Astrophysicists have revised the SETI search model for extraterrestrial intelligence and developed a new one, with which they re-evaluated the available data.
Why have we still not found evidence of life anywhere but on Earth? Three astrophysicists decided to consider this question in terms of analogy with a "needle in a haystack." Their analysis included the creation of a model to estimate the amount of work done in the search for life off Earth by the SETI project, compared with how much more time it takes before scientists can confidently rule out the possibility that it is nowhere else on our planet. Jason Wright, Shubham Kanodia, and Emily Loubar wrote a paper describing their research and published it on the arXiv.org preprint database.
While it may seem to people who are not cosmologists that scientists have done an incredible amount of work looking for signs of life in other worlds, the reality is most likely the opposite. In 2010, renowned cosmologist Jill Tarter compared the work done at the time to looking for fish in a glass of water, facing a still unexplored ocean. In their new work, Wright, Kanodia, and Loubar have created a model that they believe better appreciates the quest for extraterrestrial intelligence conducted to date. It takes into account the number of searches and the amount of space explored, and compares them to calculations of the size and complexity of our Galaxy and the rest of the Universe.
Researchers have focused on more traditional methods of searching - using telescopes and other advanced equipment to study signals received by the Earth from elsewhere in space. Naturally, this excludes the possibility that alien life is already on Earth, and also does not take into account unexplained phenomena like UFOs.
The researchers found that Tarter's analogy is very close to reality, although in their case they would rather pour the sample from a glass into a pool. Scientists also note that another well-known analogy may need to be modified. They suggest that the search for extraterrestrial life may be like searching a proverbial haystack for one of many needles, rather than just one needle. However, the researchers also noted that it would be enough for us to find at least one.
Vladimir Guillen