New statistical model to help search for extraterrestrial life

Are we alone in the universe or is there an intelligent life? A researcher at the Swiss Federal Institute of Technology Lausanne (EPFL) has developed a new approach to solve this problem: a statistical model to reduce the detection of possible extraterrestrial signals.

Scientist Claudio Grimaldi of EPFL, in collaboration with the University of California at Berkeley, has developed a statistical model that uses Bayes' theorem to calculate the probability of detecting a signal in a given radius around the Earth.

He concludes that if no signal is detected within 1,000 light-years, there is always at least a 10% chance that the Earth will be within the range of hundreds of potential signals from others. parts of the galaxy. The problem is that our radio telescopes are not powerful enough to detect them.

Grimaldi estimates that the probability of detecting an extraterrestrial signal becomes very slim at 40,000 light-years from Earth. At this distance, "we can reasonably conclude that no other civilization with the same level of technological development as ours is detectable in the galaxy," said EPFL in a statement.external link.

However, scientists have so far been able to search for signals only at a distance of 40 light-years.

We hope that Grimaldi's method – described in an article published in the Proceedings of the National Academy of Sciences of the United States of America (PNASexternal link) – could make scientific research cheaper and more effective.

The "Wow! Signal"

Researchers have been looking for signs of extraterrestrial life for nearly 60 years. Several research projects related to Extraterrestrial Intelligence Search (SETI) have been launched since the late 1950s, mainly in the United States. These include the monitoring of electromagnetic radiation to detect the signs of transmission with the latest high-performance radio telescopes.

Despite the considerable progress of radio astronomy and the increase in computing power, none of these projects has produced anything concrete. Several signals have been recorded, such as "Wow! signalexternal link"In 1977, but scientists could not determine the origin. And none of them has been repeated or seems credible.

Scientists have not given up, however. SETI has experienced renewed interest following the discovery of nearly 4,000 planets outside our solar system, called exoplanets. Researchers have also developed sophisticated new instruments, such as the Square Kilometer Array, a giant radio telescope built in South Africa and Australia, with a total square footage of one square kilometer, which could pave the way for promising advances.

Russian entrepreneur Yuri Milner recently announced an ambitious program called Breakthrough Listen.external link, which aims to cover 10 times more sky than previous research and to scan a much wider frequency band. Milner intends to fund his initiative with $ 100 million over 10 years.