Editing Human spaceflight (section)

== History ==
{{Main|History of spaceflight}}

=== Cold War era ===
{{Main|Space Race}}
[[File:Vostok spacecraft replica.jpg|thumb|180px|Replica of the [[Vostok programme|Vostok]] space capsule, which carried the first human into orbit, at [[Technik Museum Speyer]]]]
[[File:Sigma7-1.jpg|thumb|[[Project Mercury|Mercury]] space capsule, which carried the first Americans into orbit, on display at the [[Astronaut Hall of Fame]], Titusville, Florida]]
[[File:X-15 in flight.jpg|thumb|[[North American X-15]], hypersonic rocket-powered aircraft, which reached the edge of space]]
[[File:As11-40-5886.jpg|thumb|right|[[Neil Armstrong]], one of the first two people to land on the Moon and the first to walk on the lunar surface, July 1969]]

Human spaceflight capability was first developed during the [[Cold War]] between the United States and the Soviet Union (USSR). These nations developed [[intercontinental ballistic missile]]s for the delivery of [[nuclear weapon]]s, producing rockets large enough to be adapted to carry the first [[artificial satellite]]s into [[low Earth orbit]].

After the first satellites were launched in 1957 and 1958 by the Soviet Union, the US began work on [[Project Mercury]], with the aim of launching men into orbit. The USSR was secretly pursuing the [[Vostok programme|Vostok program]] to accomplish the same thing, and launched the first human into space, the cosmonaut [[Yuri Gagarin]]. On 12 April 1961, Gagarin was launched aboard [[Vostok 1]] on a [[Vostok 3KA]] rocket and completed a single orbit. On 5 May 1961, the US launched its first [[astronaut]], [[Alan Shepard]], on a suborbital flight aboard ''[[Freedom 7]]'' on a [[Mercury-Redstone Launch Vehicle|Mercury-Redstone rocket]]. Unlike Gagarin, Shepard manually [[Spacecraft attitude control|controlled his spacecraft's attitude]].<ref>{{cite book |last1=Furniss |first1=Tim |title=Praxis manned spaceflight log, 1961–2006 |date=2007 |publisher=Springer |location=New York |isbn=978-0387341750 |page=25}}</ref> On 20 February 1962, [[John Glenn]] became the first American in orbit, aboard ''[[Friendship 7]]'' on a [[Atlas LV-3B|Mercury-Atlas rocket]]. The USSR launched five more cosmonauts in Vostok [[space capsule|capsule]]s, including the first woman in space, [[Valentina Tereshkova]], aboard [[Vostok 6]] on 16 June 1963. Through 1963, the US launched a total of two astronauts in suborbital flights and four into orbit. The US also made two [[North American X-15]] flights ([[X-15 Flight 90|90]] and [[X-15 Flight 91|91]], piloted by [[Joseph A. Walker]]), that exceeded the [[Kármán line]], the {{convert|100|km}} altitude used by the [[Fédération Aéronautique Internationale]] (FAI) to denote the edge of space.

In 1961, US President [[John F. Kennedy]] raised the stakes of the Space Race by setting the goal of landing a man on the [[Moon]] and returning him safely to Earth by the end of the 1960s.<ref>{{cite AV media |people=Kennedy, John F. |date=25 May 1961 |title=Special Message to Congress on Urgent National Needs |medium=Motion picture (excerpt) |url=http://www.jfklibrary.org/Asset-Viewer/xzw1gaeeTES6khED14P1Iw.aspx |access-date=1 August 2013 |publisher=John F. Kennedy Presidential Library and Museum |location=Boston, MA |id=Accession Number: TNC:200; Digital Identifier: TNC-200-2}}</ref> That same year, the US began the [[Apollo program]] of launching three-man capsules atop the [[Saturn (rocket family)|Saturn family of launch vehicles]]. In 1962, the US began [[Project Gemini]], which flew 10 missions with two-man crews launched by [[Titan II GLV|Titan II rockets]] in 1965 and 1966. Gemini's objective was to support Apollo by developing American orbital spaceflight experience and techniques to be used during the Moon mission.<ref>{{cite web |last1=Loff  |first1=Sarah  |title=Gemini: Stepping Stone to the Moon |url=http://www.nasa.gov/mission_pages/gemini/#.VKi1GsaWt78 |website=Gemini: Bridge to the Moon |publisher=National Aeronautics and Space Administration |access-date=4 January 2015 |archive-url=https://web.archive.org/web/20141221151510/http://www.nasa.gov/mission_pages/gemini/ |archive-date=21 December 2014 |location=Washington, DC |date=21 October 2013 |url-status=dead |df=dmy-all}}</ref>

