STS-51-F was a space shuttle mission that was launched on July 29, 1985. The mission was flown by the space shuttle Challenger and was the 19th mission in the Space Transportation System (STS) program. The primary objectives of the mission were to deploy the Palapa B-2 and the Westar 6 communications satellites, and to perform various scientific experiments in the Spacelab module. The mission patch for STS-51-F features the space shuttle Challenger, which is surrounded by a blue circle representing the Earth. The patch also features the words “STS-51-F” and “Challenger,” as well as the mission’s primary payloads, the Palapa B-2 and the Westar 6 satellites. The patch also includes the insignias of NASA and the Spacelab program.