Asteroid may show how life came to Earth

Posted by Emma Woollacott

For the first time, water and organic molecules have been detected on an asteroid. The discovery lends plausibility to the theory that both  life on earth and water arrived through asteroid strikes.

University of Central Florida researchers found a thin layer of water ice and organic molecules on the surface of 24 Themis, the largest in a family of asteroids orbiting between Mars and Jupiter.

"What we've found suggests that an asteroid like this one may have hit Earth and brought our planet its water," said UCF physics professor Humberto Campins, the study's lead author.

Using NASA's Infrared Telescope Facility in Hawaii, Campins and his team of researchers measured the intensity of the reflected sunlight as 24 Themis rotated, indicating the makeup of the asteroid's surface.

They were surprised to find ice and carbon-based compounds evenly distributed on 24 Themis. More specifically, the discovery of ice was particularly unexpected, because the asteroids were believed to be too warm to maintain it.

The researchers plan to check out several hypotheses to explain the presence of ice. Perhaps most promising, they say, is the possibility that 24 Themis might have preserved the ice in its subsoil, just below the surface.

More detail appears in Nature.