Meanwhile, the USSR remained silent about their intentions to send humans to the Moon and proceeded to stretch the limits of their single-pilot Vostok capsule by adapting it to a two or three-person [[Voskhod programme|Voskhod]] capsule to compete with Gemini. They were able to launch two orbital flights in 1964 and 1965 and achieved the first [[spacewalk]], performed by [[Alexei Leonov]] on [[Voskhod 2]], on 8 March 1965. However, the Voskhod did not have Gemini's capability to maneuver in orbit, and the program was terminated. The US Gemini flights did not achieve the first spacewalk, but overcame the early Soviet lead by performing several spacewalks, solving the problem of astronaut fatigue caused by compensating for the lack of gravity, demonstrating the ability of humans to endure two weeks in space, and performing the first [[space rendezvous]] and [[docking and berthing of spacecraft|docking]] of spacecraft.

The US succeeded in developing the [[Saturn V]] rocket necessary to send the Apollo spacecraft to the Moon, and sent [[Frank Borman]], [[Jim Lovell|James Lovell]], and [[William Anders]] into 10 orbits around the Moon in [[Apollo 8]] in December 1968. In 1969, [[Apollo 11]] accomplished Kennedy's goal by landing [[Neil Armstrong]] and [[Buzz Aldrin]] on the Moon on 21 July and returning them safely on 24 July, along with Command Module pilot [[Michael Collins (astronaut)|Michael Collins]]. Through 1972, a total of six Apollo missions landed 12 men to walk on the Moon, half of which drove [[Lunar Roving Vehicle|electric powered vehicles]] on the surface. The crew of [[Apollo 13]]—[[Jim Lovell]], [[Jack Swigert]], and [[Fred Haise]]—survived an in-flight spacecraft failure, they flew by the Moon without landing, and returned safely to Earth.

[[File:Soyuz TMA-7 spacecraft2edit1.jpg|thumb|[[Soyuz spacecraft|Soyuz]], most serial spacecraft]]
[[File:Salyut 1 and Soyuz drawing.png|thumb|[[Salyut 1]], first crewed space station, with docked Soyuz spacecraft]]

During this time, the USSR secretly pursued [[Soviet crewed lunar programs|crewed lunar orbiting and landing programs]]. They successfully developed the three-person [[Soyuz spacecraft]] for use in the lunar programs, but failed to develop the [[N1 (rocket)|N1 rocket]] necessary for a human landing, and discontinued their lunar programs in 1974.<ref>{{cite book|title = Challenge To Apollo The Soviet Union and The Space Race, 1945–1974|last = Siddiqi|first = Asif|page = 832|publisher = NASA|url = https://ntrs.nasa.gov/search.jsp?Ntk=all&Ntx=mode%20matchall&Ntt=SP-2000-4408}}</ref> Upon losing the Moon race they concentrated on the development of [[space station]]s, using the Soyuz as a ferry to take cosmonauts to and from the stations. They started with a series of [[Salyut program|Salyut]] sortie stations from 1971 to 1986.

==== Post-Apollo era ====
[[File:Apollo-Soyuz-Test-Program-artist-rendering.jpg|thumb|Artist's rendering of an [[Apollo CSM]] about to dock with a [[Soyuz spacecraft]]]]

In 1969, Nixon appointed his vice president, [[Spiro Agnew]], to head a Space Task Group to recommend follow-on human spaceflight programs after Apollo. The group proposed an ambitious [[Space Transportation System]] based on a [[Space Shuttle design process|reusable Space Shuttle]], which consisted of a winged, internally fueled orbiter stage burning liquid hydrogen, launched with a similar, but larger [[RP-1|kerosene]]-fueled booster stage, each equipped with airbreathing jet engines for powered return to a runway at the [[Kennedy Space Center]] launch site. Other components of the system included a permanent, modular space station; reusable [[space tug]]; and [[NERVA|nuclear]] interplanetary ferry, leading to a [[human mission to Mars|human expedition to Mars]] as early as 1986 or as late as 2000, depending on the level of funding allocated. However, Nixon knew the American political climate would not support congressional funding for such an ambition, and killed proposals for all but the Shuttle, possibly to be followed by the space station. [[Space Shuttle|Plans for the Shuttle were scaled back]] to reduce development risk, cost, and time, replacing the piloted fly-back booster with two reusable [[Space Shuttle Solid Rocket Booster|solid rocket booster]]s, and the smaller orbiter would use an expendable [[Space Shuttle external tank|external propellant tank]] to feed its hydrogen-fueled [[Space Shuttle main engine|main engine]]s. The orbiter would have to make unpowered landings.

