Aliens
![Intelligent Aliens: Artist's Illustration](https://cdn.mos.cms.futurecdn.net/idzyPDTtTT7KgXJoTpmuoG-320-80.jpg)
Aliens can refer to everything from little green men in the sci-fi realm to microscopic life forms beyond Earth. For all these possibilities, Live Science has you covered. We break down the latest discoveries that hint at life on other planets and the state of scientific searches for such extraterrestrial life. Sometimes, we may dissect a "little green man" sighting as well.
Latest about Extraterrestrial Life
![An illustration of a green and blue planet in space with light shining on it.](https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/nb5Jep3eFRYgCkk6wboxRd-1200-80.jpg 1200w)
What's the best evidence we've found for alien life?
By Patrick Pester published
Don't expect an alien invasion anytime soon.
![Life requires repetition of chemical reactions. Describing the kinds of reactions and conditions required for self-sustaining repetition — called autocatalysis — could focus the search for life on other planets.](https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/WntpM3BTWwGmTt8nE9zpsj-1200-80.jpg 1200w)
Alien life may evolve from radically different elements than human life did
By Charles Q. Choi published
Radioactive metals and even certain gases may be capable of the kinds of reactions needed to spur life, new research suggests.
![NASA's Curiosity rover took this selfie while inside Mars' Gale crater on June 15, 2018, which was the 2,082nd Martian day, or sol, of the rover's mission.](https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/ubY9QH5fSdZMMco9rYuiP4-1200-80.jpg 1200w)
Scientists created AI that could detect alien life — and they're not entirely sure how it works
By Ben Turner published
The new machine-learning algorithm can distinguish between biological and nonbiological samples with 90% accuracy. Exactly how is a mystery.
![A still from a U.S. Navy video reportedly showing an unidentified anomalous phenomena encountered in military airspace off America's east coast in 2015.](https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/HT7Ceu5nYWoE3DbUycrGr7-1200-80.jpg 1200w)
No aliens in NASA's debut UFO report — but big questions remain
By Brett Tingley published
In the agency's first public report on unidentified anomalous phenomena (UAP), NASA experts admit "we don't know what these UAP are."
![An artist's illustration of the OSIRIS-REx spacecraft poised to land on the asteroid Bennu.](https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/cur28rN9WEuiWz9YSG6foD-1200-80.jpg 1200w)
NASA's OSIRIS-REx mission almost bit the dust — then Queen guitarist Brian May stepped in
By Ben Turner published
The OSIRIS-REx spacecraft will soon return to Earth. What's on board could reveal the extraterrestrial origins of life on Earth.
![Is the Pentagon secretly witholding evidence that UFOs have non-human origins?](https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/Kzp6s7j4bmLwBn7Sn5giNJ-1200-80.jpg 1200w)
US government is hiding evidence of 'non-human intelligence', UFO whistleblower tells Congress
By Brett Tingley published
During a congressional hearing on Wednesday (July 26), military witnesses claimed that evidence of non-human technology is being hidden from the public.
![An illustration of a flying saucer looking pitch-black against the starry night sky](https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/tVz4Ndv87iiEHrxqdGSkNb-1200-80.jpg 1200w)
First contact with aliens could easily end in genocide, scholars warn
By David Delgado Shorter published
SETI has been searching for evidence of alien life – but could doing so end in disaster?
![A microscopic metal ball glitters with various elements](https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-320-80.jpg 320w, https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-450-80.jpg 450w, https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-500-80.jpg 500w, https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-650-80.jpg 650w, https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-840-80.jpg 840w, https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-970-80.jpg 970w, https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-1024-80.jpg 1024w, https://cdn.mos.cms.futurecdn.net/Jyq5QULaJKuV38dqAp9e29-1200-80.jpg 1200w)
'Anomalous' metal spheres unlikely to be alien technology, despite Harvard scientist's claim
By Joanna Thompson published
A prominent extraterrestrial-hunting scientist thinks that more than 50 tiny, metal spheres pulled from the Pacific Ocean might be the work of intelligent aliens. Others are skeptical.
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