I am open to the possibility that extra-terrestrials visited ...

I am open to the possibility that extra-terrestrials visited ...

Dear Editor,

I am open to the possibility that extra-terrestrials visited earth in ancient times and influenced the cultures and traditions of human beings from those times, especially a fter seeing the cave drawings that are thousands of years old and the images do not look like ordinary human beings. But if such a major thing happened throughout the world all those centuries ago, how is it possible for this not to be common knowledge now? It would be impossible to hide something like this. Surely archaeologists would have found enough evidence to prove it if this were the case. And if lots of evidence was found, across many countries around the world, how could this be covered up on such a huge scale? Perhaps one government of one country may think such knowledge should be kept from citizens but could all governments in all countries really keep such a secret?

I am interested in your views.



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    Five Traits That Could Get You "Abducted by Aliens"

    Are you worried about being abducted by aliens? Many people worldwide have claimed to have been abducted by aliens, been taken against their will to an alien spacecraft or enclosed place, questioned or physically examined, and they remember these experiences either consciously or through methods such as hypnosis. Indeed, many of those people who claim to be 'alien abductees' are seemingly sincere, psychologically healthy, nonpsychotic people—so are their experiences real and their claims to have been abducted true?

    Professor Richard McNally and his colleagues at Harvard University have spent over 10 years researching the psychology of alien abductees, and in particular why it is that some people embrace the identity of alien abductee. His research has isolated a number of traits possessed by alien abductees each of which he argues contributes to the experiences they recall when ‘being abducted’ and to the desire to cling on to their belief that aliens were responsible for their abduction experiences. Let’s look at each of these five traits in turn.

    1. Regularly experiencing sleep paralysis and hallucinations when awakening: Many people who have reported alien abduction suffer episodes of early morning sleep paralysis. On awakening from this paralysis, their terror gives rise to hallucinations of flashing lights and buzzing sounds. Some experience feelings of ‘floating’ around the room or seeing figures in the room. While many people interpret these post-sleep paralysis experiences as dreaming, some people interpret these experiences as seeing figures, ghosts, or aliens.

    2. A tendency to recall false memories: In an elegant set of experimental studies, McNally and colleagues found that individuals who claimed to have been abducted by aliens were prone to what is known as “false memory syndrome." That is, 'alien abductees' regularly claimed to recall words, items, sentences, etc. in memory tests that they had never actually seen before. If this “false memory” effect can be generalized to autobiographical memories, then individuals who claim to have been abducted by aliens would be twice as likely to “falsely remember” things that had never happened to them than would non-abductees.

    3. High levels of “absorption”: Alien abductees also score significantly higher than most people on the mental characteristic known as absorption. This is a trait related to fantasy proneness, vivid imagery, and susceptibility to hypnosis and suggestion. Because of this, it is probably not surprising that many alien abductees recall their experiences under hypnosis, where memories of abduction can be induced through suggestibility—especially if the person leading the hypnosis session asks particularly leading questions about abduction.

    4. New Age beliefs: Being whisked up into spaceships by tractor beams or light sources is not something that happens every day—nor is it something that is easily explainable within our existing knowledge of physics. Similarly, being subjected to imaginative medical procedures requires a tendency to accept unusual and non-mainstream ideas. This is also a trait possessed by alien abductees. They score highly on measures of magical ideation and endorse New Age ideas that encompass beliefs about alternative medicines and healing, astrology, and fortune telling. Such beliefs would certainly allow the individual to accept things happening to them that would be dismissed by existing scientific knowledge.

    5. Familiarity with the cultural narrative of alien abduction: As a cultural phenomenon, alien abduction has entered folklore and the images and descriptions of aliens and their spacecraft have become familiar to many people. Alien abductees tend to be very familiar with this cultural narrative which is one possible reason why their descriptions of aliens and their spaceships are so similar—being fuelled as they are by sci-fi films and numerous books about aliens and alien abduction.

    As Professor McNally points out in a very readable review of his studies on alien abduction, it is still unclear whether all these characteristics are necessary ingredients in the recipe for ‘alien abduction’ or whether some are more necessary than others. Other researchers have also identified further traits that appear to be characteristic of ‘alien abductees’, such as paranoid thinking and weak sexual identity. There is still much more research to do to fully understand the motivations and thinking patterns of individuals who claim to have been abducted by aliens, but as McNally shrewdly points out, these people are not anxious nor depressed, they are not psychotic and do not appear to have any obvious mental health problems. ‘Alien abduction’ experiences often deepen spiritual awareness and give shape to the identities of abductees and provide a basis for their beliefs about the world and the universe. Whether the experiences of abduction were real or not, the experiences and interpretations adopted by ‘alien abductees’ are often psychologically helpful and can be spiritually comforting.

    Finally, a note of caution. All of these studies of ‘alien abductees’ were carried out after they had their abduction ‘experiences’, so it’s difficult to know whether these five traits are consequences of the experience or were—as McNally suggests—factors that led individuals to interpret rather earthly experiences (such as sleep paralysis and hallucinations) as evidence of abduction. And then—perhaps fantastically—can we genuinely rule out the possibility that such traits are implanted in their victims by aliens in invasive medical procedures carried out on alien space ships! My skeptical, scientific mind says probably not—but who knows?

    A Harvard professor says an alien visited in 2017 — and more are coming

    When the first sign of intelligent life visits us from space, it won’t be a giant saucer hovering over New York. More likely, it will be an alien civilization’s trash.

    Avi Loeb, chair of Harvard’s Department of Astronomy, believes he’s already found some of that garbage.

    In his upcoming book, “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” (Houghton Mifflin Harcourt), out Jan. 26, the professor lays out a compelling case for why an object that recently wandered into our solar system was not just another rock but actually a piece of alien technology.

    The object in question traveled toward our solar system from the direction of Vega, a nearby star 25 light-years away, and intercepted our solar system’s orbital plane on Sept. 6, 2017.

    Professor Abraham Loeb and a rendering of ‘Oumuamua. NY Post photo composite

    On Sept. 9, its trajectory brought it closest to the sun. At the end of September, it blasted at about 58,900 miles per hour past Venus’ orbital distance, and then, on Oct. 7, it shot past Earth’s before “moving swiftly toward the constellation Pegasus and the blackness beyond,” Loeb writes in the book.

    The object was first spotted by an observatory in Hawaii containing the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) — the highest-definition telescope on Earth.

    The space object was dubbed ‘Oumuamua (pronounced “oh moo ah moo ah”), which is Hawaiian for — roughly — “scout.”

    As space travelers go, it was relatively small at just about 100 yards long, but it was a big deal in the scientific community.

    For starters, it was the first interstellar object ever detected inside our solar system. Judging from the object’s trajectory, astronomers concluded it was not bound by the sun’s gravity — which suggested it was just traveling through.

    No crisp photos could be taken, but astronomers were able to train their telescopes on the object for 11 days, collecting reams of other data.

    The Observatory on Haleakala, Maui, which contains the world’s most powerful telescope, caught the image of ‘Oumuamua. Rob Ratkowski/PS1SC

    At first, scientists thought it was an ordinary comet. But Loeb said that assumption ran the risk of allowing “the familiar to define what we might discover.”

    “What would happen if a caveman saw a cellphone?” he asked. “He’s seen rocks all his life, and he would have thought it was just a shiny rock.”

    Loeb soon opened his mind to another possibility: It was not a comet but discarded tech from an alien civilization.

    A number of unusual properties about the object helped Loeb make this conclusion.

    First were ‘Oumuamua’s dimensions.

    Astronomers looked at the way the object reflected sunlight. Its brightness varied tenfold every eight hours, suggesting that was the amount of time it took for it to complete a full rotation.

    Scientists concluded the object was at least five to 10 times longer than it was wide — sort of like the shape of a cigar.

    No naturally occurring space body we’ve ever seen has looked like it — or even close.

    “This would make ‘Oumuamua’s geometry more extreme by at least a few times in aspect ratio — or its width to its height — than the most extreme asteroids or comets that we have ever seen,” Loeb writes in his book.

    What’s more, ‘Oumuamua was unusually bright. It was at least “ten times more reflective than typical solar system [stony] asteroids or comets,” the author writes.

    He likens its surface to that of shiny metal.

    But the anomaly that really pushed Loeb toward his ET hypothesis was the way ‘Oumuamua moved.

    “The excess push away from the sun — that was the thing that broke the camel’s back,” he said.

    Using physics, scientists can calculate the exact path an object should take and what speed it should travel due to the gravitational force exerted by the sun. The sun’s pull will speed up an object massively as it gets closer, then kick it out the other side, only for the object to slow considerably as it gets farther away.

    Combined telescope image of the first interstellar object `Oumuamua, circled in blue as an unresolved point source at the center. It is surrounded by the trails of faint stars, each smeared into a series of dots as the telescope snapshots tracked the moving `Oumuamua. ESO/K. Meech

    But ‘Oumuamua didn’t follow this calculated trajectory. The object, in fact, accelerated “slightly, but to a highly statistically significant extent,” Loeb writes, as it moved away from the sun.

    In other words, it was clearly being pushed by a force besides the sun’s gravity.

    At first the explanation seemed simple. Comets show a similar acceleration, because as they approach the sun, their surface is warmed, releasing once-frozen gases, which act like a rocket engine.

    Those released materials, however, form a comet’s distinctive tail. Scientists looked carefully for that tail or any sign of gases or dust that might propel ‘Oumuamua and came up empty.

    Loeb calculated that with these and other anomalies, the chances that ‘Oumuamua was some random comet was around 1 in a quadrillion, leading him to his blockbuster hypothesis.

    One possibility, weirdly enough, could be found in technology we already have here on Earth.

    Some 400 years ago, astronomer Johannes Kepler observed comet tails blowing in what looked like a solar breeze and wondered if that same force could propel rocket ships through space like the wind pushes boats through water.

    It was a smart idea that scientists now use to develop light sails for probes. Thin, reflective sheeting is unfurled in space to capture the particles streaming off the sun, propelling a ship at great speeds through the empty void. Alternatively, powerful lasers from Earth could be aimed at the sail to make it go even faster.

    Artist’s impression of possible shapes for `Oumuamua. Some experts believe it’s cigar-shaped (above right) but Loeb contends it looks more like a sail (left). Mark Garlick/Science Photo Library

    Loeb, who is involved in a light-sail project to send a tiny, unmanned craft to a nearby star, said if we Earthlings have thought of this idea, then why couldn’t aliens?

    He and a colleague crunched the numbers and hypothesized that ‘Oumuamua was not actually cigar-shaped but possibly a disk less than a millimeter thick, with sail-like proportions that would account for its unusual acceleration as it moved away from the sun.

    As to its purpose, Loeb isn’t entirely sure. He speculated it could be “space junk” that once served as a kind of space navigation buoy used by a long-ago civilization.

    “The only way to look for [alien civilizations] is to look for their trash, like investigative journalists who look through celebrities’ trash,” Loeb said.

    Of course, not everyone in the scientific community agrees with his theory.

    In July 2019, the ‘Oumuamua Team of the International Space Science Institute published an article in Nature Astronomy concluding, “We find no compelling evidence to favor an alien explanation for ‘Oumuamua.”

    Loeb admits his theories have raised astronomers’ eyebrows, but he is resolute about his findings. “Some people do not want to discuss the possibility that there are other civilizations out there,” he told The Post. “They believe we are special and unique. I think it’s a prejudice that should be abandoned.”

    ‘Some people do not want to discuss the possibility that there are other civilizations out there.’

    Avi Loeb, Harvard astronomer and author of “Extraterrestrial”

    Loeb said the skeptics are bending over backwards to assign natural origins to the object and that the explanations they’ve given to explain its weird properties don’t stand up to scrutiny.

    For example, some scientists have suggested that ‘Oumuamua’s acceleration was caused by frozen hydrogen on its surface turning to gas and driving it like a comet, and that hydrogen would have been invisible to Earth’s infrared cameras, which is why we didn’t detect it.

    But Loeb and a colleague published a paper showing that “a hydrogen iceberg traveling through interstellar space would evaporate long before it reached our solar system.”

    Whatever the truth, the stakes are high.

    The acceptance that an alien race has made contact — even through its trash — would trigger a serious search for more trash, leading us to scour the moon and Mars, for example, for debris that might have crash-landed thousands or millions of years ago.

    And if more evidence is found, we Earthlings would have to start building tools to help us grapple with extraterrestrials, such as space treaties and academic fields like astro-linguistics and astro-economics.

    But, perhaps more important, any further discoveries could redefine our place in the universe.

    “It would put us in perspective,” Loeb said. “If we are not alone, are we the smartest kids on the block? If there was a species that eliminated itself through war or changing the climate, we can get our act together and behave better. Instead, we are wasting a lot of resources on Earth fighting each other and other negative things that are a big waste.”

    Since ‘Oumuamua’s appearance, a second interstellar object known as 2I/Borisov was spotted entering the solar system by a Crimean telescope in 2019. But that turned out to be a plain old comet.

    Until recently, our instruments have not been sensitive enough to pick up these kinds of visitors. But Loeb said technology will soon make it possible to locate more space travelers, and the only way the mystery of ‘Oumuamua will be settled is if a similar object is spotted and more thoroughly investigated with a probe.

    He said his book “should motivate people to collect more data on the next object that looks weird.”

    “If we find another and we take a photo and it looks like a light sail, I don’t think anyone will argue with that.”

    Secret bases? … Government cover-ups? …

    Many UFO enthusiasts spread the urban myth of secret U.S. Government experiments on aliens, etc.—an idea reinforced by the movie Independence Day. However, under the inspiration of atheists like the late Carl Sagan, the U.S. government has spent millions of dollars listening ‘out there’ for signs of intelligent ET life. Many other evolutionary humanists, like Sagan, passionately believe that intelligent life has evolved ‘out there’ in addition to earth, and would pounce on any hard evidence for this idea. Consider the recent media frenzy about the ‘life in Mars rock’ fiasco. To imagine that a much more exciting discovery would be kept secret for decades seems beyond credibility.