[[File:Space Shuttle Atlantis landing at KSC following STS-122 (crop).jpg|thumb|[[Space Shuttle orbiter]], first crewed orbital spaceplane]]

In 1973, the US launched the [[Skylab]] sortie space station and inhabited it for 171 days with three crews ferried aboard an Apollo spacecraft. During that time, President [[Richard Nixon]] and Soviet general secretary [[Leonid Brezhnev]] were negotiating an easing of Cold War tensions known as [[détente]]. During the détente, they negotiated the [[Apollo–Soyuz]] program, in which an Apollo spacecraft carrying a special docking adapter module would rendezvous and dock with [[Soyuz 19]] in 1975. The American and Soviet crews shook hands in space, but the purpose of the flight was purely symbolic.

The two nations continued to compete rather than cooperate in space, as the US turned to developing the Space Shuttle and planning the space station, which was dubbed ''[[Space Station Freedom|Freedom]]''. The USSR launched three [[Almaz]] military sortie stations from 1973 to 1977, disguised as Salyuts. They followed Salyut with the development of ''[[Mir]]'', the first modular, semi-permanent space station, the construction of which took place from 1986 to 1996. ''Mir'' orbited at an altitude of {{convert|354|km|nmi|abbr=off|sp=us}}, at an [[orbital inclination]] of 51.6°. It was occupied for 4,592 days and made a controlled reentry in 2001.

The Space Shuttle started flying in 1981, but the US Congress failed to approve sufficient funds to make ''Space Station Freedom'' a reality. A fleet of four shuttles was built: ''[[Space Shuttle Columbia|Columbia]]'', ''[[Space Shuttle Challenger|Challenger]]'', ''[[Space Shuttle Discovery|Discovery]]'', and ''[[Space Shuttle Atlantis|Atlantis]]''. A fifth shuttle, ''[[Space Shuttle Endeavour|Endeavour]]'', was built to replace ''Challenger'', which was destroyed in [[Space Shuttle Challenger disaster|an accident during launch]] that killed 7 astronauts on 28 January 1986. From 1983 to 1998, twenty-two Shuttle flights carried components for a [[European Space Agency]] sortie space station called [[Spacelab]] in the Shuttle payload bay.<ref name=StoryShuttle>{{cite book |title=The Story of the Space Shuttle |author=David Michael Harland |publisher=[[Springer Science+Business Media|Springer]] Praxis |date=2004 |page=[https://archive.org/details/storyofspaceshut0000harl/page/444 444] |isbn=978-1-85233-793-3 |author-link=David M. Harland |url=https://archive.org/details/storyofspaceshut0000harl/page/444 }}</ref>

[[File:Buran on An-225 (Le Bourget 1989) (cropped).JPEG|thumb|''[[Buran programme|Buran]]''-class orbiter, Soviet equivalent of the Space Shuttle orbiter]]

The USSR copied the US's reusable [[Space Shuttle orbiter]], which they called ''[[Buran programme|Buran]]''-class orbiter or simply ''Buran'', which was designed to be launched into orbit by the expendable [[Energia (rocket)|Energia]] rocket, and was capable of robotic orbital flight and landing. Unlike the Space Shuttle, ''Buran'' had no main rocket engines, but like the Space Shuttle orbiter, it used smaller rocket engines to perform its final orbital insertion. A single uncrewed orbital test flight took place in November 1988. A second test flight was planned by 1993, but the program was canceled due to lack of funding and the [[dissolution of the Soviet Union]] in 1991. Two more orbiters were never completed, and the one that performed the uncrewed flight was destroyed in a hangar roof collapse in May 2002.

=== US / Russian cooperation ===
[[File:International Space Station after undocking of STS-132.jpg|thumb|right|International Space Station, assembled in orbit by US and Russia]]

The dissolution of the Soviet Union in 1991 brought an end to the Cold War and opened the door to true cooperation between the US and Russia. The Soviet Soyuz and Mir programs were taken over by the Russian Federal Space Agency, which became known as the [[Roscosmos State Corporation]]. The [[Shuttle-Mir Program]] included American Space Shuttles visiting the ''Mir'' space station, Russian cosmonauts flying on the Shuttle, and an American astronaut flying aboard a Soyuz spacecraft for long-duration expeditions aboard ''Mir''.

