Space settlement

Space colonization has been in a broad sense referred to as space settlement, space humanization or space habitation. Space colonization in a narrow sense refers to space settlements, as envisioned by Gerard K. O'Neill. It is characterized by elements such as: settlement and exploitation, as well as territorial claim.

The concept in its broad sense has been applied to any permanent human presence, even robotic, particularly along with the term "settlement", being imprecisely applied to any human space habitat, from research stations to self-sustaining communities in space.

The words colony and colonization are terms rooted in colonial history on Earth, making them human geographic as well as particularly political terms. This broad use for any permanent human activity and development in space has been criticized, particularly as colonialist and undifferentiated (see below Objections).

In this sense, a colony is a settlement that claims territory and exploits it for the settlers or their metropole. Therefore, a human outpost, while possibly a space habitat or even a space settlement, does not automatically constitute a space colony.

Some have argued the presence of certain mechanisms or institutions are symptoms of having achieved a "critical mass"; for instance, sci-fi author Neal Stephenson argued a small Martian colony would feel more like living on a U.S. Navy nuclear submarine than being part of a vibrant community while economists Karl T. Muth and Jodi N. Beggs argued that, to meet American cultural and judicial norms, a Martian colony would need a large enough population to offer a defendant a jury of twelve strangers.

Therefore, any basing can be part of colonization, while colonization can be understood as a process that is open to more claims, beyond basing. The International Space Station, the longest-occupied extraterrestrial habitat thus far, does not claim territory and thus is not usually considered a colony.

Moriba Jah has criticized existing approaches to orbital space as colonialist, such as for satellites, on the grounds that it involves claiming ownership instead of collaborative stewardship.

Some advocates of peaceful human settlement of space have argued against use of the word "colony" and related terms, so as to avoid confusing their goals with colonialism on Earth.

In the first half of the 17th century John Wilkins suggested in A Discourse Concerning a New Planet that future adventurers like Francis Drake and Christopher Columbus might reach the Moon and allow people to live there. The first known work on space colonization was the 1869 novella The Brick Moon by Edward Everett Hale, about an inhabited artificial satellite. In 1897, Kurd Lasswitz also wrote about space colonies in his book Auf zwei Planeten (Two Planets). The Russian rocket science pioneer Konstantin Tsiolkovsky foresaw elements of the space community in his book Beyond Planet Earth written about 1900. Tsiolkovsky imagined his space travelers building greenhouses and raising crops in space. Tsiolkovsky believed that going into space would help perfect human beings, leading to immortality and peace. One of the first to speak about space colonization was Cecil Rhodes who in 1902 spoke about "these stars that you see overhead at night, these vast worlds which we can never reach", adding "I would annex the planets if I could; I often think of that. It makes me sad to see them so clear and yet so far". In the 1920s John Desmond Bernal, Hermann Oberth, Guido von Pirquet and Herman Noordung further developed the idea. Wernher von Braun contributed his ideas in a 1952 Colliers magazine article. In the 1950s and 1960s, Dandridge M. Cole published his ideas.

When orbital spaceflight was achieved in the 1950s colonialism was still a strong international project, e.g. easing the United States to advance its space program and space in general as part of a "New Frontier". As the Space Age was developing, decolonization gained again in force, producing many newly independent countries. These newly independent countries confronted spacefaring countries, demanding an anti-colonial stance and regulation of space activity when space law was raised and negotiated internationally. Fears of confrontations because of land grabs and an arms race in space between the few countries with spaceflight capabilities grew and were ultimately shared by the spacefaring countries themselves. …

A primary argument calling for space colonization is the long-term survival of human civilization and terrestrial life. By developing alternative locations off Earth, the planet's species, including humans, could live on in the event of natural or human-made disasters on Earth.

On two occasions, theoretical physicist and cosmologist Stephen Hawking argued for space colonization as a means of saving humanity. In 2001, Hawking predicted that the human race would become extinct within the next thousand years unless colonies could be established in space. In 2010, he stated that humanity faces two options: either we colonize space within the next two hundred years, or we will face the long-term prospect of extinction.

In 2005, then NASA Administrator Michael Griffin identified space colonization as the ultimate goal of current spaceflight programs, saying:

... the goal isn't just scientific exploration ... it's also about extending the range of human habitat out from Earth into the solar system as we go forward in time ... In the long run, a single-planet species will not survive ... If we humans want to survive for hundreds of thousands of millions of years, we must ultimately populate other planets. Now, today the technology is such that this is barely conceivable. We're in the infancy of it. ... I'm talking about that one day, I don't know when that day is, but there will be more human beings who live off the Earth than on it. We may well have people living on the Moon. We may have people living on the moons of Jupiter and other planets. We may have people making habitats on asteroids ... I know that humans will colonize the solar system and one day go beyond.

Louis J. Halle Jr., formerly of the United States Department of State, wrote in Foreign Affairs (Summer 1980) that the colonization of space will protect humanity in the event of global nuclear warfare. The physicist Paul Davies also supports the view that if a planetary catastrophe threatens the survival of the human species on Earth, a self-sufficient colony could "reverse-colonize" Earth and restore human civilization. The author and journalist William E. Burrows and the biochemist Robert Shapiro proposed a private project, the Alliance to Rescue Civilization, with the goal of establishing an off-Earth "backup" of human civilization.

Based on his Copernican principle, J. …

Space colonization has been seen as a relief to the problem of human overpopulation as early as 1758, and listed as one of Stephen Hawking's reasons for pursuing space exploration. Critics note, however, that a slowdown in population growth rates since the 1980s has alleviated the risk of overpopulation.

Critics also argue that the costs of commercial activity in space are too high to be profitable against Earth-based industries, and hence that it is unlikely to see significant exploitation of space resources in the foreseeable future.

Other objections include concerns that the forthcoming colonization and commodification of the cosmos is likely to enhance the interests of the already powerful, including major economic and military institutions e.g. the large financial institutions, the major aerospace companies and the military–industrial complex, to lead to new wars, and to exacerbate pre-existing exploitation of workers and resources, economic inequality, poverty, social division and marginalization, environmental degradation, and other detrimental processes or institutions.

Additional concerns include creating a culture in which humans are no longer seen as human, but rather as material assets. …

Colonization beyond the Earth involves overcoming a number of difficult challenges.

The outer planets are much farther from Earth than the inner planets, and would therefore be harder and more time-consuming to reach. In addition, return voyages may well be prohibitive considering the time and distance. Even communication with Earth would be slow, with delays of 4–24 minutes for a message to Mars, and 35–52 minutes to Jupiter and its moons.

Extreme cold – due to the distance to the sun, temperatures are near absolute zero in many parts of the outer Solar System.

Power – Solar power is many times less concentrated in the outer Solar System than in the inner Solar System. It is unclear as to whether it would be usable there, using some form of concentration mirrors, or whether nuclear power would be necessary. Use of geothermal systems to generate power may be practical on some of the planets and moons of the solar system.

The health of the humans who may participate in a colonization venture would be subject to increased physical, mental and emotional risks.