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261:
that an extraterrestrial civilization could be advanced enough to dispense with biology, living instead inside of advanced computers. The medium through which humanity is contacted, be it electromagnetic radiation, direct physical interaction, extraterrestrial artefact, or otherwise, may also influence the results of contact. Incorporating these factors, various systems have been created to assess the implications of extraterrestrial contact.
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222:'s position, in line with that of most relevant experts, is that "chances of contact with an extraterrestrial intelligence are extremely small, given the distances involved." This line of thinking has led some to conclude that first contact might be made with extraterrestrial artificial intelligence, rather than with biological beings.
269:. Such meetings have generally led to the destruction of the civilization receiving contact (as opposed to the "contactor", which initiates contact), and therefore destruction of human civilization is a possible outcome. However, the absence of any such contact to date means such conjecture is largely speculative.
55:
demonstrated that the Earth was a planet revolving around the Sun, and other planets were, conversely, other worlds. The question of whether other inhabited planets or moons exist was a natural consequence of this new understanding. It has become one of the most speculative questions in science and
260:
The potential changes from extraterrestrial contact could vary greatly in magnitude and type, based on the extraterrestrial civilization's level of technological advancement, degree of benevolence or malevolence, and level of mutual comprehension between itself and humanity. Some theories suggest
59:
An alternative name for it is "Extraterrestrial
Technological Instantiations" (ETI). The term was coined to avoid the use of terms such as "civilizations" "species" and "intelligence", as those may prove to be ambiguous and open to interpretation, or simply inapplicable in its local context.
935:"A Chinese Telescope Did Not Find an Alien Signal. The Search Continues. China's astronomers have been initiated into the search for extraterrestrial intelligence with the kind of false alarm that others in the field have experienced for decades"
203:(CETI) is a branch of the search for extraterrestrial intelligence that focuses on composing and deciphering messages that could theoretically be understood by another technological civilization. The best-known CETI experiment was the 1974
264:
The implications of extraterrestrial contact, particularly with a technologically superior civilization, have often been likened to the meeting of two vastly different human cultures on Earth, a historical precedent being the
193:(Active Search for Extra-Terrestrial Intelligence) is the attempt to send messages to intelligent extraterrestrial life. Active SETI messages are usually sent in the form of radio signals. Physical messages like that of the
237:
reported the possibility of having detected artificial (presumably alien) signals, but cautions that further studies are required to determine if some kind of natural radio interference may be the source. On 18 June 2022
229:
remains the best candidate for an extraterrestrial radio signal ever detected, though the fact that no similar signal has ever been observed again makes attribution of the signal to any cause difficult if not impossible.
100:, is a concept sometimes mistakenly used to refer to the concept of intelligence and sapience, since it does not exclude forms of life that are non-sapient (or more broadly non-intelligent or non-conscious).
51:. No such life has ever been verifiably observed to exist. The question of whether other inhabited worlds might exist has been debated since ancient times. The modern form of the concept emerged when the
849:
686:", The search for extraterrestrial life: Recent developments; Proceedings of the Symposium, Boston, MA, June 18–21, 1984 (A86-38126 17-88). Dordrecht, D. Reidel Publishing Co., 1985, p. 497–504.
300:
400:
311:
The theories and reception of the probability of intelligent life has been a recurring cultural element, particularly of popular culture since the prospect and achievement of
131:
highlights the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilization and humanity's lack of contact with, or
107:
frames a more particular case of extraterrestrial intelligence. It is the possible long-term result of intelligent and specifically sapient extraterrestrial life.
857:
255:
741:
246:-related projects, reportedly noted that “These signals are from radio interference; they are due to radio pollution from earthlings, not from E.T.”
200:
234:
1016:
624:
127:
have proposed that the sheer scale of the universe makes it improbable for intelligent life not to have emerged elsewhere. However,
184:
596:
449:
Plurality of Worlds: The
Extraterrestrial life Debate from Democritus to Kant, by Steven Dick, Cambridge University Press 1984
668:
No life beyond Earth has ever been found; there is no evidence that alien life has ever visited our planet. It's all a story.
434:
796:
189:
There has been a search for signals from extraterrestrial intelligence for several decades, with no significant results.
771:
579:
683:
17:
903:
374:
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Harrison, A. A. (2011). "Fear, pandemonium, equanimity and delight: Human responses to extra-terrestrial life".
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concept that humans are not privileged observers of the universe. Many prominent scientists, including
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1092:
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So far, there is no observation of extraterrestrial life, including intelligent extraterrestrial life.
