Editing STS-31

{{Short description|1990 American crewed spaceflight to deploy the Hubble Space Telescope}}
{{Use American English|date=January 2014}}
{{Use mdy dates|date=November 2022}}
{{Infobox spaceflight
| name               = STS-31
| names_list         = [[Space Transportation System]]-31<br />STS-31R
| image              = 1990 s31 IMAX view of HST release.jpg
| image_caption      = ''Discovery'' deploys the [[Hubble Space Telescope]].
| mission_type       = [[Hubble Space Telescope]] deployment
| operator           = [[NASA]]
| mission_duration   = {{time interval|April 24, 1990, 12:33:51|April 29, 1990, 13:49:57|show=dhms|sep=,}}
| distance_travelled = {{cvt|3328466|km}}
| orbits_completed   = 80
| spacecraft         = {{OV|103}}
| launch_mass        = {{cvt|117586|kg}}
| landing_mass       = {{cvt|85947|kg}}
| payload_mass       = {{cvt|11878|kg}}
| crew_size          = 5
| crew_members       = {{Unbulleted list|[[Loren Shriver]]|[[Charles Bolden]]|[[Bruce McCandless II]]|[[Steven Hawley]]|[[Kathryn D. Sullivan]]}}
| launch_date        = {{Start date text|April 24, 1990, 12:33:51|timezone=yes}}{{nbsp}}[[Coordinated Universal Time|UTC]] (8:33:51{{nbsp}}am{{nbsp}}[[Eastern Daylight Time|EDT]])
| launch_site        = [[Kennedy Space Center|Kennedy]], [[Kennedy Space Center Launch Complex 39B|LC-39B]]
| launch_contractor  = [[Rockwell International]]
| landing_date       = {{End date text|April 29, 1990, 13:49:57|timezone=yes}}{{nbsp}}UTC (6:49:57{{nbsp}}am{{nbsp}}[[Pacific Daylight Time|PDT]])
| landing_site       = [[Edwards Air Force Base|Edwards]], Runway{{nbsp}}22
| orbit_reference    = [[Geocentric orbit]]
| orbit_regime       = [[Low Earth orbit]]
| orbit_periapsis    = {{cvt|613|km}}
| orbit_apoapsis     = {{cvt|615|km}}
| orbit_inclination  = 28.45°
| orbit_period       = 96.70 minutes
| apsis              = gee
| instruments        = {{ubl|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)}}
| insignia           = Sts31 flight insignia.png
| insignia_caption   = STS-31 mission patch
| crew_photo         = Sts-31 crew.jpg
| crew_photo_caption = From left: [[Charles Bolden|Bolden]], [[Steven Hawley|Hawley]], [[Loren Shriver|Shriver]], [[Bruce McCandless II|McCandless]] and [[Kathryn D. Sullivan|Sullivan]]
| programme          = [[Space Shuttle program]]
| previous_mission   = [[STS-36]] (34)
| next_mission       = [[STS-41]] (36)
| programme2         = [[Hubble Space Telescope]] missions
| next_mission2      = [[STS-61]] ({{abbr|SM1|Servicing Mission 1}})
}}

'''STS-31''' was the 35th mission of [[NASA]]'s [[Space Shuttle program]] and the tenth flight of the [[Space Shuttle]] [[Space Shuttle Discovery|''Discovery'']].  The primary purpose of this mission was the deployment of the [[Hubble Space Telescope]] (HST) into [[low Earth orbit]]. ''Discovery'' lifted off from [[Kennedy Space Center Launch Complex 39B|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.{{cn|date=May 2024}}

''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 [[Space Shuttle Columbia|''Columbia'']] on 39A.

