在太空自由遨翔
2023年5月14日
To Fly Free in Space
Image Credit: NASA, STS-41B
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. During Space Shuttle mission 41-B in 1984, McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an “untethered space walk“. The MMU worked 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 later replaced with the SAFER backpack propulsion unit.
Tomorrow’s picture: red eagle
说明: 在太空自由遨翔的滋味会是如何呢？漂浮在挑战者号航天飞机酬载舱上空100公尺处，遨翔在比前人更深入太空的麦坎德利斯，就有这种梦幻般的体验。借助于载人操控器（MMU），影像中的太空人麦坎德利斯得以自由漂浮在太空中。在1984年航天飞机的41-B任务期间，麦坎德利斯和美国宇航局的伙伴宇航员史都华，是首批体验“无系绳“太空行走的人类。载人操控器靠喷射氮气流来进行操控，而且常用于协助布署和回收卫星。载人操控器的质量高达140多公斤，因此在地球上非常沉重。然而和其他任何物体一样，一旦在轨道上，载人操控器是处在无重状态。载人操控器后来由简易背包式推进器（SAFER）所取代。
明日的图片: red eagle