Astronauts to Check Damage to Shuttle

Astronauts aboard the shuttle Endeavor will today scrutinize a 3in-square gouge in the spacecraft's heat shield to determine if inflight repairs are needed.

Video footage showed a chunk of ice striking the shuttle's underside 58 seconds after last Wednesday's launch from Florida, provoking memories of the 2003 Columbia disaster.

Nasa officials admitted they were concerned by the damage to Endeavor, which will be studied today using a high-resolution camera and laser mounted on the shuttle's 49ft robotic arm. Depending on their findings, astronauts have three possible ways of repairing the shield: heat-resistant paint, fast-setting space putty, or a thermal plate.

'We have a rich history of tile damage, some of which was more significant looking than what we have here,' said John Shannon, chairman of the mission management team.

Shuttles on almost all of the 119 previous missions have returned safely with some degree of tile damage, or in some cases with tiles missing altogether. But since the Columbia tragedy, in which seven astronauts were killed when the orbiter blew up on re-entry to Earth's atmosphere, Nasa has ordered a detailed examination of every shuttle before giving the all clear for return.

Meanwhile, in another worrying development, engineers are looking at how Endeavor came within a mile of a collision with the remnants of a 30-year-old rocket, during its journey to the International Space Station.