银河说-每日一图171731期：在太空中自由遨翔

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在太空中自由遨翔

在太空中自由遨翔的滋味会是如何呢？漂浮在挑战者号太空飞船船舱上空100公尺外，遨翔在比前人更深入太空的麦凯德利斯，就有过这种梦幻般的体验。在载人操控器(MMU)的协助下，拍下来宇航员麦凯德利斯自由漂浮在太空中的画面。在1984年执行航天飞机41-B任务期间，麦凯德利斯和他的小伙伴美国国家航空航天局的宇航员史都华，是首批实验”无系绳”太空漫步的人类。载人操控器通过喷射氮气流來进行操控，并且常用于协助卫星的部署和回收。虽然载人操控器的重量超过140公斤，在地面上显得非常沉重，但和其他任何事物一样，一旦在轨道上，载人操控器就是处在失重状态。但是如今，载人操控器已被更安全的背包推进装置(SAFER)取代。

译：银河说翻译组 雪洋洋

To Fly Free in Space
Image Credit: STS-41B, NASA

Explanation: What would it be like to fly free in space? At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was living the dream — floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space.McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an “untethered space walk” during Space Shuttle mission 41-B in 1984. The MMUworked by shooting jets of nitrogen and was used to help deploy and retrieve satellites. With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is weightless when drifting in orbit. The MMU was replaced with the SAFER backpack propulsion unit.

自由翱翔。

有如此体验不枉此生啊！