Listen to an audio version of this page.

	Ceres
	When Ceres was first discovered it was called a comet. Within a year it was called a planet. Within one more year it was called an asteroid. Since 2006, it has been called a dwarf planet.

Ceres was discovered on January 1, 1801 by Italian Giuseppe Piazzi. He discovered it while searching for a star. Ceres is named after the goddess of growing plants, harvest, and motherly love. Piazzi originally named it Ceres Ferdinandea. Other astronomers around the world did not like the name, so it was changed to just Ceres. Ceres is 415 million kilometers from the Sun. It is located in the asteroid belt between Mars and Jupiter. From 1802 until 2006, Ceres was the largest known asteroid in our Solar System. About one-third of all the material (or mass) found in the asteroid belt was in Ceres! When the new class of dwarf planets was made in 2006, Ceres fit the definition perfectly. Ceres is now the smallest of the known dwarf planets. Ceres formed about 4.5 billion years ago when the solar system was forming. It is 950 kilometers wide. It is believed to have a rocky center. Scientists also believe it may have a liquid layer somewhere below the surface.

A Question If Ceres were to suddenly depart the asteroid belt, by what percentage would the mass of the belt be decreased?