View of a single engine orbital maneuvering system (OMS) firing on the Discovery. The payload bay is open and the protective canisters for the AUSSAT communications satellite (open) and the ASC-1 are visible. A cloudy Earth's horizon can be seen above the orbiter.

DISCOVERY ORBITER ONBOARD ACTIVITIES PAYLOAD BAY TEST FIRING ORBIT MANEUVERING ENGINE SPACE SHUTTLE SPACE SHUTTLE MISSION 51-I

View of the firing of a single engine OMS