Editing Marshall Space Flight Center (section)

===1980s and 1990s – early Shuttle era===
The [[Space Shuttle]] was the most complex spacecraft ever built. From the start of the Shuttle program in 1972, the management and development of Space Shuttle propulsion was a major activity at MSFC. [[Alex McCool|Alex A. McCool, Jr.]] was the first manager of MSFC's Space Shuttle Projects Office.{{citation_needed|date=July 2019}}

Throughout 1980, engineers at MSFC participated in tests related to plans to launch the first Space Shuttle. During these early tests and prior to each later Shuttle launch, personnel in the Huntsville Operations Support Center monitored consoles to evaluate and help solve any problems at the Florida launch that might involve Shuttle propulsion.{{citation_needed|date=July 2019}}

On April 12, 1981, [[Space Shuttle Columbia|''Columbia'']] made the first orbital test flight with a crew of two astronauts. This was designated [[STS-1]] (Space Transportation System-1) and verified the combined performance of the entire system. STS-1 was followed by [[STS-2]] on November 12, demonstrating safe re-launch of ''Columbia''. During 1982, [[STS-3]] and [[STS-4]] were completed. [[STS-5]], launched November 11, was the first operational mission; carrying four astronauts, two commercial satellite were deployed. In all three of these flights, on-board experiments were carried and conducted on pallets in the Shuttle's cargo bay.{{citation_needed|date=August 2019}}

Space Shuttle [[Space Shuttle Challenger|''Challenger'']] was launched on mission [[STS-51-L]] on 28 January 1986, resulting in the [[Space Shuttle Challenger disaster|Space Shuttle ''Challenger'' disaster]] one minute and thirteen seconds into the flight. Subsequent analysis of the high-speed tracking films and telemetry signals showed that a leak occurred in a joint on one of the [[Space Shuttle Solid Rocket Booster|solid rocket boosters (SRBs)]]. The escaping flame impinged on the surface of the [[Space Shuttle external tank|external tank (ET)]], resulting in the destruction of the vehicle and loss of the crew. The basic cause of the disaster was determined to be an [[O-ring]] failure in the right SRB; cold weather was a contributing factor. A redesign and extensive testing of the SRBs was conducted. There were no Space Shuttle missions in the remainder of 1986 or in 1987. Flights resumed in September 1988 with [[STS-26]].{{citation_needed|date=July 2019}}

====Shuttle missions and payloads====
The Space Shuttles carried a wide variety of payloads, from scientific research equipment to highly classified military satellites. The flights were assigned a Space Transportation System (STS) number, in general sequenced by the planned launch date. The [[list of space shuttle missions]] shows all flights, their missions, and other information.{{citation_needed|date=July 2019}}

MSFC managed the adaptation of the [[Inertial Upper Stage]]. This solid rocket was first flown in May 1989, propelling the ''[[Magellan (spacecraft)|Magellan]]'' planetary spacecraft from Orbiter ''Atlantis'' on a 15-month loop around the Sun and eventually into orbit around Venus for four years of radar surface-mapping.{{citation_needed|date=July 2019}}

Many Shuttle flights carried equipment for performing on-board research. Such equipment was accommodated in two forms: on pallets or other arrangements in the Shuttle's cargo bay (most often in addition to hardware for the primary mission). The integration of these experimental payloads was the responsibility of MSFC.{{citation_needed|date=July 2019}}

Pallet experiments were of a variety of types and complexity, including fluid physics, materials science, biotechnology, combustion science, and commercial space processing. For some missions, an aluminum bridge fitting across the cargo bay was used. This could carry 12 standard canisters holding isolated experiments, particularly those under the [[Getaway Special]] (GAS) program. GAS flights were made available at low cost to colleges, universities, US companies, individuals, foreign governments, and others.{{citation_needed|date=July 2019}}

On some flights, a variety of pallet experiments constituted the full payload, with examples including [[STS-35|Astronomy Laboratory-1]] (ASTRO-1) and [[STS-45|Atmospheric Laboratory for Applications and Science]] (ATLAS 1).{{citation_needed|date=July 2019}}

====Spacelab====
In addition to the pallet experiments flown on the Space Shuttle, many other experiments were performed onboard [[Spacelab]]. This was a reusable laboratory consisting of multiple components, including a pressurized module, an unpressurized carrier, and other related hardware. Under a program overseen by MSFC, ten Europeans nations jointly designed, built, and financed the first Spacelab through the European Space Research Organisation ([[ESRO]]. In addition, Japan funded a Spacelab for STS-47, a dedicated mission.<ref>Lord, Douglas R.; [https://archive.org/details/nasa_techdoc_19880009991 "Spacelab: An international success story"] NASA, Jan. 1, 1987</ref>

