The semi-major axis of Ceres' orbit about the Sun is 2.77 Astronomical Units (A.U.) or roughly 257 million miles (414 million kilometers). At the time of the Hubble observations, Ceres was roughly 1.63 A.U. from Earth.
Ceres is has a mean diameter of approximately 590 miles (950 kilometers). The object has a 974.6 km diameter at the equator and a slightly smaller diameter (909.4 km) pole-to-pole.
This image was created from data from the HST proposal 9748: J. Parker (Southwest Research Institute), L. McFadden (University of Maryland), C. Russell (University of California, Los Angeles), A. Stern (Southwest Research Institute), M. Sykes (University of Arizona), P. Thomas (Cornell University) and E. Young (Southwest Research Institute).
NASA, ESA, J. Parker (Southwest Research Institute), P. Thomas (Cornell University), L. McFadden (University of Maryland, College Park), and M. Mutchler and Z. Levay (STScI)
This image is a composite of many separate exposures made by the ACS HRC instrument on the Hubble Space Telescope using several different filters. Two filters were used to sample broad wavelength ranges. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are:
NASA, ESA, J. Parker (Southwest Research Institute), P. Thomas (Cornell University), L. McFadden (University of Maryland, College Park), and M. Mutchler and Z. Levay (STScI)
