We may be the only species in the cosmos. Earth is the sole habitable planet, and humans are the only sentient species. Certainly, this is what scientists tell us, but many feel that there have already been meetings with extraterrestrial species. Area 51 is the Air Force installation in Nevada where extraterrestrials are purportedly frozen by the United States government. In 1947, there was an unexplained occurrence at Roswell, New Mexico, and in Colorado, cows were mangled. (extraterrestrials have visited Earth)

At least since the fifth century B.C., when the Greek philosopher Democritus suggested "innumerable planets of varying proportions" that were not all lifeless, the possibility that there are other intelligent living forms in the cosmos has been considered. The Roman poet Tito Lucrecio Caro described "other realms" with "other tribes of mankind and terrible monsters" four hundred years later. In the seventeenth century, the German scientist Johannes Kepler described a voyage to the moon during which explorers saw reptilian-like animals. (extraterrestrials have visited Earth)

Near the end of the 17th century, the Dutch mathematician Christiaan Huygens penned a book in which he hypothesized about the circumstances of other planets and concluded that at least some of them must have supported life. In 1894, when the American astronomer Percival Lowell pointed his telescope at Mars, he observed what he believed to be a network of channels, sophisticated constructions that could only have been constructed by intelligent creatures.

Yet it wouldn't just be legends and hypotheses from the past, since some academics take this possibility seriously and look for proof of extraterrestrial life outside our globe. Yet the last thing we would anticipate is for a NASA scientist to suggest that it is likely that alien civilizations had already visited Earth. (extraterrestrials have visited Earth)

Very intelligent super-small creatures

Professor and NASA scientist Silvano P. Colombano of the Directorate of Intelligent Systems has revealed in recent study that alien life may have already visited Earth. According to MailOnline, he also promises that it is likely that it is extremely different from the carbon-based species that are now prevalent on our planet.

Colombano noted in a paper, "I only want to point out that the intelligence we may encounter and that could choose to locate us (if it hasn't already) may not be formed by carbon-based species like ourselves."

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Colombano stated that scientists should reevaluate their beliefs, from the life of an extraterrestrial to its height, because a cosmic explorer may be a tiny, superintelligent organism.

The scale of the 'explorer' may be that of a very intelligent, superintelligent being.

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Nevertheless, Colombano goes farther, asserting that extraterrestrials may have developed a technology that humans do not yet comprehend, which makes interstellar travel conceivable.

The NASA scientist proposed, "If we accept a new set of assumptions about what higher kinds of intellect and technology we may discover, some of these events could match with particular theories and we could launch a serious inquiry,"

Even so, the scientist concedes that interstellar travel may be impossible in tens of thousands of years, but he adds that it may be doable depending on our assumptions about different life forms.

"Taking into account that the technological development of our civilization began approximately 10,000 years ago and that scientific methodologies have only emerged in the last 500 years, we can assume that it will be extremely difficult to predict the technological evolution over the next thousand years," he concluded.

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And if anyone believes that Colombano, who holds a doctorate in biophysical sciences, has completed his astonishing research, he is sadly mistaken. In addition, he has urged other experts to research UFO encounters thoroughly. In fact, this is just what ufology specialists have been seeking. The most remarkable aspect, though, is that a NASA scientist makes this breakthrough and calls his colleagues.

Are they prepping us for contact with extraterrestrials?