In 1993, President [[Bill Clinton]] secured Russia's cooperation in converting the planned Space Station ''Freedom'' into the [[International Space Station]] (ISS). Construction of the station began in 1998. The station orbits at an altitude of {{convert|409|km|nmi|sp=us}} and an orbital inclination of 51.65°. Several of the Space Shuttle's 135 orbital flights were to help assemble, supply, and crew the ISS. Russia has built half of the International Space Station and has continued its cooperation with the US.

=== China ===
{{Main|China Manned Space Program}}

[[File:Shenzhou spacecraft assembly.jpg|thumb|right|Chinese [[Shenzhou (spacecraft)|Shenzhou]], first non-USSR and non-USA crewed spacecraft]]
China was the third nation in the world, after the USSR and US, to send humans into space. During the [[Space Race]] between the two superpowers, which culminated with [[Apollo 11]] landing humans on the Moon, [[Mao Zedong]] and [[Zhou Enlai]] decided on 14 July 1967 that China should not be left behind, and initiated their own crewed space program: the top-secret Project 714, which aimed to put two people into space by 1973 with the [[Shuguang spacecraft|Shuguang]] spacecraft. Nineteen [[PLAAF]] pilots were selected for this goal in March 1971. The Shuguang-1 spacecraft, to be launched with the [[CZ-2A]] rocket, was designed to carry a crew of two. The program was officially canceled on 13 May 1972 for economic reasons.

In 1992, under [[China Manned Space Program]] (CMS), also known as "Project 921", authorization and funding was given for the first phase of a third, successful attempt at crewed spaceflight. To achieve independent human spaceflight capability, China developed the [[Shenzhou spacecraft]] and [[Long March 2F]] rocket dedicated to human spaceflight in the next few years, along with critical infrastructures like a new launch site and flight control center being built. The first uncrewed spacecraft, ''[[Shenzhou 1]]'', was launched on 20 November 1999 and recovered the next day, marking the first step of the realization of China's human spaceflight capability. Three more uncrewed missions were conducted in the next few years in order to verify the key technologies. On 15 October 2003 ''[[Shenzhou 5]]'', China's first crewed spaceflight mission, put ''[[Yang Liwei]]'' in orbit for 21 hours and returned safely back to [[Inner Mongolia]], making China the third nation to launch a human into orbit independently.<ref>{{cite web |title=Shenzhou V |url=http://en.cmse.gov.cn/missions/shenzhouv/ |website=China Manned Space |access-date=25 July 2021 |archive-date=17 July 2021 |archive-url=https://web.archive.org/web/20210717205601/http://en.cmse.gov.cn/missions/shenzhouv/ |url-status=dead }}</ref>

The goal of the second phase of CMS was to make technology breakthroughs in [[extravehicular activities]] (EVA, or spacewalk),[[space rendezvous]], and [[Docking and berthing of spacecraft|docking]] to support short-term human activities in space.<ref name="aboutCMS">{{cite web |title=About CMS |url=http://en.cmse.gov.cn/aboutcms/ |website=China Manned Space |access-date=25 July 2021 |archive-date=20 May 2021 |archive-url=https://web.archive.org/web/20210520053620/http://en.cmse.gov.cn/aboutcms/ |url-status=dead }}</ref> On 25 September 2008 during the flight of ''[[Shenzhou 7]]'', ''[[Zhai Zhigang]]'' and ''[[Liu Boming (astronaut)|Liu Boming]]'' completed China's first EVA.<ref>{{cite web |title=Shenzhou VII |url=http://en.cmse.gov.cn/missions/shenzhouvii/ |website=China Manned Space |access-date=25 July 2021 |archive-date=19 January 2022 |archive-url=https://web.archive.org/web/20220119190400/http://en.cmse.gov.cn/missions/shenzhouvii/ |url-status=dead }}</ref> In 2011, China launched the [[Tiangong 1]] target spacecraft and ''[[Shenzhou 8]]'' uncrewed spacecraft. The two spacecraft completed China's first automatic rendezvous and docking on 3 November 2011.<ref>{{cite web |title=Shenzhou VIII |url=http://en.cmse.gov.cn/missions/shenzhouviii/ |website=China Manned Space |access-date=25 July 2021 |archive-date=17 July 2021 |archive-url=https://web.archive.org/web/20210717104932/http://en.cmse.gov.cn/missions/shenzhouviii/ |url-status=dead }}</ref> About 9 months later, ''Tiangong 1'' completed the first manual rendezvous and docking with ''[[Shenzhou 9]]'', which carried China's first female astronaut ''[[Liu Yang (astronaut)|Liu Yang]]''.<ref>{{cite web |title=Shenzhou IX |url=http://en.cmse.gov.cn/missions/shenzhouix/ |website=China Manned Space |access-date=25 July 2021 |archive-date=17 July 2021 |archive-url=https://web.archive.org/web/20210717104930/http://en.cmse.gov.cn/missions/shenzhouix/ |url-status=dead }}</ref>

