NASA bombarded the comet and launched 250,000 tons of water

A 370kg satellite hits the comet Comet Tempel 1 (Photo: thuntek)

On July 4, 2005, Deep Impact fired a 370-kilogram satellite straight into Comet Tempel 1, 14 km in diameter. The collision launched a number of materials, especially water that flew out for more than 60 days.

This result has just been published recently after American and British scientists watched on the Swift telescope, one of many telescopes closely monitoring this intentional collision. Swift X - ray figures show that a lot of water from comets has been launched and for a longer time than originally expected.

The researchers hope that the event will help them better understand the nature and composition of comets in the universe. This is the first time that a deliberate human-intentional collision has been investigated.

Dr Dick Willingale of the University of Leicester, who led the study on swift, said: "Swift has a very ingenious feature and very sharp cameras, so using it to observe a comet is very ideal".

Deep Impact fired a satellite on July 4, 2005 (Photo: cfa.harvard)