Extraterrestrial Life

Extraterrestrial life or alien life is life which may occur outside Earth and which did not originate on Earth. No extraterrestrial life has yet been conclusively detected. Such life might range from simple forms such as prokaryotes to intelligent beings, possibly bringing forth civilizations that might be far more advanced than humanity. The Drake equation speculates about the existence of sapient life elsewhere in the universe. The science of extraterrestrial life is known as astrobiology.

Speculation about the possibility of inhabited worlds beyond Earth dates back to antiquity. Early Christian writers discussed the idea of a "plurality of worlds" as proposed by earlier thinkers such as Democritus; Augustine references Epicurus's idea of innumerable worlds "throughout the boundless immensity of space" (originally expressed in his Letter to Herodotus) in The City of God. In his first-century poem De rerum natura (Book 2:1048–1076), the Epicurean philosopher Lucretius predicted that humanity would find innumerable exoplanets with life-forms similar to, and different from, the ones on Earth, and even other races of man.

Pre-modern writers typically assumed extraterrestrial "worlds" are inhabited by living beings. William Vorilong, in the 15th century, acknowledged the possibility that Jesus could have visited extraterrestrial worlds to redeem their inhabitants. Nicholas of Cusa wrote in 1440 that Earth is "a brilliant star" like other celestial objects visible in space, which would appear similar to the Sun from an exterior perspective due to a layer of "fiery brightness" in the outer layer of the atmosphere. He theorised all extraterrestrial bodies could be inhabited by men, plants, and animals, including the Sun. Descartes wrote that there was no means to prove that the stars were not inhabited by "intelligent creatures", but their existence was a matter of speculation. The writings of these individuals demonstrate interest in extraterrestrial life has existed throughout history, although only recently have humans have had any means of investigating it.

Since the mid-20th century, active research has taken place to look for signs of extraterrestrial life, encompassing searches for current and historic extraterrestrial life, and a narrower search for extraterrestrial intelligent life. Depending on the category of search, methods range from the analysis of telescope and specimen data to radios used to detect and transmit communications.

The concept of extraterrestrial life, and particularly extraterrestrial intelligence, has had a major cultural impact, especially extraterrestrials in fiction. Science fiction has communicated scientific ideas, imagined a wide range of possibilities, and influenced public interest in and perspectives on extraterrestrial life. One shared space is the debate over the wisdom of attempting communication with extraterrestrial intelligence. Some encourage aggressive methods to try to contact intelligent extraterrestrial life. Others – citing the tendency of technologically advanced human societies to enslave or destroy less advanced societies – argue it may be dangerous to actively draw attention to Earth.

Source: Extraterrestrial life (wikipedia.org)

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Many astronomers are no longer asking whether there is life elsewhere in the Universe. The question on their minds is instead: when will we find it?

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Tantalising sign of possible life on faraway world

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The UFO reports piquing Nasa's interest

It was just a normal day's flying for Alex Dietrich – until it wasn't. Streaking through the sky over the tranquil expanse of the Pacific Ocean near San Diego, the US Navy lieutenant commander was taking her F/A-18F Super Hornet fighter jet on a training mission with a colleague in another plane.

UFOs and aliens bring a divided US Congress together

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Should extraterrestrial life be granted 'sentient' rights?

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UFOs: Five revelations from Nasa's public meeting

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European Space Agency: Jupiter moons mission set for second launch bid

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Why Aliens Might Already Be On Their Way To Us

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Life on Mars? Australian rocks may hold clues for Nasa rover

Rocks in the Australian Outback dating back 3.5 billion years may help scientists work out whether there has ever been life on Mars. Researchers studying the Australian rocks say only ancient microbes could have shaped them the way they are.

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To play this video you need to enable JavaScript in your browser.The US space agency's Perseverance rover is close to completing its first set of objectives on Mars.

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To play this video you need to enable JavaScript in your browser.In a flat on the island of Cumbrae, off the west coast of Scotland, a geologist has turned his kitchen into a hub in the search for signs of life on Mars.

Perseverance: Nasa rover begins key drive to find life on Mars

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Arthur C. Clarke on Why Aliens Would Be Superior To Humans | The Dick Cavett Show

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Life could exist on planet orbiting 'white dwarf' star

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How to Find ALIEN Dyson Spheres

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Mars scientists now know where to look for life

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Clouds of Venus 'simply too dry' to support life

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UFO report: US finds no explanation for sightings

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Pentagon won't rule out aliens in long-awaited UFO report

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Nasa Mars rover: How Perseverance will hunt for signs of past life

Nasa's Perseverance rover, due to launch to Mars this summer, will search an ancient crater lake for signs of past life. But if biology ever emerged on the Red Planet, how will scientists recognise it? Here, deputy project scientist Ken Williford explains what they're looking for.

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Europa Clipper: Nasa's ocean world mission gets launch date

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Extraterrestrial life

Extraterrestrial life,[n 1] sometimes colloquially referred to as alien life, is life that may occur outside Earth and which did not originate on Earth. No extraterrestrial life has yet been conclusively detected, although efforts are underway.

Alien life 'may exist among us'

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Alien thinking

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Alien oceans could be detected by telescopes

The next generation of telescopes could reveal the presence of oceans on planets outside our Solar System. Detecting water on Earth-like planets offers the tantalising prospect they could sustain life.

Alien hunters 'should look for artificial intelligence'

Seti, the Search for Extraterrestrial Intelligence, has until now sought radio signals from worlds like Earth. But Seti astronomer Seth Shostak argues that the time between aliens developing radio technology and artificial intelligence (AI) would be short.

47 year old television signals bouncing back to Earth

While searching deep space for extra-terrestrial signals, scientists at the Arecibo Observatory in Puerto Rico have stumbled across signals broadcast from Earth nearly half a century ago. Radio astronomer Dr.

'No signal' from targeted ET hunt

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'No evidence' for extraterrestrials, says White House

The US government has formally denied that it has any knowledge of contact with extraterrestrial life. The announcement came as a response to submissions to the We The People website, which promises to address any petition that gains 5,000 signatories.

Hubble's role in search for aliens

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UFOs: Few answers at rare US Congressional hearing

The first public congressional hearing into UFO sightings in the US in over 50 years ended with few answers about the unexplained phenomenon. Two top military officials tasked with probing the sightings said that most can ultimately be identified.

Pentagon to study UFO sightings in restricted US airspace

US defence officials have announced the launch of a task force to investigate reports of unidentified flying objects in restricted airspace. The group will assess objects of interest and "mitigate any associated threats", the Pentagon said on Tuesday.

Pentagon releases UFO videos for the record

The US Department of Defense has released three declassified videos of "unexplained aerial phenomena". The Pentagon said it wanted to "clear up any misconceptions by the public on whether or not the footage that has been circulating was real".

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