Baker, David (2011). NASA Space Shuttle: Owners' Workshop Manual. Somerset, UK: Haynes Manual. ISBN 978-1-84425-866-6. Stevonec, Timothy (January 28, 2014). "Challenger Disaster Home Video Surfaces After 28 Years". The Huffington Post. Archived from the original on February 1, 2017 . Retrieved September 12, 2021. a b Schmidt, William E. (April 30, 1986). "Bodies of Astronauts Flown to Delaware". The New York Times. Archived from the original on June 28, 2021 . Retrieved July 15, 2021. Clendinen, Dudley (May 18, 1986). "Astronaut Buried in Caroline; 35-Year 'Mission' is Complete". The New York Times. Archived from the original on August 29, 2021 . Retrieved July 15, 2021.

The first occurrence of in-flight O-ring erosion occurred on the right SRB on STS-2 in November 1981. [1] :126 In August 1984, a post-flight inspection of the left SRB on STS-41-D revealed that soot had blown past the primary O-ring and was found in between the O-rings. Although there was no damage to the secondary O-ring, this indicated that the primary O-ring was not creating a reliable seal and was allowing hot gas to pass. The amount of O-ring erosion was insufficient to prevent the O-ring from sealing, and investigators concluded that the soot between the O-rings resulted from non-uniform pressure at the time of ignition. [1] :130 [4] :39–42 The January 1985 launch of STS-51-C was the coldest Space Shuttle launch to date. The air temperature was 62°F (17°C) at the time of launch, and the calculated O-ring temperature was 53°F (12°C). Post-flight analysis revealed erosion in primary O-rings in both SRBs. Morton Thiokol engineers determined that the cold temperatures caused a loss of flexibility in the O-rings that decreased their ability to seal the field joints, which allowed hot gas and soot to flow past the primary O-ring. [4] :47 O-ring erosion occurred on all but one ( STS-51-J) of the Space Shuttle flights in 1985, and erosion of both the primary and secondary O-rings occurred on STS-51-B. [1] :131 [4] :50–52,63 Bardan, Roxana (November 10, 2022). "NASA Views Images, Confirms Discovery of Shuttle Challenger Artifact". NASA . Retrieved November 11, 2022. Between 2010 and 2014, 43 Challenger 2 tanks were disposed of as "beyond any economic repair". [30]

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The commission held hearings that discussed the NASA accident investigation, the Space Shuttle program, and the Morton Thiokol recommendation to launch despite O-ring safety issues. On February 15, Rogers released a statement that established the commission's changing role to investigate the accident independent of NASA due to concerns of the failures of the internal processes at NASA. The commission created four investigative panels to research the different aspects of the mission. The Accident Analysis Panel, chaired by Kutyna, used data from salvage operations and testing to determine the exact cause behind the accident. The Development and Production Panel, chaired by Sutter, investigated the hardware contractors and how they interacted with NASA. The Pre-Launch Activities Panel, chaired by Acheson, focused on the final assembly processes and pre-launch activities conducted at KSC. The Mission Planning and Operations Panel, chaired by Ride, investigated the planning that went into mission development, along with potential concerns over crew safety and pressure to adhere to a schedule. Over a period of four months, the commission interviewed over 160 individuals, held at least 35 investigative sessions, and involved more than 6,000 NASA employees, contractors, and support personnel. [1] :206−208 The commission published its report on June 6, 1986. [1] :iii–iv Members of the Rogers Commission arrive at Kennedy Space Center Several memorials have been established in honor of the Challenger disaster. The public Peers Park in Palo Alto, California, features the Challenger Memorial Grove including redwood trees grown from seeds carried aboard Challenger in 1985. [76] Schools and streets have been renamed to include the names of the crew or Challenger. [77] [78] [79] In 1990, a 1/10 scale replica of Challenger in liftoff position was erected in Little Tokyo district of Los Angeles, California. [80] Challenger Point is a mountain peak of the Sangre de Cristo Range. [81] The McAuliffe-Shepard Discovery Center, a science museum and planetarium in Concord, New Hampshire, is named in honor of McAuliffe, a Concord High School teacher, and Alan Shepard, who was from Derry, New Hampshire. [82] Protection [ edit ] Challenger 2 with armour upgrades to the sides of the turret, skirts, bar armour to rear. Smoke grenade launchers visible on turret front. Counter-IED ECM antennas are on the platform on the turret, and additional ECM equipment overhangs the left and right front fenders. A remote controlled weapon systems (RCWS) has also been fitted to the turret. The Challenger 2 is a heavily armoured and well protected tank. [47] The turret and hull are protected by second-generation Chobham armour, also known as Dorchester, the details of which are classified but which is said to have a mass efficiency more than twice that of rolled homogeneous armour against high-explosive anti-tank (HEAT) projectiles. Crew safety was paramount in the design. It uses a solid state electric drive for turret and gun motion, instead of hydraulic systems that can leak fluid into the crew compartment.