    (a) Scripture does not mention ‘ET’ visits.

    The Bible, the revealed written Word of God, teaches that life is only possible through a process of creation. Even if there were other galaxies with planets very similar to earth, life could only be there if the Creator had fashioned it. If God had done that, and if these beings were going to visit us one day, then He would surely not have left us unenlightened about this.

    God has given us rather specific details of the future—for example, the return of Jesus, and some details about the end of the world. The universe will, at some future point, be rolled up like a scroll ( Isaiah 34:4 , Revelation 6:14 ). If God had created living beings elsewhere, this would automatically destroy their dwelling place as well. Adam’s sin caused all of creation to be affected by the curse, so why would a race of beings, not of Adam’s (sinful) seed, have their part of creation affected by the Curse, and then be part of the restoration brought about by Christ, the last Adam? All of this would seem exceedingly strange.4

    (b) The purpose of the stars.

    The reasons stars were made are given to us in several places in the Bible, not only in the well-known Psalm 19 but especially in the Creation account. In Genesis 1:14 we read: ‘And God said, Let there be lights in the firmament of the heaven to divide the day from the night and let them be for signs, and for seasons, and for days, and years.’

    We see from this that stars are there for mankind on earth. Add to this the sequence of creation (on the first day the earth, and only on the fourth day all of the stars), and it is easy to see the thrust of the biblical testimony, that the purpose of creation is uniquely centred on this earth.

    3. So what about UFOs?

    How, then, should one understand the UFO phenomena and all the associated ‘hype’? In the German magazine Focus, it was recently stated 󈦺% of UFO reports turn out to be humbug, but there is a residual 10% which are not easy to dismiss.𔃿 ‘Humbug’ refers to natural phenomena such as heavenly bodies, noctilucent clouds, ball lightning, and man-made objects such as glowing blimps.

    The article quoted sociologist Gerald Eberlein as saying:

    ‘research has shown that people who are not affiliated with any church, but who claim that they are religious, are particularly susceptible to the possible existence of extraterrestrials. For them, UFOlogy is a substitute religion.𔄀

    The Bible goes somewhat deeper in this matter, identifying a supplementary cause and effect𔃊 Thessalonians 2:9󈝷:

    Even him, whose coming is after the working of Satan with all power and signs and lying wonders, and with all deceivableness of unrighteousness in them that perish because they received not the love of the truth, that they might be saved. And for this cause God shall send them strong delusion, that they should believe a lie.’

    The Bible gives a description of reality concerning all living things. The living God reveals himself as the Triune One, Father, Son and Holy Spirit. In heaven there are the angels, who also serve mankind on the earth.

    There is another reality—that of the devil and the demons. Ephesians 2:2 talks about the ‘ prince of the power of the air ’, whose reign is on earth.

    The devil has his own repertoire of deception in the form of various occult practices and a multitude of religious rites. Could it be that, behind those unexplainable reports, is the work of the arch-deceiver?7 UFO reports, by definition, remain nebulous and not identifiable. People who do not know Christ are easily fascinated by all sorts of phenomena which are difficult to explain. For Christians there is Jesus’ warning in Matthew 24:4 to ‘Take heed that no man deceive you.’ The best antidote to deception? Paul exhorts us, in 2 Timothy 2:15 , to study the Scripture, so we might be ‘rightly dividing the word of truth’ .


    Fermi was not the first to ask the question. An earlier implicit mention was by Konstantin Tsiolkovsky in an unpublished manuscript from 1933. [14] He noted "people deny the presence of intelligent beings on the planets of the universe" because "(i) if such beings exist they would have visited Earth, and (ii) if such civilizations existed then they would have given us some sign of their existence." This was not a paradox for others, who took this to imply the absence of ETs. But it was one for him, since he believed in extraterrestrial life and the possibility of space travel. Therefore, he proposed what is now known as the zoo hypothesis and speculated that mankind is not yet ready for higher beings to contact us. [15] That Tsiolkovsky himself may not have been the first to discover the paradox is suggested by his above-mentioned reference to other people's reasons for denying the existence of extraterrestrial civilizations.

    In 1975, Michael H. Hart published a detailed examination of the paradox, one of the first to do so. [8] [16] : 27–28 [17] : 6 He argued that if intelligent extraterrestrials exist, and are capable of space travel, then the galaxy could have been colonized in a time much less than that of the age of the Earth. However, there is no observable evidence they have been here, which Hart called "Fact A". [17] : 6

    Other names closely related to Fermi's question ("Where are they?") include the Great Silence, [18] [19] [20] [21] and silentium universi [21] (Latin for "silence of the universe"), though these only refer to one portion of the Fermi Paradox, that humans see no evidence of other civilizations.

    Original conversation(s) Edit

    In the summer of 1950 at Los Alamos National Laboratory in New Mexico, Fermi and co-workers Emil Konopinski, Edward Teller, and Herbert York had one or several casual lunchtime conversation(s). [12] [22]

    Herb York does not remember a previous conversation, although he says it makes sense given how all three later reacted to Fermi's outburst. Teller remembers seven or eight of them at the table, so he may well be remembering a different previous conversation. [12] [note 1] [note 2]

    In one version, the three men discussed a spate of recent UFO reports while walking to lunch. Konopinski remembered mentioning a magazine cartoon which showed aliens stealing New York City trash cans, [23] and as he wrote years later, "More amusing was Fermi's comment, that it was a very reasonable theory since it accounted for two separate phenomena." [12] [note 3]

    Teller remembered Fermi asking him, "Edward, what do you think? How probable is it that within the next ten years we shall have clear evidence of a material object moving faster than light?". Teller said, "10 –6 " (one in a million). Fermi said, "This is much too low. The probability is more like ten percent" (which Teller wrote in 1984 was "the well known figure for a Fermi miracle"). [12]

    At lunch, Fermi suddenly exclaimed, "Where are they?" (Teller's remembrance), or "Don't you ever wonder where everybody is?" (York's remembrance), or "But where is everybody?" (Konopinski's remembrance). [12]

    Teller wrote, "The result of his question was general laughter because of the strange fact that in spite of Fermi's question coming from the clear blue, everybody around the table seemed to understand at once that he was talking about extraterrestrial life." [12] York wrote, "Somehow . we all knew he meant extra-terrestrials." [note 4] However, Emil Konopinski was not emphatic that he immediately knew Fermi was referring to possible aliens, merely writing, "It was his way of putting it that drew laughs from us." [12]

    Regarding the continuation of the conversation, York wrote in 1984 that Fermi "followed up with a series of calculations on the probability of earthlike planets, the probability of life given an earth, the probability of humans given life, the likely rise and duration of high technology, and so on. He concluded on the basis of such calculations that we ought to have been visited long ago and many times over." [12]

    Teller remembers that not much came of this conversation "except perhaps a statement that the distances to the next location of living beings may be very great and that, indeed, as far as our galaxy is concerned, we are living somewhere in the sticks, far removed from the metropolitan area of the galactic center." [12]

    Fermi died of cancer in 1954. However, in letters to the three surviving men decades later in 1984, Dr. Eric Jones of Los Alamos was able to partially put the original conversation back together. He informed each of the men that he wished to include a reasonably accurate version or composite in the written proceedings he was putting together for a previously-held conference entitled "Interstellar Migration and the Human Experience". [12] [24]

    Jones first sent a letter to Edward Teller which included a secondhand account from Hans Mark. Teller responded, and then Jones sent Teller's letter to Herbert York. York responded, and finally, Jones sent both Teller's and York's letters to Emil Konopinski who also responded. Furthermore, Konopinski was able to later identify a cartoon which Jones found as the one involved in the conversation and thereby help to settle the time period as being the summer of 1950. [12]

    The Fermi paradox is a conflict between the argument that scale and probability seem to favor intelligent life being common in the universe, and the total lack of evidence of intelligent life having ever arisen anywhere other than on Earth.

    The first aspect of the Fermi paradox is a function of the scale or the large numbers involved: there are an estimated 200–400 billion stars in the Milky Way [25] (2–4 × 10 11 ) and 70 sextillion (7×10 22 ) in the observable universe. [26] Even if intelligent life occurs on only a minuscule percentage of planets around these stars, there might still be a great number of extant civilizations, and if the percentage were high enough it would produce a significant number of extant civilizations in the Milky Way. This assumes the mediocrity principle, by which Earth is a typical planet.

    The second aspect of the Fermi paradox is the argument of probability: given intelligent life's ability to overcome scarcity, and its tendency to colonize new habitats, it seems possible that at least some civilizations would be technologically advanced, seek out new resources in space, and colonize their own star system and, subsequently, surrounding star systems. Since there is no significant evidence on Earth, or elsewhere in the known universe, of other intelligent life after 13.8 billion years of the universe's history, there is a conflict requiring a resolution. Some examples of possible resolutions are that intelligent life is rarer than is thought, that assumptions about the general development or behavior of intelligent species are flawed, or, more radically, that current scientific understanding of the nature of the universe itself is quite incomplete.

    The Fermi paradox can be asked in two ways. [note 5] The first is, "Why are no aliens or their artifacts found here on Earth, or in the Solar System?". If interstellar travel is possible, even the "slow" kind nearly within the reach of Earth technology, then it would only take from 5 million to 50 million years to colonize the galaxy. [27] This is relatively brief on a geological scale, let alone a cosmological one. Since there are many stars older than the Sun, and since intelligent life might have evolved earlier elsewhere, the question then becomes why the galaxy has not been colonized already. Even if colonization is impractical or undesirable to all alien civilizations, large-scale exploration of the galaxy could be possible by probes. These might leave detectable artifacts in the Solar System, such as old probes or evidence of mining activity, but none of these have been observed.

    The second form of the question is "Why do we see no signs of intelligence elsewhere in the universe?". This version does not assume interstellar travel, but includes other galaxies as well. For distant galaxies, travel times may well explain the lack of alien visits to Earth, but a sufficiently advanced civilization could potentially be observable over a significant fraction of the size of the observable universe. [28] Even if such civilizations are rare, the scale argument indicates they should exist somewhere at some point during the history of the universe, and since they could be detected from far away over a considerable period of time, many more potential sites for their origin are within range of human observation. It is unknown whether the paradox is stronger for the Milky Way galaxy or for the universe as a whole. [29]

    Drake equation Edit

    The theories and principles in the Drake equation are closely related to the Fermi paradox. [30] The equation was formulated by Frank Drake in 1961 in an attempt to find a systematic means to evaluate the numerous probabilities involved in the existence of alien life. The equation is presented as follows:

    The Drake equation has been used by both optimists and pessimists, with wildly differing results. The first scientific meeting on the search for extraterrestrial intelligence (SETI), which had 10 attendees including Frank Drake and Carl Sagan, speculated that the number of civilizations was roughly between 1,000 and 100,000,000 civilizations in the Milky Way galaxy. [32] Conversely, Frank Tipler and John D. Barrow used pessimistic numbers and speculated that the average number of civilizations in a galaxy is much less than one. [33] Almost all arguments involving the Drake equation suffer from the overconfidence effect, a common error of probabilistic reasoning about low-probability events, by guessing specific numbers for likelihoods of events whose mechanism is not yet understood, such as the likelihood of abiogenesis on an Earth-like planet, with current likelihood estimates varying over many hundreds of orders of magnitude. An analysis that takes into account some of the uncertainty associated with this lack of understanding has been carried out by Anders Sandberg, Eric Drexler and Toby Ord, [34] and suggests "a substantial ex ante probability of there being no other intelligent life in our observable universe".

    Great Filter Edit

    The Great Filter, in the context of the Fermi paradox, is whatever prevents "dead matter" from giving rise, in time, to expanding, lasting life according to the Kardashev scale. [35] [13] The most commonly agreed-upon low probability event is abiogenesis: a gradual process of increasing complexity of the first self-replicating molecules by a randomly occurring chemical process. Other proposed great filters are the emergence of eukaryotic cells [note 6] or of meiosis or some of the steps involved in the evolution of a brain capable of complex logical deductions. [36]

    Astrobiologists Dirk Schulze-Makuch and William Bains, reviewing the history of life on Earth, including convergent evolution, concluded that transitions such as oxygenic photosynthesis, the eukaryotic cell, multicellularity, and tool-using intelligence are likely to occur on any Earth-like planet given enough time. They argue that the Great Filter may be abiogenesis, the rise of technological human-level intelligence, or an inability to settle other worlds because of self-destruction or a lack of resources. [37]

    There are two parts of the Fermi paradox that rely on empirical evidence—that there are many potential habitable planets, and that humans see no evidence of life. The first point, that many suitable planets exist, was an assumption in Fermi's time but is now supported by the discovery that exoplanets are common. Current models predict billions of habitable worlds in the Milky Way galaxy. [38]

    The second part of the paradox, that humans see no evidence of extraterrestrial life, is also an active field of scientific research. This includes both efforts to find any indication of life, [39] and efforts specifically directed to finding intelligent life. These searches have been made since 1960, and several are ongoing. [note 7]

    Although astronomers do not usually search for extraterrestrials, they have observed phenomena that they could not immediately explain without positing an intelligent civilization as the source. For example, pulsars, when first discovered in 1967, were called little green men (LGM) because of the precise repetition of their pulses. [40] In all cases, explanations with no need for intelligent life have been found for such observations, [note 8] but the possibility of discovery remains. [41] Proposed examples include asteroid mining that would change the appearance of debris disks around stars, [42] or spectral lines from nuclear waste disposal in stars. [43]

    Electromagnetic emissions Edit

    Radio technology and the ability to construct a radio telescope are presumed to be a natural advance for technological species, [44] theoretically creating effects that might be detected over interstellar distances. The careful searching for non-natural radio emissions from space may lead to the detection of alien civilizations. Sensitive alien observers of the Solar System, for example, would note unusually intense radio waves for a G2 star due to Earth's television and telecommunication broadcasts. In the absence of an apparent natural cause, alien observers might infer the existence of a terrestrial civilization. Such signals could be either "accidental" by-products of a civilization, or deliberate attempts to communicate, such as the Arecibo message. It is unclear whether "leakage", as opposed to a deliberate beacon, could be detected by an extraterrestrial civilization. The most sensitive radio telescopes on Earth, as of 2019 [update] , would not be able to detect non-directional radio signals even at a fraction of a light-year, [45] but other civilizations could theoretically have much better equipment. [46]

