Human presence in space (also anthropogenic presence in space or humanity in space) is the direct and mediated presence or

telepresence Telepresence is the appearance or sensation of a person being present at a place other than their true location, via telerobotics or video. Telepresence requires that the users' senses interact with specific stimuli in order to provide the feeli ...

of humans in outer space, and in an extended sense across space including astronomical bodies. Human presence in space, particularly through mediation, can take many physical forms from

space debris Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include dere ...

uncrewed spacecraft Uncrewed spacecraft or robotic spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input, such as remote control, or remote guidance. They may also be autonomous, in which th ...

, artificial satellites, space observatories,

crewed spacecraft This is a list of all crewed spacecraft types that have flown into space, including sub-orbital flights above 80 km, space stations that have been visited by at least one crew member, and spacecraft currently planned to operate with crews ...

, art in space, to

human outpost Human outposts

s in outer space such as

space station A space station (or orbital station) is a spacecraft which remains orbital spaceflight, in orbit and human spaceflight, hosts humans for extended periods of time. It therefore is an artificial satellite featuring space habitat (facility), habitat ...

s. While human presence in space, particularly its continuation and permanence can be a goal in itself, human presence can have a range of purposes and modes from

space exploration Space exploration is the process of utilizing astronomy and space technology to investigate outer space. While the exploration of space is currently carried out mainly by astronomers with telescopes, its physical exploration is conducted bo ...

commercial use of space Space economy refers to the set of activities, industries, technologies, services, and resources that generate economic value through the space exploration, understanding, management, and exploitation of outer space. Commercial satellite us ...

extraterrestrial settlement Extraterrestrial settlement can be any type of permanent habitation outside of Earth, beyond its space boundary, such as: * Space settlement ** Orbital space station **Cycler **Interstellar ark ***Generation ship * Extraterrestrial surface settle ...

or even

space colonization Space colonization (or extraterrestrial colonization) is the human settlement, settlement or colonization of outer space and astronomical bodies. The concept in its broad sense has been applied to any permanent human presence in space, such ...

and

militarisation of space The militarisation of space involved the placement and development of weaponry and military technology in outer space. The early exploration of space in the mid-20th century had, in part, a military motivation, as the United States and the Sov ...

. Human presence in space is realized and sustained through the advancement and application of

space science Space is a three-dimensional continuum containing positions and directions. In classical physics, physical space is often conceived in three linear dimensions. Modern physicists usually consider it, with time, to be part of a boundless ...

s, particularly

astronautics Astronautics (or cosmonautics) is the practice of sending spacecraft beyond atmosphere of Earth, Earth's atmosphere into outer space. Spaceflight is one of its main applications and space science is its overarching field. The term ''astronautics' ...

in the form of spaceflight and

space infrastructure Human presence in space (also anthropogenic presence in space or humanity in space) is the direct and mediated presence or telepresence of humans in outer space, and in an extended sense across space including astronomical body, astronomical ...

. Humans have achieved some mediated presence throughout the

Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...

, but the most extensive presence has been in orbit around Earth. Humans reached outer space mediated in 1944 (

MW 18014 MW 18014 was a German A-4 test rocket launched on 20 June 1944, at the Peenemünde Army Research Center in Peenemünde. It was the first man-made object to reach outer space, attaining an apogee of , well above the Kármán line that was estab ...

) and have sustained mediated presence since 1958 (

Vanguard 1 Vanguard 1 (Harvard designation: 1958-Beta 2, COSPAR ID: 1958-002B ) is an American satellite that was the fourth artificial Earth-orbiting satellite to be successfully launched, following Sputnik 1 Sputnik 1 (, , ''Satellite 1''), ...

), as well as having reached space directly for the first time on 12 April 1961 (

Yuri Gagarin Yuri Alekseyevich Gagarin; Gagarin's first name is sometimes transliterated as ''Yuriy'', ''Youri'', or ''Yury''. (9 March 1934 – 27 March 1968) was a Soviet pilot and cosmonaut who, aboard the first successful Human spaceflight, crewed sp ...

) and continuously since the year 2000 with the crewed

International Space Station The International Space Station (ISS) is a large space station that was Assembly of the International Space Station, assembled and is maintained in low Earth orbit by a collaboration of five space agencies and their contractors: NASA (United ...

(ISS), or since the later 1980s with some few interruptions through crewing its predecessor, the space station

Mir ''Mir'' (, ; ) was a space station operated in low Earth orbit from 1986 to 2001, first by the Soviet Union and later by the Russia, Russian Federation. ''Mir'' was the first modular space station and was assembled in orbit from 1986 to ...

. The increasing and extensive human presence in orbital space around Earth, beside its benefits, has also produced a threat to it by carrying with it space debris, potentially cascading into the so-called

Kessler syndrome The Kessler syndrome, also known as the Kessler effect, collisional cascading, or ablation cascade, is a scenario proposed by NASA scientists Donald J. Kessler and Burton G. Cour-Palais in 1978. It describes a situation in which the density of o ...

. This has raised the need for regulation and mitigation of such to secure a sustainable access to outer space. Securing the access to space and human presence in space has been pursued and allowed by the establishment of

space law Space law is the body of law governing space-related activities, encompassing both international and domestic agreements, rules, and principles. Parameters of space law include space exploration, liability for damage, weapons use, rescue efforts ...

and

space industry Space industry refers to economic activities related to manufacturing components that go into outer space (Earth's orbit or beyond), delivering them to those regions, and related services. Owing to the prominence of satellite-related activiti ...

