Where is everyone?
This question was asked in 1950 by the Italian physicist and builder of the first nuclear reactor, Enrico Fermi.
The question became a paradox that was named in his honor, the Fermi Paradox, which deals with the contradiction between the high probability of the existence of extraterrestrial civilizations due to the enormous number of planets in the Universe and the lack of contact with such civilizations.
Recently published in The Astronomical Journal, the research attempts to answer this question, or suggest a plausible answer.
According to Jonathan Carrol-Nellenback, a computational scientist at the Center for Integrated Research at the University of Rochester, in the United States, intelligent extraterrestrial life could be taking the time necessary to explore the galaxy and completely dominate the movement of stellar systems.
“If you don’t consider the motion of stars when trying to solve this problem, you’re basically left with one of two solutions: Nobody leaves their planet, or we are in fact the only technological civilization in the galaxy,” says Carrol-Nellenback.
The researchers’ theory is based on the fact that stars and planets orbit the center of the galaxy at different speeds and directions, but occasionally come closer together. It would be at this moment that interplanetary travel would occur, when aliens travel to destinations that are closer to them.
Taking this into account, it is believed that extraterrestrials may not have reached us yet or, if they did, they could have visited Earth in the past much earlier than human beings, since Earth is around 4.6 billion years old and Modern humans have inhabited our planet for 200,000 years, with historical records dating back just over 5,000 years.
The research authors suggest that if a visit had occurred in a distant past, it is plausible that its traces would have already disappeared.
They also consider that if contact with our planet had already occurred, another arrival might not be necessary, as extraterrestrial civilizations could prefer to visit uninhabited planets or those still unknown to them.