|This article needs additional citations for verification. (October 2007)|
Human spaceflight (also referred to as manned spaceflight) is space travel with a crew aboard the spacecraft. When a spacecraft is crewed, it can be operated directly, as opposed to being remotely operated or autonomous.
The first human spaceflight was launched by the Soviet Union on 12 April 1961 as a part of the Vostok program, with cosmonaut Yuri Gagarin aboard. Humans have been continually present in space for 15 years and 26 days on the International Space Station.
Since the retirement of the US Space Shuttle in 2011, only Russia and China have maintained domestic human spaceflight capability with the Soyuz program and Shenzhou program. Currently, all crewed flights to the International Space Station use Soyuz vehicles, which remain attached to the station to allow quick return if needed. The United States is developing commercial crew transportation to facilitate domestic access to ISS and low Earth orbit, as well as the Orion vehicle for beyond-low Earth orbit applications.
While spaceflight has typically been a government-directed activity, commercial spaceflight has gradually been taking on a greater role. The first private human spaceflight took place on 21 June 2004, when SpaceShipOne conducted a suborbital flight, and a number of non-governmental companies have been working to develop a space tourism industry. NASA has also played a role to stimulate private spaceflight through programs such as Commercial Orbital Transportation Services (COTS) and Commercial Crew Development (CCDev). With its 2011 budget proposals released in 2010, the Obama administration moved towards a model where commercial companies would supply NASA with transportation services of both crew and cargo to low Earth orbit. The vehicles used for these services could then serve both NASA and potential commercial customers. Commercial resupply of ISS began two years after the retirement of the Shuttle, and commercial crew launches could begin by 2017.
- 1 History
- 2 Space programs
- 3 National spacefaring attempts
- 4 Safety concerns
- 5 See also
- 6 References
- 7 External links
First human spaceflights
|Suborbital human spaceflight|
|Orbital human spaceflight|
|Lunar human spaceflight|
The first human spaceflight took place on 12 April 1961, when cosmonaut Yuri Gagarin made one orbit around the Earth aboard the Vostok 1 spacecraft, launched by the Soviet space program. Valentina Tereshkova became the first woman in space aboard Vostok 6 on 16 June 1963. Both spacecraft were launched by Vostok 3KA launch vehicles. Alexei Leonov made the first spacewalk when he left Voskhod 2 on 8 March 1965. Svetlana Savitskaya became the first woman to do so on 25 July 1984.
The United States became the second nation to put a human in space with the suborbital flight of astronaut Alan Shepard aboard Freedom 7 as part of Project Mercury. The spacecraft was launched on 5 May 1961 on a Redstone rocket. The first U.S. orbital flight was that of John Glenn aboard Friendship 7, launched 20 February 1962 on an Atlas rocket. From 1981 to 2011, the U.S. conducted all its human spaceflight missions with reusable space shuttles. Sally Ride became the first American woman in space in 1983. Eileen Collins was the first female shuttle pilot, and with shuttle mission STS-93 in 1999 she became the first woman to command a U.S. spacecraft.
China became the third nation to achieve independent human spaceflight capability when Yang Liwei launched into space on a Chinese-made vehicle, the Shenzhou 5, on 15 October 2003. The first Chinese woman, Liu Yang, was launched in June 2012 aboard Shenzhou 9. Previous European (Hermes) and Japanese (HOPE-X) domestic human spaceflight programs were abandoned after years of development, as was the first Chinese attempt, the Shuguang spacecraft.
The farthest destination for a human spaceflight mission has been the Moon. The only manned missions to the Moon have been those conducted by NASA as part of the Apollo program. The first such mission, Apollo 8, orbited the Moon but did not land. The first Moon landing mission was Apollo 11, during which—on 21 July 1969—Neil Armstrong and Buzz Aldrin became the first people to set foot on the Moon. Six missions landed in total, numbered Apollo 11–17, excluding Apollo 13. Altogether 12 men walked on the Moon, the only humans to have been on an extraterrestrial body in history. The Soviet Union discontinued its program for lunar orbiting and landing of human spaceflight missions in 1974 when Valentin Glushko became General Designer of NPO Energiya.