Shuttle Crew Said to Have Survived Blast". The Washington Post. November 12, 1988. Archived from the original on August 18, 2020 . Retrieved August 11, 2021.Minor Planet Circulars/Minor Planets and Comets" (PDF). Minor Planet Center – Smithsonian Astrophysical Observatory. March 26, 1986. pp.MPC 10457–10586. Archived (PDF) from the original on July 27, 2021 . Retrieved July 30, 2021. At T+0, Challenger launched from the Kennedy Space Center Launch Complex 39B (LC-39B) at 11:38:00 a.m. [1] :17 [2] :III–76 Beginning at T+0.678 until T+3.375 seconds, nine puffs of dark gray smoke were recorded escaping from the right-hand SRB near the aft strut that attached the booster to the ET. [1] :19 [2] :III-93 It was later determined that these smoke puffs were caused by joint rotation in the aft field joint of the right-hand SRB at ignition. [4] :136 The cold temperature in the joint had prevented the O-rings from creating a seal. Rainfall from the preceding time on the launchpad had likely accumulated within the field joint, further compromising the sealing capability of the O-rings. As a result, hot gas was able to travel past the O-rings and erode them. Molten aluminum oxides from the burned propellant resealed the joint and created a temporary barrier against further hot gas and flame escaping through the field joint. [4] :142 The Space Shuttle main engines (SSMEs) were throttled down as scheduled for maximum dynamic pressure (max q). [2] :III–8–9 [10] During its ascent, the Space Shuttle encountered wind shear conditions beginning at T+37, but they were within design limits of the vehicle and were countered by the guidance system. [1] :20 Plume [ edit ] Plume on right SRB at T+58.788 seconds On 29 January 2023, the UK Ministry of Defence announced that the first Ukrainian troops had arrived in the UK to begin training on Challenger 2. [41] On 8 February, Sunak and Ukrainian President Zelensky paid a visit to Ukrainian soldiers at Lulworth Camp where they were being trained on Challenger 2 tanks by British soldiers from the Royal Tank Regiment and the Queen's Royal Hussars. Sunak used the opportunity to reaffirm the British intention to have the first Challenger 2 tanks delivered to Ukraine by March 2023. [42] a b "Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident, Recommendation VII". NASA. June 1987. Archived from the original on February 24, 2021 . Retrieved August 3, 2021.

Baldoni, John (January 28, 2019). "The Challenger Disaster: A Dramatic Lesson In The Failure To Communicate". Forbes. Archived from the original on September 13, 2021 . Retrieved September 13, 2021. Congressional Space Medal of Honor". NASA. April 28, 2006. Archived from the original on February 20, 2011 . Retrieved July 19, 2021. The tanks deployed to Iraq had been 'desertised' in an effort to avoid the difficulties that had been identified in Challenger 2 during Exercise Saif Sareea II in Oman 18 month earlier. The addition of sand filters and other modifications through a series of Urgent Operational Requirements substantially improved the platform's operational availability.The commander has a panoramic SAGEM VS 580-10 gyrostabilised sight with laser rangefinder. The elevation range is +35° to −35°. The commander's station is equipped with eight periscopes for 360° vision. MoD spokesman, speaking in regard to the Challenger 2 [55] Challenger 2 tanks deployed in Kosovo, September 2000 British officials are buoyed that its tank has been able to protect its Ukrainian crew, and are not bothered by its destruction.

Logsdon, John M. (2018). Ronald Reagan and the Space Frontier. Springer. p.283. ISBN 978-3-319-98962-4. Archived from the original on February 4, 2021 . Retrieved November 21, 2020. Space Shuttle Challenger Monument (Los Angeles, California)". Astronaut Ellison S. Onizuka Memorial. 2021. Archived from the original on April 27, 2021 . Retrieved April 27, 2021.

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Uniquely among NATO main battle tank guns, the L30A1 is rifled and along with its predecessor, the Royal Ordnance L11A5, the only Third Generation Main Battle Tank Guns to use a rifled barrel. This is because the British Army continues to place a premium on the use of high explosive squash head (HESH) rounds in addition to armour-piercing fin-stabilized discarding-sabot (APFSDS) rounds. HESH rounds have a longer range (up to 8 kilometres or 5 miles further) than APFSDS, and are more effective against buildings and thin-skinned vehicles. [45] Malinowski, Tonya (June 29, 2018). "NASA astronaut Ellison Onizuka's soccer ball that survived the Challenger explosion". ESPN. Archived from the original on August 20, 2021 . Retrieved July 19, 2021. Voenny Osvedomitel, a popular pro-war Telegram channel, said on Tuesday the Ukrainian armed forces “resumed a full-scale offensive” around Novodonetske for the first time in over three months. On March 7, Air Force divers identified potential crew compartment debris, which was confirmed the next day by divers from the USS Preserver. [17] :51 [18] The damage to the crew compartment indicated that it had remained largely intact during the initial explosion but was extensively damaged when it impacted the ocean. [16] The remains of the crew were badly damaged from impact and submersion, and were not intact bodies. [19] The USS Preserver made multiple trips to return debris and remains to port, and continued crew compartment recovery until April 4. [17] :51 During the recovery of the remains of the crew, Jarvis's body floated away and was not located until April 15, several weeks after the other remains had been positively identified. [18] [20] Once remains were brought to port, pathologists from the Armed Forces Institute of Pathology worked to identify the human remains, but could not determine the exact cause of death for any of them. [19] [13] Medical examiners in Brevard County disputed the legality of transferring human remains to US military officials to conduct autopsies and refused to issue the death certificates; NASA officials ultimately released the death certificates of the crew members. [21]