, creating a

. But sustainability has remained a challenging goal, with the

United Nations The United Nations (UN) is the Earth, global intergovernmental organization established by the signing of the Charter of the United Nations, UN Charter on 26 June 1945 with the stated purpose of maintaining international peace and internationa ...

seeing the need to advance long-term sustainability of outer space activities in space science and application, and the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

having it as a crucial goal of its contemporary

space policy Space policy is the political decision-making process for, and application of, public policy of a state (or association of states) regarding spaceflight and uses of outer space, both for civilian (scientific and commercial) and military purposes ...

and

space program A space program is an organized effort by a government or a company with a goal related to outer space. Lists of space programs include: * List of government space agencies * List of private spaceflight companies * List of human spaceflight prog ...

Terminology

For outer space being the dominant expanse of

space Space is a three-dimensional continuum containing positions and directions. In classical physics, physical space is often conceived in three linear dimensions. Modern physicists usually consider it, with time, to be part of a boundless ...

, "space" is often used synonymously for outer space, referring to human presence in space to human presence across all of space, including astronomical bodies which outer space surrounds. The United States has been using the term "''human presence''" to identify one of the long-term goals of its space program and its international cooperation. While it traditionally means and is used to name direct human presence, it is also used for mediated presence. Differentiating human presence in space between direct and mediated human presence, meaning human or non-human presence, such as with crewed or uncrewed spacecraft, is rooted in a history of how human presence is to be understood (see dedicated chapter). Human, particularly direct, presence in space is sometimes replaced with "boots on the ground" or equated with space colonization. But such terms, particularly

colonization 475px, Map of the year each country achieved List of sovereign states by date of formation, independence. Colonization (British English: colonisation) is a process of establishing occupation of or control over foreign territories or peoples f ...

and even settlement has been avoided and questioned to describe human presence in space, since they employ very particular concepts of appropriation, with historic baggage, addressing the forms of human presence in a particular and not general way. Alternatively some have used the term "''humanization of space''", which differs in focusing on the general development, impact and structure of human presence in space. On an international level the United Nations uses the phrase of "''outer space activity''" for the activity of its member states in space.

History

Human presence in outer space began with the first launches of artificial object in the mid 20th century, and has increased to the point where Earth is orbited by a vast number of artificial objects and the far reaches of the Solar System have been visited and explored by a range of space probes. Human presence throughout the Solar System is continued by different contemporary and future missions, most of them mediating human presence through robotic spaceflight. First a realized project of the

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

and followed in competition by the

, human presence in space is now an increasingly international and commercial field.

Representation, participation and regulation

Participation and representation of humanity in space is an issue of human access to and presence in space ever since the beginning of spaceflight. Different space agencies,

s and interest groups such as the

International Astronomical Union The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...

have been formed supporting or producing humanity's or a particular human presence in space. Representation has been shaped by the inclusiveness, scope and varying capabilities of these organizations and programs. Some rights of non-spacefaring countries to partake in spaceflight have been secured through international

, declaring space the " province of all mankind", understanding spaceflight as its resource, though sharing of space for all humanity is still criticized as

imperialist Imperialism is the maintaining and extending of power over foreign nations, particularly through expansionism, employing both hard power (military and economic power) and soft power ( diplomatic power and cultural imperialism). Imperialism fo ...

and lacking, particularly regarding regulation of private spceflight. Additionally to international inclusion the inclusion of women,

people of colour The term "person of color" (: people of color or persons of color; abbreviated POC) is used to describe any person who is not considered "white". In its current meaning, the term originated in, and is associated with, the United States. From th ...

and with

disability Disability is the experience of any condition that makes it more difficult for a person to do certain activities or have equitable access within a given society. Disabilities may be Cognitive disability, cognitive, Developmental disability, d ...

has also been lacking. To reach a more inclusive spaceflight some organizations like the ''Justspace Alliance'' and

IAU The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...

featured ''Inclusive Astronomy'' have been formed in recent years.

Law and governance

Space activity is legally based on the

Outer Space Treaty The Outer Space Treaty, formally the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, is a Multilateralism, multilateral treaty that forms the bas ...

, the main international treaty. Though there are other international agreements such as the significantly less ratified

Moon Treaty The Agreement Governing the Activities of States on the Moon and Other Celestial Bodies, The development of international space law has revolved much around outer space being defined as ''common heritage of mankind''. The ''Magna Carta of Space'' presented by William A. Hyman in 1966 framed outer space explicitly not as ''

terra nullius ''Terra nullius'' (, plural ''terrae nullius'') is a Latin expression meaning " nobody's land". Since the nineteenth century it has occasionally been used in international law as a principle to justify claims that territory may be acquired ...

'' but as ''

res communis ''Res communis'' is a concept or doctrine. The expression is a Latin language, Latin term derived from Roman law that preceded today's concepts of the commons and common heritage of mankind. It has relevance in international law and common law. I ...

'', which subsequently influenced the work of the

United Nations Committee on the Peaceful Uses of Outer Space The United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) is a United Nations committee whose main task is to review and foster international cooperation in the peaceful uses of outer space, as well as to consider legal issues a ...

(COPUOS). The

United Nations Office for Outer Space Affairs The United Nations Office for Outer Space Affairs (UNOOSA) is an office of the U.N. Secretariat that promotes and facilitates peaceful international cooperation in outer space. It works to establish or strengthen the legal and regulatory fram ...

and the

International Telecommunication Union The International Telecommunication Union (ITU)In the other common languages of the ITU: * * is a list of specialized agencies of the United Nations, specialized agency of the United Nations responsible for many matters related to information ...

are international organizations central for facilitating space regulation, such as space traffic management.

Forms

Signals and radiation

Humans have been producing a range of

radiation In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. This includes: * ''electromagnetic radiation'' consisting of photons, such as radio waves, microwaves, infr ...

which has reached space unintentionally as well as intentionally, well before any direct human presence in space.

Electromagnetic radiation In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength ...

such as light, of humans, has been reaching even stars as far away as the age of the radiation. Beginning in the 20th century, humans have been sending radiation significantly into space.

