Artist-supplied caption:
This patch celebrates the 6 Orbiters in the Shuttle fleet, the total number of missions launch by the US. The center shows the Shuttle mission cycle (launch, flight and recovery). The US flag denotes the great achievement of the United States in developing the Space Shuttle. The off geometric shape in behind the Shuttle cycle is meant to convey the repeating nature of Shuttle operations (a wheel turning or a bolt being turned).
