A NASA scientist has claimed that Earth may have been once visited—or is being visited—by extraterrestrials, but we may not have realized it.
Silvano P. Colombano, who works at NASA Ames Research Center and is also a professor, theorizes that intelligent life may not be carbon-based or what we’re used to.
If those alien lifeforms are not carbon-based, it would change our assumptions about what to look for.
He said, “How might that change the above assumptions about interstellar travel? Our typical life spans would no longer be a limitation (although even these could be dealt with multigenerational missions or suspended animation), and the size of the ‘explorer’ might be that of an extremely tiny super-intelligent entity.”
Colombano then asked, “And how might this change our assumptions about openness or desire to communicate with other civilizations?”
In the paper, he also suggested that extraterrestrials might have figured out technology that human beings cannot comprehend. “If we adopt a new set of assumptions about what forms of higher intelligence and technology we might find, some of those phenomena might fit specific hypotheses, and we could start some serious enquiry,” he explained.
It also means that scientists could miss signals of a civilization inhabiting another planet.
“Considering further that technological development in our civilization started only about [10,000] years ago and has seen the rise of scientific methodologies only in the past 500 years, we can surmise that we might have a real problem in predicting technological evolution even for the next thousand years, let alone 6 million times that amount!” he wrote.
In the paper, Colombano added that “if the speed of light continues to be an unbreakable barrier, over spans of thousands of years civilizations could probably make interstellar journeys, depending on what assumptions we make about the forms of life.”
Referring to the ongoing efforts to search for intelligent life, Colombano wrote that there has been a “very high likelihood of hoaxes, mistaken perceptions, or even psychotic events in UFO phenomena.”
“The general avoidance of the subject by the scientific community. I think the approach the scientific community could take, instead, is very similar to what SETI has done so far: find the signal in the noise,” he concluded.
“In the very large amount of ‘noise’ in UFO reporting there may be ‘signals’ however small, that indicate some phenomena that cannot be explained or denied. If we adopt a new set of assumptions about what forms of higher intelligence and technology we might find, some of those phenomena might fit specific hypotheses, and we could start some serious enquiry.”
Other details are not clear.