Dawn captured the above image over Vesta’s northern hemisphere after the spacecraft completed its first passage over the dark side of the giant asteroid. It is northern hemisphere winter on Vesta now, so its north pole is in deep shadow. The Dawn science team is working to determine the significance of the distinct features in this image, which include large grooves or ridges extending for great distances around Vesta.
Meanwhile, NASA says it will host a news conference on Monday, August 1, to discuss the Dawn spacecraft’s successful orbit insertion around Vesta on July 15 and unveil the first full-frame images from Dawn’s framing camera.
Dawn will spend a year orbiting the body. Next stop on its itinerary will be an encounter with the dwarf planet Ceres.
Ceres and Vesta are the two most massive residents of the asteroid belt. Vesta is a rocky body, while Ceres is believed to contain large quantities of ice. The profound differences in geology between these two protoplanets that formed and evolved so close to each other form a bridge from the rocky bodies of the inner solar system to the icy bodies, all of which lay beyond in the outer solar system.
The below meteorite is a sample of the crust of the asteroid Vesta, which is only the third solar system object beyond Earth where scientists have a laboratory sample (the other extraterrestrial samples are from Mars and the Moon). The meteorite is unique because it is made almost entirely of the mineral pyroxene, common in lava flows. The meteorite was discovered on March 29, 1807 by Heinrich Wilhelm Olbers of Germany. Image credit: R. Kempton (New England Meteoritical Services).