In a groundbreaking search for extraterrestrial signals, astronomers have scanned over 1,300 galaxies, but found no evidence of alien communications. The search, conducted with the Murchison Widefield Array (MWA) in Australia, focused on low radio frequencies, a relatively unexplored area for SETI (Search for Extraterrestrial Intelligence). This ambitious project, led by Chenoa Tremblay of the SETI Institute and Steven Tingay of Curtin University, targeted a specific region in the constellation Vela, encompassing 2,880 galaxies, of which 1,317 had their distances accurately measured. By knowing the galaxies’ distances, the researchers could determine the power of any potential transmitters. While the search was unsuccessful in detecting alien signals, it provided valuable constraints on the power required for a civilization to send detectable signals. Their findings suggest that any civilization capable of sending signals strong enough to reach Earth would need to harness the power of a star or multiple stars, equivalent to a Type 2 civilization on the Kardashev scale.
This latest study builds upon previous efforts to search for alien signals, including the Glimpsing Heat from Alien Technologies (G-HAT) project which scanned 100,000 galaxies for hypothetical Dyson swarms. However, no evidence of such megastructures was found. Further research has also focused on constraining the maximum power of potential alien transmitters based on theoretical limits and background noise. Although this search yielded no detections, it provides valuable insights into the challenges and possibilities of searching for extraterrestrial intelligence.
The researchers acknowledge that their observations are not comprehensive enough to rule out the existence of advanced civilizations. They emphasize the need for continued exploration across a wider range of frequencies, as well as the exploration of alternative technologies and communication methods. The study, published in The Astrophysical Journal, highlights the ongoing effort to unravel the mysteries of the universe and answer the age-old question of whether we are alone in the cosmos. The vastness of the search space and the ever-evolving nature of SETI research ensure that the quest for extraterrestrial intelligence will continue, with each new observation pushing the boundaries of our understanding.
