From Wiki: Ceres (-planet designation 1 Ceres) is the object in the asteroid belt, which lies between the orbits of Mars and Jupiter. It is composed of rock and ice, is 950 km (590 mi) in diameter, containing a third of the mass of the asteroid belt. It is the asteroid, and the only dwarf planet in the inner Solar System.

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It’s only nine pixels wide, but the probe’s latest picture of Ceres already shows that the dwarf planet is to form.
The Dec. 1 was taken when NASA’s Dawn spacecraft was about 740,000 miles (1.2 million kilometers) from 590-mile-wide (950-kilometer-wide) Ceres, the most massive object in the main asteroid belt. Dawn is on its way to a rendezvous with Ceres early next year after studying Vesta, the second most massive asteroid.
The Astronomical Union lumped Ceres in with Pluto and several other worlds as dwarf planets in 2006 — to the fact that it’s massive enough to maintain a round , but not enough to “clear the neighborhood of its orbit.” That definition may be a problematic; nevertheless, Dawn’s view certainly provides a sense of Ceres’ roundness. 
Location of Ceres
This picture was taken primarily to calibrate Dawn’s camera. It’s not as detailed as the view that the Hubble Space Telescope captured in 2004. For better views — perhaps including glimpses of ice caps, ice volcanoes and clouds — check back in March, when Dawn goes into orbit around the first dwarf planet to be seen up.