Over the years, there have been many speculations about extraterrestrial life, with scientists going so far as to propose that laser cloaking could actually hide us from the prying eyes of aliens! Across the globe, a major chunk of scientific research is allocated to the search for extraterrestrial intelligence. In 2014, for instance, NASA published a study about Caribbean shrimps that, it believed, could shed more light on alien life forms.

Similarly, a team from Switzerland’s Federal Institute of Technology (EPFL) have developed an advanced nanoscale motion sensor that could potentially look for ET. According to a new study by Cornell University, however, alien contact will likely not be possible for another 1,500 years. Speaking about the paper, which was presented at a recent meeting of the American Astronomical Society, Evan Solomonides, one of the chief authors, said:

We haven’t heard from aliens yet, as space is a big place – but that doesn’t mean no one is out there. It’s possible to hear any time at all, but it becomes likely we will have heard around 1,500 years from now. Until then, it is possible that we appear to be alone – even if we are not. But if we stop listening or looking, we may miss the signals. So we should keep looking.

Working alongside Yervant Terzain, a professor of astronomy at the university, Solomonides successfully deconstructed the Fermi paradox, which states that our galaxy is filled with billions of planets similar to Earth. For the research, the team also looked at the mediocrity principle postulated in the 16th century by renowned mathematician Copernicus. According to this principle, our planet’s physical attributes are not that unique, so it might be a while before extraterrestrial beings seek us out.

One of the key factors in the hunt for alien life is the rate at which our broadcast signals are travelling through the galaxy. Believe it or not, we have been indirectly making our presence known to the other worlds for over 80 years now, thanks to TV and radio signals that are constantly beamed into space. This in turn means that such signals have managed to reach all celestial bodies  located within 80 light-years from Earth. As the scientists point out, that runs to about 8,531 stars and nearly 3,555 planets.

Disappointing though it is, so far we haven’t received any kind of response. While it may seems like a lot of planets and stars, it only the tip of the iceberg. Milky Way is believed to be home to more than 200 billion stars and several hundred billion Earth-like planets. Hence, the mediocrity principle. Talking about this rather grim idea, Carl Sagan once said:

We find that we live on an insignificant planet, of a humdrum star, lost in a galaxy, tucked away in some forgotten corner of a universe in which there are far more galaxies than people.

With the help of the Fermi paradox and the mediocrity principle, the researchers were able to estimate the minimum number of years before we can expect a reply from the mysterious beings out there. According to the team, it is quite possible that alien contact will take place within the next 1,500 years, which is how long it will take for our radio signals to spread over half of our galaxy.  Solomonides added:

This is not to say that we must be reached by then or else we are, in fact, alone. We simply claim that it is somewhat unlikely that we will not hear anything before that time.

Source: Cornell University