Hubble Simulator
The Vehicle Electrical System Test facility combines an exact duplicate of the Hubble Space Telescope's electrical system, which was designed in the 1980s, with simulators that mimic other components ― such as the batteries, solar arrays, pointing control, and instruments ― to create a full replica of Hubble. On June 11, 2019, the Hubble team used this simulator to test upgraded flight software that was later uploaded to the actual spacecraft. Seen here is Ron Stattel, flight software engineer, attempting to diagnose equipment that will not properly start-up. A clock in the foreground shows the day of the year, hour, minutes and seconds.
Credits: NASA Goddard / R. Roth