Water delivery via asteroids or comets is most likely taking place in many other planetary systems just as it happened on Earth, British astronomers say.
A team from University of Warwick has found a fresh evidence that numerous planetary bodies, including asteroids and comets, contain large quantities of water.
The discovery adds further support to the possibility that water can be delivered to Earth-like planets via such bodies to create a suitable environment for life.
"We found that rather than being unique, water-rich asteroids similar to those found in our solar system appear to be frequent. Accordingly, many of planets may have contained a volume of water, comparable to that contained in the Earth," said lead researcher Roberto Raddi.
"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'," he explained.
In observations obtained at the William Herschel Telescope in the Canary Islands, the astronomers detected a large quantity of hydrogen and oxygen in the atmosphere of a white dwarf star known as SDSS J1242+5226.
The quantities found provide the evidence that a water-rich exo-asteroid was disrupted and eventually delivered the water it contained onto the star.
The asteroid was comparable in size to Ceres - at 900 km across and the largest asteroid in our solar system.
"The amount of water found is equivalent to 30-35 percent of the oceans on Earth," Raddi added.
The impact of water-rich asteroids or comets onto a planet or dwarf star results in the mixing of hydrogen and oxygen into the atmosphere.
Both elements were detected in large amounts in SDSS J1242+5226. The research was published in the journal Monthly Notices of the Royal Astronomical Society.