Over a 15-year period, Spacelab components flew on 22 shuttle missions, the last in April 1998. Examples of Spacelab missions follow:{{citation_needed|date=July 2019}}

*[[STS-9|Spacelab 1]] was flown on STS-9, launched November 28, 1983. A Shuttle ''Columbia'' flight, this was the first with six astronauts, including two Payload Specialists from the ESRO. There were 73 experiments carried out in astronomy and physics, atmospheric physics, Earth observations, life sciences, materials sciences, and space plasma physics.{{citation_needed|date=July 2019}}
*[[STS-50|U.S. Microgravity Laboratory 1]] (USML-1) was launched in June 1992 on STS-50, the first [[Extended Duration Orbiter]]. During 14 days, 31 microgravity experiments were completed in round-the-clock operations. [[STS-73|USML-2]] was launched in October 1995 on STS-73 with an MSFC scientist, [[Frederick W. Leslie]], as an on-board Payload Specialist.{{citation_needed|date=July 2019}}

In early 1990, MSFC's Spacelab Mission Operations Control Center was formed to control all Spacelab missions, replacing the Payload Operations Control Center formerly situated at the JSC from which previous Spacelab missions were operated.{{citation_needed|date=August 2019}}

====International Space Station====
NASA began planning to build a space station in 1984, named ''Freedom'' in 1988. By the early 1990s, planning for four different stations were underway: the American ''Freedom'', the Soviet/Russian ''[[Mir-2]]'', the European ''Columbus'', and the Japanese ''[[Japanese Experimental Module|Kibō]]''. In November 1993, plans for ''Freedom'', ''Mir-2'', and the European and Japanese modules were incorporated into a single [[International Space Station]] (ISS).{{citation_needed|date=July 2019}} The ISS is composed of modules assembled in orbit, starting with the Russian module [[Zarya (ISS module)|''Zarya'']] in November 1998. This was followed in December by the first U.S. module, ''Unity'' also called Node 1, built by Boeing in facilities at MSFC.<ref>{{cite web |url=http://www.boeing.com/defense-space/space/spacestation/docs/ISS_overview.pdf |title=Boeing: International Space Station |website=www.boeing.com |access-date=22 March 2018 |archive-date=13 October 2012 |archive-url=https://web.archive.org/web/20121013222948/http://www.boeing.com/defense-space/space/spacestation/docs/ISS_overview.pdf |url-status=live }}</ref>

ISS assembly continued throughout the next decade, with continuously occupancy since February 7, 2001. Since 1998, 18 major U.S. components on the ISS have been assembled in space. In October 2007, [[Harmony (ISS module)|''Harmony'']] or Node 2, was attached to ''Destiny''; also managed by MSFC, this gave connection hubs for European and Japanese modules as well as additional living space, allowing the ISS crew to increase to six. The 18th and final major U.S. and Boeing-built element, the Starboard 6 Truss Segment, was delivered to the ISS in February 2009. With this, the full set of solar arrays could be activated, increasing the power available for science projects to 30&nbsp;kW. That marked the completion of the [[United States Orbital Segment]] (USOS) of the station.{{citation_needed|date=July 2019}} On 5 March 2010, Boeing officially turned over the USOS to NASA.<ref>{{Cite web |url=http://boeing.mediaroom.com/2010-03-05-Boeing-Transfers-US-Portions-of-International-Space-Station-to-NASA |title=Boeing Transfers US Portions of International Space Station to NASA |date=5 March 2010 |website=Boeing |access-date=18 August 2017 |archive-date=19 August 2017 |archive-url=https://web.archive.org/web/20170819062816/http://boeing.mediaroom.com/2010-03-05-Boeing-Transfers-US-Portions-of-International-Space-Station-to-NASA |url-status=live }}</ref>

====Hubble Space Telescope====
In 1962, the first [[Orbiting Solar Observatory]] was launched, followed by the [[Orbiting Astronomical Observatory]] (OAO) that carried out ultraviolet observations of stars between 1968 and 1972. These showed the value of space-based astronomy, and led to the planning of the Large Space Telescope (LST) that would be launched and maintained from the forthcoming space shuttle. Budget limitations almost killed the LST, but the astronomy community – especially [[Lyman Spitzer]] – and the National Science Foundation pressed for a major program in this area. Congress finally funded LST in 1978, with an intended launch date of 1983.{{citation_needed|date=July 2019}}