Nuclear explosion A nuclear explosion is an explosion that occurs as a result of the rapid release of energy from a high-speed nuclear reaction. The driving reaction may be nuclear fission or nuclear fusion or a multi-stage cascading combination of the two, th ...

s, especially high-altitude ones have since at times, starting with 1958, just a year after the first satellite Sputnik was launched, introduced strong and broad radiation from humans into space, producing

electromagnetic pulse An electromagnetic pulse (EMP), also referred to as a transient electromagnetic disturbance (TED), is a brief burst of electromagnetic energy. The origin of an EMP can be natural or artificial, and can occur as an electromagnetic field, as an ...

s and orbital radiation belts, adding to the explosion's destructive potential on ground and in orbit. While Earth's and humanities radiation profile is the main material for space based remote Earth observation, but radiation by human activity from Earth and from space has also been an obstacle for human activities, such as spiritual life or

astronomy Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest includ ...

through

light pollution Light pollution is the presence of any unwanted, inappropriate, or excessive artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting sources, during the ...

and

radio spectrum pollution Radio spectrum pollution is the straying of waves in the radio and electromagnetic spectrums outside their allocations that cause problems for some activities. It is of particular concern to radio astronomers. Radio spectrum pollution is miti ...

from Earth and space. In the case of

radio astronomy Radio astronomy is a subfield of astronomy that studies Astronomical object, celestial objects using radio waves. It started in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming from the Milky Way. Subsequent observat ...

radio quiet zone A radio quiet zone is an area where radio transmissions are restricted in order to protect a radio telescope or a communications station from radio frequency interference. The Radio Regulations of the International Telecommunication Union (ITU) d ...

s have been kept and sought out, with the

far side of the Moon The far side of the Moon is the hemisphere of the Moon that is facing away from Earth, the opposite hemisphere is the near side. It always has the same surface oriented away from Earth because of synchronous rotation in the Moon's orbit. C ...

being most pristine facing away from human made electromagnetic interference.

Space junk and human impact

Space junk as product and form of human presence in space has existed ever since the first orbital spaceflights and comes mostly in the form of space debris in outer space. Space debris has been for example possibly the first human objects to have been present in space beyond Earth, reaching its

escape velocity In celestial mechanics, escape velocity or escape speed is the minimum speed needed for an object to escape from contact with or orbit of a primary body, assuming: * Ballistic trajectory – no other forces are acting on the object, such as ...

after being ejected purposefully from an exploded

Aerobee The Aerobee rocket was one of the United States' most produced and productive sounding rockets. Developed by the Aerojet Corporation, the Aerobee was designed to combine the altitude and launching capability of the V-2 with the cost effectiven ...

rocket in 1957. Most space debris is in orbit around Earth, it can stay there for years to centuries if at altitudes from hundreds to thousands of kilometers, before it falls to Earth. Space debris is a hazard since it can hit and damage spacecraft. Having reached considerable amounts around Earth, policies have been put into place to prevent space debris and hazards, such as international regulation to prevent nuclear hazards in Earth's orbit and the

Registration Convention The Convention on Registration of Objects Launched into Outer Space (commonly known as the Registration Convention) was adopted by the United Nations General Assembly in 1974 and went into force in 1976. As of February 2022, it has been ratified ...

as part of space traffic management. But space junk can also come as result of human activity on astronomical bodies, such as the remains of space missions, like the many artificial objects left behind on the Moon, and on other bodies. ALSEP AS17-134-20500

Robotic

Human presence in space has been strongly based on the many

robotic spacecraft Uncrewed spacecraft or robotic spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input, such as remote control, or remote guidance. They may also be autonomous, in which t ...

, particularly as the many

artificial satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scienti ...

s in orbit around Earth. Many firsts of human presence in space have been achieved by robotic missions. The first artificial object to reach space, above the 100 km altitude

Kármán line The Kármán line (or von Kármán line ) is a conventional definition of the Outer space#Boundary, edge of space; it is widely but not universally accepted. The international record-keeping body Fédération Aéronautique Internationale, FAI ( ...

, and therefore performing the first sub-orbital flight was

in 1944. But the first sustained presence in space was established by the

orbital flight An orbital spaceflight (or orbital flight) is a spaceflight in which a spacecraft is placed on a trajectory where it could remain in space for at least one orbit. To do this around the Earth, it must be on a free trajectory which has an altitud ...

Sputnik Sputnik 1 (, , ''Satellite 1''), sometimes referred to as simply Sputnik, was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space progra ...

in 1957. Followed by a rich number of robotic

space probe Uncrewed spacecraft or robotic spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input, such as remote control, or remote guidance. They may also be autonomous, in which th ...

s achieving human presence and exploration throughout the Solar system for the first time. Human presence at the Moon was established by the

Luna programme The Luna programme (from the Russian word "Moon, Luna" meaning "Moon"), occasionally called ''Lunik'' by western media, was a series of robotic spacecraft missions sent to the Moon by the Soviet Union between 1959 and 1976. The programme acc ...

starting in 1959, with a first flyby and

heliocentric orbit A heliocentric orbit (also called circumsolar orbit) is an orbit around the barycenter of the Solar System, which is usually located within or very near the surface of the Sun. All planets, comets, and asteroids in the Solar System, and the Sun ...

(

Luna 1 ''Luna 1'', also known as ''Mechta'' ( , ''Literal translation, lit.'': ''Dream''), ''E-1 No.4'' and ''First Lunar Rover'', was the first spacecraft to reach the vicinity of Earth's Moon, the first spacecraft to leave Earth's orbit, and the fi ...

), a first arrival of an artificial object on the surface with an impactor (

Luna 2 ''Luna 2'' (), originally named the Second Soviet Cosmic Rocket and nicknamed Lunik 2 in contemporaneous media, was the sixth of the Soviet Union's Luna programme spacecraft launched to the Moon, E-1 No.7. It was the first spacecraft Moon landi ...

