Above is the dwarf planet Ceres as seen by the Hubble Space Telescope. 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)
NASA's Dawn mission will arrive at Ceres in March of 2015. Discovered in 1801, Ceres was then thought to be a planet, but has since been reclassified (in 2006) as a dwarf planet. Ceres is the closest of its class to the orbit of Earth, orbiting in the asteroid belt between Mars and Jupiter. Ceres bears many similarities to Jupiter's moon Europa and Saturn's moon Enceladus, both considered to be potential sources for harboring life.
Ceres is the most massive body in the asteroid belt, and larger than some of the icy moons scientists consider ideal for hosting life. It is twice the size of Enceladus, which may hold liquid water beneath its surface.
Unlike other asteroids, the Texas-sized Ceres is round, suggesting that it almost certainly formed in the early solar system. If it formed later, there would have been less ice available, and so Ceres would not be as rounded in shape.
Ceres' shape, size and total mass reveal it to be a body of very low density. Scientists suggest it might even have had a liquid ocean at one point in its history. Once difference between Ceres and other icy solar system bodies is that it's closer to the Sun. Ceres is close enough to feel the Sun's warmth, allowing its ice to melt and reform.
Exploring the interior of this dwarf planet could provide insight into the early solar system, especially locations where water and other volatiles might have existed. For this reason, Ceres is thought to be the key to understanding the history of water in the middle solar system.
Click here to read the full article online at Astrobiology Magazine.
Click here to learn more about NASA's Dawn mission to Vesta and Ceres.