High Quality Content by WIKIPEDIA articles! STS-6 was a NASA Space Shuttle mission conducted using Space Shuttle Challenger, carrying the first Tracking and Data Relay Satellite, TDRS-1, into orbit. Launched on 4 April 1983, STS-6 was the sixth shuttle mission and the first of the ten missions flown by Challenger. The mission took off from Kennedy Space Center`s launch pad 39A, and landed at Edwards Air Force Base on 9 April. This was the first Space Shuttle mission during which a spacewalk was conducted, and the first in which the Extravehicular Mobility Unit (EMU) was used.