== Crew ==
{{Spaceflight crew
| terminology = Astronaut
| position1   = Commander
| crew1_up    = [[Loren Shriver]]
| flights1_up = Second
| position2   = Pilot
| crew2_up    = [[Charles Bolden]]
| flights2_up = Second
| position3   = Mission Specialist 1
| crew3_up    = [[Bruce McCandless II]]
| flights3_up = Second and last
| position4   = Mission Specialist 2<br />Flight Engineer
| crew4_up    = [[Steven Hawley]]
| flights4_up = Third
| position5   = Mission Specialist 3
| crew5_up    = [[Kathryn D. Sullivan]]
| flights5_up = Second
}}

=== Crew seat assignments ===
{| class="wikitable" style="text-align:center"
! Seat<ref name="Spacefacts STS-31">{{cite web|last1=Becker|first1=Joachim|title=Spaceflight mission report: STS-31|url=http://spacefacts.de/mission/english/sts-31.htm|publisher=Spacefacts|access-date=February 26, 2014|archive-url=https://web.archive.org/web/20210107134356/http://spacefacts.de/mission/english/sts-31.htm|archive-date=January 7, 2021|url-status=live}}</ref>
! Launch
! Landing
|rowspan=8| [[File:Space Shuttle seating plan.svg|150px]]<br />Seats 1–4 are on the flight deck.<br />Seats 5–7 are on the mid-deck.
|-
! 1
|colspan=2| Shriver
|-
! 2
|colspan=2| Bolden
|-
! 3
| McCandless
| Sullivan
|-
! 4
|colspan=2| Hawley
|-
! 5
| Sullivan
| McCandless
|-
! 6
|colspan=2 style="background-color:lightgray"| ''Unused''
|-
! 7
|colspan=2 style="background-color:lightgray"| ''Unused''
|}

=== Crew notes ===
This mission was originally to be flown in August 1986 as [[STS-61-J]] using [[Space Shuttle Atlantis|''Atlantis'']], but was postponed due to the [[Space Shuttle Challenger disaster|''Challenger'' disaster]]. [[John Young (astronaut)|John W. Young]] was originally assigned to command this mission,<ref>{{cite book|last1=Janson|first1=Bette R.|editor1-last=Ritchie|editor1-first=Eleanor H.|editor2-last=Saegesser|editor2-first=Lee D.|title=Astronautics and Aeronautics, 1985: A Chronology|date=March 1, 1988|publisher=United States Government Printing Office|location=Washington, D.C.|url=https://ntrs.nasa.gov/api/citations/19890017432/downloads/19890017432.pdf|page=282}} {{PD-notice}}</ref> which would have been his seventh spaceflight, but was reassigned to an administrative position and was replaced by [[Loren Shriver|Loren J. Shriver]] in 1988.<ref name="JSC Press 1988">{{cite web|last1=Carr|first1=Jeffry|title=JSC News Release Log 1988 |url=https://www.nasa.gov/centers/johnson/pdf/83140main_1988.pdf#page=13|work=Lyndon B. Johnson Space Center|publisher=NASA|archive-url=https://web.archive.org/web/20170225161928/https://www.nasa.gov/centers/johnson/pdf/83140main_1988.pdf#page=13|archive-date=February 25, 2017|location=Houston, Texas|page=88-008|date=March 17, 1988|url-status=live}} {{PD-notice}}</ref>

== Mission highlights ==
[[File:STS-31 Launch - GPN-2000-000684.jpg|thumb|upright=1.3|Space Shuttle ''Discovery'' launches from LC-39B for STS-31 with ''Columbia'' on LC-39A in preparation for [[STS-35]].]]
[[File:1990 s31 IMAX view of HST in payload bay.jpg|upright=1.3|thumb|Hubble Space Telescope in the cargo bay of ''Discovery'']]