The longest single human spaceflight is that of Valeri Polyakov, who left Earth on 8 January 1994, and did not return until 22 March 1995 (a total of 437 days 17 h 58 min 16 s). Sergei Krikalyov has spent the most time of anyone in space, 803 days, 9 hours, and 39 minutes altogether. The longest period of continuous human presence in space is 15 years and 26 days on the International Space Station, exceeding the previous record of almost 10 years (or 3,634 days) held by Mir, spanning the launch of Soyuz TM-8 on 5 September 1989 to the landing of Soyuz TM-29 on 28 August 1999.
For many years beginning in 1961, only two countries, the USSR (later Russia) and the United States, had their own astronauts. Citizens of other nations flew in space, beginning with the flight of Vladimir Remek, a Czech, on a Soviet spacecraft on 2 March 1978, in the Interkosmos programme. As of 2010[update], citizens from 38 nations (including space tourists) have flown in space aboard Soviet, American, Russian, and Chinese spacecraft.
Valentina Tereshkova, the first woman in space, 1963
Neil Armstrong, the first person to set foot on the surface of the Moon, 1969
Post-shuttle gap in United States human spaceflight capability
Under the Bush administration, the Constellation Program included plans for retiring the Shuttle program and replacing it with the capability for spaceflight beyond low Earth orbit. In the 2011 United States federal budget, the Obama administration cancelled Constellation for being over budget and behind schedule while not innovating and investing in critical new technologies. For beyond low earth orbit human spaceflight NASA is developing the Orion spacecraft to be launched by the Space Launch System. Under the Commercial Crew Development plan, NASA will rely on transportation services provided by the private sector to reach low earth orbit, such as Space X's Falcon 9/Dragon V2, Sierra Nevada Corporation's Dream Chaser, or Boeing's CST-100. The period between the retirement of the shuttle in 2011 and the initial operational capability of new systems in 2017, similar to the gap between the end of Apollo in 1975 and the first space shuttle flight in 1981, is referred to by a presidential Blue Ribbon Committee as the U.S. human spaceflight gap. Commercial sub-orbital spacecraft aimed at the space tourism market such as Scaled Composites SpaceshipTwo to be operated by Virgin Galactic, and XCOR's Lynx spaceplane are under development and could reach space before 2017.
The Indian Space Research Organization (ISRO) begun work on pre project activities of human space flight mission programme. The objective of Human Spaceflight Programme is to undertake a human spaceflight mission to carry a crew of two to Low Earth Orbit (LEO) and return them safely to a predefined destination on earth. The programme is proposed to be implemented in defined phases. Currently, the pre project activities are progressing with a focus on the development of critical technologies for subsystems such as Crew Module (CM), Environmental control and Life Support System (ECLSS), Crew Escape System, etc. A study for undertaking human space flight to carry human beings to low earth orbit and ensure their safe return has been made by the department. The department has initiated pre-project activities to study technical and managerial issues related to undertaking crewed missions with an aim to build and demonstrate the country’s capability. The program envisages the development of a fully autonomous orbital vehicle carrying 2 or 3 crew members to about 300 km low earth orbit and their safe return.
The following space vehicles and spaceports are currently used for launching human spaceflights:
- Soyuz spacecraft (Soviet/Russian) on Soyuz launch vehicle, launched from Baikonur Cosmodrome
- Shenzhou spacecraft (Chinese) on Long March rocket, launched from Jiuquan Satellite Launch Center
The following space stations are currently maintained in Earth orbit for human spaceflight:
- International Space Station (US and Russia) assembled in orbit: altitude 409 kilometers (221 nautical miles), 51.65° inclination; crews transported by Soyuz spacecraft
- Tiangong-1 (Chinese): altitude 363 kilometers (196 nautical miles), 42.77° inclination; crews transported by Shenzhou spacecraft
Space vehicles are spacecraft used for transportation between the Earth's surface and outer space, or between locations in outer space. The following space vehicles have been used in the past for human spaceflight, with the spaceports they were launched from:
- X-15 high altitude research aircraft (US), from Edwards Air Force Base, entered outer space twice in 1963
- Vostok capsule (Soviet) on Vostok-K launch vehicle, from Baikonur Cosmodrome
