Space History Photo: Carr and Pogue in Skylab
Two astronauts humorously demonstrate zero-gravity during the 1974 Skylab 4 mission.
Credit: NASA

In this historical photo from the U.S. space agency, Astronaut Gerald P. Carr, Commander for the Skylab 4 mission, jokingly demonstrates weight training in zero-gravity as he balances astronaut William R. Pogue, pilot, upside down on his finger.

Each weekday, SPACE.com looks back at the history of spaceflight through photos (archive).