In September 2016, ''[[Tiangong 2]]'' was launched into orbit. It was a space laboratory with more advanced functions and equipment than ''[[Tiangong 1]]''. A month later, ''[[Shenzhou 11]]'' was launched and docked with ''Tiangong 2''. Two astronauts entered ''Tiangong 2'' and were stationed for about 30 days, verifying the viability of astronauts' medium-term stay in space.<ref name="spacelab">{{cite web |title=Space Laboratory Missions |url=http://en.cmse.gov.cn/missions/space_laboratory_missions/ |website=China Manned Space |access-date=25 July 2021}}</ref> In April 2017, China's first cargo spacecraft, ''[[Tianzhou 1]]'' docked with ''Tiangong 2'' and completed multiple in-orbit propellant refueling tests, which marked the successful completion of the second phase of CMS.<ref name="spacelab"/>

The third phase of CMS began in 2020. The goal of this phase is to build China's own space station, [[Tiangong Space Station|''Tiangong'']].<ref>{{cite web |title=China launches new Long March-5B rocket for space station program |url=http://en.cmse.gov.cn/news/202005/t20200506_46488.html |website=China Manned Space |access-date=26 July 2021 |archive-url=https://web.archive.org/web/20210617054112/http://en.cmse.gov.cn/news/202005/t20200506_46488.html |archive-date=17 June 2021 |date=5 May 2020}}</ref> The first module of ''Tiangong'', the [[Tianhe core module]], was launched into orbit by China's most powerful rocket [[Long March 5B]] on 29 April 2021.<ref name="third step">{{cite web |title=Core Module Tianhe Launch a Complete Success – Construction of China Space Station in Full Swing |url=http://en.cmse.gov.cn/news/202105/t20210528_48002.html |website=China Manned Space |access-date=26 July 2021 |date=30 April 2021}}</ref> It was later visited by multiple cargo and crewed spacecraft and demonstrated China's capability of sustaining Chinese astronauts' long-term stay in space.

According to CMS announcement, all missions of Tiangong Space Station are scheduled to be carried out by the end of 2022.<ref name="CSSplan">{{cite web |title=空间站天和核心舱飞行任务新闻发布会召开 |url=http://www.cmse.gov.cn/ztbd/xwfbh/202106/t20210622_48281.html |website=China Manned Space |access-date=2021-07-13 |archive-url=https://web.archive.org/web/20210713065620/http://www.cmse.gov.cn/ztbd/xwfbh/202106/t20210622_48281.html |archive-date=2021-07-13 |date=2021-04-29 |url-status=live |language=zh}}</ref> Once the construction is completed, ''Tiangong'' will enter the application and development phase, which is poised to last for no less than 10 years.<ref name="CSSplan"/>

=== Abandoned programs of other nations ===
The [[European Space Agency]] began development of the [[Hermes (spacecraft)|Hermes]] shuttle [[spaceplane]] in 1987, to be launched on the [[Ariane 5]] expendable launch vehicle. It was intended to dock with the European [[Columbus Man-Tended Free Flyer|Columbus space station]]. The projects were canceled in 1992 when it became clear that neither cost nor performance goals could be achieved. No Hermes shuttles were ever built. The Columbus space station was reconfigured as the [[Columbus (ISS module)|European module of the same name]] on the International Space Station.<ref>{{cite web |title=Columbus laboratory |url=https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Columbus/Columbus_laboratory |website=www.esa.int |publisher=The European Space Agency |access-date=26 October 2022 |language=en}}</ref>

Japan ([[NASDA]]) began the development of the [[HOPE-X]] experimental shuttle spaceplane in the 1980s, to be launched on its [[H-IIA]] expendable launch vehicle. A string of failures in 1998 led to funding reductions, and the project's cancellation in 2003 in favor of participation in the International Space Station program through the [[Kibo (ISS module)|''Kibō'' Japanese Experiment Module]] and [[H-II Transfer Vehicle]] cargo spacecraft. As an alternative to HOPE-X, NASDA in 2001 proposed the [[Fuji (spacecraft)|Fuji crew capsule]] for independent or ISS flights, but the project did not proceed to the contracting stage.{{Citation needed|date=November 2020}}