- Mercury capsule (US) on Mercury-Redstone Launch Vehicle for suborbital flights and Atlas LV-3B for orbital flights, from Cape Canaveral Air Force Station (CCAFS)
- Voskhod capsule (Soviet) on Voskhod launch vehicle, from Baikonur Cosmodrome
- Gemini capsule (US) on Titan II launch vehicle, from Cape Kennedy (CCAFS)
- Apollo spacecraft (US) on Saturn IB and Saturn V launch vehicles, from Cape Kennedy amd Kennedy Space Center (KSC)
- Space Shuttle (US) from KSC
- SpaceShipOne suborbital space plane (US, private) with White Knight from Mojave Spaceport
Space stations are designed for human habitation in orbit for extended periods. The first stations were designed for sorties (temporary individual missions), while later ones have been designed for continuous, permanent or semi-permanent habitation. The following space stations have been maintained in Earth orbit in the past:
- Salyut (Soviet), a series of sortie stations, ostensibly for civilian purposes; four successful
- Almaz (Soviet), a series of three military sortie stations; these were disguised as Salyuts
- Skylab, a (US) sortie station: altitude 270 nautical miles (500 kilometers), 50° inclination; launched 14 May 1973; manned for 167 days in three missions; uncontrolled reentry 11 July 1979
- Mir (Soviet/Russian), the first semi-permanent space station: altitude 354 kilometers (191 nautical miles), 51.6° inclination; constructed in orbit 20 February 1986 to 23 April 1996; occupied 4,592 days; reentered 23 March 2001
Numerous private companies attempted human spaceflight programs in an effort to win the $10 million Ansari X Prize. The first private human spaceflight took place on 21 June 2004, when SpaceShipOne conducted a suborbital flight. SpaceShipOne captured the prize on 4 October 2004, when it accomplished two consecutive flights within one week. SpaceShipTwo, launching from the carrier aircraft White Knight Two, is planned to conduct regular suborbital space tourism.
Most of the time, the only humans in space are those aboard the ISS, whose crew of six spends up to six months at a time in low Earth orbit.
National spacefaring attempts
- This section lists all nations which have explored human spaceflight programs. This should not to be confused with nations with citizens who have traveled into space including space tourists, flown or intended to fly by foreign country's or non-domestic private space systems – these are not counted as national spacefaring attempts in this list.
|Nation/Organization||Space agency||Term(s) for space traveler||First launched astronaut||Date||Spacecraft||Launcher||Type|
| Union of Soviet Socialist Republics
|Soviet space program
(OKB-1 Design Bureau)
|космонавт (same word in:) (Russian)(Ukrainian)
|Yuri Gagarin||12 April 1961||Vostok spacecraft||Vostok||Orbital|
|United States of America||National Aeronautics and Space Administration (NASA)||astronaut
|Alan Shepard (suborbital)||5 May 1961||Mercury spacecraft||Redstone||Suborbital|
|United States of America||National Aeronautics and Space Administration (NASA)||astronaut
|John Glenn (orbital)||20 February 1962||Mercury spacecraft||Atlas LV-3B||Orbital|
|People's Republic of China||Space program of the People's Republic of China||宇航员 (Chinese)
|...||1973 (abandoned)||Shuguang 1||Long March 2A||-|
|People's Republic of China||Space program of the People's Republic of China||宇航员 (Chinese)
|...||1981 (abandoned)||Piloted FSW||Long March 2||-|
|European Space Agency||CNES / European Space Agency (ESA)||spationaute (French)
|...||1992 (abandoned)||Hermes||Ariane V||-|
||Russian Federal Space Agency (Roscosmos)
|Alexander Viktorenko, Alexander Kaleri||17 March 1992||Soyuz-TM||Soyuz-U2||Soyuz TM-14 to MIR|
| Ba'athist Iraq
|...||رجل فضاء (Arabic)
رائد فضاء (Arabic)
ملاح فضائي (Arabic)
|...||2001 (abandoned)||...||Tammouz 2 or 3||-|
|State of Japan||National Space Development Agency of Japan (NASDA)||宇宙飛行士 (Japanese)
|People's Republic of China||China National Space Administration (CNSA)||太空人 (Chinese)
|Yang Liwei||15 October 2003||Shenzhou spacecraft||Long March 2F||Orbital|
|India||Indian Space Research Organisation (ISRO)||Vyomanaut
|...||after 2017 ||Orbital Vehicle (OV)||GSLV Mk III||-|
|Islamic Republic of Iran||Iranian Space Agency (ISA)||کیهان نورد (Persian)
kayhan navard 
|...||2017 (planned)||ISA manned spacecraft||...||-|
|European Space Agency||European Space Agency (ESA)||astronaut||...||2020 (approved conceptually but full development not begun)||ARV phase-2||Ariane V||-|
|State of Japan||Japan Aerospace Exploration Agency (JAXA)||宇宙飛行士 (Japanese)
|...||2025 (planned)||HTV-based spacecraft||H-IIB||-|
There are two main sources of hazard in space flight: those due to the environment of space which make it hostile to the human body, and the potential for mechanical malfunctions of the equipment required to accomplish space flight.
