October 10, 2010
Scientists have found water ice on an asteroid for the second time in just six months.
The discovery suggests that such ice is more common on asteroids in our section of the solar system than previously thought – and that such asteroids may have delivered much of the essentials for early life to Earth.
Two research teams found evidence of water and organic molecules on asteroid 65 Cybele.
Six months ago the teams made a similar discovery on a different rock – asteroid 24 Themis – for the first time.
Published online April 28, 2010:
Cool discovery suggests asteroids brought water and organic material.
A slushy cocktail of water-ice and organic materials has been directly detected on the surface of an asteroid for the first time. The finding strengthens the theory that asteroids delivered the ingredients for Earth’s oceans and life, and could make astronomers rethink conventional models for how the Solar System evolved.
It has long been thought that asteroids, which lie in a belt between Mars and Jupiter, are rocky bodies that sit too close to the Sun to retain ice. By contrast, comets, which form further out beyond Neptune, are ice-rich bodies that develop distinctive tails of vaporized gas and dust when they approach the Sun. However, this distinction was blurred in 2006 by the discovery of small objects with comet-like tails in the asteroid belt1, says astronomer Andrew Rivkin of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.