Water ice has been found on the surface of a nearby asteroid for the first time – a discovery that could help explain how Earth got its oceans, scientists announced.
Two teams of researchers independently verified that the asteroid 24 Themis – a large rock hurtling through space in the asteroid belt between Mars and Jupiter – is coated in a layer of frost.
They also found that the asteroid contains organic material, including some molecules that might be ingredients for life. But scientists have not found any evidence for life itself on this asteroid, or anywhere else in the universe beyond Earth.
“This is the first time we’ve actually seen ice – literally H20 – on an asteroid,” said one of the study leaders, Andrew Rivkin of Johns Hopkins University.
Previously, hints that water might be present on 24 Themis were found in the form of hydrated minerals, which were thought to have formed from the reaction of water with rock. But this time the researchers saw the direct signature of water itself, he explained.
Another science team, led by Humberto Campins of University of Central Florida, found the same thing. Both teams used the NASA Infrared Telescope Facility atop on Mauna Kea in Hawaii to make their observations, but conducted them on different nights.
“Our work and their work are very nicely confirming and complementary,” Campins said.
“To our surprise there was water ice, there were organic molecules, and they were more or less evenly distributed throughout the surface,” Campins told, “We thought that was fascinating.”
Both teams reported their findings in the 19 April 2010 issue of the journal Nature.