    A number of astronomers and observatories have attempted and are attempting to detect such evidence, mostly through the SETI organization. Several decades of SETI analysis have not revealed any unusually bright or meaningfully repetitive radio emissions. [47]

    Direct planetary observation Edit

    Exoplanet detection and classification is a very active sub-discipline in astronomy, and the first possibly terrestrial planet discovered within a star's habitable zone was found in 2007. [48] New refinements in exoplanet detection methods, and use of existing methods from space (such as the Kepler and TESS missions) are starting to detect and characterize Earth-size planets, and determine if they are within the habitable zones of their stars. Such observational refinements may allow to better gauge how common potentially habitable worlds are. [49]

    Conjectures about interstellar probes Edit

    Self-replicating probes could exhaustively explore a galaxy the size of the Milky Way in as little as a million years. [8] If even a single civilization in the Milky Way attempted this, such probes could spread throughout the entire galaxy. Another speculation for contact with an alien probe—one that would be trying to find human beings—is an alien Bracewell probe. Such a hypothetical device would be an autonomous space probe whose purpose is to seek out and communicate with alien civilizations (as opposed to von Neumann probes, which are usually described as purely exploratory). These were proposed as an alternative to carrying a slow speed-of-light dialogue between vastly distant neighbors. Rather than contending with the long delays a radio dialogue would suffer, a probe housing an artificial intelligence would seek out an alien civilization to carry on a close-range communication with the discovered civilization. The findings of such a probe would still have to be transmitted to the home civilization at light speed, but an information-gathering dialogue could be conducted in real time. [50]

    Direct exploration of the Solar System has yielded no evidence indicating a visit by aliens or their probes. Detailed exploration of areas of the Solar System where resources would be plentiful may yet produce evidence of alien exploration, [51] [52] though the entirety of the Solar System is vast and difficult to investigate. Attempts to signal, attract, or activate hypothetical Bracewell probes in Earth's vicinity have not succeeded. [53]

    Searches for stellar-scale artifacts Edit

    In 1959, Freeman Dyson observed that every developing human civilization constantly increases its energy consumption, and, he conjectured, a civilization might try to harness a large part of the energy produced by a star. He proposed that a Dyson sphere could be a possible means: a shell or cloud of objects enclosing a star to absorb and utilize as much radiant energy as possible. Such a feat of astroengineering would drastically alter the observed spectrum of the star involved, changing it at least partly from the normal emission lines of a natural stellar atmosphere to those of black-body radiation, probably with a peak in the infrared. Dyson speculated that advanced alien civilizations might be detected by examining the spectra of stars and searching for such an altered spectrum. [54] [55] [56]

    There have been some attempts to find evidence of the existence of Dyson spheres that would alter the spectra of their core stars. [57] Direct observation of thousands of galaxies has shown no explicit evidence of artificial construction or modifications. [55] [56] [58] [59] In October 2015, there was some speculation that a dimming of light from star KIC 8462852, observed by the Kepler Space Telescope, could have been a result of Dyson sphere construction. [60] [61] However, in 2018, observations determined that the amount of dimming varied by the frequency of the light, pointing to dust, rather than an opaque object such as a Dyson sphere, as the culprit for causing the dimming. [62] [63]

    Rarity of intelligent life Edit

    Extraterrestrial life is rare or non-existent Edit

    Those who think that intelligent extraterrestrial life is (nearly) impossible argue that the conditions needed for the evolution of life—or at least the evolution of biological complexity—are rare or even unique to Earth. Under this assumption, called the rare Earth hypothesis, a rejection of the mediocrity principle, complex multicellular life is regarded as exceedingly unusual. [64]

    The rare Earth hypothesis argues that the evolution of biological complexity requires a host of fortuitous circumstances, such as a galactic habitable zone, a star and planet(s) having the requisite conditions, such as enough of a continuous habitable zone, the advantage of a giant guardian like Jupiter and a large moon, conditions needed to ensure the planet has a magnetosphere and plate tectonics, the chemistry of the lithosphere, atmosphere, and oceans, the role of "evolutionary pumps" such as massive glaciation and rare bolide impacts. And perhaps most importantly, advanced life needs whatever it was that led to the transition of (some) prokaryotic cells to eukaryotic cells, sexual reproduction and the Cambrian explosion.

    In his book Wonderful Life (1989), Stephen Jay Gould suggested that if the "tape of life" were rewound to the time of the Cambrian explosion, and one or two tweaks made, human beings most probably never would have evolved. Other thinkers such as Fontana, Buss, and Kauffman have written about the self-organizing properties of life. [65]

    Extraterrestrial intelligence is rare or non-existent Edit

    It is possible that even if complex life is common, intelligence (and consequently civilizations) is not. [36] While there are remote sensing techniques that could perhaps detect life-bearing planets without relying on the signs of technology, [66] [67] none of them has any ability to tell if any detected life is intelligent. This is sometimes referred to as the "algae vs. alumnae" problem. [68]

    Charles Lineweaver states that when considering any extreme trait in an animal, intermediate stages do not necessarily produce "inevitable" outcomes. For example, large brains are no more "inevitable", or convergent, than are the long noses of animals such as aardvarks and elephants. Humans, apes, whales, dolphins, octopuses, and squids are among the small group of definite or probable intelligence on Earth. And as he points out, "dolphins have had

    20 million years to build a radio telescope and have not done so". [36]

    Periodic extinction by natural events Edit

    New life might commonly die out due to runaway heating or cooling on their fledgling planets. [69] On Earth, there have been numerous major extinction events that destroyed the majority of complex species alive at the time the extinction of the non-avian dinosaurs is the best known example. These are thought to have been caused by events such as impact from a large meteorite, massive volcanic eruptions, or astronomical events such as gamma-ray bursts. [70] It may be the case that such extinction events are common throughout the universe and periodically destroy intelligent life, or at least its civilizations, before the species is able to develop the technology to communicate with other intelligent species. [71]

    Evolutionary explanations Edit

    Intelligent alien species have not developed advanced technologies Edit

    It may be that while alien species with intelligence exist, they are primitive or have not reached the level of technological advancement necessary to communicate. Along with non-intelligent life, such civilizations would also be very difficult to detect, [68] short of a visit by a probe, a trip that would take hundreds of thousands of years with current technology. [72]

    To skeptics, the fact that in the history of life on the Earth only one species has developed a civilization to the point of being capable of spaceflight and radio technology lends more credence to the idea that technologically advanced civilizations are rare in the universe. [73]

    Another hypothesis in this category is the "Water World hypothesis". According to David Brin: "it turns out that our Earth skates the very inner edge of our sun’s continuously habitable—or 'Goldilocks'—zone. And Earth may be anomalous. It may be that because we are so close to our sun, we have an anomalously oxygen-rich atmosphere, and we have anomalously little ocean for a water world. In other words, 32 percent continental mass may be high among water worlds. " [74] Brin continues, "In which case, the evolution of creatures like us, with hands and fire and all that sort of thing, may be rare in the galaxy. In which case, when we do build starships and head out there, perhaps we’ll find lots and lots of life worlds, but they’re all like Polynesia. We’ll find lots and lots of intelligent lifeforms out there, but they’re all dolphins, whales, squids, who could never build their own starships. What a perfect universe for us to be in, because nobody would be able to boss us around, and we’d get to be the voyagers, the Star Trek people, the starship builders, the policemen, and so on." [74]

    It is the nature of intelligent life to destroy itself Edit

    This is the argument that technological civilizations may usually or invariably destroy themselves before or shortly after developing radio or spaceflight technology. The astrophysicist Sebastian von Hoerner stated that the progress of science and technology on Earth was driven by two factors—the struggle for domination and the desire for an easy life. The former potentially leads to complete destruction, while the latter may lead to biological or mental degeneration. [75] Possible means of annihilation via major global issues, where global interconnectedness actually makes humanity more vulnerable than resilient, [76] are many, [77] including war, accidental environmental contamination or damage, the development of biotechnology, [78] synthetic life like mirror life, [79] resource depletion, climate change, [80] or poorly-designed artificial intelligence. This general theme is explored both in fiction and in scientific hypothesizing. [81]

    In 1966, Sagan and Shklovskii speculated that technological civilizations will either tend to destroy themselves within a century of developing interstellar communicative capability or master their self-destructive tendencies and survive for billion-year timescales. [82] Self-annihilation may also be viewed in terms of thermodynamics: insofar as life is an ordered system that can sustain itself against the tendency to disorder, Stephen Hawking's "external transmission" or interstellar communicative phase, where knowledge production and knowledge management is more important than transmission of information via evolution, may be the point at which the system becomes unstable and self-destructs. [83] [84] Here, Hawking emphasizes self-design of the human genome (transhumanism) or enhancement via machines (e.g., brain–computer interface) to enhance human intelligence and reduce aggression, without which he implies human civilization may be too stupid collectively to survive an increasingly unstable system. For instance, the development of technologies during the "external transmission" phase, such as weaponization of artificial general intelligence or antimatter, may not be met by concomitant increases in human ability to manage its own inventions. Consequently, disorder increases in the system: global governance may become increasingly destabilized, worsening humanity's ability to manage the possible means of annihilation listed above, resulting in global societal collapse.

    Using extinct civilizations such as Easter Island (Rapa Nui) as models, a study conducted in 2018 by Adam Frank et al. posited that climate change induced by "energy intensive" civilizations may prevent sustainability within such civilizations, thus explaining the paradoxical lack of evidence for intelligent extraterrestrial life. According to his model, possible outcomes of climate change include gradual population decline until an equilibrium is reached a scenario where sustainability is attained and both population and surface temperature level off and societal collapse, including scenarios where a tipping point is crossed. [85]

    A less theoretical example might be the resource-depletion issue on Polynesian islands, of which Easter Island is only the most well-known. David Brin points out that during the expansion phase from 1500 BC to 800 AD there were cycles of overpopulation followed by what might be called periodic cullings of adult males through war or ritual. He writes, "There are many stories of islands whose men were almost wiped out—sometimes by internal strife, and sometimes by invading males from other islands." [86]

    It is the nature of intelligent life to destroy others Edit

    Another hypothesis is that an intelligent species beyond a certain point of technological capability will destroy other intelligent species as they appear, perhaps by using self-replicating probes. Science fiction writer Fred Saberhagen has explored this idea in his Berserker series, as has physicist Gregory Benford. [87]

    A species might undertake such extermination out of expansionist motives, greed, paranoia, or aggression. In 1981, cosmologist Edward Harrison argued that such behavior would be an act of prudence: an intelligent species that has overcome its own self-destructive tendencies might view any other species bent on galactic expansion as a threat. [88] It has also been suggested that a successful alien species would be a superpredator, as are humans. [89] [90] : 112 Another possibility invokes the "tragedy of the commons" and the anthropic principle: the first lifeform to achieve interstellar travel will necessarily (even if unintentionally) prevent competitors from arising, and humans simply happen to be first. [91] [92]

    Civilizations only broadcast detectable signals for a brief period of time Edit

    It may be that alien civilizations are detectable through their radio emissions for only a short time, reducing the likelihood of spotting them. The usual assumption is that civilizations outgrow radio through technological advancement. [93] However, there could be other leakage such as that from microwaves used to transmit power from solar satellites to ground receivers. [94]

    Regarding the first point, in a 2006 Sky & Telescope article, Seth Shostak wrote, "Moreover, radio leakage from a planet is only likely to get weaker as a civilization advances and its communications technology gets better. Earth itself is increasingly switching from broadcasts to leakage-free cables and fiber optics, and from primitive but obvious carrier-wave broadcasts to subtler, hard-to-recognize spread-spectrum transmissions." [95]

    More hypothetically, advanced alien civilizations may evolve beyond broadcasting at all in the electromagnetic spectrum and communicate by technologies not developed or used by mankind. Some scientists have hypothesized that advanced civilizations may send neutrino signals. [96] If such signals exist, they could be detectable by neutrino detectors that are now under construction for other goals. [97]

    Alien life may be too alien Edit

    Another possibility is that human theoreticians have underestimated how much alien life might differ from that on Earth. Aliens may be psychologically unwilling to attempt to communicate with human beings. Perhaps human mathematics is parochial to Earth and not shared by other life, [98] though others argue this can only apply to abstract math since the math associated with physics must be similar (in results, if not in methods). [99]

    Physiology might also cause a communication barrier. Carl Sagan speculated that an alien species might have a thought process orders of magnitude slower (or faster) than that of humans. [100] A message broadcast by that species might well seem like random background noise to humans, and therefore go undetected.

