Space shuttle Discovery is set to take off on December 7 at 9:36 pm Eastern time (0236 GMT) from the Kennedy Space Centre. The planned space shot, which follows successful July and September missions, will mark NASA’s first night shuttle launch since the 2003 Columbia accident.

NASA required the three launches after the Columbia accident to be in daylight, so clear images could be taken of the space shuttle’s external fuel tank in case foam falls off it.

Foam breaking off the tank and striking Columbia’s wing at lift-off caused the damage that led to the disaster.

The space agency needs to start launching shuttles at night to finish space station construction by 2010, when the shuttle programme ends.

The external tanks had acceptable levels of foam loss during the last two lift-offs. (Sources: space.com and NDTV.com)

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