STS-31

STS-31

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 (achieved)
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	Loren Shriver Charles Bolden Bruce McCandless II Steven Hawley Kathryn D. Sullivan
Start of mission
Launch date	April 24, 1990, 12:33:51 UTC
Rocket	Space Shuttle Discovery
Launch site	Kennedy Space Center, LC-39B
Contractor	Rockwell International
End of mission
Landing date	April 29, 1990, 13:49:57 UTC
Landing site	Edwards Air Force Base, 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
Air Force Maui Optical Site (AMOS) Ascent Particle Monitor (APM) IMAX Cargo Bay Camera (ICBC) In-flight Radiation Dose Distribution (IDRD) Protein Crystal Growth (PCG) Radiation Monitoring Equipment III (RME III)
STS-31 mission patch Charles Bolden, Steven Hawley, Loren Shriver, Bruce McCandless II, Kathryn D. Sullivan Space Shuttle program ← STS-36 (34) STS-41 (36) →

STS-31 was the 35th mission of NASA's Space Shuttle program. The primary purpose of this mission was the deployment of the Hubble Space Telescope (HST) into low Earth orbit. The mission used the Space Shuttle Discovery (the tenth mission for this orbiter), which 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.