven years ago, is on its way to rendezvous with Ceres, a minor planet as big across as Texas, on March 6. A rocky globe in the asteroid belt that probably holds a reservoir of ice, Ceres may provide keys to understanding what our own planet was like at the very beginning of its formation.
Once Dawn reaches Ceres, it will be the first spacecraft to orbit two celestial bodies on a single voyage, with a mission to study the formation of the solar system. Until 2012, Dawn had been circling Vesta, an asteroid whose core resembles our planet's and whose surface was so shattered by impacts that the resulting meteorites have found their way to our planet. Vesta and Ceres are the two largest objects in the asteroid belt between Mars and Jupiter.