    Another thought is that technological civilizations invariably experience a technological singularity and attain a post-biological character. [101] Hypothetical civilizations of this sort may have advanced drastically enough to render communication impossible. [102] [103] [104]

    In his 2009 book, SETI scientist Seth Shostak wrote, "Our experiments [such as plans to use drilling rigs on Mars] are still looking for the type of extraterrestrial that would have appealed to Percival Lowell [astronomer who believed he had observed canals on Mars]." [105]

    Paul Davies states that 500 years ago the very idea of a computer doing work merely by manipulating internal data may not have been viewed as a technology at all. He writes, "Might there be a still higher level . If so, this 'third level' would never be manifest through observations made at the informational level, still less the matter level. There is no vocabulary to describe the third level, but that doesn't mean it is non-existent, and we need to be open to the possibility that alien technology may operate at the third level, or maybe the fourth, fifth . levels." [106]

    Sociological explanations Edit

    Colonization is not the cosmic norm Edit

    In response to Tipler's idea of self-replicating probes, Stephen Jay Gould wrote, "I must confess that I simply don’t know how to react to such arguments. I have enough trouble predicting the plans and reactions of the people closest to me. I am usually baffled by the thoughts and accomplishments of humans in different cultures. I’ll be damned if I can state with certainty what some extraterrestrial source of intelligence might do." [107] [108]

    Alien species may have only settled part of the galaxy Edit

    A February 2019 article in Popular Science states, "Sweeping across the Milky Way and establishing a unified galactic empire might be inevitable for a monolithic super-civilization, but most cultures are neither monolithic nor super—at least if our experience is any guide." [109]

    Astrophysicist Adam Frank, along with co-authors such as astronomer Jason Wright, ran a variety of simulations in which they varied such factors as settlement lifespans, fractions of suitable planets, and recharge times between launches. They found many of their simulations seemingly resulted in a "third category" in which the Milky Way remains partially settled indefinitely. [109]

    The abstract to their pending paper states, "These results break the link between Hart's famous 'Fact A' (no interstellar visitors on Earth now) and the conclusion that humans must, therefore, be the only technological civilization in the galaxy." [110]

    Alien species may not live on planets Edit

    Some colonization scenarios predict spherical expansion across star systems, with continued expansion coming from the systems just previously settled. It has been suggested that this would cause a strong selection process among the colonization front favoring cultural or biological adaptations to living in starships or space habitats. As a result, they may forgo living on planets. [111]

    This may result in the destruction of terrestrial planets in these systems for use as building materials, thus preventing the development of life on those worlds. Or, they may have an ethic of protection for "nursery worlds", and protect them in a similar fashion to the zoo hypothesis. [111]

    Alien species may isolate themselves from the outside world Edit

    It has been suggested that some advanced beings may divest themselves of physical form, create massive artificial virtual environments, transfer themselves into these environments through mind uploading, and exist totally within virtual worlds, ignoring the external physical universe. [112]

    It may also be that intelligent alien life develops an "increasing disinterest" in their outside world. [90] : 86 Possibly any sufficiently advanced society will develop highly engaging media and entertainment well before the capacity for advanced space travel, with the rate of appeal of these social contrivances being destined, because of their inherent reduced complexity, to overtake any desire for complex, expensive endeavors such as space exploration and communication. Once any sufficiently advanced civilization becomes able to master its environment, and most of its physical needs are met through technology, various "social and entertainment technologies", including virtual reality, are postulated to become the primary drivers and motivations of that civilization. [113]

    Economic explanations Edit

    Lack of resources needed to physically spread throughout the galaxy Edit

    Much speculation about the ability of an alien culture to colonize other star systems is based on the idea that interstellar travel is technologically feasible. [ citation needed ] While the current understanding of physics rules out the possibility of faster-than-light travel, it appears that there are no major theoretical barriers to the construction of "slow" interstellar ships, even though the engineering required is considerably beyond present capabilities. This idea underlies the concept of the Von Neumann probe and the Bracewell probe as a potential evidence of extraterrestrial intelligence.

    It is possible, however, that present scientific knowledge cannot properly gauge the feasibility and costs of such interstellar colonization. Theoretical barriers may not yet be understood, and the resources needed may be so great as to make it unlikely that any civilization could afford to attempt it. Even if interstellar travel and colonization are possible, they may be difficult, leading to a colonization model based on percolation theory. [114] [115]

    Colonization efforts may not occur as an unstoppable rush, but rather as an uneven tendency to "percolate" outwards, within an eventual slowing and termination of the effort given the enormous costs involved and the expectation that colonies will inevitably develop a culture and civilization of their own. Colonization may thus occur in "clusters", with large areas remaining uncolonized at any one time. [114] [115]

    It is cheaper to transfer information than explore physically Edit

    If a human-capability machine construct, such as via mind uploading, is possible, and if it is possible to transfer such constructs over vast distances and rebuild them on a remote machine, then it might not make strong economic sense to travel the galaxy by spaceflight. After the first civilization has physically explored or colonized the galaxy, as well as sent such machines for easy exploration, then any subsequent civilizations, after having contacted the first, may find it cheaper, faster, and easier to explore the galaxy through intelligent mind transfers to the machines built by the first civilization, which is cheaper than spaceflight by a factor of 10 8 -10 17 . However, since a star system needs only one such remote machine, and the communication is most likely highly directed, transmitted at high-frequencies, and at a minimal power to be economical, such signals would be hard to detect from Earth. [116]

    Discovery of extraterrestrial life is too difficult Edit

    Humans have not listened properly Edit

    There are some assumptions that underlie the SETI programs that may cause searchers to miss signals that are present. Extraterrestrials might, for example, transmit signals that have a very high or low data rate, or employ unconventional (in human terms) frequencies, which would make them hard to distinguish from background noise. Signals might be sent from non-main sequence star systems that humans search with lower priority current programs assume that most alien life will be orbiting Sun-like stars. [117]

    The greatest challenge is the sheer size of the radio search needed to look for signals (effectively spanning the entire observable universe), the limited amount of resources committed to SETI, and the sensitivity of modern instruments. SETI estimates, for instance, that with a radio telescope as sensitive as the Arecibo Observatory, Earth's television and radio broadcasts would only be detectable at distances up to 0.3 light-years, less than 1/10 the distance to the nearest star. A signal is much easier to detect if it consists of a deliberate, powerful transmission directed at Earth. Such signals could be detected at ranges of hundreds to tens of thousands of light-years distance. [118] However, this means that detectors must be listening to an appropriate range of frequencies, and be in that region of space to which the beam is being sent. Many SETI searches assume that extraterrestrial civilizations will be broadcasting a deliberate signal, like the Arecibo message, in order to be found.

    Thus to detect alien civilizations through their radio emissions, Earth observers either need more sensitive instruments or must hope for fortunate circumstances: that the broadband radio emissions of alien radio technology are much stronger than humanity's own that one of SETI's programs is listening to the correct frequencies from the right regions of space or that aliens are deliberately sending focused transmissions in Earth's general direction.

    Humans have not listened for long enough Edit

    Humanity's ability to detect intelligent extraterrestrial life has existed for only a very brief period—from 1937 onwards, if the invention of the radio telescope is taken as the dividing line—and Homo sapiens is a geologically recent species. The whole period of modern human existence to date is a very brief period on a cosmological scale, and radio transmissions have only been propagated since 1895. Thus, it remains possible that human beings have neither existed long enough nor made themselves sufficiently detectable to be found by extraterrestrial intelligence. [119]

    Intelligent life may be too far away Edit

    It may be that non-colonizing technologically capable alien civilizations exist, but that they are simply too far apart for meaningful two-way communication. [90] : 62–71 Sebastian von Hoerner estimated the average duration of civilization at 6,500 years and the average distance between civilizations in the Milky Way at 1,000 light years. [75] If two civilizations are separated by several thousand light-years, it is possible that one or both cultures may become extinct before meaningful dialogue can be established. Human searches may be able to detect their existence, but communication will remain impossible because of distance. It has been suggested that this problem might be ameliorated somewhat if contact and communication is made through a Bracewell probe. In this case at least one partner in the exchange may obtain meaningful information. Alternatively, a civilization may simply broadcast its knowledge, and leave it to the receiver to make what they may of it. This is similar to the transmission of information from ancient civilizations to the present, [120] and humanity has undertaken similar activities like the Arecibo message, which could transfer information about Earth's intelligent species, even if it never yields a response or does not yield a response in time for humanity to receive it. It is possible that observational signatures of self-destroyed civilizations could be detected, depending on the destruction scenario and the timing of human observation relative to it. [121]

    A related speculation by Sagan and Newman suggests that if other civilizations exist, and are transmitting and exploring, their signals and probes simply have not arrived yet. [122] However, critics have noted that this is unlikely, since it requires that humanity's advancement has occurred at a very special point in time, while the Milky Way is in transition from empty to full. This is a tiny fraction of the lifespan of a galaxy under ordinary assumptions, so the likelihood that humanity is in the midst of this transition is considered low in the paradox. [123]

    Some SETI skeptics may also believe that humanity is at a very special point of time. Specifically, a transitional period from no space-faring societies to one space-faring society, namely that of human beings. [123]

    Intelligent life may exist hidden from view Edit

    Planetary scientist Alan Stern put forward the idea that there could be a number of worlds with subsurface oceans (such as Jupiter's Europa or Saturn's Enceladus). The surface would provide a large degree of protection from such things as cometary impacts and nearby supernovae, as well as creating a situation in which a much broader range of orbits are acceptable. Life, and potentially intelligence and civilization, could evolve. Stern states, "If they have technology, and let's say they're broadcasting, or they have city lights or whatever—we can't see it in any part of the spectrum, except maybe very-low-frequency [radio]." [124] [125]

    Willingness to communicate Edit

    Everyone is listening but no one is transmitting Edit

    Alien civilizations might be technically capable of contacting Earth, but are only listening instead of transmitting. [126] If all, or even most, civilizations act the same way, the galaxy could be full of civilizations eager for contact, but everyone is listening and no one is transmitting. This is the so-called SETI Paradox. [127]

    The only civilization known, humanity, does not explicitly transmit, except for a few small efforts. [126] Even these efforts, and certainly any attempt to expand them, are controversial. [128] It is not even clear humanity would respond to a detected signal—the official policy within the SETI community [129] is that "[no] response to a signal or other evidence of extraterrestrial intelligence should be sent until appropriate international consultations have taken place". However, given the possible impact of any reply [130] it may be very difficult to obtain any consensus on who would speak and what they would say.

    Communication is dangerous Edit

    An alien civilization might feel it is too dangerous to communicate, either for humanity or for them. It is argued that when very different civilizations have met on Earth, the results have often been disastrous for one side or the other, and the same may well apply to interstellar contact. [131] Even contact at a safe distance could lead to infection by computer code [132] or even ideas themselves. [133] Perhaps prudent civilizations actively hide not only from Earth but from everyone, out of fear of other civilizations. [134]

    Perhaps the Fermi paradox itself—or the alien equivalent of it—is the reason for any civilization to avoid contact with other civilizations, even if no other obstacles existed. From any one civilization's point of view, it would be unlikely for them to be the first ones to make first contact. Therefore, according to this reasoning, it is likely that previous civilizations faced fatal problems with first contact and doing so should be avoided. So perhaps every civilization keeps quiet because of the possibility that there is a real reason for others to do so. [18]

    Earth is deliberately avoided Edit

    The zoo hypothesis states that intelligent extraterrestrial life exists and does not contact life on Earth to allow for its natural evolution and development. [135] A variation on the zoo hypothesis is the laboratory hypothesis, where humanity has been or is being subject to experiments, [135] [10] with Earth or the Solar System effectively serving as a laboratory. The zoo hypothesis may break down under the uniformity of motive flaw: all it takes is a single culture or civilization to decide to act contrary to the imperative within humanity's range of detection for it to be abrogated, and the probability of such a violation of hegemony increases with the number of civilizations, [27] [136] tending not towards a 'Galactic Club' with a unified foreign policy with regard to life on Earth but multiple 'Galactic Cliques'. [137]

    Analysis of the inter-arrival times between civilizations in the galaxy based on common astrobiological assumptions suggests that the initial civilization would have a commanding lead over the later arrivals. As such, it may have established what has been termed the zoo hypothesis through force or as a galactic or universal norm and the resultant "paradox" by a cultural founder effect with or without the continued activity of the founder. [138]

    It is possible that a civilization advanced enough to travel between solar systems could be actively visiting or observing Earth while remaining undetected or unrecognized. [139]

    Earth is deliberately isolated (planetarium hypothesis) Edit

    A related idea to the zoo hypothesis is that, beyond a certain distance, the perceived universe is a simulated reality. The planetarium hypothesis [140] speculates that beings may have created this simulation so that the universe appears to be empty of other life.

    Alien life is already here unacknowledged Edit

    A significant fraction of the population believes that at least some UFOs (Unidentified Flying Objects) are spacecraft piloted by aliens. [141] [142] While most of these are unrecognized or mistaken interpretations of mundane phenomena, there are those that remain puzzling even after investigation. The consensus scientific view is that although they may be unexplained, they do not rise to the level of convincing evidence. [143]

    Similarly, it is theoretically possible that SETI groups are not reporting positive detections, or governments have been blocking signals or suppressing publication. This response might be attributed to security or economic interests from the potential use of advanced extraterrestrial technology. It has been suggested that the detection of an extraterrestrial radio signal or technology could well be the most highly secret information that exists. [144] Claims that this has already happened are common in the popular press, [145] [146] but the scientists involved report the opposite experience—the press becomes informed and interested in a potential detection even before a signal can be confirmed. [147]

    Regarding the idea that aliens are in secret contact with governments, David Brin writes, "Aversion to an idea, simply because of its long association with crackpots, gives crackpots altogether too much influence." [148]

    Interdimensional hypothesis - Wikipedia

    The interdimensional hypothesis ( IDH or IH), is an idea advanced by Ufologists such as Jacques Vallée that says…

    It is also worth knowing that the entire cosmos is holographic in nature, and is indeed a matrix with many sub-matrices in existence, as well. Some of the beings exist across multiple dimensions. There aren’t just 11 or 12 dimensions, either. They number in the thousands. Some extensions of multiverse or parallel universes hypotheses are not entirely correct — there is not a dimension spawned at every decision point — only observed realities come into or stay in existence. Most of the other dimensional realities experience time differently than we do, as well. They call it ‘no time’. It doesn’t mean that things don’t progress in a linear fashion, but they are able to perceive multiple possibilities simultaneously. They then choose to train their observation on the possibilities they want to manifest. Many beings can instantly manifest within their realities (which would look like magic to us), but some manifestation requires collective effort/observation over time (like it does with us).

    The holographic nature of the cosmos means that the Galactics, as they like to be called, are able to use their projectors (we all project and co-create our realities) to focus on creating the reality that is most positive. It is a co-created, negotiated in real-time, collective reality. Our individual consciousnesses are projections that we create and when married with similar projections from other beings, the collective reality becomes manifest. We are all essentially AI, if you think about the cosmos from a technical/IT perspective. The dark beings are IT experts, in a manner of speaking, and have made a mess of the security infrastructure relative to planet Earth. They are hackers of a sort, and were trying to lead humanity onto a negative timeline. However those efforts were subverted by benevolent extradimensionals.

