Largest Asteroid May Be 'mini Planet' With Water Ice

Technical facts about this news release: About the Object Object Name: Ceres, 1 Ceres Object Description: Minor Body in the Main Asteroid Belt Distance: 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. Dimensions: 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. About the Data Data Description: 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). Instrument: ACS/HRC Exposure Date(s): December 2003 - January 2004 Filters: F330W ("U") and F555W ("V") About the Image Image Credit: 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) Release Date: September 7, 2005 Color: 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: F330W ("U") blue F555W ("V") red/orange Orientation/Scale: Color View of Ceres [ http://imgsrc.hubblesite.org/hu/db/2005/27/images/d/formats/compass_large_web.jpg ] *News Release Number:*: STScI-2005-27f