STS-31 was launched on April 24, 1990, at 12:33:51{{nbsp}}[[Coordinated Universal Time|UTC]] (8:33:51{{nbsp}}am{{nbsp}}[[Eastern Daylight Time|EDT]], local time at the launch site). A launch attempt on April 10, 1990, was scrubbed at T''−''4 minutes for a faulty valve in [[auxiliary power unit]] (APU) number one. The APU was eventually replaced, and the Hubble Space Telescope's batteries were recharged. On launch day, the countdown was briefly halted at T''−''31 seconds when ''Discovery''{{'}}s computers failed to shut down a fuel valve line on ground support equipment. Engineers manually commanded the valve to close and the countdown continued.<ref name="MSER STS-31">{{cite web|publisher=NASA Office of Safety, Reliability, Maintainability and Quality Assurance|title=Misson Safety Evaluation Report for STS-31 – Postflight Edition|url=https://ntrs.nasa.gov/api/citations/19920012273/downloads/19920012273.pdf|archive-url=https://web.archive.org/web/20210107105312/https://ntrs.nasa.gov/api/citations/19920012273/downloads/19920012273.pdf|archive-date=January 7, 2021|location=Washington, D.C.|page=7-1|date=October 15, 1990|url-status=live}} {{PD-notice}}</ref>

The main purpose of this mission was to deploy Hubble. It was designed to operate above the Earth's turbulent and obscuring atmosphere to observe celestial objects at [[ultraviolet]], [[Visible spectrum|visible]] and [[Infrared|near-infrared]] [[wavelength]]s. The Hubble mission was a joint NASA-ESA ([[European Space Agency]]) effort going back to the late 1970s.<ref name="NewScientist 1990-07-07">{{cite news |last1=Gavaghan|first1=Helen|title=Design flaw cripples Hubble telescope|url=https://www.newscientist.com/article/mg12717240-300-design-flaw-cripples-hubble-telescope/|url-status=live|publisher=New Scientist |issue=1724|date=July 7, 1990|archive-url=https://web.archive.org/web/20210107115137/https://www.newscientist.com/article/mg12717240-300-design-flaw-cripples-hubble-telescope/|archive-date=January 7, 2021}}</ref> The rest of the mission was devoted to photography and onboard experiments. To launch HST into an orbit that guaranteed longevity, ''Discovery'' entered an orbit of around {{cvt|613|xx|615|km}}. At one point during the mission, ''Discovery'' briefly reached an [[Apsis|apogee]] of {{cvt|621|km}}, the highest altitude ever reached by a Shuttle orbiter.<ref>{{cite tweet|number=1438322692097286151|user=planet4589|first=Jonathan|last=McDowell|title=Here is a comparison of the STS-31 and STS-82 TLE data (apogee and perigee given in 'conventional height', i.e. geocentric radius minus 6378&nbsp;km). STS-31 clearly a tiny bit higher, as can be seen in the zoomed-in second plot|url=https://twitter.com/planet4589/status/1438322692097286151|access-date=September 16, 2021}}</ref> The record height also permitted the crew to photograph Earth's large-scale geographic features not apparent from lower orbits. Motion pictures were recorded by two IMAX cameras, and the results appeared in the 1994 IMAX film ''[[Destiny in Space]]''.<ref name="Smithsonian IMAX Camera">{{cite web|title=Camera, ICBC, 70&nbsp;mm, IMAX|url=https://airandspace.si.edu/collection-objects/camera-icbc-70mm-imax/nasm_A20120259000|website=National Air and Space Museum|publisher=Smithsonian Institution|access-date=January 7, 2021|archive-url=https://web.archive.org/web/20210107122017/https://airandspace.si.edu/collection-objects/camera-icbc-70mm-imax/nasm_A20120259000 |archive-date=January 7, 2021|url-status=live}}</ref> Experiments on the mission included a biomedical technology study, advanced materials research, particle contamination and ionizing radiation measurements, and a student science project studying zero-gravity effects on electronic arcs. ''Discovery''{{'}}s reentry from its higher-than-usual orbit required a deorbit burn of 4 minutes and 58 seconds, the longest in Shuttle history up to that time.<ref name="STS-31 SSMR">{{cite web |date=May 1990 |title=STS-31 Space Shuttle Mission Report |url=https://ntrs.nasa.gov/api/citations/19920008146/downloads/19920008146.pdf |url-status=live |archive-url=https://web.archive.org/web/20210107114538/https://ntrs.nasa.gov/api/citations/19920008146/downloads/19920008146.pdf |archive-date=January 7, 2021 |publisher=NASA}} {{PD-notice}}</ref> ''Discovery'' orbited the [[Earth]] 80 times during the mission.<ref name="STS-31 SSMR" />