Planners of human spaceflight missions face a number of safety concerns.
The immediate needs for breathable air and drinkable water are addressed by the life support system of the spacecraft.
Medical data from astronauts in low earth orbits for long periods, dating back to the 1970s, show several adverse effects of a microgravity environment: loss of bone density, decreased muscle strength and endurance, postural instability, and reductions in aerobic capacity. Over time these deconditioning effects can impair astronauts’ performance or increase their risk of injury.
In a weightless environment, astronauts put almost no weight on the back muscles or leg muscles used for standing up. Those muscles then start to weaken and eventually get smaller. If there was an emergency at landing, the loss of muscles, and consequently the loss of strength could be a serious problem. Astronauts can lose up to 20% of their muscle mass on spaceflights lasting five to eleven days. When they return to Earth, they will be considerably weakened and will be out of action for a while. Those who return from long-duration flights are not even allowed to drive a car for the next 21 days.
Astronauts experiencing weightlessness will often lose their orientation, get motion sickness, and lose their sense of direction as their bodies try to get used to a weightless environment. When they get back to Earth, or any other mass with gravity, they have to readjust to the gravity and may have problems standing up, focusing their gaze, walking and turning. Importantly, those body motor disturbances after changing from different gravities only get worse the longer the exposure to little gravity. These changes will affect operational activities including approach and landing, docking, remote manipulation, and emergencies that may happen while landing. This can be a major roadblock to mission success.
In addition, after long space flight missions, male astronauts may experience severe eyesight problems. Such eyesight problems may be a major concern for future deep space flight missions, including a manned mission to the planet Mars.
Without proper shielding, the crews of missions beyond low Earth orbit (LEO) might be at risk from high-energy protons emitted by solar flares. Lawrence Townsend of the University of Tennessee and others have studied the most powerful solar flare ever recorded. That flare was seen by the British astronomer Richard Carrington in September 1859. Radiation doses astronauts would receive from a Carrington-type flare could cause acute radiation sickness and possibly even death.
There is also some scientific concern that extended spaceflight might slow down the body’s ability to protect itself against diseases. Some of the problems are a weakened immune system and the activation of dormant viruses in the body. Radiation can cause both short and long term consequences to the bone marrow stem cells which create the blood and immune systems. Because the interior of a spacecraft is so small, a weakened immune system and more active viruses in the body can lead to a fast spread of infection.
During long missions, astronauts are isolated and confined into small spaces. Depression, cabin fever and other psychological problems may impact the crew's safety and mission success.
Astronauts may not be able to quickly return to Earth or receive medical supplies, equipment or personnel if a medical emergency occurs. The astronauts may have to rely for long periods on their limited existing resources and medical advice from the ground.
Space flight requires much higher velocities than ground or air transportation, which in turn requires the use of high energy density propellants for launch, and the dissipation of large amounts of energy, usually as heat, for safe reentry through the Earth's atmosphere.
Since rockets carry the potential for fire or explosive destruction, space capsules generally employ some sort of launch escape system, consisting either of a tower-mounted solid fuel rocket to quickly carry the capsule away from the launch vehicle (employed on Mercury, Apollo, and Soyuz), or else ejection seats (employed on Vostok and Gemini) to carry astronauts out of the capsule and away for individual parachute landing.
Such a system is not always practical for multiple crew member vehicles (particularly spaceplanes), depending on location of egress hatch(es). When the single-hatch Vostok capsule was modified to become the 2 or 3-person Voskhod, the single-cosmonaut ejection seat could not be used, and no escape tower system was added. The two Voskhod flights in 1964 and 1965 avoided launch mishaps. The Space Shuttle carried ejection seats and escape hatches for its pilot and copilot in early flights, but these could not be used for passengers who sat below the flight deck on later flights, and so were discontinued.
In the only usage of a launch escape system on a manned flight, the Soyuz 7K-ST No. 16L launch on September 26, 1983 was aborted by a launch vehicle fire 90 seconds before liftoff. Both cosmonauts aboard landed safely.
The only crew fatality during launch occurred on January 28, 1986, when the Space Shuttle Challenger broke apart 73 seconds after liftoff, due to failure of a solid rocket booster seal which caused separation of the booster and failure of the external fuel tank, resulting in explosion of the fuel. All seven crew members were killed.
