Please forward this error screen to host. Please forward this error screen to sharedip-19218625533. Jump to navigation Jump to search For other uses, see Astrobiology.
Some major international efforts to search for extraterrestrial life. Earth and that probably did not originate from Earth. Since the mid-20th century, there has been an ongoing search for signs of extraterrestrial life.
This encompasses a search for current and historic extraterrestrial life, and a narrower search for extraterrestrial intelligent life. The concept of extraterrestrial life, and particularly extraterrestrial intelligence, has had a major cultural impact, chiefly in works of science fiction. Over the years, science fiction communicated scientific ideas, imagined a wide range of possibilities, and influenced public interest in and perspectives of extraterrestrial life.
Alien life, such as microorganisms, has been hypothesized to exist in the Solar System and throughout the universe. Since the 1950s, scientists have proposed that “habitable zones” around stars are the most likely places to find life. Numerous discoveries in such zones since 2007 have generated numerical estimates of Earth-like planets —in terms of composition—of many billions. A study published in 2017 suggests that due to how complexity evolved in species on Earth, the level of predictability for alien evolution elsewhere would make them look similar to life on our planet. One of the study authors, Sam Levin, notes “Like humans, we predict that they are made-up of a hierarchy of entities, which all cooperate to produce an alien.