On This Day in Space: First Untethered Spacewalk by NASA Astronaut 🚀

On February 7, 1984, NASA astronaut Bruce McCandless became the first person to go on a spacewalk without a tether.

McCandless was wearing a type of jetpack known as the Manned Maneuvering Unit, or MMU. The MMU fit over a regular EMU spacesuit and included gas thrusters that allowed astronauts to venture much farther away from the space shuttle. McCandless was able to venture 320 feet away from the space shuttle Challenger. The MMU was used during three space shuttle missions in 1984, and astronauts used it to retrieve two faulty communications satellites.