Reentry and landing
The crew of seven aboard the Space Shuttle Columbia were killed on reentry after completing a successful mission in space on February 1, 2003. A wing leading edge reinforced carbon-carbon heat shield had been damaged by a piece of frozen external tank foam insulation which broke off and struck the wing during launch. Hot reentry gasses entered and destroyed the wing structure, leading to breakup of the orbiter vehicle.
There are two basic choices for an artificial atmosphere: either an Earth-like mixture of oxygen in an inert gas such as nitrogen or helium, or pure oxygen, which can be used at lower than standard atmospheric pressure. A nitrogen-oxygen mixture is used in the International Space Station and Soyuz spacecraft, while low-pressure pure oxygen is commonly used in space suits for extravehicular activity.
Use of a gas mixture carries risk of decompression sickness (commonly known as "the bends") when transitioning to or from the pure oxygen space suit environment. There have also been instances of injury and fatalities caused by suffocation in the presence of too much nitrogen and not enough oxygen.
- In 1960, McDonnell Aircraft test pilot G.B. North passed out and was seriously injured when testing a Mercury cabin / spacesuit atmosphere system in a vacuum chamber, due to nitrogen-rich air leaking from the cabin into his space suit feed. This incident led NASA to decide on a pure oxygen atmosphere for the Mercury, Gemini, and Apollo spacecraft.
- In 1981, three pad workers were killed by a nitrogen-rich atmosphere in the aft engine compartment of the Space Shuttle Columbia at the Kennedy Space Center Launch Complex 39.
- In 1995, two pad workers were similarly killed by a nitrogen leak in a confined area of the Ariane 5 launch pad at Guiana Space Centre.
A pure oxygen atmosphere carries risk of fire. The original design of the Apollo spacecraft used pure oxygen at greater than atmospheric pressure prior to launch. An electrical fire started in the cabin of Apollo 1 during a ground test at Cape Kennedy Air Force Station Launch Complex 34 on January 27, 1967, and spread rapidly. The high pressure (increased even higher by the fire) prevented removal of the plug door hatch cover in time to rescue the crew. All three, Gus Grissom, Edward H. White, and Roger Chaffee, were killed. This led NASA to use a nitrogen/oxygen atmosphere before launch, and low pressure pure oxygen only in space.
The March 1966 Gemini 8 mission was aborted in orbit when an attitude control system thruster stuck in the on position, sending the craft into a dangerous spin which threatened the lives of Neil Armstrong and David Scott. Armstrong had to shut the control system off and use the reentry control system to stop the spin. The craft made an emergency reentry and the astronauts landed safely. The most probable cause was determined to be an electrical short due to a static electricity discharge, which caused the thruster to remain powered even when switched off. The control system was modified to put each thruster on its own isolated circuit.
The third lunar landing expedition Apollo 13 in April 1970, was aborted and the lives of the crew, James Lovell, Jack Swigert and Fred Haise, were threatened by failure of a cryogenic liquid oxygen tank en route to the Moon. The tank burst when electrical power was applied to internal stirring fans in the tank, causing the immediate loss of all of its contents, and also damaging the second tank, causing the loss of its remaining oxygen in a span of 130 minutes. This in turn caused loss of electrical power provided by fuel cells to the command spacecraft. The crew managed to return to Earth safely by using the lunar landing craft as a "life boat". The tank failure was determined to be caused by two mistakes. The tank's drain fitting had been damaged when it was dropped during factory testing. This necessitated use of its internal heaters to boil out the oxygen after a pre-launch test, which in turn damaged the fan wiring's electrical insulation, because the thermostats on the heaters did not meet the required voltage rating due to a vendor miscommunication.