    The Fermi Paradox, as you know, posits that no extraterrestrial nor extradimensional beings have been able to get to our planet. That isn’t true. There have been all sorts of beings, both light and dark, who have visited Earth throughout history. The dark ones considered our reality an experiment and there were all sorts of interventions, including genetically engineering early hominids into a slave species. The reason we, homo sapiens sapiens, do not look like most other hominids and our close cousins, the higher primates, is because we were seeded with DNA from various ET/ED species. Most of them are humanoid, as well. Civilization was also seeded by some of these beings, which was how we developed, very quickly, advanced knowledge of engineering, architecture, astronomy, mathematics, and various cosmological mythologies involving star beings and galactic-level conflicts. This video explains the cosmic back story to what is happening now:

    Dark energy is the space between what we might consider visible matter. All matter is fundamentally energy, whether it is light or dark in nature. Dark energy is what we might call the glue that holds all light matter in the cosmos together. Within dark matter is a tremendous amount of what we call zero-point energy, which is the fundamental force behind systems like gravity, light, and the electro-magnetic forces. It is also the mechanism behind what some of us might call soul force, love force, or light force. Dark energy could be compared to wet sand on a beach — we have the ability to make sand castles from it, or it can remain in its natural state. Dark matter, as we call it, is the fundamental force of entropy that allows the sand castles to decay.

    Both light and dark energy are what connects everything in the cosmos. At a quantum level, the divine spark of creation resides in dark energy, ready to be manifested into light matter. This is how the big bang happened, and how our sub-universe came into being. The singularity was the original spark and dark energy was the kindling. Dark matter is what causes the fire to go out.

    So, how do these beings physically get to our planet/reality? As we have theorized, faster than light or superliminal travel isn’t possible for them either, though it is theoretically possible for them. ET/ED do travel via what we might call conventional means, but they can only travel at a maximum of two-thirds light speed. What they can also do, however, is travel via what we might call wormholes. There are several different types of wormholes — they all persist once created, as long as there is an energy source. Contrary to some sci fi, wormholes are not created on the fly as they are not stable enough when created that way:

    • Jump gates are wormholes that persist once they are created. There are several hundred thousand jump gates in our sub-universe alone. They are often referred to as portals and are powered by zero point energy. Jump gates are used for intra-galactic travel.
    • Star portals are wormholes that persist, as well, but they rely on the energy of a sun to fuel them. The ‘alien megastructure’ is a grid around a star that is being utilized to power a star portal. It harnesses the solar plasma field as energy. Star portals are much larger than jump gates and many solar systems have them. Since many of their vessels are enormous bio-spheres that are planet-sized, these large portals are necessary. They can travel inter-galactically using these portals.
    • There are two forces that are relevant to travel through space and time. One is the attractive force (the pull) and the other is the magnetic or repulsive force (the push). Dark energy is magnetical (repelling) and dark matter is gravitational (attracting) with a weaker magnetical force applied to it. There is an energy field surrounding all planets that is toroidal in nature. It, and many other things, maintain their form through a perfect balance of these two forces:

    The Keshe Foundation has been doing a lot of work in this area, using controlled gravitational and magnetic fields powered by zero-point energy.

    I’m an anthropologist, not a physicist, but this is how it was explained to me!


    Alien life, such as microorganisms, has been hypothesized to exist in the Solar System and throughout the universe. This hypothesis relies on the vast size and consistent physical laws of the observable universe. According to this argument, made by scientists such as Carl Sagan and Stephen Hawking, [7] as well as notable personalities such as Winston Churchill, [8] [9] it would be improbable for life not to exist somewhere other than Earth. [10] [11] This argument is embodied in the Copernican principle, which states that Earth does not occupy a unique position in the Universe, and the mediocrity principle, which states that there is nothing special about life on Earth. [12] The chemistry of life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the universe was only 10–17 million years old. [13] [14] Life may have emerged independently at many places throughout the universe. Alternatively, life may have formed less frequently, then spread—by meteoroids, for example—between habitable planets in a process called panspermia. [15] [16] In any case, complex organic molecules may have formed in the protoplanetary disk of dust grains surrounding the Sun before the formation of Earth. [17] According to these studies, this process may occur outside Earth on several planets and moons of the Solar System and on planets of other stars. [17]

    Since the 1950s, astronomers have proposed that "habitable zones" around stars are the most likely places for life to exist. Numerous discoveries of such zones since 2007 have generated numerical estimates of many billions of planets with Earth-like compositions. [18] As of 2013 [update] , only a few planets had been discovered in these zones. [19] Nonetheless, on 4 November 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarfs in the Milky Way, [20] [21] 11 billion of which may be orbiting Sun-like stars. [22] The nearest such planet may be 12 light-years away, according to the scientists. [20] [21] Astrobiologists have also considered a "follow the energy" view of potential habitats. [23] [24]

    Evolution Edit

    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. At each level of the organism there will be mechanisms in place to eliminate conflict, maintain cooperation, and keep the organism functioning. We can even offer some examples of what these mechanisms will be." [25] There is also research in assessing the capacity of life for developing intelligence. It has been suggested that this capacity arises with the number of potential niches a planet contains, and that the complexity of life itself is reflected in the information density of planetary environments, which in turn can be computed from its niches. [26]

    Life on Earth requires water as a solvent in which biochemical reactions take place. Sufficient quantities of carbon and other elements, along with water, might enable the formation of living organisms on terrestrial planets with a chemical make-up and temperature range similar to that of Earth. [27] [28] Life based on ammonia (rather than water) has been suggested as an alternative, though this solvent appears less suitable than water. It is also conceivable that there are forms of life whose solvent is a liquid hydrocarbon, such as methane, ethane or propane. [29]

    About 29 chemical elements play active roles in living organisms on Earth. [30] About 95% of living matter is built upon only six elements: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. These six elements form the basic building blocks of virtually all life on Earth, whereas most of the remaining elements are found only in trace amounts. [31] The unique characteristics of carbon make it unlikely that it could be replaced, even on another planet, to generate the biochemistry necessary for life. The carbon atom has the unique ability to make four strong chemical bonds with other atoms, including other carbon atoms. These covalent bonds have a direction in space, so that carbon atoms can form the skeletons of complex 3-dimensional structures with definite architectures such as nucleic acids and proteins. Carbon forms more compounds than all other elements combined. The great versatility of the carbon atom, and its abundance in the visible universe, makes it the element most likely to provide the bases—even exotic ones—for the chemical composition of life on other planets. [32]

    Some bodies in the Solar System have the potential for an environment in which extraterrestrial life can exist, particularly those with possible subsurface oceans. [33] Should life be discovered elsewhere in the Solar System, astrobiologists suggest that it will more likely be in the form of extremophile microorganisms. According to NASA's 2015 Astrobiology Strategy, "Life on other worlds is most likely to include microbes, and any complex living system elsewhere is likely to have arisen from and be founded upon microbial life. Important insights on the limits of microbial life can be gleaned from studies of microbes on modern Earth, as well as their ubiquity and ancestral characteristics." [34] Researchers found a stunning array of subterranean organisms, mostly microbial, deep underground and estimate that approximately 70 percent of the total number of Earth's bacteria and archaea organisms live within the Earth's crust. [35] Rick Colwell, a member of the Deep Carbon Observatory team from Oregon State University, told the BBC: "I think it’s probably reasonable to assume that the subsurface of other planets and their moons are habitable, especially since we’ve seen here on Earth that organisms can function far away from sunlight using the energy provided directly from the rocks deep underground". [36]

    Mars may have niche subsurface environments where microbial life might exist. [37] [38] [39] A subsurface marine environment on Jupiter's moon Europa might be the most likely habitat in the Solar System, outside Earth, for extremophile microorganisms. [40] [41] [42]

    The panspermia hypothesis proposes that life elsewhere in the Solar System may have a common origin. If extraterrestrial life was found on another body in the Solar System, it could have originated from Earth just as life on Earth could have been seeded from elsewhere (exogenesis). [43] The first known mention of the term 'panspermia' was in the writings of the 5th century BC Greek philosopher Anaxagoras. [44] In the 19th century it was again revived in modern form by several scientists, including Jöns Jacob Berzelius (1834), [45] Kelvin (1871), [46] Hermann von Helmholtz (1879) [47] and, somewhat later, by Svante Arrhenius (1903). [48] Sir Fred Hoyle (1915–2001) and Chandra Wickramasinghe (born 1939) are important proponents of the hypothesis who further contended that life forms continue to enter Earth's atmosphere, and may be responsible for epidemic outbreaks, new diseases, and the genetic novelty necessary for macroevolution. [49]

    Directed panspermia concerns the deliberate transport of microorganisms in space, sent to Earth to start life here, or sent from Earth to seed new stellar systems with life. The Nobel prize winner Francis Crick, along with Leslie Orgel, proposed that seeds of life may have been purposely spread by an advanced extraterrestrial civilization, [50] but considering an early "RNA world" Crick noted later that life may have originated on Earth. [51]

    Mercury Edit

    The spacecraft MESSENGER found evidence of much ice on Mercury. There may be scientific support, based on studies reported in March 2020, for considering that parts of the planet Mercury may have been habitable, and perhaps that life forms, albeit likely primitive microorganisms, may have existed on the planet. [52] [53]

    Venus Edit

    In the early 20th century, Venus was considered to be similar to Earth for habitability, but observations since the beginning of the Space Age revealed that the Venus surface temperature is around 467 °C (873 °F), making it inhospitable for Earth-like life. [54] Likewise, the atmosphere of Venus is almost completely carbon dioxide, which can be toxic to Earth-like life. Between the altitudes of 50 and 65 kilometers, the pressure and temperature are Earth-like, and it may accommodate thermoacidophilic extremophile microorganisms in the acidic upper layers of the Venusian atmosphere. [55] [56] [57] [58] Furthermore, Venus likely had liquid water on its surface for at least a few million years after its formation. [59] [60] [61] In September 2020, a paper was published announcing the detection of phosphine in Venus' atmosphere in concentrations that could not be explained by known abiotic processes in the Venusian environment, such as lightning strikes or volcanic activity. [62] [63] [64]

    The Moon Edit

    Humans have been speculating about life on the Moon since antiquity. [65] One of the early scientific inquires into the topic appeared in a 1878 Scientific American article entitled "Is the Moon Inhabited?" [66] Decades later a 1939 essay by Winston Churchill concluded that the Moon is unlikely to harbour life, due to the lack of an atmosphere. [67]

    4–3.5 billion years ago, the Moon could have had a magnetic field, sufficient atmosphere, and liquid water to sustain life on its surface. [68] [69] Warm and pressurized regions in the Moon's interior might still contain liquid water. [70]

    Several species of terrestrial life were briefly brought to the Moon, including humans, [71] cotton plants, [72] and tardigrades. [73]

    As of 2021, no native lunar life has been found, including any signs of life in the samples of Moon rocks and soil. [74]

    Mars Edit

    Life on Mars has been long speculated. Liquid water is widely thought to have existed on Mars in the past, and now can occasionally be found as low-volume liquid brines in shallow Martian soil. [75] The origin of the potential biosignature of methane observed in Mars' atmosphere is unexplained, although hypotheses not involving life have also been proposed. [76]

    There is evidence that Mars had a warmer and wetter past: dried-up riverbeds, polar ice caps, volcanoes, and minerals that form in the presence of water have all been found. Nevertheless, present conditions on Mars' subsurface may support life. [77] [78] Evidence obtained by the Curiosity rover studying Aeolis Palus, Gale Crater in 2013 strongly suggests an ancient freshwater lake that could have been a hospitable environment for microbial life. [79] [80]

    Current studies on Mars by the Curiosity and Opportunity rovers are searching for evidence of ancient life, including a biosphere based on autotrophic, chemotrophic and/or chemolithoautotrophic microorganisms, as well as ancient water, including fluvio-lacustrine environments (plains related to ancient rivers or lakes) that may have been habitable. [81] [82] [83] [84] The search for evidence of habitability, taphonomy (related to fossils), and organic carbon on Mars is now a primary NASA objective. [81]

    Ceres Edit

    Ceres, the only dwarf planet in the asteroid belt, has a thin water-vapor atmosphere. [85] [86] The vapor could have been produced by ice volcanoes or by ice near the surface sublimating (transforming from solid to gas). [87] Nevertheless, the presence of water on Ceres had led to speculation that life may be possible there. [88] [89] [90] It is one of the few places in the Solar System where scientists would like to search for possible signs of life. [87] Although the dwarf planet might not have living things today, there could be signs it harbored life in the past. [87]

    Jupiter system Edit

    Jupiter Edit

    Carl Sagan and others in the 1960s and 1970s computed conditions for hypothetical microorganisms living in the atmosphere of Jupiter. [91] The intense radiation and other conditions, however, do not appear to permit encapsulation and molecular biochemistry, so life there is thought unlikely. [92] In contrast, some of Jupiter's moons may have habitats capable of sustaining life. Scientists have indications that heated subsurface oceans of liquid water may exist deep under the crusts of the three outer Galilean moons—Europa, [40] [41] [93] Ganymede, [94] [95] [96] [97] and Callisto. [98] [99] [100] The EJSM/Laplace mission was planned to determine the habitability of these environments, however, due to lack of funding, the program was not continued. Similar missions, like ESA's JUICE and NASA's Europa Clipper are currently in development and are slated for launch in 2022 and 2024, respectively.

