Manned Maneuvering Unit (MMU): untethered spacewalk
Unidad de maniobra tripulada (MMU): paseo espacial sin cable
- Date
- 7 de febrero de 1984 · confidence high
- Place
- Kennedy Space Center, Florida, United States
- Credited to
- NASA and Martin Marietta (Bruce McCandless, Robert Stewart)
- Field
- Movement
What it is
A nitrogen-propelled backpack that let McCandless move more than 90 m from the Space Shuttle Challenger without any tether. It was the first free flight of an astronaut in orbit.
It was withdrawn from use after 1984 because of cost and risk following the Challenger accident (1986). A much smaller emergency version, SAFER, remains on the ISS.
What it led to
- satellite rescue and repair (Solar Max, Palapa B2 and Westar 6)
- SAFER, the emergency version used on the ISS
- extravehicular procedures with autonomous manoeuvring