From 1993 to 1997, the {{Interlanguage link|Japanese Rocket Society|ja|3=日本ロケット協会|vertical-align=sup}}, [[Kawasaki Heavy Industries]], and [[Mitsubishi Heavy Industries]] worked on the proposed [[Kankoh-maru]] [[vertical takeoff and landing|vertical-takeoff-and-landing]] [[single-stage-to-orbit]] reusable launch system. In 2005, this system was proposed for space tourism.<ref>{{Cite web |last=Magazin |first=Sia |date=2022-12-02 |title=Kankoh-maru Japan's Space Tourism Single Stage Reusable Rocket |url=https://siamagazin.com/kankoh-maru-japans-space-tourism-single-stage-reusable-rocket/ |access-date=2023-10-17 |website=Sia Magazin |language=en-US}}</ref>

According to a press release from the [[Iraqi News Agency]] dated 5 December 1989, there was only one test of the [[Al-Abid]] space launcher, which [[Iraq]] intended to use to develop its own crewed space facilities by the end of the century. These plans were put to an end by the [[Gulf War]] of 1991 and the economic hardships that followed.{{Citation needed|date=November 2020}}

=== United States "Shuttle gap" ===
[[File:STS-135 begins takeoff (cropped).jpg|thumb|[[STS-135]] (July 2011), the final human spaceflight of the United States until 2018]]
[[File:Virgin Galactic SpaceShipTwo "Unity" rollout 19Feb2016, FAITH hangar, Mojave, California.jpg|alt=|thumb|[[VSS Unity|VSS ''Unity'']] [[VSS Unity VP-03|Flight VP-03]] December 2018, the first human spaceflight from the United States since [[STS-135]] ]]

Under the George W. Bush administration, the [[Constellation program]] included plans for retiring the Space Shuttle program and replacing it with the capability for spaceflight beyond low Earth orbit. In the [[2011 United States federal budget]], the Obama administration canceled Constellation for being over budget and behind schedule, while not innovating and investing in critical new technologies.<ref>[http://blogs.orlandosentinel.com/news_space_thewritestuff/2008/11/congressional-w.html Congressional watchdog finds NASA's new rocket is in trouble] {{webarchive|url=https://web.archive.org/web/20111129102151/http://blogs.orlandosentinel.com/news_space_thewritestuff/2008/11/congressional-w.html |date=29 November 2011 }}. Orlando Sentinel blog summary of official reports. 3 November 2008</ref> As part of the [[Artemis program]], NASA is developing the [[Orion (spacecraft)|Orion]] spacecraft to be launched by the [[Space Launch System]]. Under the [[Commercial Crew Development]] plan, NASA relies on transportation services provided by the private sector to reach low Earth orbit, such as [[SpaceX Dragon 2]], the [[Boeing Starliner]] or [[Sierra Nevada Corporation]]'s [[Dream Chaser]]. The period between the retirement of the Space Shuttle in 2011 and the first launch into space of [[SpaceShipTwo]] [[VSS Unity VP-03|Flight VP-03]] on 13 December 2018 is similar to the gap between the end of [[Apollo program|Apollo]] in 1975 and the [[STS-1|first Space Shuttle flight]] in 1981, and is referred to by a presidential Blue Ribbon Committee as the U.S. human spaceflight gap.

=== Commercial private spaceflight ===
{{Update section|date=September 2024}}
[[File:SpaceShipOne Flight 15P photo D Ramey Logan.jpg|thumb|[[SpaceShipOne]], first private sub-orbital spaceplane]]
[[File:Crew Dragon at the ISS for Demo Mission 1 (cropped).jpg|thumb|right|[[Crew Dragon]], first private orbital spacecraft]]