), and a for the first time a successful flight to the

(

Luna 3 Luna 3, or E-2A No.1 (), was a Soviet spacecraft launched in 1959 as part of the Luna programme. It was the first mission to photograph the far side of the Moon and the third Soviet space probe to be sent to the neighborhood of the Moon. The hi ...

). The Moon then was in 1966 visited for the first time by a lander (

Luna 9 Luna 9 (Луна-9), internal designation Ye-6 No.13, was an uncrewed space mission of the Soviet Union's Luna programme. On 3 February 1966, the Luna 9 spacecraft became the first spacecraft to achieve a soft landing on the Moon and return ima ...

), as well as an

orbiter A spacecraft is a vehicle that is designed to fly and operate in outer space. Spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, ...

(

Luna 10 Luna 10 (or Lunik 10) was a 1966 Soviet lunar robotic spacecraft mission in the Luna program. It was the first artificial satellite of the Moon, and any other body other than Earth and the Sun (in heliocentric orbit). Luna 10 conducted extens ...

), and in 1970 for the first time a

rover Rover may refer to: People Name * Constance Rover (1910–2005), English historian * Jolanda de Rover (born 1963), Dutch swimmer * Rover Thomas (c. 1920–1998), Indigenous Australian artist Stage name * Rover (musician), French singer-songw ...

(

Lunokhod 1 ''Lunokhod 1'' (Russian language, Russian: Луноход-1 "Moonwalker 1"), also known as Аппарат 8ЕЛ № 203 ("Device 8EL No. 203") was the first rover (space exploration), robotic rover lunar rover, on the Moon and the first to freel ...

) landed on an extraterrestrial body. Interplanetary presence was established at Venus by the

Venera program The Venera (, 'Venus') program was a series of space probes developed by the Soviet Union between 1961 and 1984 to gather information about the planet Venus. Thirteen probes successfully entered the Venusian atmosphere, including the two ...

, with a flyby in 1961 (Venera 1) and a crash in 1966 (Venera 3). Presence in the

outer Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sol ...

was achieved by ''

Pioneer 10 ''Pioneer 10'' (originally designated Pioneer F) is a NASA space probe launched in 1972 that completed the first mission to the planet Jupiter. ''Pioneer 10'' became the first of five artificial objects to achieve the escape velocity needed ...

'' in 1972 and presence in interstellar space by ''

Voyager 1 ''Voyager 1'' is a space probe launched by NASA on September 5, 1977, as part of the Voyager program to study the outer Solar System and the interstellar medium, interstellar space beyond the Sun's heliosphere. It was launched 16 days afte ...

'' in 2012. The 1958

is the fourth artificial satellite and the oldest spacecraft still in space and orbit around Earth, though inactive.

Presence of non-human life from Earth

Since the very beginning of human outer space activities in 1944, and possibly before that, life has been present with microscopic life as space contaminate and after 1960 as space research subjects. Prior to crewed spaceflight non-human animals had been subjects of space research, specifically

bioastronautics Bioastronautics is a specialty area of biological and astronautical research which encompasses numerous aspects of biological, behavioral, and medical concern governing humans and other living organisms in outer space; and includes the design o ...

and

astrobiology Astrobiology (also xenology or exobiology) is a scientific field within the List of life sciences, life and environmental sciences that studies the abiogenesis, origins, Protocell, early evolution, distribution, and future of life in the univ ...

, being exposed to ever higher testflights. The first animals (including humans) and plant seeds in space above the 100 km

were

corn Maize (; ''Zea mays''), also known as corn in North American English, is a tall stout Poaceae, grass that produces cereal grain. It was domesticated by indigenous peoples of Mexico, indigenous peoples in southern Mexico about 9,000 years ago ...

seeds and fruit flies, launched for the first time on 9 July 1946, with the first fruit flies launched and returned alive in 1947. In 1949 Albert II, became the first

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

and first primate reaching the 100 km Kármán line, and in 1957 the dog

Laika Laika ( ; , ; – 3 November 1957) was a Soviet space dog who was one of the first animals in space and the first to orbit the Earth. A stray mongrel from the streets of Moscow, she flew aboard the Sputnik 2 spacecraft, launched into lo ...

became the first animal in orbit, with both also becoming the first fatalities of spaceflight and in space, respectively. In 1968, on

Zond 5 Zond 5 () was a spacecraft of the Soviet Zond program. In September 1968 it became the first spaceship to travel to and circle the Moon in a circumlunar trajectory, the first Moon mission to include animals, and the first to return safely to Ea ...

turtoises, insects and planets became the first animals (incl. humans) and plants to fly to and returned safely from the Moon and any extraterrestrial flight. In 2019

Chang'e 4 Chang'e 4 (; ) is a robotic spacecraft mission in the Chinese Lunar Exploration Program of the CNSA. It made a soft landing on the far side of the Moon, the first spacecraft to do so, on 3 January 2019. A communication relay satellite, , w ...

landed fruit flies on the Moon, the first extraterrestrial stay of non-human animals. Visits of organisms to extraterrestrial bodies have been a significant issue of

planetary protection Planetary protection is a guiding principle in the design of an interplanetary mission, aiming to prevent biological contamination of both the target celestial body and the Earth in the case of sample-return missions. Planetary protection refle ...

, as with the crash of tardigrades on the Moon in 2019. Plants first grown in 1966 with Kosmos 110 and in 1971 on

Salyut 1 Salyut 1 (), also known as DOS-1 (Durable Orbital Station 1), was the world's first space station. It was launched into low Earth orbit by the Soviet Union on April 19, 1971. The Salyut programme, ''Salyut'' program subsequently achieved five m ...

, with the first producing seeds August 4, 1982 on

Salyut 7 Salyut 7 (), also known as DOS-6 (Durable Orbital Station 6) was a space station in low Earth orbit from April 1982 to February 1991. It was first crewed in May 1982 with two crew via Soyuz T-5, and last visited in June 1986, by Soyuz T-15. Va ...