As of 2015[update], 18 crew members have died during actual spaceflight missions (see table). Over 100 others have died in accidents during activity directly related to spaceflight or testing.
|Year||Deaths||Mission||Known or likely cause||Accident description|
|1967||1||Soyuz 1||Trauma from crash landing||Landing parachutes malfunctioned, resulting in a crash landing.|
|1971||3||Soyuz 11||Asphyxia||Valve opened upon Orbital Module separation before re-entry, causing descent module to depressurize. The crew are considered to be the only humans to have died in space - all other disasters on this list occurred well below the Kármán line that marks the edge of space.|
|1986||7||STS-51L Space Shuttle Challenger||Asphyxia from cabin breach or trauma from water impact||An O-ring inter-segment seal in the right Solid Rocket Booster failed, allowing hot gases to penetrate the casing of the booster. Escaping hot exhaust gas burned through a strut connecting the booster to the External Tank, which led to failure of the tank. The result was rapid combustion of the fuel in the external tank which gave the appearance of an explosion. The orbiter itself did not explode, but rather broke up due to abnormal aerodynamic forces.|
|2003||7||STS-107 Space Shuttle Columbia||Asphyxia from cabin breach, trauma from dynamic load environment as orbiter broke up||During launch, a piece of insulation foam broke off of the External Tank and struck the left wing, damaging a reinforced carbon-carbon panel on the wing's leading edge. Although the foam strike was detected after the launch, it was not seen as a concern, and the extent of the damage went undetected. As the shuttle re-entered the atmosphere, hot atmospheric gases penetrated through the hole, leading to structural failure of the wing. Eventually, the shuttle lost control and subsequently disintegrated.|
- Tourism on Moon
- List of human spaceflight programs
- List of human spaceflights
- List of spaceflight records
- Mars to Stay
- Mothers in space
- Space medicine
- Manned Mars rover
- "FY 2011 Budget". NASA.
- "NASA Hails Success of Commercial Space Program". nasa.gov. Retrieved 24 July 2014.
- Siddiqi, Asif. Challenge To Apollo The Soviet Union and The Space Race, 1945–1974. NASA. p. 832.
- Congressional watchdog finds NASA’s new rocket is in trouble. Orlando Sentinel blog summary of official reports. 3 November 2008
- Klamper, Amy (8 September 2009) White House Panel Spells Out Human Spaceflight Options for NASA. Space News
- The Indian Space Research Organization (ISRO)Future Programme.
- "X-15 Hypersonic Research Program". NASA.
- According to a press-release of Iraqi News Agency of 5 December 1989 about the first (and last) test of the Tammouz space launcher, Iraq intended to develop manned space facilities by the end of the century. These plans were put to an end by the Gulf War of 1991 and the economic hard times that followed.
- Press Trust of India. "Human space flight mission off ISRO priority list". Retrieved 18 August 2013.
- كيهان نورد (cosmonaut). Noojum.com. Retrieved on 7 August 2011.
- PressTV: 'Iran to put astronaut in space in 2017'. Presstv.ir. Retrieved on 7 August 2011.
- "Iran aims to send man into space by 2019". BBC News. 23 July 2010.
- Amos, Jonathan (7 July 2009). "Europe targets manned spaceship". BBC News. Retrieved 27 March 2010.
- Apollo-like capsule chosen for Crew Space Transportation System, 22 May 2008
- "Jules Verne" Automated Transfer Vehicle (ATV) Re-entry. Information Kit (PDF) . Updated September 2008. European Space Agency. Retrieved on 7 August 2011.
- Amos, Jonathan (26 November 2008). "Europe's 10bn-euro space vision". BBC News. Retrieved 27 March 2010.
- Chang, Kenneth (27 January 2014). "Beings Not Made for Space". New York Times. Retrieved 27 January 2014.
- Mann, Adam (23 July 2012). "Blindness, Bone Loss, and Space Farts: Astronaut Medical Oddities". Wired. Retrieved 23 July 2012.
- Cherry, Jonathan D.; Frost, Jeffrey L.; Lemere, Cynthia A.; Williams, Jacqueline P.; Olschowka, John A.; O'Banion, M. Kerry (2012). "Galactic Cosmic Radiation Leads to Cognitive Impairment and Increased Aβ Plaque Accumulation in a Mouse Model of Alzheimer’s Disease". PLOS ONE 7 (12): e53275. doi:10.1371/journal.pone.0053275. PMC 3534034. PMID 23300905. Retrieved 7 January 2013.
- "Study Shows that Space Travel is Harmful to the Brain and Could Accelerate Onset of Alzheimer's". SpaceRef. 1 January 2013. Retrieved 7 January 2013.
- Cowing, Keith (3 January 2013). "Important Research Results NASA Is Not Talking About (Update)". NASA Watch. Retrieved 7 January 2013.
- Dunn, Marcia (October 29, 2015). "Report: NASA needs better handle on health hazards for Mars". AP News. Retrieved October 30, 2015.
- Staff (October 29, 2015). "NASA's Efforts to Manage Health and Human Performance Risks for Space Exploration (IG-16-003)" (PDF). NASA. Retrieved October 29, 2015.
