Fly Free in Space

Fly Free in Space - At about 1/2 a mile from the cargo bay of the space shuttle, Bruce McCandless II was farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), this astronaut was floating free in space. The MMU works by shooting jets of nitrogen and has since been used to help deploy and retrieve satellites. — at lmage Credit: STS-41B/NASA.