Today in outer space! February 7, 1984: First spacewalk.

McCandless carried a type of jetpack known as a crew maneuvering unit, or MMU. The MMU fitted on a regular EMU suit and included gas thrusters that allowed astronauts to travel much further from the space shuttle.

McCandless may have ventured 320 ft from the Challenger. The MMU was used on three space shuttle missions in 1984, and the astronauts used it to retrieve two broken communication satellites.