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Astronauts experience weightlessness in the KC-135, 1978

In this photo from 1978, six astronauts who had been in training at the Johnson Space Center for almost a year are experiencing weightlessness. They are onboard the NASA KC-135, which uses a special parabolic pattern to create brief periods of microgravity, affording astronauts and astronaut candidates a preview of spaceflight. The photo should be viewed with feet at the top. The three astronauts in the foreground are (left to right): Richard O Covey, Steven R Nagal, and George D Nelson. In the center background is Robert L Stewart. Obscured in the background are Norman E Thagard and Ellison S Onizuka. (Source: NASA. Public domain.)