Space Shuttle Discovery (STS-31) lifts off Pad 39B while Columbia waits on Pad 39A, 0834 24 April 1990 Published on April 23, 2013 in 24 April 1990, 12:33:51 UTC, T minus ZeroFull resolution (1280 × 847) Next → Discovery (STS-31) lifts off Pad 39B with the Hubble Space Telescope. Sister ship Columbia waits on Pad 39A. (NASA)