It might sound like something that's purely science fiction, but it's a legitimate and busy area of scientific research. Astronomers are attempting to find signs that intelligent life might exist out in the universe beyond Earth. The search for extraterrestrial intelligence, or SETI, is a field that has one huge primary challenge, and that's the sheer size of space. Even if there are other civilizations out there, the gulf between galaxies is so large that signals would take millions of years to travel between them.
So to have any hope of finding indications of
intelligent life, scientists need to look through an enormous amount of data. Searching as much of the sky as possible, investigating as many cosmic objects as possible, in the hope of finding one that could indicate intelligent life elsewhere.
The typical approach to SETI is to look for what are called technosignatures, which are indications of the use of technology. That includes things like radio waves, which would look different when produced by technological sources as opposed to natural ones. It could involve looking for particular chemicals which are typically pollutants caused by technology such as chlorofluorocarbons (CFCs). And somewhat more outlandish is to look for evidence of advanced technology that humans haven't built yet but have conceived of, such as Dyson spheres which are imagined structures around stars used to harvest energy.
Even with this approach in hand, though, SETI researchers are still facing the numbers problem. They need to comb through huge quantities of data to look for these indicators.
To help with the search for technosignatures, researchers are now making use of the Karl G. Jansky
Very Large Array (VLA), a set of 28 massive radio dishes located in New Mexico. These multiple dishes, or antennae, work together to form the equivalent of a single, enormous antenna, allowing them to detect faint signals from distant objects. Each dish is 82 feet across, holds eight receivers, and is mounted on a tripod-style mount which allows it to move and tilt to point at desired objects.
The VLA has a cutting-edge detector called the Commensal Open-Source Multimode Interferometer Cluster (COSMIC) from the SETI Institute, which is specifically designed for SETI research. Described in a
paper in The Astronomical Journal, this is a digital tool that can search for technosignatures in a much more comprehensive and efficient way than previous tools, allowing researchers to process large amounts of data more quickly. It is also designed to enable the VLA to be used for other science research while performing its SETI work.
"The COSMIC system greatly enhances the VLA's scientific capabilities. Its main goal of detecting extraterrestrial technosignatures addresses one of the most profound scientific questions ever. This topic was previously not possible with the VLA,"
said Dr. Paul Demorest of the National Radio Astronomy Observatory. "By operating in parallel with projects such as the VLA Sky Survey, COSMIC will accomplish one of the largest SETI surveys ever while still allowing the VLA to carry out its usual program of other astronomical research.".............
https://www.slashgear.com/1498262/how-scientists-survey-sources-for-intelligent-life/