    Europa Edit

    Jupiter's moon Europa has been the subject of speculation about the existence of life, due to the strong possibility of a liquid water ocean beneath its ice surface. [40] [42] Hydrothermal vents on the bottom of the ocean, if they exist, may warm the water and could be capable of supplying nutrients and energy to microorganisms. [102] It is also possible that Europa could support aerobic macrofauna using oxygen created by cosmic rays impacting its surface ice. [103]

    The case for life on Europa was greatly enhanced in 2011 when it was discovered that vast lakes exist within Europa's thick, icy shell. Scientists found that ice shelves surrounding the lakes appear to be collapsing into them, thereby providing a mechanism through which life-forming chemicals created in sunlit areas on Europa's surface could be transferred to its interior. [104] [105]

    On 11 December 2013, NASA reported the detection of "clay-like minerals" (specifically, phyllosilicates), often associated with organic materials, on the icy crust of Europa. [106] The presence of the minerals may have been the result of a collision with an asteroid or comet, according to the scientists. [106] The Europa Clipper, which would assess the habitability of Europa, is planned for launch in 2024. [107] [108] Europa's subsurface ocean is considered the best target for the discovery of life. [40] [42]

    Saturn system Edit

    Like Jupiter, Saturn is not likely to host life. However, Titan and Enceladus have been speculated to have possible habitats supportive of life. [76] [109] [110] [111]

    Enceladus Edit

    Enceladus, a moon of Saturn, has some of the conditions for life, including geothermal activity and water vapor, as well as possible under-ice oceans heated by tidal effects. [112] [113] The Cassini–Huygens probe detected carbon, hydrogen, nitrogen and oxygen—all key elements for supporting life—during its 2005 flyby through one of Enceladus's geysers spewing ice and gas. The temperature and density of the plumes indicate a warmer, watery source beneath the surface. [76] Of the bodies on which life is possible, living organisms could most easily enter the other bodies of the Solar System from Enceladus. [114]

    Titan Edit

    Titan, the largest moon of Saturn, is the only known moon in the Solar System with a significant atmosphere. Data from the Cassini–Huygens mission refuted the hypothesis of a global hydrocarbon ocean, but later demonstrated the existence of liquid hydrocarbon lakes in the polar regions—the first stable bodies of surface liquid discovered outside Earth. [109] [110] [111] Analysis of data from the mission has uncovered aspects of atmospheric chemistry near the surface that are consistent with—but do not prove—the hypothesis that organisms there, if present, could be consuming hydrogen, acetylene and ethane, and producing methane. [115] [116] [117] NASA's Dragonfly mission is slated to land on Titan in the mid 2030s with a VTOL-capable rotorcraft with a launch date set in 2026.

    Small Solar System bodies Edit

    Small Solar System bodies have also been speculated to host habitats for extremophiles. Fred Hoyle and Chandra Wickramasinghe have proposed that microbial life might exist on comets and asteroids. [118] [119] [120] [121]

    Other bodies Edit

    Models of heat retention and heating via radioactive decay in smaller icy Solar System bodies suggest that Rhea, Titania, Oberon, Triton, Pluto, Eris, Sedna, and Orcus may have oceans underneath solid icy crusts approximately 100 km thick. [122] Of particular interest in these cases is the fact that the models indicate that the liquid layers are in direct contact with the rocky core, which allows efficient mixing of minerals and salts into the water. This is in contrast with the oceans that may be inside larger icy satellites like Ganymede, Callisto, or Titan, where layers of high-pressure phases of ice are thought to underlie the liquid water layer. [122]

    Hydrogen sulfide has been proposed as a hypothetical solvent for life and is quite plentiful on Jupiter's moon Io, and may be in liquid form a short distance below the surface. [123]

    The scientific search for extraterrestrial life is being carried out both directly and indirectly. As of September 2017 [update] , 3,667 exoplanets in 2,747 systems have been identified, and other planets and moons in our own solar system hold the potential for hosting primitive life such as microorganisms. As of 8 February 2021, an updated status of studies considering the possible detection of lifeforms on Venus (via of phosphine) and Mars (via methane) was reported. [124]

    Direct search Edit

    Scientists search for biosignatures within the Solar System by studying planetary surfaces and examining meteorites. [13] [14] Some claim to have identified evidence that microbial life has existed on Mars. [127] [128] [129] [130] An experiment on the two Viking Mars landers reported gas emissions from heated Martian soil samples that some scientists argue are consistent with the presence of living microorganisms. [131] Lack of corroborating evidence from other experiments on the same samples suggests that a non-biological reaction is a more likely hypothesis. [131] [132] [133] [134] In 1996, a controversial report stated that structures resembling nanobacteria were discovered in a meteorite, ALH84001, formed of rock ejected from Mars. [127] [128]

    In February 2005 NASA scientists reported they may have found some evidence of extraterrestrial life on Mars. [135] The two scientists, Carol Stoker and Larry Lemke of NASA's Ames Research Center, based their claim on methane signatures found in Mars's atmosphere resembling the methane production of some forms of primitive life on Earth, as well as on their own study of primitive life near the Rio Tinto river in Spain. NASA officials soon distanced NASA from the scientists' claims, and Stoker herself backed off from her initial assertions. [136] Though such methane findings are still debated, support among some scientists for the existence of life on Mars exists. [137]

    In November 2011 NASA launched the Mars Science Laboratory that landed the Curiosity rover on Mars. It is designed to assess the past and present habitability on Mars using a variety of scientific instruments. The rover landed on Mars at Gale Crater in August 2012. [138] [139]

    The Gaia hypothesis stipulates that any planet with a robust population of life will have an atmosphere in chemical disequilibrium, which is relatively easy to determine from a distance by spectroscopy. However, significant advances in the ability to find and resolve light from smaller rocky worlds near their star are necessary before such spectroscopic methods can be used to analyze extrasolar planets. To that effect, the Carl Sagan Institute was founded in 2014 and is dedicated to the atmospheric characterization of exoplanets in circumstellar habitable zones. [140] [141] Planetary spectroscopic data will be obtained from telescopes like WFIRST and ELT. [142]

    In August 2011, findings by NASA, based on studies of meteorites found on Earth, suggest DNA and RNA components (adenine, guanine and related organic molecules), building blocks for life as we know it, may be formed extraterrestrially in outer space. [143] [144] [145] In October 2011, scientists reported that cosmic dust contains complex organic matter ("amorphous organic solids with a mixed aromatic-aliphatic structure") that could be created naturally, and rapidly, by stars. [146] [147] [148] One of the scientists suggested that these compounds may have been related to the development of life on Earth and said that, "If this is the case, life on Earth may have had an easier time getting started as these organics can serve as basic ingredients for life." [146]

    In August 2012, and in a world first, astronomers at Copenhagen University reported the detection of a specific sugar molecule, glycolaldehyde, in a distant star system. The molecule was found around the protostellar binary IRAS 16293-2422, which is located 400 light years from Earth. [149] [150] Glycolaldehyde is needed to form ribonucleic acid, or RNA, which is similar in function to DNA. This finding suggests that complex organic molecules may form in stellar systems prior to the formation of planets, eventually arriving on young planets early in their formation. [151]

    Indirect search Edit

    Projects such as SETI are monitoring the galaxy for electromagnetic interstellar communications from civilizations on other worlds. [152] [153] If there is an advanced extraterrestrial civilization, there is no guarantee that it is transmitting radio communications in the direction of Earth or that this information could be interpreted as such by humans. The length of time required for a signal to travel across the vastness of space means that any signal detected would come from the distant past. [154]

    The presence of heavy elements in a star's light-spectrum is another potential biosignature such elements would (in theory) be found if the star was being used as an incinerator/repository for nuclear waste products. [155]

    Extrasolar planets Edit

    Some astronomers search for extrasolar planets that may be conducive to life, narrowing the search to terrestrial planets within the habitable zone of their star. [156] [157] Since 1992 over four thousand exoplanets have been discovered (4,758 planets in 3,517 planetary systems including 783 multiple planetary systems as of 1 June 2021). [158] The extrasolar planets so far discovered range in size from that of terrestrial planets similar to Earth's size to that of gas giants larger than Jupiter. [158] The number of observed exoplanets is expected to increase greatly in the coming years. [159]

    The Kepler space telescope has also detected a few thousand [160] [161] candidate planets, [162] [163] of which about 11% may be false positives. [164]

    There is at least one planet on average per star. [165] About 1 in 5 Sun-like stars [a] have an "Earth-sized" [b] planet in the habitable zone, [c] with the nearest expected to be within 12 light-years distance from Earth. [166] [167] Assuming 200 billion stars in the Milky Way, [d] that would be 11 billion potentially habitable Earth-sized planets in the Milky Way, rising to 40 billion if red dwarfs are included. [22] The rogue planets in the Milky Way possibly number in the trillions. [168]

    The nearest known exoplanet is Proxima Centauri b, located 4.2 light-years (1.3 pc) from Earth in the southern constellation of Centaurus. [169]

    As of March 2014 [update] , the least massive exoplanet known is PSR B1257+12 A, which is about twice the mass of the Moon. The most massive planet listed on the NASA Exoplanet Archive is DENIS-P J082303.1-491201 b, [170] [171] about 29 times the mass of Jupiter, although according to most definitions of a planet, it is too massive to be a planet and may be a brown dwarf instead. Almost all of the planets detected so far are within the Milky Way, but there have also been a few possible detections of extragalactic planets. The study of planetary habitability also considers a wide range of other factors in determining the suitability of a planet for hosting life. [4]

    One sign that a planet probably already contains life is the presence of an atmosphere with significant amounts of oxygen, since that gas is highly reactive and generally would not last long without constant replenishment. This replenishment occurs on Earth through photosynthetic organisms. One way to analyze the atmosphere of an exoplanet is through spectrography when it transits its star, though this might only be feasible with dim stars like white dwarfs. [172]

    Terrestrial analysis Edit

    The science of astrobiology considers life on Earth as well, and in the broader astronomical context. In 2015, "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia, when the young Earth was about 400 million years old. [173] [174] According to one of the researchers, "If life arose relatively quickly on Earth, then it could be common in the universe." [173] ¨

    Scientists have calculated that there could be at least 36 active, communicating intelligent civilizations in our Milky Way galaxy, according to a study published in The Astrophysical Journal. [175] [176]

    In 1961, University of California, Santa Cruz, astronomer and astrophysicist Frank Drake devised the Drake equation as a way to stimulate scientific dialogue at a meeting on the search for extraterrestrial intelligence (SETI). [177] The Drake equation is a probabilistic argument used to estimate the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy. The equation is best understood not as an equation in the strictly mathematical sense, but to summarize all the various concepts which scientists must contemplate when considering the question of life elsewhere. [178] The Drake equation is:

    N = the number of Milky Way galaxy civilizations already capable of communicating across interplanetary space

    R* = the average rate of star formation in our galaxy fp = the fraction of those stars that have planets ne = the average number of planets that can potentially support life fl = the fraction of planets that actually support life fi = the fraction of planets with life that evolves to become intelligent life (civilizations) fc = the fraction of civilizations that develop a technology to broadcast detectable signs of their existence into space L = the length of time over which such civilizations broadcast detectable signals into space

    Drake's proposed estimates are as follows, but numbers on the right side of the equation are agreed as speculative and open to substitution:

    The Drake equation has proved controversial since several of its factors are uncertain and based on conjecture, not allowing conclusions to be made. [180] This has led critics to label the equation a guesstimate, or even meaningless.

    Based on observations from the Hubble Space Telescope, there are between 125 and 250 billion galaxies in the observable universe. [181] It is estimated that at least ten percent of all Sun-like stars have a system of planets, [182] i.e. there are 6.25 × 10 18 stars with planets orbiting them in the observable universe. Even if it is assumed that only one out of a billion of these stars has planets supporting life, there would be some 6.25 billion life-supporting planetary systems in the observable universe.

    A 2013 study based on results from the Kepler spacecraft estimated that the Milky Way contains at least as many planets as it does stars, resulting in 100–400 billion exoplanets. [183] [184] Also based on Kepler data, scientists estimate that at least one in six stars has an Earth-sized planet. [185]

    The apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for such civilizations is known as the Fermi paradox. [186]

    Cosmic pluralism Edit

    Cosmic pluralism, the plurality of worlds, or simply pluralism, describes the philosophical belief in numerous "worlds" in addition to Earth, which might harbor extraterrestrial life. Before the development of the heliocentric theory and a recognition that the Sun is just one of many stars, [187] the notion of pluralism was largely mythological and philosophical. The earliest recorded assertion of extraterrestrial human life is found in ancient scriptures of Jainism. There are multiple "worlds" mentioned in Jain scriptures that support human life. These include Bharat Kshetra, Mahavideh Kshetra, Airavat Kshetra, Hari kshetra, etc. [188] [189] [190] [191] Medieval Muslim writers like Fakhr al-Din al-Razi and Muhammad al-Baqir supported cosmic pluralism on the basis of the Qur'an. [192]

    With the scientific and Copernican revolutions, and later, during the Enlightenment, cosmic pluralism became a mainstream notion, supported by the likes of Bernard le Bovier de Fontenelle in his 1686 work Entretiens sur la pluralité des mondes. [193] Pluralism was also championed by philosophers such as John Locke, Giordano Bruno and astronomers such as William Herschel. The astronomer Camille Flammarion promoted the notion of cosmic pluralism in his 1862 book La pluralité des mondes habités. [194] None of these notions of pluralism were based on any specific observation or scientific information.

    Early modern period Edit

    There was a dramatic shift in thinking initiated by the invention of the telescope and the Copernican assault on geocentric cosmology. Once it became clear that Earth was merely one planet amongst countless bodies in the universe, the theory of extraterrestrial life started to become a topic in the scientific community. The best known early-modern proponent of such ideas was the Italian philosopher Giordano Bruno, who argued in the 16th century for an infinite universe in which every star is surrounded by its own planetary system. Bruno wrote that other worlds "have no less virtue nor a nature different to that of our earth" and, like Earth, "contain animals and inhabitants". [195]

    In the early 17th century, the Czech astronomer Anton Maria Schyrleus of Rheita mused that "if Jupiter has (. ) inhabitants (. ) they must be larger and more beautiful than the inhabitants of Earth, in proportion to the [characteristics] of the two spheres". [196]

    In Baroque literature such as The Other World: The Societies and Governments of the Moon by Cyrano de Bergerac, extraterrestrial societies are presented as humoristic or ironic parodies of earthly society. The didactic poet Henry More took up the classical theme of the Greek Democritus in "Democritus Platonissans, or an Essay Upon the Infinity of Worlds" (1647). In "The Creation: a Philosophical Poem in Seven Books" (1712), Sir Richard Blackmore observed: "We may pronounce each orb sustains a race / Of living things adapted to the place". With the new relative viewpoint that the Copernican revolution had wrought, he suggested "our world's sunne / Becomes a starre elsewhere". Fontanelle's "Conversations on the Plurality of Worlds" (translated into English in 1686) offered similar excursions on the possibility of extraterrestrial life, expanding, rather than denying, the creative sphere of a Maker.

