The shuttle Discovery is, at this moment, in orbit; Endeavour and Atlantis each has one more flight.

发现号航天飞机现在正在地球轨道上，奋进号和亚特兰蒂斯号还有一次飞行任务。

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The shuttles (Discovery, Atlantis and Endeavour) are being retired to make way for a new space plan aimed at sending astronauts to an asteroid by 2025 and ultimately onto Mars.

“发现号”“亚特兰蒂斯号”和“奋进号”航天飞机即将退休，为了让路于新的空间计划，后者的目标是2025年送宇航员到小行星上并最终登陆火星。

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Discovery heads to the Air and Space Museum's Udvar-Hazy Center in Virginia, Atlantis to Florida's Kennedy Space Center, and Endeavour to the California Science Center in Los Angeles.

“发现号”航天飞机将入住弗吉尼亚航空和航天博物馆Udvar-Hazy中心，“亚特兰蒂斯”航天飞机加盟佛罗里达州的肯尼迪航天中心，而“奋进号”则归洛杉矶的加州科学中心。

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Oh, how the times have changed... its final mission saw Atlantis successfully deliver the Russian Mini-Research Module Rassvet to the ISS. She'll be prepped one last time to stand-by as a rescue ship for the upcoming (and final) missions of Endeavor and Discovery, but Atlantis' days in space are likely over.

ENGADGET: Space Shuttle Atlantis ends its run of predicting disaster for other NASA shuttles

Endeavour, along with Discovery, Enterprise and Atlantis, became a museum piece after NASA ended its 30-year shuttle program in July 2011.

CNN: Space shuttle Endeavour's final touchdown

Well, if they get back to flying Atlantis and if they get back to flying Atlantis in September, which they dearly would like to do, they have to get the Discovery ready because the new rules say you have to have another shuttle ready to fly as a rescue mission.

NPR: Shuttle Landing Delayed Due to Poor Weather