NASA - National Aeronautics and Space Administration

 

An astronaut uses one of several specialty tools that will aid him in replacing Hubble’s gyroscopes. This photo was taken in the Neutral Buoyancy Laboratory at Johnson Space Center where the astronauts practice the servicing steps in a training pool that holds 6.2 million gallons of water. Diver-engineers from Goddard Space Flight Center observe and will modify tools and processes if necessary.

Credit: NASA