In 1965, Ed White became the first American to perform a spacewalk when he stepped out of the Gemini IV capsule and floated in space for about 20 minutes. He liked it so much, he said, that returning to the capsule was “the saddest moment of my life.” White had been beaten to the first spacewalk ever by cosmonaut Alexei Leonov several months earlier. But the American had the advantage of having a way to maneuver himself in space, thanks to a compressed-air gun. More sophisticated personal space-propulsion systems were already in the works.
The Bendix Corp. developed a mockup of this modular EVA work platform [PDF] in 1969. (It’s worth downloading that PDF just for the awesome da Vinci-esque half-human/half-robot logo on the cover page.) Strapped into the platform, an astronaut could perform missions that required a little over 2 kilometers in range and then, using electrically heated epoxy adhesive pads, anchor the unit to a space station, satellite, or other off-world worksite. The pads were not reusable; at undocking, they would be left behind, still stuck to the work surface. Based on concepts developed at Johns Hopkins University’s Applied Physics Laboratory, the platform was intended to provide astronauts with “a relatively safe and non-taxing method of accomplishing many EVA [extravehicular activity] tasks planned for advanced missions, including inspection, servicing, construction and assembly, repair, and cargo transfer.”
While NASA decided not to deploy work platforms like this in the 1970s, many similar capabilities ended up in the Manned Maneuvering Unit (MMU), an untethered backpack propulsion device that was first flight-tested as part of the space shuttle’s STS-41B mission in February 1984. The MMU allowed astronauts to perform satellite retrieval, science investigations and observations, in-space construction, and rescue operations, and it was used successfully on three missions. However, after the Challenger disaster in 1986, NASA decided that it was safer (and easier) to just fly right up to things and grab them with the Canadarm, Canada’s robotic contribution to the space shuttle. Flown MMUs are now on display at the Smithsonian and the Kennedy Space Center.
These days, NASA space suits are equipped with a scaled-down version of the MMU called SAFER (for Simplified Aid For EVA Rescue). It’s basically a small propulsive backpack for use in emergencies, providing just enough thrust for astronauts to return to safety if a tether breaks. NASA is working on a way to control the SAFER system remotely, to bring back an astronaut who’s incapacitated or who, like White, just thinks spacewalks are fun and doesn’t want to come back inside.
Part of a continuing series looking at old photographs that embrace the boundless potential of technology, with unintentionally hilarious effect.