During the deployment of Hubble, one of the observatory's solar arrays stopped as it unfurled. While ground controllers searched for a way to command HST to unreel the [[Solar panels on spacecraft|solar array]], Mission Specialists McCandless and Sullivan began preparing for a contingency [[Extravehicular activity|spacewalk]] in the event that the array could not be deployed through ground control. The array eventually came free and unfurled through ground control while McCandless and Sullivan were pre-breathing inside the partially depressurized airlock.<ref name="Goodman 2009">{{cite conference|last1=Goodman |first1=John L.|last2=Walker |first2=Stephen R.|title=Hubble Servicing Challenges Drive Innovation of Shuttle Rendezvous Technique|url=https://ntrs.nasa.gov/api/citations/20090005185/downloads/20090005185.pdf |conference=32nd Annual AAS Guidance and Control Conference|conference-url=https://aas-rocky-mountain-section.org/|publisher=NASA|place=Breckenridge, Colorado|date=January 31, 2009|page=6|url-status=live|archive-url=https://web.archive.org/web/20210107132314/https://ntrs.nasa.gov/api/citations/20090005185/downloads/20090005185.pdf|archive-date=January 7, 2021}} {{PD-notice}}</ref>

Secondary payloads included the [[IMAX]] Cargo Bay Camera (ICBC) to document operations outside the crew cabin and a handheld IMAX camera for use inside the orbiter. Also included were the Ascent Particle Monitor (APM) to detect particulate matter in the payload bay; a Protein Crystal Growth (PCG) experiment to provide data on growing [[Protein crystallization|protein crystals]] in [[Micro-g environment|microgravity]], [[Radiation]] Monitoring Equipment III (RME III) to measure [[gamma ray]] levels in the crew cabin; Investigations into Polymer Membrane Processing (IPMP) to determine porosity control in the microgravity environment, and an [[Air Force Maui Optical and Supercomputing observatory|Air Force Maui Optical Site]] (AMOS) experiment.<ref name="STS-31 SSMR" />

The mission marked the flight of an {{cvt|5|kg}} [[human skull]], which served as the primary element of "Detailed Secondary Objective 469", also known as the In-flight Radiation Dose Distribution (IDRD) experiment. This joint NASA/[[United States Department of Defense|DoD]] experiment was designed to examine the penetration of [[radiation]] into the human cranium during spaceflight. The female skull was seated in a plastic matrix, representative of tissue, and sliced into ten layers. Hundreds of thermo-luminescent [[dosimeters]] were mounted in the skull's layers to record radiation levels at multiple depths. This experiment, which also flew on [[STS-28]] and [[STS-36]], was located in the shuttle's mid-deck lockers on all three flights, recording radiation levels at different orbital inclinations.<ref name="MacKnight 1991">{{cite book|last1=MacKnight|first1=Nigel|title=Space Year 1991: The Complete Record of the Year's Space Events|date=December 31, 1991|publisher=Motorbooks International|location=Osceola, Wisconsin|isbn=978-0-87938-482-1|page=41}}</ref>

''Discovery'' landed on Runway 22 at [[Edwards Air Force Base]] in [[California]] on April 29, 1990, at 13:49:57{{nbsp}}UTC (6:49:57{{nbsp}}am{{nbsp}}[[Pacific Daylight Time|PDT]], local time at the landing site). The landing had a rollout distance of {{cvt|2705|m}}, took 61 seconds, and marked the first use of carbon brakes on a shuttle. ''Discovery'' was returned to Kennedy Space Center after STS-31 on May 7, 1990.<ref name="Archives STS-31">{{cite web|last1=Ryba|first1=Jeanne|title=STS-31 |url=https://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-31.html|work=Mission Archives|publisher=NASA|archive-url=https://web.archive.org/web/20210107152149/https://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-31.html|archive-date=January 7, 2021|date=November 23, 2007|url-status=live}} {{PD-notice}}</ref>