. The first plant to sprout on the Moon and any extraterrestrial body grew in 2019, on the

lander. Plants and growing them in space and places such as the Moon have been important subjects of space research, but also as psychological support and possibly nutrition during continuous crewed presence in space.

Direct human presence in space

Direct human presence in space was achieved with

flying a

space capsule A space capsule is a spacecraft designed to transport cargo, scientific experiments, and/or astronauts to and from space. Capsules are distinguished from other spacecraft by the ability to survive reentry and return a payload to the Earth's surfa ...

in 1961 for one orbit around Earth for the first time. While direct human presence in open space, by exiting a spacecraft in a

spacesuit A space suit (or spacesuit) is an environmental suit used for protection from the harsh Space environment, environment of outer space, mainly from its Vacuum (outer space), vacuum as a highly specialized pressure suit, but also its temperatu ...

, a so-called

extravehicular activity Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable atmosphere of Earth, Earthlike atmosphere, the astronaut is completely reliant on a space suit for environme ...

, has been achieved since the first person to do so,

Alexei Leonov Alexei Arkhipovich Leonov. (30 May 1934 – 11 October 2019) was a Soviet and Russian cosmonaut and aviator, Soviet Air Forces, Air Force major general, writer, and artist. On 18 March 1965, he became the first person to conduct a Extravehic ...

, in 1965. Though

Valentina Tereshkova Valentina Vladimirovna Tereshkova (born 6 March 1937) is a Russian engineer, member of the State Duma, and former Soviet cosmonaut. She was the first Women in space, woman in space, having flown a solo mission on Vostok 6 on 16 June 1963. S ...

was in 1963 the first woman in space, women saw no further presence in space until the 1980s and are still underrepresented, e.g. with no women ever being present on the Moon. An internationalization of direct human presence in space started with the first

space rendezvous Space is a three-dimensional continuum containing positions and directions. In classical physics, physical space is often conceived in three linear dimensions. Modern physicists usually consider it, with time, to be part of a boundless ...

of two crews of different

human spaceflight programs Human spaceflight programs have been conducted, started, or planned by multiple countries and companies. Until the 21st century, human spaceflight programs were sponsored exclusively by governments, through either the military or civilian space ...

, the

Apollo–Soyuz Apollo–Soyuz was the first crewed international Space exploration, space mission, carried out jointly by the United States and the Soviet Union in July 1975. Millions of people around the world watched on television as an American Apollo comm ...

mission in 1975 and at the end of the 1970s with the

Interkosmos Interkosmos () was a Soviet space program, designed to help the Soviet Union's allies with Human spaceflight, crewed and Uncrewed spacecraft, uncrewed space missions. The program was formed in April 1967 in Moscow. All members of the program fr ...

program.

Space station A space station (or orbital station) is a spacecraft which remains orbital spaceflight, in orbit and human spaceflight, hosts humans for extended periods of time. It therefore is an artificial satellite featuring space habitat (facility), habitat ...

s have harboured so far the only long-duration direct human presence in space. After the first station

(1971) and its tragic Soyuz 11 crew, space stations have been operated consecutively since

Skylab Skylab was the United States' first space station, launched by NASA, occupied for about 24 weeks between May 1973 and February 1974. It was operated by three trios of astronaut crews: Skylab 2, Skylab 3, and Skylab 4. Skylab was constructe ...

(1973), having allowed a progression of long-duration direct human presence in space. Long-duration direct human presence has been joined by visiting crews since 1977 (

Salyut 6 Salyut 6 () was a Soviet orbital space station, the eighth station of the Salyut programme, and alternatively known DOS-5 as it was the fifth of the Durable Orbital Station series of civilian space stations. It was launched on 29 September 19 ...

). Consecutive direct human presence in space has been achieved since the

Salyut The ''Salyut'' programme (, , meaning "salute" or "fireworks") was the first space station programme, undertaken by the Soviet Union. It involved a series of four crewed scientific research space stations and two crewed military reconnaissa ...

successor

starting with 1987. This was continued until the operational transition from the Mir to the ISS, giving rise with its first occupation to an uninterrupted direct human presence in space since 2000. While human population records in orbit developed from 1 in 1961, 2 in 1962, 4–7 in 1969, 7–11 in 1984 and 13 in 1995, to 14 in 2021, 17 in 2023 and 19 in 2024, developing into a continuous population of no less than 10 people on two space stations since 5 June 2022 (as of 2024). The ISS has hosted the most people in space at the same time, reaching 13 for the first time during the eleven day docking of

STS-127 STS-127 (Assembly of the International Space Station, ISS assembly flight 2J/A) was a NASA Space Shuttle mission to the International Space Station (ISS). It was the twenty-third flight of . The primary purpose of the STS-127 mission was to deliv ...

in 2009. Beyond Earth the Moon has been the only astronomical object which so far has seen direct human presence through the week long Apollo missions between 1968 and 1972, beginning with the first orbit by

Apollo 8 Apollo 8 (December 21–27, 1968) was the first crewed spacecraft to leave Sphere of influence (astrodynamics), Earth's gravitational sphere of influence, and the first human spaceflight to reach the Moon. The crew orbited the Moon ten times ...

in 1968 and with the first landing by

Apollo 11 Apollo 11 was a spaceflight conducted from July 16 to 24, 1969, by the United States and launched by NASA. It marked the first time that humans Moon landing, landed on the Moon. Commander Neil Armstrong and Lunar Module pilot Buzz Aldrin l ...

in 1969. The longest extraterrestrial human stay was three days by

Apollo 17 Apollo 17 (December 7–19, 1972) was the eleventh and final mission of NASA's Apollo program, the sixth and most recent time humans have set foot on the Moon. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt walked on the Moon, ...

. While most persons who have been to space are

astronauts An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a List of human spaceflight programs, human spaceflight program to serve as a commander or crew member of a spa ...

