On Monday, NASA and the Jet Propulsion Laboratory released the first full-frame images of the asteroid Vesta, taken by the Dawn spacecraft from a distance of about 3,200 miles.
Vesta is the brightest object in the asteroid belt between Mars and Jupiter, as seen from Earth. It has a surface area approximately twice that of California's and is 330 miles in diameter. Scientists are interested in what they've been calling "the smallest terrestrial planet" because they think its rocky surface may reveal what was happening in the earliest days of the solar system.
Studies by the Hubble Space Telescope revealed that the southern part of the asteroid was damaged by a large impact, and Monday's images show that indeed, Vesta's south hemisphere has a much smoother, less-cratered terrain than the area north of its equator. The impact created a huge crater and debris, and was of such magnitude that it smoothed out Vesta's southern surface, erasing the effects of earlier impacts that are still visible in the north.
Further details are expected as Dawn enters into the first of four science orbits. Scientists are excited by the nonuniformity of Vesta's surface, which indicates that the asteroid isn't just a homogenous rock in space.
Dawn will spend a year orbiting Vesta before firing its unique ion engines to depart for Ceres, another celestial body that scientists believe will aid in our understanding of the formation of our solar system and terrestrial planets. Dawn will be the first spacecraft targeted to orbit any two solar system destinations and is scheduled to arrive at Ceres in 2015, eight years after its launch.