Asteroid debris offers new clues to how water reached Earth

COVENTRY, England, May 7 (UPI) -- Most scientists agree, asteroids played a major role in delivering the building blocks of life to a newly formed Earth, including water.

But are the same processes taking place elsewhere in the galaxy? All over the universe?

A new study, published by the Royal Astronomical Society, suggests the process that brought Earth its water isn't necessarily unique. In fact, researchers say, asteroids are likely delivering water throughout the cosmos.

Recently, while observing a white dwarf called SDSS J1242+5226, astronomers at Warwick University detected large quantities of hydrogen and oxygen.

Their calculations suggested the elements had been delivered by a massive water-rich exo-asteroid -- measuring roughly 560 miles across and comparable in size to Ceres, the largest asteroid in our solar system. Scientists' estimates suggest the exo-asteroid was carrying enough water to replace a third of the water in Earth's oceans.

"Our research has found that, rather than being unique, water-rich asteroids similar to those found in our solar system appear to be frequent," Roberto Raddi, an astrophysicist at Warwick, explained in a press release. "Accordingly, many planets may have contained a volume of water, comparable to that contained in the Earth."

"It is believed that the Earth was initially dry, but our research strongly supports the view that the oceans we have today were created as a result of impacts by water-rich comets or asteroids," Raddi added.

Raddi's colleague and co-author of the new study, Boris Gansicke, said that because oxygen is relatively heavy, it will eventually sink down into the lower atmosphere and disappear from view. In contrast, hydrogen will continue to float in the white dwarf's upper atmosphere long after the disruption event.

"There are many white dwarfs that hold large amounts of hydrogen in their atmospheres, and this new study suggests that this is evidence that water-rich asteroids or comets are common around other stars than the Sun," Gansicke explained.