Extraterrestrial intelligence in the context of Copernican Revolution

Extraterrestrial life, or alien life (colloquially, aliens), is life that originates from another world rather than on Earth. No extraterrestrial life has yet been scientifically or conclusively detected. Such life might range from simple forms such as prokaryotes to intelligent beings, possibly bringing forth civilizations that might be far more, or far less, advanced than humans. The Drake equation speculates about the existence of sapient life elsewhere in the universe. The science of extraterrestrial life is known as astrobiology.

Personism is an ethical philosophy of personhood as typified by the thought of the utilitarian philosopher Peter Singer. It amounts to a branch of secular humanism with an emphasis on certain rights-criteria. Personists believe that rights are conferred to the extent that a creature is a person. Michael Tooley provides the relevant definition of a person, saying it is a creature that is "capable of desiring to continue as a subject of experience and other mental states".

A worldview like secular humanism is personism when the empathy and values are extended to the extent that the creature is a person, so for example apes get very similar rights while insects get vastly fewer rights. Consequently, a member of the human species may not necessarily fit the definition of "person" and thereby not receive all the rights bestowed to a person. Hence, such philosophers have engaged in arguing that certain disabled individuals (such as those with a mental capacity that is similar to or is perceived as being similar to an infant) are not persons. This philosophy is also supposedly open to the idea that such non-human persons as machines, animals, and extraterrestrial intelligences may be entitled to certain rights currently granted only to humans. The basic criteria for the entitlement of rights, are the intellect (thinking ability, problem solving in real life circumstances, and not mere calculation), and sometimes empathy, although not necessarily, as not all humans are empathetic; however, indifference in the pain of others and crime are certainly criteria for the deprivation of rights. Genuine empathy is not required to achieve acceptable behavior, but a digital limbic system and a dopaminergic pathways alternative, would deliver a more acceptable result for future MPs judging on rights expansion. Personism may have views in common with transhumanism.

In astronomy and astrobiology, the habitable zone (HZ), the circumstellar habitable zone (CHZ), the Goldilocks zone, is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure. The bounds of the HZ are based on Earth's position in the Solar System and the amount of radiant energy it receives from the Sun. Due to the importance of liquid water to Earth's biosphere, the nature of the HZ and the objects within it may be instrumental in determining the scope and distribution of planets capable of supporting Earth-like extraterrestrial life and intelligence. As such, it is considered by many to be a major factor of planetary habitability, and the most likely place to find extraterrestrial liquid water and biosignatures elsewhere in the universe.

The habitable zone is also called the Goldilocks zone, a metaphor, allusion and antonomasia of the children's fairy tale of "Goldilocks and the Three Bears", in which a little girl chooses from sets of three items, rejecting the ones that are too extreme (large or small, hot or cold, etc.), and settling on the one in the middle, which is "just right".

Ancient astronauts (or ancient aliens) refers to a pseudoscientific set of beliefs, also called paleocontact, that hold that intelligent extraterrestrial beings (alien astronauts) visited Earth and made contact with humans in antiquity and prehistoric times. Proponents of the theory suggest that this contact influenced the development of modern cultures, technologies, religions, and human biology. A common position is that deities from most (if not all) religions are extraterrestrial in origin, and that advanced technologies brought to Earth by ancient astronauts were interpreted as evidence of divine status by early humans.

The idea that ancient astronauts existed and visited Earth is not taken seriously by academics and archaeologists, who identify such claims as pseudoarchaeological or unscientific. It has received no credible attention in peer-reviewed studies. When proponents of the idea present evidence in favor of their beliefs, it is often distorted or fabricated. Some authors and scholars also argue that ancient astronaut theories have racist undertones or implications, diminishing the accomplishments and capabilities of indigenous cultures.

The politics of outer space includes space treaties, law in space, international cooperation and conflict in space exploration, international economics, and the hypothetical political impact of any contact with extraterrestrial intelligence.

Astropolitics has its foundations in geopolitics and is a theory that is used for space in its broadest sense.

The extraterrestrial UFO hypothesis or extraterrestrial hypothesis (ETH), synonymous with interplanetary aircraft and alien UFO technologies, proposes that some unidentified flying objects (UFOs) are best explained as being physical spacecraft occupied by intelligent extraterrestrial organisms (non-human aliens) from other planets, or probes designed by extraterrestrials.

The scientific community has shown very little support for the ETH, and has largely accepted the explanation that reports of UFOs are the result of people misinterpreting common objects or phenomena, or are the work of hoaxers.

Mars, the fourth planet from the Sun, has appeared as a setting in works of fiction since at least the mid-1600s. Trends in the planet's portrayal have largely been influenced by advances in planetary science. It became the most popular celestial object in fiction in the late 1800s, when it became clear that there was no life on the Moon. The predominant genre depicting Mars at the time was utopian fiction. Around the same time, the mistaken belief that there are canals on Mars emerged and made its way into fiction, popularized by Percival Lowell's speculations of an ancient civilization having constructed them. The War of the Worlds, H. G. Wells's novel about an alien invasion of Earth by sinister Martians, was published in 1897 and went on to have a major influence on the science fiction genre.

Life on Mars appeared frequently in fiction throughout the first half of the 1900s. Apart from enlightened as in the utopian works from the turn of the century, or evil as in the works inspired by Wells, intelligent and human-like Martians began to be depicted as decadent, a portrayal that was popularized by Edgar Rice Burroughs in the Barsoom series and adopted by Leigh Brackett among others. More exotic lifeforms appeared in stories like Stanley G. Weinbaum's "A Martian Odyssey".