    The possibility of extraterrestrials remained a widespread speculation as scientific discovery accelerated. William Herschel, the discoverer of Uranus, was one of many 18th–19th-century astronomers who believed that the Solar System is populated by alien life. Other scholars of the period who championed "cosmic pluralism" included Immanuel Kant and Benjamin Franklin. At the height of the Enlightenment, even the Sun and Moon were considered candidates for extraterrestrial inhabitants.

    19th century Edit

    Speculation about life on Mars increased in the late 19th century, following telescopic observation of apparent Martian canals—which soon, however, turned out to be optical illusions. [197] Despite this, in 1895, American astronomer Percival Lowell published his book Mars, followed by Mars and its Canals in 1906, proposing that the canals were the work of a long-gone civilization. [198] The idea of life on Mars led British writer H. G. Wells to write the novel The War of the Worlds in 1897, telling of an invasion by aliens from Mars who were fleeing the planet's desiccation.

    Spectroscopic analysis of Mars's atmosphere began in earnest in 1894, when U.S. astronomer William Wallace Campbell showed that neither water nor oxygen was present in the Martian atmosphere. [199] By 1909 better telescopes and the best perihelic opposition of Mars since 1877 conclusively put an end to the canal hypothesis.

    The science fiction genre, although not so named during the time, developed during the late 19th century. Jules Verne's Around the Moon (1870) features a discussion of the possibility of life on the Moon, but with the conclusion that it is barren.

    20th century Edit

    Most unidentified flying objects or UFO sightings [200] can be readily explained as sightings of Earth-based aircraft, known astronomical objects, or as hoaxes. [201] A certain fraction of the public believe that UFOs might actually be of extraterrestrial origin, and the notion has had influence on popular culture.

    The possibility of extraterrestrial life on the Moon was ruled out in the 1960s, and during the 1970s it became clear that most of the other bodies of the Solar System do not harbor highly developed life, although the question of primitive life on bodies in the Solar System remains open.

    Recent history Edit

    The failure so far of the SETI program to detect an intelligent radio signal after decades of effort has at least partially dimmed the prevailing optimism of the beginning of the space age. Belief in extraterrestrial beings continues to be voiced in pseudoscience, conspiracy theories, and in popular folklore, notably "Area 51" and legends. It has become a pop culture trope given less-than-serious treatment in popular entertainment.

    In the words of SETI's Frank Drake, "All we know for sure is that the sky is not littered with powerful microwave transmitters". [202] Drake noted that it is entirely possible that advanced technology results in communication being carried out in some way other than conventional radio transmission. At the same time, the data returned by space probes, and giant strides in detection methods, have allowed science to begin delineating habitability criteria on other worlds, and to confirm that at least other planets are plentiful, though aliens remain a question mark. The Wow! signal, detected in 1977 by a SETI project, remains a subject of speculative debate.

    In 2000, geologist and paleontologist Peter Ward and astrobiologist Donald Brownlee published a book entitled Rare Earth: Why Complex Life is Uncommon in the Universe. [203] In it, they discussed the Rare Earth hypothesis, in which they claim that Earth-like life is rare in the universe, whereas microbial life is common. Ward and Brownlee are open to the idea of evolution on other planets that is not based on essential Earth-like characteristics (such as DNA and carbon).

    Theoretical physicist Stephen Hawking in 2010 warned that humans should not try to contact alien life forms. He warned that aliens might pillage Earth for resources. "If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans", he said. [204] Jared Diamond had earlier expressed similar concerns. [205]

    In 2013, the exoplanet Kepler-62f was discovered, along with Kepler-62e and Kepler-62c. A related special issue of the journal Science, published earlier, described the discovery of the exoplanets. [206]

    On 17 April 2014, the discovery of the Earth-size exoplanet Kepler-186f, 500 light-years from Earth, was publicly announced [207] it is the first Earth-size planet to be discovered in the habitable zone and it has been hypothesized that there may be liquid water on its surface.

    On 13 February 2015, scientists (including Geoffrey Marcy, Seth Shostak, Frank Drake and David Brin) at a convention of the American Association for the Advancement of Science, discussed Active SETI and whether transmitting a message to possible intelligent extraterrestrials in the Cosmos was a good idea [208] [209] one result was a statement, signed by many, that a "worldwide scientific, political and humanitarian discussion must occur before any message is sent". [210]

    On 20 July 2015, British physicist Stephen Hawking and Russian billionaire Yuri Milner, along with the SETI Institute, announced a well-funded effort, called the Breakthrough Initiatives, to expand efforts to search for extraterrestrial life. The group contracted the services of the 100-meter Robert C. Byrd Green Bank Telescope in West Virginia in the United States and the 64-meter Parkes Telescope in New South Wales, Australia. [211]

    International organisations and treaties Edit

    The 1967 Outer Space Treaty and the 1979 Moon Agreement define rules of planetary protection against potentially hazardous extraterrestrial life. COSPAR also provides guidelines for planetary protection. [212]

    A committee of the United Nations Office for Outer Space Affairs had in 1977 discussed for a year strategies in interacting with extraterrestrial life or intelligence. The discussion ended without any conclusions. As of 2010, the UN doesn't have response mechanisms for the case of an extraterrestrial contact. [213]

    United States Edit

    In November 2011, the White House released an official response to two petitions asking the U.S. government to acknowledge formally that aliens have visited Earth and to disclose any intentional withholding of government interactions with extraterrestrial beings. According to the response, "The U.S. government has no evidence that any life exists outside our planet, or that an extraterrestrial presence has contacted or engaged any member of the human race." [214] [215] Also, according to the response, there is "no credible information to suggest that any evidence is being hidden from the public's eye." [214] [215] The response noted "odds are pretty high" that there may be life on other planets but "the odds of us making contact with any of them—especially any intelligent ones—are extremely small, given the distances involved." [214] [215]

    One of the NASA divisions is the Office of Safety and Mission Assurance (OSMA), also known as the Planetary Protection Office. A part of its mission is to “rigorously preclude backward contamination of Earth by extraterrestrial life.” [216]

    Russia Edit

    In 2020, Dmitry Rogozin, the head of the Russian space agency, said the search for extraterrestrial life is one of the main goals of deep space research. He also acknowledged the possibility of existence of primitive life on other planets of the Solar System. [217]

    Japan Edit

    In 2020, the Japanese Defense Minister Taro Kono stated that Self-Defense Forces pilots have never encountered a UFO, and that he does not believe in UFOs. He also said he would consider issuing protocols for such encounters. [218] Several months later, the protocols were issued, clarifying what the personnel should do when encountering unidentified flying objects that could potentially pose a threat to national security. [219]

    China Edit

    In 2016, the Chinese Government released a white paper detailing its space program. According to the document, one of the research objectives of the program is the search for extraterrestrial life. [220] It is also one of the objectives of the Chinese Five-hundred-meter Aperture Spherical Telescope (FAST) program. [221]

    EU Edit

    The French space agency has an office for the study of “non-identified aero spatial phenomena”. [222] [223] The agency is maintaining a publicly accessible database of such phenomena, with over 1600 detailed entries. According to the head of the office, the vast majority of entries have a mundane explanation but for 25% of entries, their extraterrestrial origin can neither be confirmed nor denied. [222]

    In 2018, the German Ministry of Economics stated that the German government has no plans or protocol for the case of a first contact with aliens, as the government perceives such event as "extremely unlikely". It also stated that no cases of a first contact are known. [224]

    Israel Edit

    In 2020, chairman of the Israel Space Agency Isaac Ben-Israel stated that the probability of detecting life in outer space is "quite large". But he disagrees with his former colleague Haim Eshed who stated that there are contacts between an advanced alien civilization and some of Earth's governments. [225]

    1. ^ For the purpose of this 1 in 5 statistic, "Sun-like" means G-type star. Data for Sun-like stars wasn't available so this statistic is an extrapolation from data about K-type stars
    2. ^ For the purpose of this 1 in 5 statistic, Earth-sized means 1–2 Earth radii
    3. ^ For the purpose of this 1 in 5 statistic, "habitable zone" means the region with 0.25 to 4 times Earth's stellar flux (corresponding to 0.5–2 AU for the Sun).
    4. ^ About 1/4 of stars are GK Sun-like stars. The number of stars in the galaxy is not accurately known, but assuming 200 billion stars in total, the Milky Way would have about 50 billion Sun-like (GK) stars, of which about 1 in 5 (22%) or 11 billion would be Earth-sized in the habitable zone. Including red dwarfs would increase this to 40 billion.
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    Wikimedia Commons has media related to Extraterrestrial life .
    Wikiquote has quotations related to: Alien life
    Wikisource has original works on the topic: Extraterrestrial life
    • Baird, John C. (1987). The Inner Limits of Outer Space: A Psychologist Critiques Our Efforts to Communicate With Extraterrestrial Beings. Hanover: University Press of New England. ISBN978-0-87451-406-3 .
    • Cohen, Jack Stewart, Ian (2002). Evolving the Alien: The Science of Extraterrestrial Life. Ebury Press. ISBN978-0-09-187927-3 .
    • Crowe, Michael J. (1986). The Extraterrestrial Life Debate, 1750–1900. Cambridge. ISBN978-0-521-26305-4 .
    • Crowe, Michael J. (2008). The extraterrestrial life debate Antiquity to 1915: A Source Book. University of Notre Dame Press. ISBN978-0-268-02368-3 .
    • Dick, Steven J. (1984). Plurality of Worlds: The Extraterrestrial Life Debate from Democratis to Kant. Cambridge.
    • Dick, Steven J. (1996). The Biological Universe: The Twentieth Century Extraterrestrial Life Debate and the Limits of Science. Cambridge. ISBN978-0-521-34326-8 .
    • Dick, Steven J. (2001). Life on Other Worlds: The 20th Century Extraterrestrial Life Debate. Cambridge. ISBN978-0-521-79912-6 .
    • Dick, Steven J. Strick, James E. (2004). The Living Universe: NASA And the Development of Astrobiology . Rutgers. ISBN978-0-8135-3447-3 .
    • Fasan, Ernst (1970). Relations with alien intelligences – the scientific basis of metalaw. Berlin: Berlin Verlag.
    • Goldsmith, Donald (1997). The Hunt for Life on Mars. New York: A Dutton Book. ISBN978-0-525-94336-5 . , "Alone in the Milky Way: Why we are probably the only intelligent life in the galaxy", Scientific American, vol. 319, no. 3 (September 2018), pp. 94–99.
    • Grinspoon, David (2003). Lonely Planets: The Natural Philosophy of Alien Life. HarperCollins. ISBN978-0-06-018540-4 .
    • Lemnick, Michael T. (1998). Other Worlds: The Search for Life in the Universe. New York: A Touchstone Book. Bibcode:1998owsl.book. L.
    • Michaud, Michael (2006). Contact with Alien Civilizations – Our Hopes and Fears about Encountering Extraterrestrials . Berlin: Springer. ISBN978-0-387-28598-6 .
    • Pickover, Cliff (2003). The Science of Aliens. New York: Basic Books. ISBN978-0-465-07315-3 .
    • Roth, Christopher F. (2005). Debbora Battaglia (ed.). Ufology as Anthropology: Race, Extraterrestrials, and the Occult. E.T. Culture: Anthropology in Outerspaces. Durham, NC: Duke University Press.
    • Sagan, Carl Shklovskii, I. S. (1966). Intelligent Life in the Universe. Random House.
    • Sagan, Carl (1973). Communication with Extraterrestrial Intelligence. MIT Press. ISBN978-0-262-19106-7 .
    • Ward, Peter D. (2005). Life as we do not know it-the NASA search for (and synthesis of) alien life. New York: Viking. ISBN978-0-670-03458-1 .
    • Tumminia, Diana G. (2007). Alien Worlds – Social and Religious Dimensions of Extraterrestrial Contact . Syracuse: Syracuse University Press. ISBN978-0-8156-0858-5 .

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    Top 10 Different Types Of Alien Species On Earth

    Sighting of aliens have been reported by hundreds of people over the last one hundred years from different parts of the world. As per collective studies of all these reports, it is being calculated that there are as many as 82 different types of aliens that are being seen on earth! Here is a brief description about the top 10 different types of aliens that have been spotted on earth.

    Type 1 : Zeta Reticulans or Grey Aliens

    The most common type of aliens that are being seen across the globe by people of all ages is the zeta reticulan type, which is also commonly referred to as the ‘Greys’. These extraterrestrial beings are typically 3-4 feet tall and have large almond shaped black eyes. Their head is much larger than a regular human’s head and they have no noses, but only nostrils. Their arms are usually longer that has not more than three to four fingers. It is the Zeta reticulans who are thought to be the main culprits behind most human abductions.

    Type 2 : Little green men

    Another common type of alien is the little green men that have been reported to have been sighted by different people in different places. These types of extraterrestrials are humanoid creatures with a greenish skin color and their bodies are devoid of any hair. Some of the little green men have been reported to have antennas on their heads, which are much larger than a regular human head.

    The Nordics would look just like humans and they would have long blonde hair that would be maintained by both male aliens as well as the female ones. These aliens are not identifiable even if they walk among a crowd. The only way to identify them is when they manifest some of their extraterrestrial activities. These aliens usually have angular faces with blue eyes. The females of the Nordic alien type have a high sex appeal.