Since the early 2000s, a variety of [[private spaceflight]] ventures have been undertaken. {{As of|2024|November|post=,}} [[SpaceX]]<ref>{{Cite web |title=SpaceX's Historic Demo-2 Crew Dragon Astronaut Test Flight: Full Coverage |url=https://www.space.com/spacex-crew-dragon-demo-2-test-flight-explained.html |last=Wall |first=Mike |date=2 August 2020 |url-status=live |archive-url=https://web.archive.org/web/20241007113205/https://www.space.com/spacex-crew-dragon-demo-2-test-flight-explained.html |archive-date=7 October 2024 |access-date=14 November 2024 |website=[[Space.com]]}}</ref> and [[Boeing]]<ref>{{Cite web |title=NASA's Boeing Crew Flight Test |url=https://www.nasa.gov/mission/boeing-crewflighttest/ |url-status=live |archive-url=https://web.archive.org/web/20240916042346/https://www.nasa.gov/mission/boeing-crewflighttest/ |archive-date=16 September 2024 |access-date=14 November 2024 |website=Nasa.gov}}</ref> have launched humans to orbit,{{NoteTag|Both missions were to the [[International Space Station]].}} while [[Blue Origin]] has launched 8 crewed flights, six of which crossed the [[Kármán line]].<ref>{{Cite web |title='One of the Cleanest Flights I've Seen.' Blue Origin Launches 6 People to Space, Lands Safely on NS-26 Flight (Video) |url=https://www.space.com/blue-origin-ns-26-suborbital-space-tourism-launch |last=Wall |first=Mike |date=29 August 2024 |url-status=live |archive-url=https://web.archive.org/web/20241007101912/https://www.space.com/blue-origin-ns-26-suborbital-space-tourism-launch |archive-date=7 October 2024 |access-date=14 November 2024 |website=[[Space.com]]}}</ref>{{NoteTag|There is no internationally recognized definition for the boundary of space; although the Kármán line ({{convert|100|km}}) is commonly used, distances ranging from {{convert|30|km}} to {{convert|1600000|km}} have been proposed.<ref>{{Cite web |title=The Kármán Line: Where Space Begins |url=https://www.astronomy.com/space-exploration/the-karman-line-where-does-space-begin/ |last=Betz |first=Eric |date=27 November 2023 |url-status=live |archive-url=https://web.archive.org/web/20241109091125/https://www.astronomy.com/web/20241109091125/https://www.astronomy.com/space-exploration/the-karman-line-where-does-space-begin/ |archive-date=9 November 2024 |access-date=14 November 2024 |website=[[Astronomy (magazine)|Astronomy]]}}</ref>}} [[Virgin Galactic]] has launched crew to a height above {{cvt|80|km}} on a suborbital trajectory.<ref name="spaceshiptwoflight">{{cite web |last=Malik |first= Tariq |title=Virgin Galactic's 4th Powered Test Flight of SpaceShipTwo Unity in Twitter Posts |url=https://www.space.com/42725-virgin-galactic-spaceshiptwo-unity-4th-powered-flight-twitter-updates.html |date=13 December 2018 |archive-url=https://web.archive.org/web/20210427085514/https://www.space.com/42725-virgin-galactic-spaceshiptwo-unity-4th-powered-flight-twitter-updates.html |archive-date=27 April 2021 |website=[[Space.com]] |access-date=13 May 2021}}</ref> Several other companies, including [[Sierra Nevada Corporation|Sierra Nevada]] and [[Copenhagen Suborbitals]], have developed crewed spacecraft.<ref>{{Cite web |title=Sierra Space Working with NASA on Crewed Dream Chaser |url=https://spaceref.com/newspace-and-tech/sierra-space-working-with-nasa-on-crewed-dream-chaser/ |last=Messier |first=Douglas |date=7 September 2023 |access-date=14 November 2024 |website=SpaceRef}}</ref><ref>{{Cite web |title=Spica |url=https://copenhagensuborbitals.com/missions/spica/ |archive-url=https://web.archive.org/web/20241002180846/https://copenhagensuborbitals.com/missions/spica/ |archive-date=2024-10-02 |access-date=2024-11-14 |website=[[Copenhagen Suborbitals]]}}</ref> SpaceX, Boeing, Blue Origin, and Virgin Galactic plan to fly commercial passengers in the emerging [[space tourism]] market.<ref name="CNBC Space Tourism">{{cite web |last1=Sheetz |first1=Michael |title=Investing in Space How SpaceX, Virgin Galactic, Blue Origin and others compete in the growing space tourism market |url=https://www.cnbc.com/2020/09/26/space-tourism-how-spacex-virgin-galactic-blue-origin-axiom-compete.html |website=CNBC |date=26 September 2020 |access-date=4 January 2025}}</ref>

