Astronomers Murchison Widefield Alley Researchers in Western Australia conducted a search for extraterrestrial signals emanating from around 2,800 galaxies pointing towards the Vela supernova remnant with a spectral resolution of 10 kHz.
This diagram shows what a Kardashev Type III civilization might operate like. Containing stellar energy in so-called Dyson spheres is one way to harness the enormous energy on a galactic scale. The resulting waste heat products should be detectable with telescopes. Image by Danielle Futselaar / ASTRON.
“When we think about the search for extraterrestrial intelligence, we often consider the age and advancement of technology that could produce signals that we could detect with telescopes,” said Dr Chenoa Tremblay from the SETI Institute and Professor Steven Tingay from Curtin University.
“In popular culture, advanced civilizations are depicted as having interstellar spacecraft and the means to communicate.”
“In the 1960s, astrophysicist Nikolai Kardashev proposed a scale for quantifying the degree of technological advancement of extraterrestrial intelligence.”
“The Kardashev scale has three levels. A Type I civilization uses all the energy available on its planet (1016 W); Type II civilizations can consume stellar energy directly (1026 W) and a Type III civilization could consume all the energy emitted by the galaxy (1036 “W)”
“Civilizations at the higher end of the Kardashev scale could generate vast amounts of electromagnetic radiation detectable at galactic distances.”
“Some of the ideas that have been explored in the past have been to harness the light of stars in our galaxy, to colonize the solar system, and to use pulsars as a communications network.”
“Radio waves' ability to penetrate space over long distances and even planetary atmospheres makes them a practical tool for searching for interstellar communications.”
The authors used the Murchison Widefield Array (MWA), focusing on low radio frequencies (100 MHz), to look for signs of alien technology in galaxies beyond the Milky Way.
They observed about 2,800 galaxies in one observation, and determined the distances to 1,300 of them.
“This research represents a major step forward in efforts to detect signals from advanced extraterrestrial civilizations,” Dr Tremblay said.
“The MWA's wide field of view and low-frequency range make it an ideal tool for this type of study, and the limits we set will guide future research.”
of work Appeared in Astrophysical Journal.
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CD Tremblay & SJ Tingay. 2024. An extragalactic wide-field search for technosignatures with the Murchison Wide Field Array. ApJ 972, 76;doi:10.3847/1538-4357/ad6b11
Source: www.sci.news