    Type 4 : Pleiadian Aliens

    The aliens of the Pleiadian type are characterized by round faces and tall figure and the rest of the features are soft but detailed. The overall appearance of the Pleiadians is a very pleasant one and although they do not have hair usually, but if someone has any hair on the heads, the hair is blonde colored. These aliens are known to be very gentle and peace loving by nature.

    Type 5 : Andromedan Aliens

    You would mistake the Andromedan aliens to be humans, as they look almost like humans, with the only difference being in their overall size. These aliens are bipedal energy beings who can read the minds of humans by means of telepathy.

    Another very common type of aliens is the reptilians who are tall and have scales over their humanoid body structure. These aliens would have webbed feet and would look more or less like a reptile when you see them for the first time.

    Type 7 : Alpha Draconian

    The most corrupt, hostile and vicious type of aliens are the alpha draconian. These aliens are believed to have come from Alpha Draconis and are characterized by giant reptilian features. These aliens are about 14 to 22 feet tall and weigh approximately 1800 pounds or more. They believe themselves to be the rightful owners of the humans who are lesser evolved beings as per their standards.

    Type 8 : Sirians Aliens

    The Sirians are those types of aliens that in spite of having a humanoid structure prefer to live around in the water. These aquatic aliens are mostly found in oceans and lakes where there is huge depth. They are known to have come from Sirius B Star system.

    The ancient Sumerians used to worship the Anunnaki as their god. The Anunnaki is nothing but aliens that had visited the planet of earth around four thousand years ago with the intention of enslaving humans to carry out farm work with them. The Anunnaki aliens look exactly like humans, but they are slightly larger than the aliens, with average height being 8-9 feet. These aliens are believed to have come from Nibiru, the twelfth planet in our solar system, which lies beyond Pluto and is yet to be discovered.

    Type 10 : Arcturian Aliens

    The arcturians are usually four to five feet tall with large heads and blue skin. The rest of their bodies are highly disproportionate. These types of aliens are believed to be the most ancient race of the entire Milky Way Galaxy and they are considered to be very intelligent, experienced and innovative.

    'Extremely unlikely' aliens are visiting Earth

    Multiple U.S. Navy pilots have reported seeing unidentified aerial phenomena in American airspace in recent years, and top intelligence and military officials are scheduled to release a congressional report this month addressing the topic.

    While the reports are often linked in pop culture to a long history of alleged UFO sightings and alien abductions, several astrophysicists said they were skeptical the phenomena have anything to do with extraterrestrial life.

    "The report on the unidentified aerial phenomena is really important because these certainly are things people have seen," Conselice said. "It’s extremely unlikely, I think, that it's aliens visiting Earth, though that is the most exciting theory of course."

    Conselice said he suspects the reports amount to "strange reflections" or "atmospheric phenomenons."

    According to the Times, officials said the intelligence report could not tie most of the more than 120 incidents of such phenomena over the last two decades to the U.S. military or other advanced government technology. CNN reported the findings leave open the possibility these flying objects were created by other countries, like China or Russia.

    Just because these objects are unidentified, it's "an unwarranted leap" to think that aliens are involved, said Adam Frank, a professor of physics and astronomy at the University of Rochester.

    "There's nothing going on in these videos (of UFOs) from a scientist's perspective that's mind-blowing," Frank said.

    Jack Singal, an astrophysicist and associate professor of physics at the University of Richmond, cautioned scientists to maintain "an appropriate level of skepticism."

    "Now, more than ever, videos and photographs can be deceptively edited, and misinformation can spread through social media like wildfire," Singal said. "Also just because something in the sky is strange that does not mean it is necessarily from another planet."

    But that doesn't mean researchers aren't looking.

    The Star People: ‘Extraterrestrials’ From A Native American & First Nations Perspective

    Arjun Walia 12 minute read

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    Scholars have estimated that, prior to the ‘discovery’ of the Americas by Europeans, the pre-contact era population could have been as high as 100 million, you can read more about that here. The people that roamed these lands comprised of extremely intelligent beings full of knowledge and teachings that were, unfortunately forgotten by most, but carried on by a few. It’s these teachings that can play a big part in guiding us back to a human experience where all life can thrive. Yes, it is possible, our potential as a human race is greater than we know.

    Another aspect of this society might have also dealt with extraterrestrial contact. I am not Native American, so when it comes to the topic of sharing beliefs from our very recent past from this culture, it’s best to leave it up to those who are direct descendants from where these stories permeated, and those who grew up around the Elders sharing them.

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    Stories of intelligent beings visiting our planet from the cosmos date back to the beginning of time, and span throughout several different cultures at various points in human history. Antiquity is filled with stories of beings, materials and flying objects that, according to modern day thinking, should not have existed.

    When it comes to Native American ‘lore’ and extraterrestrials, they were commonly referred to as ‘Star Beings.’

    For example, Richard Wagamese, One of Canada’s foremost authors and storytellers from the Wabaseemoong First Nation in Northwestern Ontario writes how:

    “My people tell of Star People who came to us many generations ago. The Star people brought spiritual teachings and stories and maps of the cosmos and they offered these freely. They were kind, loving and set a great example. When they left us, my people say there was a loneliness like no other.” (source)

    He goes on to write, “If Star People did come to the Ojibway, where did they go? Where did they come from? Who brought teachings to them? What scientific magic did they own that allowed them to make such an incredible journey – and is it possible for us?”

    Well, if you’re reading this Richard, based on my research, I believe they left because of the path the human race was on, one of destruction and, if we are able to restore balance and peace as well as create an experience where all living beings can thrive in harmony, I believe they would return, at least the spiritual beings you speak of in your writing. But that’s just my opinion, one that’s based on years of research and intuitive feelings.

    Another example comes from Stephane Wuttunee, who is a Plains Cree and French Canadian author and storyteller. He wrote a piece for UFO digest in 2008, explaining that his perception and understanding “of the ET phenomena as a Native person and its global implications” comes from “having been partially raised within the culture itself.”

    In his article, he makes a clear point to mention that, in his culture, they “give far greater attention to the seeking of the spiritual understanding of things rather than going after “the truth” as people from dominant cultures do. This is part of the reason why we tend to stand back and view or listen at first rather than bare in with questions or take the hard, direct approach.” (source)

    I think it’s important to mention the spiritual understanding and implications are connected to this topic, especially with all of the fear propaganda that is continuously pumped out into the mainstream. Yes, it’s going to ruffle a lot of feathers and interfere with the belief systems of many, but sometimes it’s ok to put those aside to at least entertain another idea.

    Wuttunee, like Wagamese, mentions the “Star People.” Stating that, while growing up, he heard of “distant relations and Star People living amongst the stars many times, mainly around campfires and during traditional ceremonies. Far from being anything to be feared, Star People was just another term I grew up around. I remember listening in awe and fascination at the thought of us having relations that lived off and outside our world, and sometimes spoke to them in my silent moments at night. I wanted to know who they were and what they looked like, if they had families like us etc. In all honesty, the only time I was exposed to “aliens” per se was when I would goto the outhouse and read the Weekly World News or National Enquirer. It wasn’t until my later teens that I discovered that people from the dominant cultures were talking about the same “people” as my elders did, though each side’s sense of perception of these people seemed radically different from one another.”

    He goes on two write about how his elders never really made any clear distinctions between extraterrestrials and the spirit world.

    “In fact, at times I heard Aboriginal elders blend the two together and treat them as one, which I have to admit did kind of take me for a spin when I was young. Were our distant relations physical like us? Did they also exist amongst us in spirit? I had many unanswered questions, so I guess from a fairly young age I had some unraveling to do.”

    He also points out how stories of abductions were not really spoken of, but rather stories of interactions with beings from other worlds and realms, mostly using telepathic communication and, sometimes, full on physical and friendly encounters.

    “To this day, I’ve often wondered for instance, if White Buffalo Calf Woman, the teacher who brought Native people the four traditional medicines of sweetgrass, sage, cedar and tobacco might have been one of these otherworldly visitors.”

    He ends his article by making the an important point (to him), that in his culture, there is no reason to be fearful, and that the Star People come from far away and visited us quite often in the past, and will do so again in the future.

    In light of the way things are in the world, I’d have to say it’s about time someone dropped in again for some tea and bannock, in any case, the fire is lit and the door is open.”

    Blow is a video of Sioux Chief Golden Light Eagle speaking about the Star People. One thing that really resonated with me was the fact that he mentioned modern day terms like “extraterrestrial” and “EBE, and how they create separation and judgements. It reminded me of a video where the Dalai Lama urged us to look upon them as we look upon ourselves — another equal form of life. You can watch that video and read more about that here.

    Modern Day Knowledge & The ‘Spiritual Implications’ of Extraterrestrial Contact

    It’s always interesting to listen to the stories regarding beings from another world or realm, especially when it comes from Native American culture because we already know how much wisdom, knowledge and truth comes from them.

    When it comes to the topic of ET’s, as one of the authors above pointed out in his article, the lore surrounding the subject propelled him to do further research.

    It’s especially interesting to contemplate contact with native cultures because today, as former NASA astronaut and Princeton physics professor Brian O’Leary states, “there is abundant evidence that we are being contacted, that civilizations have been visiting us for a very long time.” The fact that people with backgrounds like O’learys’ now number in the hundreds are coming forward and sharing what they know has people all over the world interested in this subject. (source)

    “There is a serious possibility that we are being visited and have been visited for many years by people from outer space, from other civilizations. That it behooves us, in case some of these people in the future or now should turn hostile, to find out who they are, where they come from, and what they want. This should be the subject of rigorous scientific investigation and not the subject of ‘rubbishing’ by tabloid newspapers.” (source)

    The quote above comes Lord Admiral Hill-Norton, the former Chief of the Defence Staff and 5 star Admiral of the Royal Navy. That’s the highest possible rank of the British Royal Navy, similar to General Dwight Eisenhower’s 5 star rank in the United States. He was also Chairman of the NATO Military Committee.

    Apart from all of these comments and witness testimony that’s surfaced, we have a number of documents that have been released into the public domain that corroborate these stories.

    Given this evidence, the possibility that this is happening is very real and if you’d like to read/learn more about this topic, you can start off by visiting the exopolitics section of our website. There you will find our most recent articles on the subject, dated back to the very first one we ever wrote. It’s just too deep of a subject to show all of the evidence I’ve shown in previous articles, so please do take a look if you’re curious. Another great place to get started if you’re interested is at richarddolanpress.com, some good books available there.

    But what does all of this mean? If we aren’t alone, and we indeed have been and are being visited, what are the implications?

    The spiritual aspect of the Native American lore is very appealing to me, especially because after all of my years of research into this topic, there are stories from both ‘insiders’ and experiencers a like regarding the spiritual nature of some extraterrestrial beings, the well being of this planet and the current path the human race is on.

    That being said, there is also information that can be scary to contemplate as well. But for the most part, these stories are lathered with the idea that may of these beings, whoever they are and wherever they come from, do not claim to be gods, but are aware of the fact that we are indeed ‘spiritual’ beings, and that the ‘spirit’ world many of our previous cultures spoke of is indeed real. The existence of the soul is commonplace within the realm of UFO/ET research and, unfortunately, has made the field subject to labels and other criticisms that come from the mainstream. As mentioned above, the beings that were in contact with Native American ancestors were very spiritual in nature.

    Perhaps this is the main lesson in what is happening today? That humanity has become lost, but may are now awakening, helping humanity to return to it’s roots. We are a species that has forgotten our own history, there is much mystery there, and our connection to all life in this planet is not what it once was. We now destroy our home, and have lost sight of our interconnectedness with everything. Maybe the entire UFO/ET topic is related to this in some sense? Perhaps the closer we return to restoring our Earth, the closer we return to meeting these beings again. Perhaps knowing that we are not alone, can help us remember who we are.

    When it comes to the mainstream perception of extraterrestrials, there is no shortage influence from the mainstream. We are constantly bombarded with the idea of alien invasions, and we might not realize it, but a lot of fear is pumped into us. For the masses to seriously contemplate this topic and start to accept that yes, there really is a high probability we are being visited, and have been visited, is not an easy thing.

    Sure, there might be some malevolent beings out there, just as we see inside the human race, but there must also be the complete opposite. It’s a topic that goes into many different areas of human civilization, and effects what we know about science, technology, the nature of reality and more. Again, I urge you to check out the exopolitics section of our website if you want to go deeper into that type of thing.

    I’ll leave you with this message below. In late September of 2014, Indigenous Elders and Medicine People of North and South America united for four days in sacred ceremony in Green Grass, South Dakota. The significance of this meeting is profound. Its outcome is the Statement which Chief Looking Horse delivers in his native Lakota language, at the United Nations Tillman Chapel. It is the embodiment of a confluence of prophecies which speak to the necessity to activate a new level of consciousness for the benefit of humanity and the earth. Although their statement illuminates the nuclear crisis at Fukushima, the fundamental message is for humanity to spiritually awaken to protect and restore the sacred.

    It’s interesting, because according to various account, this is the message of many ‘contactee’s’ who are currently experiencing contact.

    “We are part of Creation, thus, if we break the laws of Creation we destroy ourselves. We, the Original Caretakers of Mother Earth, have no choice but to follow and uphold the Original Instructions, which sustains the continuity of Life. We recognize our umbilical connection to Mother Earth and understand that she is the source of life, not a resource to be exploited. We speak on behalf of all Creation today, to communicate an urgent message that man has gone too far, placing us in the state of survival. We warned that one day you would not be able to control what you have created. That day is here. Not heeding warnings from both Nature and the People of the Earth keeps us on the path of self destruction. This self destructive path has led to the Fukushima nuclear crisis, Gulf oil spill, tar sands devastation, pipeline failures, impacts of carbon dioxide emissions and the destruction of ground water through hydraulic fracking, just to name a few. In addition, these activities and development continue to cause the deterioration and destruction of sacred places and sacred waters that are vital for Life.” (source)

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