Wilde Richard C, McBarron James W, Manatt Scott A, McMann Harold J, Fullerton Richard K
Acta Astronaut. 2002 Jul-Nov;51(1-9):579-90. doi: 10.1016/s0094-5765(02)00096-6.
In the 36 years between June 1965 and February 2001, the US human space flight program has conducted 100 spacewalks, or extravehicular activities (EVAs), as NASA officially calls them. EVA occurs when astronauts wearing spacesuits travel outside their protective spacecraft to perform tasks in the space vacuum environment. US EVA started with pioneering feasibility tests during the Gemini Program. The Apollo Program required sending astronauts to the moon and performing EVA to explore the lunar surface. EVA supported scientific mission objectives of the Skylab program, but may be best remembered for repairing launch damage to the vehicle and thus saving the program. EVA capability on Shuttle was initially planned to be a kit that could be flown at will, and was primarily intended for coping with vehicle return emergencies. The Skylab emergency and the pivotal role of EVA in salvaging that program quickly promoted Shuttle EVA to an essential element for achieving mission objectives, including retrieving satellites and developing techniques to assemble and maintain the International Space Station (ISS). Now, EVA is supporting assembly of ISS. This paper highlights development of US EVA capability within the context of the overarching mission objectives of the US human space flight program.
在1965年6月至2001年2月的36年间，美国载人航天计划进行了100次太空行走，即美国国家航空航天局（NASA）官方所称的舱外活动（EVA）。当身着太空服的宇航员在其防护航天器之外的太空真空环境中执行任务时，就会发生舱外活动。美国的舱外活动始于双子座计划期间的开创性可行性测试。阿波罗计划要求将宇航员送上月球并进行舱外活动以探索月球表面。舱外活动支持了天空实验室计划的科学任务目标，但或许因其修复了航天器的发射损伤从而挽救了该计划而最为人铭记。航天飞机的舱外活动能力最初计划为一套可随意搭载飞行的装备包，主要用于应对航天器返回时的紧急情况。天空实验室的紧急情况以及舱外活动在挽救该计划中所起的关键作用，迅速将航天飞机的舱外活动提升为实现任务目标的一个基本要素，这些目标包括回收卫星以及研发用于组装和维护国际空间站（ISS）的技术。如今，舱外活动正在为国际空间站的组装提供支持。本文在美国载人航天计划总体任务目标的背景下，着重介绍了美国舱外活动能力的发展情况。