MSFC was given responsibility for the design, development, and construction of the telescope, while [[Goddard Space Flight Center]] (GFC) was to develop the scientific instruments and ground-control center. The project scientist was C. Robert O’Dell, then chairman of the Astronomy Department at the [[University of Chicago]]. The telescope assembly was designed as a [[Cassegrain reflector]] with hyperbolic mirror polished to be [[diffraction limited]]; the primary mirror had a diameter of {{cvt|2.4|m|in}}. The mirrors were developed by the optics firm Perkin-Elmer. MSFC could not test the performance of the mirror assembly until the telescope was launched and placed in service.<ref>Zimmerman, Robert; ''The Universe in a Mirror: The Saga of the Hubble Space Telescope and Visionaries Who Built It''; Princeton Univ. Press, 2008</ref>

The LST was named the [[Hubble Space Telescope]] in 1983, the original launch date. There were many problems, delays, and cost increases in the program, and the ''Challenger'' disaster delayed the availability of the launch vehicle. The [[Hubble Space Telescope]] was launched in April 1990, but gave flawed images due to a flawed primary mirror that had [[spherical aberration]]. The defect was found when the telescope was in orbit. Fortunately, the Hubble telescope had been designed to allow in-space maintenance, and in December 1993, mission STS-61 carried astronauts to the Hubble to make corrections and change some components. A second repair mission, STS-82, was made in February 1997, and a third, STS-103, in December 1999. Another servicing mission (STS-109) was flown on 1 March 2002. For these repair missions, the astronauts practiced the work in MSFC's Neutral Buoyancy Facility, simulating the weightless environment of space.{{citation_needed|date=July 2019}}

Based on the success of earlier maintenance missions, NASA decided to have a fifth service mission to Hubble; this was STS-125 flown on May 11, 2009. The maintenance and addition of equipment resulted in Hubble performance considerably better than planned at its origin. It is now expected that the Hubble will remain operational until its successor, the [[James Webb Space Telescope]] (JWST), is available in 2018.{{update inline|date=July 2019}}<ref>{{cite web |url=http://www.jwst.nasa.gov/about.html |archive-url=https://web.archive.org/web/20060601114627/http://www.jwst.nasa.gov/about.html |url-status=dead |archive-date=1 June 2006 |title=About Webb/NASA |website=www.jwst.nasa.gov |access-date=22 March 2018}}</ref><ref>{{cite web |url=http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts125/main/overview.html |title=NASA - STS-125: The Final Visit |first=Jerry Wright |last=JSC |website=www.nasa.gov |access-date=22 March 2018 |archive-date=7 May 2017 |archive-url=https://web.archive.org/web/20170507202807/https://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts125/main/overview.html |url-status=live }}</ref>

====Chandra X-Ray Observatory====
Even before HEAO-2 (the [[Einstein Observatory]]) was launched in 1978, MSFC began preliminary studies for a larger X-ray telescope. To support this effort, in 1976 an X-Ray Test Facility, the only one of its size, was constructed at MSFC for verification testing and calibration of X-ray mirrors, telescope systems, and instruments. With the success of HEAO-2, MSFC was given responsibility for the design, development, and construction of what was then known as the Advanced X-ray Astrophysics Facility (AXAF). The [[Smithsonian Astrophysical Observatory]] (SAO) partners with MSFC, providing the science and operational management.<ref>{{cite web |title=The Chandra X-ray Center |date=September 3, 2019 |url=https://chandra.harvard.edu/about/asc.html |website=harvard.edu |access-date=June 7, 2023 |archive-date=May 30, 2023 |archive-url=https://web.archive.org/web/20230530085345/https://www.chandra.harvard.edu/about/asc.html |url-status=live }}</ref>

Work on the AXAF continued through the 1980s. A major review was held in 1992, resulting in many changes; four of the twelve planned mirrors were eliminated, as were two of the six scientific instruments. The planned circular orbit was changed to an elliptical one, reaching one-third of the way to the Moon at its farthest point; this eliminated the possibility of improvement or repair using the Space Shuttle, but it placed the spacecraft above the Earth's radiation belts for most of its orbit.{{citation_needed|date=July 2019}}

