Dawn Discoveries

Series of time-lapse images of Ceres rotation taken by Hubble's advanced camera
The Astrophysical Journal Letters | October 2012

Water plays a key role in the evolution of terrestrial planets, and notably in the occurrence of Earth's oceans. However, the mechanism by which water has been incorporated into these bodies—including Earth—is still extensively debated. Here we report the detection of widespread 2.8 μm OH absorption bands on the surface of the asteroid Vesta by the VIR imaging spectrometer on board Dawn.

Combination of Hubble Space Telescope image of Vesta (top) and a composite image of Vesta's landscape from framing camera images (below)
December 15, 2011
San Francisco, California
Before last July, Vesta was only a series of modest images brought to us by the Hubble Space telescope, enough to tantalize and inspire the Dawn mission, but essentially an unexplored new world in our solar system.

Dawn Discoveries Archive: