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 Discovery deploys the Hubble Space Telescope. | |
| Names | Space Transportation System-31 STS-31R |
|---|---|
| Mission type | Hubble Space Telescope deployment |
| Operator | NASA |
| COSPAR ID | 1990-037A |
| SATCAT no. | 20579 |
| Mission duration | 5 days, 1 hour, 16 minutes, 6 seconds |
| Distance travelled | 3,328,466 km (2,068,213 mi) |
| Orbits completed | 80 |
| Spacecraft properties | |
| Spacecraft | Space Shuttle Discovery |
| Launch mass | 117,586 kg (259,233 lb) |
| Landing mass | 85,947 kg (189,481 lb) |
| Payload mass | 11,878 kg (26,187 lb) |
| Crew | |
| Crew size | 5 |
| Members | |
| Start of mission | |
| Launch date | April 24, 1990, 12:33:51 UTC (8:33:51 am EDT) |
| Launch site | Kennedy, LC-39B |
| Contractor | Rockwell International |
| End of mission | |
| Landing date | April 29, 1990, 13:49:57 UTC (6:49:57 am PDT) |
| Landing site | Edwards, Runway 22 |
| Orbital parameters | |
| Reference system | Geocentric orbit |
| Regime | Low Earth orbit |
| Perigee altitude | 613 km (381 mi) |
| Apogee altitude | 615 km (382 mi) |
| Inclination | 28.45° |
| Period | 96.70 minutes |
| Instruments | |
| |
 STS-31 mission patch  From left: Bolden, Hawley, Shriver, McCandless and Sullivan Hubble Space Telescope missions | |
STS-31 was the 35th mission of NASA's Space Shuttle program and the tenth flight of the Space Shuttle Discovery. The primary purpose of this mission was the deployment of the Hubble Space Telescope (HST) into low Earth orbit. Discovery lifted off from Launch Complex 39B on April 24, 1990, from Kennedy Space Center, Florida.
Following the Challenger accident clarification was required on mission numbering. As STS-51-L was also designated STS-33, future flights with the previous STS-26 through STS-33 designators would require the R in their documentation to avoid conflicts in tracking data from one mission to another.[citation needed]
Discovery's crew deployed the Hubble Space Telescope on April 25, 1990, and then spent the rest of the mission tending to various scientific experiments in the Shuttle's payload bay as well as operating a set of IMAX cameras to record the mission. Discovery's launch marked the first time since January 1986 that two Space Shuttles had been on the launch pad at the same time – Discovery on 39B and Columbia on 39A.