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The Winter 2010 issue of The Earth Scientist includes a variety of educational resources, ranging from astronomy to glaciers. Check out the other publications and classroom materials in our online store.
This picture of the asteroid Ceres was made by the Hubble Space Telescope in December 2003 and January 2004. Ceres was declared a "dwarf planet", along with Pluto and Eris, in 2006.
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Image courtesy of 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).

Ceres: Asteroid and Dwarf Planet

Ceres is the largest asteroid in the main asteroid belt. It was classified as a "dwarf planet" in 2006, along with Pluto and Eris. Ceres was discovered on January 1, 1801 by the Italian astronomer and monk Giuseppe Piazzi.

Ceres has a diameter of about 975 km (605 miles). It is by far the largest and most massive body in the main asteroid belt, and contains about a third of the belt's total mass. Ceres orbits the Sun once every 4.6 years. Its orbit lies between the orbits of Mars and Jupiter. The asteroid turns on its axis once every 9 hours, so that's how long a day is on Ceres.

Last modified November 28, 2007 by Randy Russell.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA