After an extra day in space,the crew of Discovery returned to Earth,landing at Edwards Air Force Base in California early on Tuesday morning.The shuttle and its crew spent two weeks in space,most of it aboard the International Space Station.It was the first flight of NASA's spaceshuttle fleet since February 2003,when the shuttle Columbia came apart while reentering Earth's atmosphere. NASA officials delayed Discovery's return for one day because of cloudy weather in Florida,where the shuttle was supposed to lanD. On Tuesday morning,mission controllers directed Discovery to a landing site in California,where the skies were clear.The crew members will have to wait until Wednesday to see their families when they all meet together in Houston at the Johnson Space Center. Discovery had a very busy mission in space,compared to past missions.The space shuttle docked with the International Space Station most of the journey,delivering badly needed supplies and repairing damaged parts.The crew spent a lot of time testing new repair techniques on their own shuttle,conducting three different spacewalks(where astronauts exit the space shuttle to do work outside).On the third spacewalk,astronaut Steve Robinson went underneath the shuttle to remove material sticking out from between the spacecraft's protective tiles. There were concerns in the last remaining days of Discovery's mission that a torn heat blanket—another shield against overheating in the space shuttle—may pose a problem to crew members. NASA officials and technicians worked on ways that the crew could fix the problem, but later decided it was not a risk. With the shuttle and its crew safely back on firm ground, NASA is hailing this mission, labeled STS114,as a huge success. “I hope this shows people that we're coming back,” NASA spaceflight chief Bill Readdy said after Discovery's successful landing. “We've got some more work to do. We know what we need to do and we'll do it. 小题1:Which of the following isn't included in the jobs of the shuttle Discovery?
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