934:
168:
framework used to estimate the number of active, communicative extraterrestrial civilizations in the
1020:
966:
Philosophical
Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
571:
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384:
337:
332:
287:
52:
48:
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120:
116:
458:
The
Extraterrestrial Life Debate: 1750-1900, by Michael J. Crowe, Dover Publications, 2011
8:
1196:
629:
215:. There are multiple independent organizations and individuals engaged in CETI research.
977:
86:
or wiser, first coined by Karen
Anderson and published in the 1966 works by her husband
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997:
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266:
165:
128:
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1017:"The Impact of ET Contact: Europe's Scientists Discuss The Future of Humans in Space"
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1101:
930:
908:
850:""Alien Artificial Intelligence is Out There" --And It's Billions of Years Old"
394:
296:
291:
in this context). As an explanation for UFOs, ETI is sometimes contrasted with
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are vehicles containing or sent by extraterrestrial beings (usually called
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45:
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208:
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1096:
700:[It was like a 180 degree turn from this embarrassing secret].
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476:
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212:
150:
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684:
On the
Inevitability and the Possible Structures of Supercivilizations
878:
828:
702:
496:
169:
93:
301:
hearing to examine how the executive branch handles reports of UFOs
1119:
405:
389:
132:
69:
1131:
493:"Are we alone? Intelligent aliens may be rare, new study suggests"
801:
698:"Es war wie eine 180-Grad-Wende von diesem peinlichen Geheimnis!"
401:
Extraterrestrial: The First Sign of
Intelligent Life Beyond Earth
380:
Messaging to Extra-Terrestrial
Intelligence (METI or Active SETI)
172:
154:
83:
519:"Consciousness, Sapience and Sentience—A Metacybernetic View"
243:
178:
56:
is a central theme of science fiction and popular culture.
1155:
904:"Has China's FAST telescope detected alien intelligence?"
824:"Electronic E.T.: Intelligent Aliens Are Likely Machines"
282:
68:
Intelligence is, along with the more precise concept of
720:"The search for ET is a detective story without a body"
319:
has even declared in 2003 the 14th of
February as the
72:, used to describe extraterrestrial life with similar
1108:
256:
Potential cultural impact of extraterrestrial contact
250:
Potential cultural impact of extraterrestrial contact
1044:
772:"No Alien Visits or UFO Coverups, White House Says"
559:
469:
233:On 14 June 2022 astronomers working with China's
1216:
201:Communication with extraterrestrial intelligence
1062:"Extraterrestrial Culture Day landed on Feb.14"
797:"What if the aliens we are looking for are AI?"
197:may also be considered an active SETI message.
1008:
27:Hypothetical intelligent extraterrestrial life
959:
957:
597:"Stephen Hawking takes a hard line on aliens"
1014:
923:
490:
895:
622:
76:as humans. Another interchangeable term is
954:
733:
715:
713:
623:Krauthammer, Charles (December 29, 2011).
534:
963:
769:
763:
588:
185:Search for extraterrestrial intelligence
179:Search for extraterrestrial intelligence
929:
742:"Searching for ET, But No Evidence Yet"
710:
650:
594:
557:
429:. United States: Pearson. p. 3-4.
424:
145:is a speculative method of measuring a
14:
1217:
1041:
794:
739:
516:
467:
689:
1054:
901:
821:
695:
153:advancement, based on the amount of
770:Atkinson, Nancy (5 November 2011).
510:
293:EDI (extradimensional intelligence)
157:a civilization is able to utilize.
24:
299:. In 2023, House lawmakers held a
25:
1246:
1086:
651:Kaufman, Marc (12 October 2022).
616:
1202:
1190:
1178:
1166:
1154:
1142:
1130:
1118:
1093:An astrophysicist's view of UFOs
740:Larson, Phil (5 November 2011).
696:Zaun, Harald (1 November 2011).
491:Keith Cooper (August 20, 2024).
1035:
871:
842:
822:Wall, Mike (14 November 2016).
815:
788:
673:
644:
625:"Are we alone in the universe?"
404:, 2021 popular science book by
375:Life origination beyond planets
360:First contact (science fiction)
63:
1019:. Daily Galaxy. Archived from
1015:Kazan, Casey (1 August 2008).
595:Hickman, Leo (25 April 2010).
551:
517:Yolles, Maurice (2022-12-13).
484:
468:Spinks, Peter (May 21, 2013).
461:
452:
443:
418:
242:, chief scientist for several
110:
13:
1:
902:Byrd, Deborah (4 June 2022).
411:
306:
105:extraterrestrial civilization
38:Extraterrestrial intelligence
879:"Was the Wow! Signal Alien?"