AXAF was renamed [[Chandra X-ray Observatory]] in 1998. It was launched July 23, 1999, by the Shuttle ''Columbia'' (STS-93). An [[Inertial Upper Stage]] booster adapted by MSFC was used to transport ''Chandra'' to its high orbit Weighing about {{cvt|22,700|kg|lb}}, this was the heaviest payload ever launched by a Shuttle. Operationally managed by the SAO, ‘’Chandra’’ has been returning excellent data since being activated. It initially had an expected life of five years, but this has now been extended to 15 years or longer.<ref>[http://www.nasa.gov/mission_pages/chandra/main/index.html "Chandra: Exploring the Invisible Universe"] {{Webarchive|url=https://web.archive.org/web/20110226183619/http://www.nasa.gov/mission_pages/chandra/main/index.html |date=2011-02-26 }} MSFC</ref>

The [[Chandra X-ray Observatory]], originating at MSFC, was launched on July 3, 1999, and is operated by the [[Smithsonian Astrophysical Observatory]]. With an [[angular resolution]] of 0.5 [[arcsecond]] (2.4 μrad), it has a thousand times better resolution than the first orbiting X-ray telescopes. Its highly [[elliptical orbit|elliptical]] orbit allows continuous observations up to 85 percent of its 65-hour [[orbital period]]. With its ability to make X-ray images of star clusters, supernova remnants, galactic eruptions, and collisions between clusters of galaxies - in its first decade of operation it has transformed astronomer's view of the high-energy universe.<ref>{{cite web |url=http://chandra.harvard.edu/ten/ |title=Chandra :: About Chandra :: The Extraordinary Universe with Chandra |website=chandra.harvard.edu |access-date=22 March 2018 |archive-date=11 March 2011 |archive-url=https://web.archive.org/web/20110311144839/http://chandra.harvard.edu/ten/ |url-status=live }}</ref>

====Compton Gamma Ray Observatory====
The [[Compton Gamma Ray Observatory]] (CGRO) was another of NASA's [[Great Observatories]]. The CGRO was launched April 5, 1991, on Shuttle flight STS-37. At {{cvt|37,000|lb|kg}}, it was the heaviest astrophysical payload ever flown at that time. CGRO was 14 years in development by NASA; TRW was the builder. Gamma radiation is the highest energy-level of electromagnetic radiation, having energies above 100 [[electronvolt|keV]] and frequencies above 10 [[hertz|exahertz]] (10<sup>19</sup> Hz). Gamma radiation is produced by [[atom|sub-atomic]] particle interactions, including those in some astrophysical processes. The continuous flow of cosmic rays bombarding space objects, such as the Moon, generate this radiation. Gamma rays also result in bursts from nuclear reactions. The CGRO was designed to image continuous radiation and to detect bursts.{{citation_needed|date=July 2019}}

MSFC was responsible for the Burst and Transient Source Experiment, (BATSE). This triggered on sudden changes in gamma count-rates lasting 0.1 to 100 s; it was also capable of detecting less impulsive sources by measuring their modulation using the Earth [[occultation]] technique. In nine years of operation, BATSE triggered about 8000 events, of which some 2700 were strong bursts that were analyzed to have come from distant galaxies.{{citation_needed|date=July 2019}}

Unlike the Hubble Space Telescope, the CGRO was not designed for on-orbit repair and refurbishment. Thus, after one of its gyroscopes failed, NASA decided that a controlled crash was preferable to letting the craft come down on its own at random. On June 4, 2000, it was intentionally de-orbited, with the debris that did not burn up falling harmlessly into the Pacific Ocean. At MSFC, [[Gerald J. Fishman]]{{when|date=July 2019}} is the principal investigator of a project to continue examination of data from BATSE and other gamma-ray projects. The 2011 [[Shaw Prize]] was shared by Fishman and Italian [[Enrico Costa (physicist)|Enrico Costa]] for their gamma-ray research.<ref>{{cite news |title=Huntsville NASA scientist shares $1 million Shaw prize for astronomy |date=June 17, 2011 |author=Lee Roop |url=https://www.al.com/breaking/2011/06/huntsville_nasa_scientist_shar.html |website=al.com |access-date=June 6, 2023 |archive-date=June 7, 2023 |archive-url=https://web.archive.org/web/20230607042506/https://www.al.com/breaking/2011/06/huntsville_nasa_scientist_shar.html |url-status=live }}</ref>