【摘 要】
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Astronauts are not the only ones who dream of going into space. Since the earliest days of human spaceflight, many other people have also longed to view Earth a
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Astronauts are not the only ones who dream of going into space. Since the earliest days of human spaceflight, many other people have also longed to view Earth and the heavens from above the atmosphere.rnIn 2018, Virgin Galactic, a private—soon to be public [1]—spaceflight company headed by billionaire Richard Branson, has brought that vision closer to reality than ever before.
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