856:. 2019-01-01. Archived from
355:Extraterrestrials in fiction
321:Extraterrestrial Culture Day
32:Extraterrestrials in fiction
7:
326:
279:extraterrestrial hypothesis
10:
1251:
568:Cambridge University Press
272:
253:
182:
29:
558:Peacock, John A. (1998).
425:Bennett, Jeffrey (2017).
135:for, such civilizations.
44:) refers to hypothetical
30:Not to be confused with
1042:Fuller, Curtis (1980).
730:, March 9, 2013, p. 53.
653:"Life, Here and Beyond"
536:10.3390/systems10060254
986:10.1098/rsta.2010.0229
281:is the idea that some
119:is generalized to the
1235:Biological hypotheses
1225:Extraterrestrial life
795:Hollingham, Richard.
385:Quiet and loud aliens
338:Rare Earth hypothesis
333:Extraterrestrial life
53:Copernican Revolution
49:extraterrestrial life
562:Cosmological Physics
427:Life in the universe
117:Copernican principle
1050:. pp. 157–163.
978:2011RSPTA.369..656H
752:on 24 November 2011
706:(in German). Heise.
630:The Washington Post
74:cognitive abilities
940:The New York Times
680:Kardashev, Nikolai
267:Columbian Exchange
972:(1936): 656–668.
657:NASA Astrobiology
436:978-0-13-408908-9
295:, for example by
16:(Redirected from
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933:(18 June 2022).
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343:Cosmic pluralism
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471:"Are we alone?"
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220:U.S. government
205:Arecibo message
187:
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143:Kardashev scale
129:Fermi's Paradox
125:Stephen Hawking
113:
66:
35:
28:
23:
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1106:
1105:; 30 May 2021)
1102:New York Times
1088:
1087:External links
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1023:on 15 May 2013
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254:Main article:
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235:FAST telescope
195:Pioneer plaque
183:Main article:
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162:Drake equation
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88:Poul Anderson
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1230:Intelligence
1197:Solar System
1100:
1073:. Retrieved
1071:. 2023-02-12
1065:
1056:
1048:Warner Books
1046:. New York:
1043:
1037:
1025:. Retrieved
1021:the original
1010:
969:
965:
944:. Retrieved
938:
925:
913:. Retrieved
907:
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886:. Retrieved
882:
873:
862:. Retrieved
858:the original
853:
844:
833:. Retrieved
827:
817:
806:. Retrieved
800:
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779:. Retrieved
765:
754:. Retrieved
750:the original
735:
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691:
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667:
660:. Retrieved
656:
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634:. Retrieved
628:
618:
606:. Retrieved
602:The Guardian
600:
590:
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526:
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502:September 9,
500:. Retrieved
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207:composed by
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149:'s level of
147:civilization
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121:relativistic
114:
104:
102:
92:
77:
67:
64:Intelligence
58:
41:
37:
36:
1185:Outer space
1173:Spaceflight
1068:NWCIowa.edu
746:White House
608:24 February
368:(1997 film)
313:spaceflight
227:Wow! signal
209:Frank Drake
191:Active SETI
111:Probability
46:intelligent
1219:Categories
1097:Adam Frank
1075:2024-07-11
888:2019-02-06
864:2020-11-24
835:2020-11-24
808:2020-11-24
781:2011-11-06
756:2011-11-06
662:3 February
636:January 6,
570:. p.
529:(6): 254.
477:SMH.com.au
412:References
317:New Mexico
307:In culture
213:Carl Sagan
1149:Astronomy
829:Space.com
703:Telepolis
545:2079-8954
497:Space.com
170:Milky Way
103:The term
94:Sentience
1027:21 April
1002:39284787
994:21220289
883:Skeptoid
406:Avi Loeb
390:Sapience
327:See also
133:evidence
82:, being
79:sophoncy
70:sapience
1209:Science
1137:Society
1125:Biology
1111:Portals
1066:Beacon
974:Bibcode
946:19 June
915:15 June
802:BBC.com
523:Systems
366:Contact
273:UFOlogy
96:, like
1000:
992:
578:
543:
433:
288:aliens
173:galaxy
155:energy
1161:Stars
998:S2CID
164:is a
1029:2012
990:PMID
948:2022
917:2022
664:2023
638:2015
610:2012
576:ISBN
541:ISSN
504:2024
431:ISBN
283:UFOs
277:The
244:SETI
225:The
218:The
211:and
160:The
141:The
115:The
84:wise
982:doi
970:369
722:by
682:. "
531:doi
42:ETI
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988:.
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