[[SpaceX]] has developed [[Crew Dragon]] flying on [[Falcon 9]]. It first launched astronauts to orbit and to the ISS in May 2020 as part of the [[Crew Dragon Demo-2|Demo-2]] mission. Developed as part of NASA's [[Commercial Crew Development]] program, the capsule is also available for flights with other customers. A first tourist mission, [[Inspiration4]], launched in September 2021.<ref name=Inspiration4>{{cite web |last1=Atkinson |first1=Ian |title=SpaceX launches Inspiration4, first all-private orbital mission |url=https://www.nasaspaceflight.com/2021/09/spacex-launch-inspiration4/ |website=NASASpaceflight.com |date=15 September 2021 |access-date=16 September 2021}}</ref>

[[Boeing Defense, Space & Security|Boeing]] developed the [[Boeing Starliner|Starliner]] capsule as part of NASA's Commercial Crew Development program, which is launched on a [[United Launch Alliance]] [[Atlas V]] launch vehicle.<ref name=nasaAnnounce20140906>{{cite web |title=American Companies Selected to Return Astronaut Launches to American Soil |last=Bolden |first=Charlie |url=http://blogs.nasa.gov/bolden/2014/09/16/american-companies-selected-to-return-astronaut-launches-to-american-soil/ |website=NASA.gov |date=16 September 2014 |access-date=16 September 2014}}</ref> Starliner made an uncrewed flight in December 2019. A second uncrewed flight attempt was launched in May 2022.<ref>{{cite web |last1=Clark |first1=Stephen |title=NASA official says Starliner demo mission not likely to launch until next year |url=https://spaceflightnow.com/2021/09/22/nasa-official-says-starliner-demo-mission-not-likely-to-launch-until-next-year/ |website=Spaceflight Now |access-date=23 September 2021}}</ref> A crewed flight to fully certify Starliner was launched in June 2024.<ref>{{cite web |last1=Berger |first1=Eric |title=Boeing to ground Starliner indefinitely until valve issue solved |url=https://arstechnica.com/science/2021/08/boeing-to-ground-starliner-indefinitely-until-valve-issue-solved/ |website=Ars Technica |date=13 August 2021 |access-date=16 September 2021}}</ref> Similar to SpaceX, development funding has been provided by a mix of [[government funding|government]] and [[private capital|private]] funds.<ref name=sn20140921>{{cite news |last1=Foust|first1=Jeff |title=NASA Commercial Crew Awards Leave Unanswered Questions |url=http://www.spacenews.com/article/civil-space/41924nasa-commercial-crew-awards-leave-unanswered-questions |archive-url=https://archive.today/20140921132432/http://www.spacenews.com/article/civil-space/41924nasa-commercial-crew-awards-leave-unanswered-questions |url-status=dead |archive-date=21 September 2014 |access-date=21 September 2014 |work=Space News |date=19 September 2014 |quote="We basically awarded based on the proposals that we were given", Kathy Lueders, NASA commercial crew program manager, said in a teleconference with reporters after the announcement. "Both contracts have the same requirements. The companies proposed the value within which they were able to do the work, and the government accepted that".}}</ref><ref name=NASApress20140916>{{cite web |title=Release 14-256 NASA Chooses American Companies to Transport U.S. Astronauts to International Space Station |url=http://www.nasa.gov/press/2014/september/nasa-chooses-american-companies-to-transport-us-astronauts-to-international |website=www.nasa.gov |publisher=NASA |access-date=29 October 2014}}</ref>

[[Virgin Galactic]] is developing [[SpaceshipTwo]], a commercial [[suborbital spaceflight|suborbital]] spacecraft aimed at the [[space tourism]] market. It reached space in December 2018.<ref name="spaceshiptwoflight"/>

[[Blue Origin]] is in a multi-year [[flight test|test]] program of their [[New Shepard]] vehicle and has carried out [[New Shepard#Flight list|thirty one launches]] as of May 2025, including twenty uncrewed test flights and eleven crewed flights. The first crewed flight, carrying founder [[Jeff Bezos]], his brother [[Mark Bezos]], aviator [[Wally Funk]], and 18-year old [[Oliver Daemen]] launched on July 20, 2021.<ref>{{Cite web |last=Wattles |first=Jackie |last2=Sangal |first2=Aditi |last3=Macaya |first3=Melissa |last4=Mahtani |first4=Melissa |last5=Wagner |first5=Meg |last6=Vogt |first6=Adrienne |date=2021-07-20 |title=Jeff Bezos goes to space: Live updates {{!}} CNN Business |url=https://edition.cnn.com/business/live-news/jeff-bezos-space-flight-07-20-21 |access-date=2025-05-10 |website=CNN |language=en}}</ref>