, professional members of

, particularly governmental ones, the few others, starting in the 1980s, have been trained and gone to space as

spaceflight participant Spaceflight participant () is the term used by NASA, Roscosmos, and the Federal Aviation Administration (FAA) for people who travel into space, but are not professional astronauts. While the term gained new prominence with the rise of space touris ...

s, with the first

space tourist Space tourism is human space travel for recreational purposes. There are several different types of space tourism, including orbital, suborbital and lunar space tourism. Tourists are motivated by the possibility of viewing Earth from space, ...

staying in space in 2001. By the end of the 2010s several hundred people from more than 40 countries have gone into space, most of them reaching orbit. 24 people have traveled to the Moon and 12 of them walked on the Moon. Space travelers have spent by 2007 over 29,000 person-days (or a cumulative total of over 77 years) in space including over 100 person-days of

spacewalk Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable atmosphere of Earth, Earthlike atmosphere, the astronaut is completely reliant on a space suit for environme ...

s. Usual durations for individuals to inhabit space on long-duration stays are six months, with the longest stays on record being at about a year.

Space infrastructure

A permanent human presence in space depends on an established space infrastructure which harbours, supplies and maintains human presence. Such

infrastructure Infrastructure is the set of facilities and systems that serve a country, city, or other area, and encompasses the services and facilities necessary for its economy, households and firms to function. Infrastructure is composed of public and pri ...

has originally been Earth ground-based, but with increased numbers of

satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...

s and long-duration missions beyond the

near side of the Moon The near side of the Moon is the lunar hemisphere that faces Earth, opposite to the far side. The near side of the Moon has always the same lunar surface (or "face") oriented to Earth, due to the Moon rotating on its axis at the same rate that ...

space-to-space based infrastructure is being used. First simple interplanetary infrastructures have been created by

s particularly when employing a system which combines a lander and a relaying

. Space stations are space habitats which have provided a crucial infrastructure for sustaining a continuous direct human, including non-human, presence in space. Space stations have been continuously present in orbit around Earth from

in 1973, to the Salyut stations, Mir and eventually ISS. The planned

Artemis program The Artemis program is a Exploration of the Moon, Moon exploration program led by the United States' National Aeronautics and Space Administration (NASA), formally established in 2017 via Space Policy Directive 1. The program's stated long-ter ...

includes the

Lunar Gateway The Lunar Gateway, or simply Gateway, is a planned space station which is to be assembled in orbit around the Moon. The Gateway is intended to serve as a communication hub, science laboratory, and habitation module for astronauts as part ...

a future space station around the Moon as a multimission waystation.

Spiritual and artistic

Human presence has also been expressed through spiritual and artistic installations in outer space or on the Moon.

Apollo 15 Apollo 15 (July 26August 7, 1971) was the ninth crewed mission in the Apollo program and the fourth Moon landing. It was the first List of Apollo missions#Alphabetical mission types, J mission, with a longer stay on the Moon and a greate ...

Mission Commander

David Scott David Randolph Scott (born June 6, 1932) is an American retired test pilot and NASA astronaut who was the List of Apollo astronauts#People who have walked on the Moon, seventh person to walk on the Moon. Selected as part of the NASA Astronaut ...

left for example a Bible on their

Lunar Roving Vehicle The Lunar Roving Vehicle (LRV) is a Battery electric vehicle, battery-powered four-wheeled Rover (space exploration), rover used on the Moon in the last three missions of the American Apollo program (Apollo 15, 15, Apollo 16, 16, and Apollo 17 ...

during an

on the Moon. Space has furthermore been the site of people taking part in religious festivities such as Christmas on the International Space Station.

Locations

Particular orbits

Human presence in Earth orbit and

has been the case with a range of artificial objects since the beginning of spaceflight (both possibly with debris since 1957, but for sure since 1958 with

Sputnik 1 Sputnik 1 (, , ''Satellite 1''), sometimes referred to as simply Sputnik, was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program ...

and in 1959 with

respectively), and at more interplanetary heliocentric orbits since 1961 with Venera 1. Extraterrestrial orbits other than heliocentric orbit has been achieved since 1966, starting with

around the Moon and several at the same time in orbit of the Moon that same year starting with

Lunar Orbiter 1 The 1966 Lunar Orbiter 1 robotic spacecraft mission, part of NASA's Lunar Orbiter program, was the first American spacecraft to orbit the Moon. It was designed primarily to photograph smooth areas of the lunar surface for selection and verific ...

, and since 1971 with

Mariner 9 Mariner 9 (Mariner Mars '71 / Mariner-I) was a robotic spacecraft that contributed greatly to the exploration of Mars and was part of the NASA Mariner program. Mariner 9 was launched toward Mars on May 30, 1971, from Spaceport Florida Launch Comp ...

around another planet (Mars). Humans have also used and occupied

co-orbital configuration In astronomy, a co-orbital configuration is a configuration of two or more astronomical objects (such as asteroids, moons, or planets) orbiting at the same, or very similar, distance from their primary; i.e., they are in a 1:1 mean-motion resonanc ...

s, particularly at different liberation points with

halo orbit A halo orbit is a periodic, non-planar orbit associated with one of the L1, L2 or L3 Lagrange points in the three-body problem of orbital mechanics. Although a Lagrange point is just a point in empty space, its peculiar characteristic is th ...

s, to harness the benefits of those so called

Lagrange point In celestial mechanics, the Lagrange points (; also Lagrangian points or libration points) are points of equilibrium for small-mass objects under the gravitational influence of two massive orbiting bodies. Mathematically, this involves t ...

s. Some interplanetary missions, particularly the '' Ulysses'' solar polar probe and considerably ''

'' and '' 2'', as well as others like ''

'' and '' 11'', have entered trajectories taking them out of the

ecliptic plane The ecliptic or ecliptic plane is the orbital plane of Earth around the Sun. It was a central concept in a number of ancient sciences, providing the framework for key measurements in astronomy, astrology and calendar-making. From the perspec ...

