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Weather delays shuttle landing attempt by a day

点击量:   时间:2017-06-12 05:02:12

By New Scientist Space, Reuters and AFP (Image: NASA TV) NASA on Thursday delayed for a day the landing of the space shuttle Atlantis because of bad weather in Florida. The agency ruled out the first landing opportunity in Florida, set for 1355 EDT (1755 GMT), because of thick cloud cover and rain. But continuing bad weather forced it to cancel the only other possible landing attempt on Thursday, scheduled for 1530 EDT (1930 GMT). The shuttle cannot land in rain because it has the potential to damage the thousands of ceramic tiles that protect the spaceships’s belly from the fiery heat of re-entry into the atmosphere. On Friday the shuttle will have two opportunities to land in Florida and, if the weather there continues to be bad, two more at Edwards Air Force Base in California, US. Friday’s first opportunity will be at Kennedy Space Center at 1418 EDT (1818 GMT), NASA managers say. Weather could still hamper the shuttle’s return home after its nearly two-week-long mission at the International Space Station, however. “We’re going to be fighting the same challenges at KSC (Kennedy Space Center), and at Edwards the winds are going to pick up,” astronaut Tony Antonelli at mission control in Houston told his colleagues aboard the shuttle. NASA wants to land Atlantis by Saturday as the shuttle only has enough fuel and supplies to stay in space until Sunday. Atlantis would have seven landing opportunities on Saturday, with two in Florida, two in California and three at the White Sands military base in New Mexico. NASA prefers to land the shuttle in Florida, as it costs nearly $2 million to return it to its launch base piggybacked atop a Boeing 747 – and such a trip would affect the schedule of future missions. Atlantis spent most of its 13-day mission at the International Space Station, where the crew installed a 16-tonne metal truss that included solar power panels to generate additional electricity for the half-finished $100 billion complex. NASA managers cleared Atlantis for landing after two inspections during flight and high-resolution photos taken by the space station crew found no damage to the orbiter’s heat shield. Heat shield problems are a major concern at NASA since the shuttle Columbia broke up while returning to Earth in 2003, killing the seven astronauts on board. The accident was blamed on an undetected crack in the heat shield. During one of four spacewalks performed by Atlantis crew members, astronaut John “Danny” Olivas patched up a torn thermal blanket that protects an area near the shuttle’s tail from heat. NASA engineers believe they underestimated how much heat the underlying shuttle layers had experienced during launch on 8 June. “When they modelled it, they made a mistake,” deputy shuttle programme manager John Shannon said of the original analysis. “Still, the engineering and safety teams believe there’s absolutely no risk at all during re-entry.” The Atlantis mission, which was delayed from March after the shuttle’s external fuel tank was damaged in a hailstorm in late February, was the first of four shuttle flights scheduled this year. The addition of the solar panels and other tasks performed by the shuttle crew prepared the space station, a project of 16 nations,