Nasa has announced that it will officially retire the ageing Space Shuttle fleet by 2010, four years before it will have a replacement craft ready.

The Space Shuttle fleet will make 10 more flights, mainly to add modules to the International Space Station and carry out repairs and upgrades to the Hubble telescope.

The retirement will leave the US without an orbital capacity for at least four years, until the Ares booster programme is complete. European and Russian launchers will service the Space Station in the meantime.

The replacement systems will include the Ares I rocket which will deliver crew to the station, and the Ares V heavy lifter which will carry 130,000kg of cargo on each trip and will eventually be used for a planned Moon landing in 2020.

The Shuttle programme was signed off in 1972 by then president Richard Nixon and was the first attempt to build a reusable craft that would cut the cost of moving equipment into space.

Each craft carries a crew of seven and a payload of 22,000kg.

Originally four Shuttles were planed: Columbia, Challenger, Discovery and Atlantis. However, after the destruction of Challenger in 1986 a new shuttle, Endeavour, was built out of spare parts. Columbia was lost on re-entry in 2003.