Extraterrestrial bodies

Humanity has reached different types of astronomical bodies, but the longest and most diverse presence (including non-human, e.g. sprouting plants) has been on the Moon, particularly because it is the first and only extraterrestrial body having been directly visited by humans. Space probes have been establishing and mediating human presence interplanetarily since their first visits to Venus. Mars has seen a continuous presence since 1997, after being first flown by in 1964 and landed on in 1971. A group of missions have been present on Mars since 2001, including continuous presence by a series of rovers since 2003. Beside having reached some planetary-mass objects (that is

planet A planet is a large, Hydrostatic equilibrium, rounded Astronomical object, astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets b ...

dwarf planet A dwarf planet is a small planetary-mass object that is in direct orbit around the Sun, massive enough to be hydrostatic equilibrium, gravitationally rounded, but insufficient to achieve clearing the neighbourhood, orbital dominance like the ...

s or the largest, so-called planetary-mass moons), humans have also reached, landed and in some cases even returned robotic probes from some

small Solar System bodies A small Solar System body (SSSB) is an object in the Solar System that is neither a planet, a dwarf planet, nor a natural satellite. The term was first IAU definition of planet, defined in 2006 by the International Astronomical Union (IAU) as fo ...

, like

asteroid An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

s and

comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

s, with a range of space probes. The Solar System region near the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

's corona, inside Mercury's orbit, with its high

gravitational potential In classical mechanics, the gravitational potential is a scalar potential associating with each point in space the work (energy transferred) per unit mass that would be needed to move an object to that point from a fixed reference point in the ...

difference from Earth and the subsequent high

delta-v Delta-''v'' (also known as "change in velocity"), symbolized as and pronounced , as used in spacecraft flight dynamics, is a measure of the impulse per unit of spacecraft mass that is needed to perform a maneuver such as launching from or l ...

needed to reach it, has only been considerably pierced on highly

elliptic orbit In astrodynamics or celestial mechanics, an elliptical orbit or eccentric orbit is an orbit with an eccentricity of less than 1; this includes the special case of a circular orbit, with eccentricity equal to 0. Some orbits have been referre ...

s by some solar probes like Helios 1 & 2, as well as the more contemporary

Parker Solar Probe The Parker Solar Probe (PSP; previously Solar Probe, Solar Probe Plus or Solar Probe+) is a NASA space probe launched in 2018 to make observations of the Stellar corona, Sun's outer corona. It used repeated Gravity assist, gravity assists from ...

. The latter being the closest to reach the Sun, breaking speed records with its very low solar altitudes at perihelion apsis. Future direct human presence beyond Earth's orbit is possibly going to be re-introduced if current plans for crewed

research station Research stations are facilities where scientific investigation, Data collection, collection, analysis and experimentation occurs. A research station is a facility that is built for the purpose of conducting scientific research. There are also man ...

s to be established on Mars and on the Moon are continued to be developed.

Outer Solar System

Human presence in the

has been established by the first visit to

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined a ...

in 1973 by ''Pioneer 10''. Thirty years later nine probes had traveled to the Outer Solar System, and the first such probe (JUICE, the Jupiter Icy Moons Explorer) by another space agency than NASA had just been launched on its way. Jupiter and Saturn are the only outer Solar System bodies which have been orbited by probes (Jupiter: ''Galileo (spacecraft), Galileo'' in 1995 and ''Juno (spacecraft), Juno'' in 2016; Saturn: ''Cassini–Huygens'' in 2004), with all other outer Solar System probes performing flybys. The Saturn moon Titan (moon), Titan, with its special lunar atmosphere, has so far been the only body in the outer Solar System to be landed on by the ''Cassini–Huygens'' lander ''Huygens (spacecraft), Huygens'' in 2005.

Outbound

List of artificial objects leaving the Solar System, Several probes have reached Solar

, with ''Voyager 1'' being the first to cross after 36 years of flight the Heliopause (astronomy), heliopause and enter interstellar space on August 25, 2012, at distance of 121 Astronomical unit, AU from the Sun. PIA23681-SolarSystemViewFromVoyager1-20200212

PIA23681-SolarSystemViewFromVoyager1-20200212

Living in space

ISS-43 Birthday of astronaut Samantha Cristoforetti

Living in outer space is fundamentally different to living on Earth. It is shaped by the characteristic environment of outer space, particularly its microgravity, microgravity (producing weightlessness) and its near perfect vacuum (supplying few and producing unhindered exposure to radiation and material from far away). Mundane needs such as for air, pressure, temperature and light have to be accommodated completely by life support systems. Furthermore Locomotion in space, movement, Space food, food intake and Astronautical hygiene, hygiene is confronted with challenges. Long-duration stays are particularly endangered by the prevalent Spaceflight radiation carcinogenesis, radiation exposure and the Weightlessness#Human health effects, health effects of microgravity. Human fatalities have been the case due to accidents during spaceflight, particularly at space launch, launch and reentry. With the last in-flight accident killing humans, the Columbia accident in 2003, the sum of in-flight fatalities has risen to 15 astronauts and 4 cosmonauts, in five separate incidents. Over 100 others have died in List of spaceflight-related accidents and incidents, accidents during activity directly related to spaceflight or testing. None of them remained in space, but small parts of the remains of deceased people have been taken as space burials to orbital space since 1992 and Shoemaker (lunar crater), controversially even to the Moon since 1999. STS-107 Chawla and Clark

Bioastronautics, space medicine, space technology and space architecture are fields which are occupied with alleviating the effects of space on humans and non-humans.

Culture

Research has begun into the culture and "microsocieties" that are formed in space, with space archeologists analyzing residue from space environments to learn about astronaut life. A few incidents of astronauts from different countries having difficulties in getting along have also been studied.

