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Repairing Endeavour is too risky, says NASA

点击量:   时间:2018-02-11 03:02:04

By New Scientist Space and Reuters A small, deep gash in space shuttle Endeavour’s heat shield poses no threat to the ship and does not need repair, NASA said on Thursday after studying the problem for nearly a week. NASA officials considered sending astronauts out to patch the 8-centimetre (3-inch) gash in the shuttle’s belly, but decided Endeavour was all right and it was better not to interfere with the heat shield, mission management team chairman John Shannon said. “[The hole] does not constitute a risk to the crew, it is not expected to cause any damage to the vehicle structure,” he said in a briefing at Johnson Space Center in Houston, Texas, US. “You have something you know you can live with, why would you take the risk of the [spacewalk] to change that?” The gash occurred as Endeavour launched from Florida on 8 August when insulating foam and possibly ice from the fuel tank struck the shuttle’s underside, piercing its heat-resistant tiles. NASA worried that Endeavour could suffer further damage as a result of the breach during its fiery return to Earth. In the end, the agency decided that carrying out a repair would involve its own risks, Shannon said. It would have required two spacewalking astronauts to fill the hole with heat-resistant filler while they stood at the end of a robot arm in close proximity to the easily damaged tiles. Shannon said NASA performed exhaustive tests on mock-ups before officials reached a decision – which, he said, had not been unanimous. The agency has been cautious about heat shield damage since the shuttle Columbia broke apart shortly after re-entry in 2003, killing seven astronauts. The accident was blamed on damage to the wing heat shield caused during launch by foam that had fallen from the fuel tank. Even though no repair is needed, Endeavour astronauts will make the fourth spacewalk of their mission on Saturday, performing a list of chores on the International Space Station. Endeavour arrived at the station on 10 August and is due to undock on Monday and return to Florida on Wednesday. The space shuttle – Learn more in our continuously updated special report. More on these topics: