Space Shuttle Discovery (Orbiter Vehicle Designation: OV-103) is a retired American Space Shuttle orbiter. The spaceplane was one of the orbiters from NASA's Space Shuttle program and the third of five fully operational orbiters to be built.[2] Its first mission, STS-41-D, flew from August 30 to September 5, 1984. Over 27 years of service it launched and landed 39 times, aggregating more spaceflights than any other spacecraft as of December 2024[update].[3] The Space Shuttle launch vehicle had three main components: the Space Shuttle orbiter, a single-use central fuel tank, and two reusable solid rocket boosters. Nearly 25,000 heat-resistant tiles cover the orbiter to protect it from high temperatures on re-entry.[4]
Discovery became the third operational orbiter to enter service, preceded by Columbia and Challenger.[5] After the Challenger and Columbia accidents, Discovery became the oldest surviving orbiter. It embarked on its final mission, STS-133, on February 24, 2011, and touched down for the last time at Kennedy Space Center on March 9,[6] having spent a cumulative total of nearly a full year in space. Discovery performed both research and International Space Station (ISS) assembly missions, and also carried the Hubble Space Telescope into orbit among other satellites.
Space Shuttle Discovery launched the Hubble Space Telescope and conducted the second and third Hubble service missions. It also launched the Ulysses probe and three TDRS satellites. Twice Discovery was chosen as the "Return To Flight" Orbiter, first in 1988 after the loss of Challenger in 1986, and then again for the twin "Return To Flight" missions in July 2005 and July 2006 after the Columbia disaster in 2003. Project Mercury astronaut John Glenn, who was 77 at the time, flew with Discovery on STS-95 in 1998, making him the oldest person to go into space at that time in history.[10]
During its construction, Discovery was fitted with several black tiles near the middle starboard window where there should have been white tiles. It is unknown if this was the result of a harmless manufacturing mishap or done intentionally to give a distinctive look to the shuttle. This feature has been called 'teardrop' and allowed Discovery to be told apart from the rest of the fleet without looking at its name, although often unnoticed by the uninitiated.[14]
The spacecraft weighed roughly 6,870 lb (3,120 kg) less than Columbia when it was brought into service due to optimalizations determined during the construction and testing of Enterprise, Columbia and Challenger.[10]Discovery weighs 6 pounds (2.7 kg) heavier than Atlantis and 363 pounds (165 kg) heavier than Endeavour after further weight-saving adjustments were made.[15]
Part of the Discovery weight optimizations included the greater use of quilted AFRSI blankets rather than the white LRSI tiles on the fuselage, and the use of graphite epoxy instead of aluminum for the payload bay doors and some of the wing spars and beams.[16]
Upon its delivery to the Kennedy Space Center in 1983, Discovery was modified alongside Challenger to accommodate the liquid-fueled Centaur-G booster, which had been planned for use beginning in 1986 but was cancelled in the wake of the Challenger disaster.[17]
Beginning in late 1995, the orbiter underwent a nine-month Orbiter Maintenance Down Period (OMDP) in Palmdale, California. This included outfitting the vehicle with a 5th set of cryogenic tanks and an external airlock to support missions to the International Space Station. As with all the orbiters, it could be attached to the top of specialized aircraft and did so in June 1996 when it returned to the Kennedy Space Center, and later in April 2012 when sent to the Udvar-Hazy Center, riding piggy-back on a modified Boeing 747.[10]
After STS-105, Discovery became the first of the orbiter fleet to undergo Orbiter Major Modification (OMM) period at the Kennedy Space Center. Work began in September 2002 to prepare the vehicle for Return to Flight. The work included scheduled upgrades and additional safety modifications.[10]
SCA N905NA carrying Discovery on the last flyover of the National Mall at around 10:15 am EDT, during its 11:05 am landing at Dulles airport on April 17, 2012[18]
Enterprise and Discovery exchanged and Discovery on display at the National Air and Space Museum, Steven F. Udvar-Hazy Center
Flights
By its last mission, Discovery had flown 149 million mi (240 million km) in 39 missions, completed 5,830 orbits, and spent 365 days in orbit over 27 years.[30]Discovery flew more flights than any other Orbiter Shuttle, including four in 1985 alone. Discovery flew both "return to flight" missions after the Challenger and Columbia disasters: STS-26 in 1988, STS-114 in 2005, and STS-121 in 2006. Discovery flew the ante-penultimate mission of the Space Shuttle program, STS-133, having launched on February 24, 2011. Endeavour flew STS-134 and Atlantis performed STS-135, NASA's last Space Shuttle mission. On February 24, 2011, Space Shuttle Discovery launched from Kennedy Space Center's Launch Complex 39-A to begin its final orbital flight.[31]
SPACEHAB, second flight of John Glenn, who was 77 years of age at that time, the oldest man in space and third incumbent member of Congress to enter space. Pedro Duque became the first Spaniard in space.
Second "Return To Flight" mission since the Space Shuttle Columbia disaster, owing to concerns surrounding foam debris from the external tank during STS-114; International Space Station (ISS) supplies delivery, test new safety and repair techniques.
ISS crew rotation and assembly (carries and assembles the P5 truss segment); Last flight to launch on pad 39-B; First night launch since Space Shuttle Columbia disaster.
International Space Station crew rotation and assembly of a fourth starboard truss segment (ITS S6) and a fourth set of solar arrays and batteries. Also replaced a failed unit for a system that converts urine to drinking water.
ISS resupply using the Leonardo Multi-Purpose Logistics Module. The mission also marked the first time that four women were in space and the first time that two Japanese astronauts were together on a space station.[32] Longest mission for this Orbiter.
The Flow Director was responsible for the overall preparation of the shuttle for launch and processing it after landing, and remained permanently assigned to head the spacecraft's ground crew while the astronaut flight crews changed for every mission. Each shuttle's Flow Director was supported by a Vehicle Manager for the same spacecraft. Space Shuttle Discovery's Flow Directors were:
Until 01/1991: John J. "Tip" Talone Jr. (afterwards Flow Director for Endeavour)[34]
^"Part II. Discovery (OV-103)"(PDF). Space Transportation System Haer No. TX-116. NASA.gov. Archived(PDF) from the original on October 22, 2020. Retrieved February 28, 2015.
^"STS-41D Press Kit"(PDF). NASA. August 1984. p. 13. Archived from the original(PDF) on March 15, 2013. Retrieved July 12, 2013. Graphite epoxy has replaced some internal aluminum spars and beams in the wings and in the payload bay doors.
^Lardas, Mark (2012). Space Shuttle Launch System: 1972–2004. Osprey Publishing. p. 37.
^Berger, Eric (December 7, 2009). "Discovery is Smithsonian's". Houston Chronicle. Archived from the original on January 3, 2010. Retrieved January 3, 2010.