Impact, environmental protection and sustainability

Human space activity, and its subsequent presence, can and has been having an impact on space as well as on the capacity to access it. This impact of human space activity and presence, or its potential, has created the need to address its issues regarding planetary protection, space debris, Nuclear power in space#Regulation and hazard prevention, nuclear hazards, Radio spectrum pollution, radio pollution and Light pollution#From satellites, light pollution, to the reusable launch system, reusability of launch systems, for space not to become a sacrifice zone. Sustainability has been a goal of space law, space technology and space infrastructure, with the

seeing the need to advance long-term sustainability of outer space activities in space science and application, and the United States having it as a crucial goal of its contemporary

and space program. Human presence in space is particularly being felt in orbit around Earth. The orbital space around Earth has seen increasing and extensive human presence, beside its benefits it has also produced a threat to it by carrying with it space debris, potentially cascading into the so-called

. This has raised the need for regulation and mitigation of such to secure a sustainable access to outer space.

Study and reception

Individually or as a society humans have engaged since pre-history in developing their perception of space above the ground, or the Cosmology, cosmos at large, and developing their place in it. Social sciences have been studying such works of people from pre-history to the contemporary with the fields of archaeoastronomy to cultural astronomy. With actual human activity and presence in space the need for fields like astrosociology and space archaeology have been added.

Human presence observed from space

Earth observation has been one of the first missions of spaceflight, resulting in a dense contemporary presence of Earth observation satellites, having a wealth of uses and benefits for life on Earth. Viewing human presence from space, particularly by humans directly, has been reported by some astronauts to cause a cognitive shift in perception, especially while viewing the Earth from outer space, this effect has been called the overview effect.

Observation of space from space

Parallel to the above ''overview effect'' the term "ultraview effect" has been introduced for a subjective response of intense awe some astronauts have experienced viewing large "starfields" while in space. Space observatory, Space observatories like the Hubble Space Telescope have been present in Earth's orbit, benefiting from advantages from being outside Earth's atmosphere and away from its radio noise, resulting in less distorted observation results.

Direct and mediated human presence

Related to the long discussion of what human presence constitutes and how it should be lived, the discussion about direct (e.g. crewed) and mediated (e.g. uncrewed) human presence, has been decisive for how space policy makers have chosen human presence and its purposes. The relevance of this issue for space policy has risen with the advancement and resulting possibilities of telerobotics, to the point where most of the human presence in space has been reallized robotically, leaving direct human presence behind.

Localization in space

The location of human presence has been studied throughout history by astronomy and was significant in order to relate to the heavens, that is to outer space and its bodies. The historic argument between geocentrism and heliocentrism is one example about the location of human presence.

Scenarios of and relations to space beyond human presence

Realizations of the Location of Earth, scales of space, have been taken as subject to discuss human and life's existence or relations to spacetime, space and time beyond them, with some understanding humanity's or life's presence as a Rare Earth hypothesis, singularity or one to be in Uncontacted peoples, isolation, pondering on the Fermi paradox. A diverse range of arguments of how to relate to space beyond human presence have been raised, with some seeing space beyond humans as reason to venture out into space and exploring it, some aiming for first contact (anthropology), contact with extraterrestrial life, to arguments for planetary protection, protection of humanity or life from its possibilities. Considerations about the ecological integrity and independence of celestial bodies, counter exploitive understandings of space as dead, particularly in the sense of

, have raised issues such as rights of nature.

Purposes and uses

Space and human presence in it has been the subject of different agendas. Human presence in space at its beginnings, was fueled by the Cold War and its outgrowing the Space Race. During this time technological, nationalist, ideological and Militarization of space, military competition were dominant driving factors of space policy and the resulting activity and, particularly direct human, presence in space. With the waning of the Space Race, concluded by Apollo–Soyuz, cooperation in human spaceflight, focus shifted in the 1970s further to space exploration and telerobotics, having a range of achievements and technological advances. Space exploration meant by then also an engagement by governments in the search for extraterrestrial life. Since human activity and presence in space has been producing Benefits of space exploration, spin-off benefits, other than for the above purposes, such as Earth observation and communication satellites for civilian use, international cooperation to advance such benefits of human presence in space grew with time. Particularly for the purpose of continuing benefits of space infrastructure and

the United Nations has been pushing for safeguarding Space sustainability, human activity in outer space in a sustainable way. With the contemporary so-called NewSpace, the aim of commercialization of space has grown along with a narrative of space habitation for the Space and survival, survival of some humans away from and without Earth, which in turn has been critically analyzed and highlighted Space colonization#Colonialism, colonialist purposes for human activity and presence in space. This has given rise for a deeper engagement in the fields of space environment and space ethics.

Overview of different purposes and uses

* Space exploration#Rationales ** Benefits of space exploration *** NASA spinoff technologies ** Space research *** Earth observation **** Astronomy ***** Space observatory **** Search for extraterrestrial life (see also First contact (anthropology), first contact) ** Communications satellite, Communication ** Spaceflight/Space transportation ** Commercial use of space *** Space tourism *** Space mining (see also Planetary surface#Surface chauvinism and surfacism, Surface chauvinism and surfacism) *** Space manufacturing *** Environmental dumping ** Planetary protection *** Planetary defense *** Isolationism * For presence, in itself (see Human outpost space basing) ** Space imperialism *** Nationalism, National or private potency and Bellum omnium contra omnes, competition (see Space Race) *** Militarization of space ** Extraterrestrial settlement *** Emigration from Earth **** Social integration, Integration or naturalization (see also Naturalization (biology), biological naturalization such as Pantropy) **** Human migration#Push and Pull, Demographic push (e.g. due to overconsumption) **** Forced displacement **** Space and survival **** Escapism ** Space development as a purpose of progress (see also New Frontier) *** Expansionism **** Space colonization **** Civilizing mission ***** Terraforming (see also Ethics of terraforming) ***** Directed panspermia