The Space Shuttle Challenger, atop a mobile launch platform, slowly moves through the Florida fog to Launch Pad 39A in preparation for its first liftoff on the STS-6 mission. The fully assembled Shuttle, weighting 12,000 pounds less than predecessor Columbia, completed the trip to the pad in just over six hours on November 30, 1982. STS-6 was the sixth NASA Space Shuttle mission and the maiden flight of the Space Shuttle Challenger. Launched from Kennedy Space Center on April 4,1983, the mission deployed the first Tracking and Data Relay Satellite, TDRS-1, into orbit, before landing at Edwards Air Force Base on April 9. STS-6 was the first Space Shuttle mission during which a spacewalk was conducted, and hence was the first in which the Extravehicular Mobility Unit (EMU) was used.