Over the weekend,

the Dawn mission spacecraft entered an orbit around Vesta.  This is the first time we have put a spacecraft into orbit around a minor planet.  Dawn will study Vesta for the next year, before moving on to Ceres, the only body in the asteroid field which is larger.

Shortly after entering orbit, Dawn snapped the highest resolution photograph ever taken of Vesta.  This image was used to create the composite image on the left, showing eight different asteroids which have been visited by robotic spacecraft.  With its diameter of 530 kilometers, Vesta not only dwarfs the other asteroids but is massive enough for gravity to have forced it into a spherical shape.  This means that Vesta is not only an asteroid, but fits the IAU definition of a protoplanet, along with Pluto.

The Dawn mission is managed by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., for the agency’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. of Dulles, Va., designed and built the Dawn spacecraft. The framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. The German Aerospace Center (DLR) Institute of Planetary Research in Berlin made significant contributions in coordination with the Institute of Computer and Communication Network Engineering in Braunschweig. The framing camera project is funded by the Max Planck Society, DLR and NASA. JPL is a division of the California Institute of Technology in Pasadena.  More information about Dawn is online at http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov