October 14, 2013
Using observations obtained with the Hubble Space Telescope and the large telescopes of the W. M. Keck Observatory, researchers found an excess of oxygen—a chemical signature that indicates that the debris had once been part of a bigger body originally composed of 26 percent water by mass.
Evidence for water outside our solar system has previously been found in the atmosphere of gas giants, but this is the first time it has been pinpointed in a rocky body, making it of significant interest in understanding of the formation and evolution of habitable planets and life.
The dwarf planet Ceres contains ice buried beneath an outer crust, and researchers have drawn a parallel between the two bodies. It’s believed that bodies like Ceres were the source of the bulk of our own water on Earth.