{{LaunchAttempt
| date1           = 1990-04-10 08:47 AM
| result1         = Scrubbed
| reason1         = Technical
| decision_date1  = 
| decision_clock1 = −4:00
| weathergo1      = 
| notes1          = Faulty valve in auxiliary power unit.<ref name="MSER STS-31" />
| date2           = 1990-04-24, 08:33:51
| result2         = Successful
| reason2         = 
| decision_date2  = 
| decision_clock2 = 
| weathergo2      = 
| notes2          = Countdown was held at T−0:31 when a fuel valve line on ground support equipment failed to shut automatically. The valve was shut manually and the countdown was resumed.<ref name="MSER STS-31" />
}}

== Wake-up calls ==
NASA began a tradition of playing music to astronauts during the [[Project Gemini]], which was first used to wake up a flight crew during [[Apollo 15]]. Each track is specially chosen, often by their families, and usually has a special meaning to an individual member of the crew, or is applicable to their daily activities.<ref name="Wakeup Calls">{{cite web|url=https://history.nasa.gov/wakeup%20calls.pdf |title=Chronology of Wakeup Calls|last=Fries|first=Colin|work=History Division|publisher=NASA|date=March 13, 2015|url-status=dead|archive-url=https://web.archive.org/web/20210105144032/https://history.nasa.gov/wakeup%20calls.pdf|archive-date=January 5, 2021|access-date=January 5, 2021}} {{PD-notice}}</ref>

{| class="wikitable"
|-
! Flight Day
! Song
! Artist/Composer
|-
| Day 2
| "Space is Our World"
| Private Numbers
|-
| Day 3
| "[[Shout (The Isley Brothers song)|Shout]]"
| [[Otis Day and the Knights]]
|-
| Day 4
| "[[Kokomo (song)|Kokomo]]"
| [[Beach Boys]]
|-
| Day 5
| "Cosmos"
| [[Frank Hayes (musician)|Frank Hayes]]
|-
| Day 6
| "[[Rise and Shine (Raffi album)|Rise and Shine]]"
| [[Raffi (musician)|Raffi]]
|}

== Gallery ==
<gallery>
File:1990 s31 HST closeout.jpg|Hubble at the pad
File:Liftoff STS-31.jpg|Liftoff of ''Discovery'' with the Hubble Space Telescope on board
File:1990 s31 HST Bay.jpg|Low hover position
File:HST over Bahamas.jpg|High over [[Cuba]]
File:Hubble Solar Array Deployment STS-31.jpg|Solar array deployment
File:Scanned highres STS031 STS031-76-39 copy.jpg|Hubble drifts away over [[Peru]].
File:Florida from STS-31.jpg|Florida and [[The Bahamas]]
File:Sts-31 Landing.jpg|''Discovery'' returns home.
</gallery>

== See also ==
{{Portal|Spaceflight}}
* [[List of human spaceflights]]
* [[List of Space Shuttle missions]]
* [[Outline of space science]]
* [[Space Shuttle]]

== References ==
{{Reflist|30em}}

== External links ==
{{Commons}}
* [http://science.ksc.nasa.gov/shuttle/missions/sts-31/mission-sts-31.html NASA mission summary] {{Webarchive|url=https://web.archive.org/web/20110815191242/http://science.ksc.nasa.gov/shuttle/missions/sts-31/mission-sts-31.html |date=August 15, 2011 }}
* {{YouTube|id=NEr7pjhplWI|title=STS-31 Post Flight Crew Presentation}}
* {{YouTube|id=9WT3iCLf5As|title=STS-31 Post Flight Conference}}
* [https://plus.nasa.gov/video/sts-31-mission-highlights/ STS-31 Mission Highlights]
{{Space Shuttle Discovery}}
{{Hubble Space Telescope}}
{{All U.S. Space Shuttle Missions}}
{{Orbital launches in 1990}}
{{Authority control}}

[[Category:Space Shuttle missions]]
[[Category:Edwards Air Force Base]]
[[Category:Spacecraft launched in 1990]]
[[Category:Hubble Space Telescope]]