Nasa unveils shuttle launch date	美国宇航局披露“发现”号航天飞机升空日期
The shuttle has been grounded for two-and-a-half years Nasa has set 13 July as the launch date for Discovery, the first shuttle to go into space since the Columbia disaster in February 2003. The announcement follows a two-day review of the Discovery's readiness for lift-off. An original launch date in May was put back because of ongoing redesign work on the shuttle's fuel tank. Columbia disintegrated after re-entering the Earth's atmosphere, killing all seven astronauts on board. Earlier this week, a panel monitoring Nasa said the agency had failed to meet three of 15 recommendations made by the Columbia Accident Investigation Board for the safe resumption of shuttle flights. But Nasa Administrator Michael Griffin said Discovery was fit for launch. "Based on a very thorough and very successful flight readiness review, we're currently 'go' for launch of Discovery on 13 July," he announced. An earlier investigation found Columbia broke up as a result of damage sustained when a chunk of fuel-tank insulating foam smashed into its left wing during lift-off two weeks earlier. The Caib probe concluded astronauts would still be unable to fix such damage once in orbit. While Nasa's focus was on how to prevent the insulating foam breaking off, concerns also emerged earlier this year about the build-up of ice on the outside of the fuel tank. The agency's management however decided the risk of ice striking the shuttle's heat shield was low enough to resume flights. Discovery will carry a seven-strong crew on a mission to take supplies and parts to the International Space Station. (Agencies)	美国宇航局（NASA）日前宣布将于7月13日发射“发现”号航天飞机。这将是美国航天飞机自2003年2月“哥伦比亚”号失事以来首次恢复发射。 之前，美国宇航局已对“发现”号的发射准备工作进行了为期两天的检查。 “发现”号原定于今年五月发射升空，但是由于当时正对飞船的油箱重新进行设计，而不得不推迟了发射日期。 “哥伦比亚”号航天飞机在返回地面途中，经过地球大气层时解体，导致机上七名宇航员全部遇难。 本周早些时候，一个美国宇航局监督小组声称，宇航局未能满足哥伦比亚事故调查委员会为恢复航天飞机安全飞行而提出的15条意见中的3条。 但是，美国宇航局局长迈克尔·格里芬却宣布，“发现”号已经做好了发射升空的准备。 他说：“我们对发射准备工作进行了非常全面且成功的评估，现决定在7月13日发射‘发现’号航天飞机。” 早先进行的调查发现，在“哥伦比亚”号航天飞机发射升空时，从外部燃料箱脫落的一块泡沫绝缘材料击中了航天飞机左翼，使其受损，从而导致了两周后“哥伦比亚”号在空中解体爆炸的悲剧。 哥伦比亚事故调查委员会经过周密调查后得出结论：万一航天飞机在轨道运行中发生类似的损坏，宇航员仍旧无法展开修复工作。 正当美国宇航局将工作重点放在如何防止泡沫绝缘材料脱落时，今年年初人们又开始担心燃料箱外侧集结的冰是否也会对航天飞机的飞行安全构成威胁。 然而，美国宇航局的管理层断然认为，这些冰块击中航天飞机防热护罩的风险极低，不会影响航天飞机的飞行。 “发现”号将把一个“身强力壮的”七人小组送入太空，给国际空间站带去补给和一些部件。 （中国日报网站译）