Scientists have for the first time detected water-ice and organic compounds on an asteroid, a discovery which may offer insights into how life started on Earth.
They detected a significant amount of ice on a large asteroid called 24 Themis, which lies between Mars and Jupiter.
This adds weight to the theory that asteroids and comets crashing into the Earth billions of years ago seeded it with water and carbon-based molecules, which are essential ingredients for life.
Dr Josh Emery from the University of Tennessee is one of the astronomers who made the discovery.
First broadcast 29 April 2010