- "Exploration Systems Human Research Program – Exercise Countermeasures". NASA.
- "NASA Information: Muscle Atrophy" (PDF). NASA. Retrieved 20 November 2015.
- "Earth Living Is Tough for Astronaut Used to Space". Space.com. Retrieved 2015-11-21.
- Mader, T. H.; et al. (2011). "Optic Disc Edema, Globe Flattening, Choroidal Folds, and Hyperopic Shifts Observed in Astronauts after Long-duration Space Flight". Ophthalmology (journal) 118 (10): 2058–2069. doi:10.1016/j.ophtha.2011.06.021. PMID 21849212.
- Puiu, Tibi (9 November 2011). "Astronauts’ vision severely affected during long space missions". zmescience.com. Retrieved 9 February 2012.
- News (CNN-TV, 02/09/2012) – Video (02:14) – Male Astronauts Return With Eye Problems
- "Spaceflight Bad for Astronauts' Vision, Study Suggests". Space.com. 13 March 2012. Retrieved 14 March 2012.
- Kramer, Larry A.; et al. (13 March 2012). "Orbital and Intracranial Effects of Microgravity: Findings at 3-T MR Imaging". Radiology (journal). doi:10.1148/radiol.12111986. Retrieved 14 March 2012.
- Fong, MD, Kevin (12 February 2014). "The Strange, Deadly Effects Mars Would Have on Your Body". Wired (magazine). Retrieved 12 February 2014.
- Kerr, Richard (31 May 2013). "Radiation Will Make Astronauts' Trip to Mars Even Riskier". Science 340 (6136): 1031. doi:10.1126/science.340.6136.1031. Retrieved 31 May 2013.
- Battersby, Stephen (21 March 2005). "Superflares could kill unprotected astronauts". New Scientist.
- Space Radiation Hazards and the Vision for Space Exploration. NAP. 2006. ISBN 0-309-10264-2.
- Gueguinou, N.; Huin-Schohn, C.; Bascove, M.; Bueb, J.-L.; Tschirhart, E.; Legrand-Frossi, C.; Frippiat, J.-P. (2009). "Could spaceflight-associated immune system weakening preclude the expansion of human presence beyond Earth's orbit". Journal of Leukocyte Biology 86 (5): 1027–1038. doi:10.1189/jlb.0309167. PMID 19690292.
- Giblin, Kelly A. (Spring 1998). "'Fire in the Cockpit!'". American Heritage of Invention & Technology (American Heritage Publishing) 13 (4). Archived from the original on November 20, 2008. Retrieved March 23, 2011.
- NASA - 1981 KSC Chronology Part 1 - pages 84, 85, 100; Part 2 - pages 181, 194, 195,
- "Fatal accident at the Guiana Space Centre", ESA Portal, May 5, 1993
- Orloff, Richard W. (September 2004) [First published 2000]. "Apollo 1 - The Fire: 27 January 1967". Apollo by the Numbers: A Statistical Reference. NASA History Division, Office of Policy and Plans. NASA History Series (Washington, D.C.: NASA). ISBN 0-16-050631-X. LCCN 00061677. NASA SP-2000-4029. Retrieved July 12, 2013.
- "Report from Joseph P. Kerwin, biomedical specialist from the Johnson Space Center in Houston, Texas, relating to the deaths of the astronauts in the Challenger accident". NASA.
- "COLUMBIA CREW SURVIVAL INVESTIGATION REPORT" (PDF). NASA.gov. NASA. Retrieved July 2014.
- David Darling: The complete book of spaceflight. From Apollo 1 to Zero gravity. Wiley, Hoboken NJ 2003, ISBN 0-471-05649-9.
- Wiley J. Larson (Hrsg.): Human spaceflight – mission analysis and design. McGraw-Hill, New York NY 2003, ISBN 0-07-236811-X.
- Donald Rapp: Human missions to Mars – enabling technologies for exploring the red planet. Springer u. a., Berlin u. a. 2008, ISBN 978-3-540-72938-9.
- Haeuplik-Meusburger: Architecture for Astronauts – An Activity based Approach. Springer Praxis Books, 2011, ISBN 978-3-7091-0666-2
- NASA Human Space Flight
- Human Spaceflight Profile by NASA's Solar System Exploration
- Transitioning to the NASA Constellation Program
- U.S. Spaceflight History