Washington, Jan 23
Scientists at the Herschel space observatory recently observed something unexpected - signs of water on a large asteroid.
Ceres, on whose surface vapours have been observed, is the largest and roundest object in the asteroid belt and is classified as a dwarf planet - a solar system body bigger than an asteroid and smaller than a planet.
Plumes of water vapour are thought to shoot up periodically from Ceres when portions of its icy surface warm slightly.
"This is the first time water vapour has been detected on Ceres or any other object in the asteroid belt and provides proof that Ceres has an icy surface and an atmosphere," said Michael Küppers of the European Space Agency (ESA) in Spain, lead author of a paper in the journal Nature.
In the last century, Ceres was known as the largest asteroid in our solar system. But in 2006, the International Astronomical Union, reclassified Ceres as a dwarf planet because of its large size. It is roughly 950 km in diameter.
Scientists believe Ceres contains rock in its interior with a thick mantle of ice that, if melted, would amount to more fresh water than is present on all of Earth.
By:IANS