A radar experiment aboard India's Chandrayaan-1 lunar spacecraft has identified thick deposits of water ice near the Moon's north pole. The US space agency's, Nasa, Mini-Sar experiment found more than 40 small craters containing water ice. But other compounds – such as hydrocarbons – are mixed up in lunar ice, according to new results from another lunar mission called LCROSS. The findings were presented at a major planetary science conference in Texas. Dr Paul Spudis, from the Lunar and Planetary Institute in Houston, estimated that there is at least 600 million metric tonnes of water ice held within them.