Astronomers behind the most comprehensive search to date for extraterrestrial life are investigating an intriguing radio wave emission that appears to be coming from the direction of Proxima Centauri, the star closest to the sun.
The narrow beam of radio waves was captured last April and May during 30 hours of observations by the Parkes telescope in Australia, the Guardian understands. Beam analysis has been going on for some time now, and scientists have yet to identify a terrestrial culprit, such as ground equipment or a passing satellite.
It’s common for astronomers in the $ 100 million Breakthrough Listen project to see strange radio waves with the Parkes telescope or the Green Bank Observatory in West Virginia, but so far they have all been attributed to human-induced interference or natural sources.
The latest ‘signal’ probably also has an everyday explanation, but the direction of the narrow beam, around 980 MHz, and an apparent shift in frequency that are said to be consistent with a planet’s motion have contributed to the tantalizing nature of the find. Scientists are now preparing a paper on the beam, called BLC1, for Breakthrough Listen, the project to search for evidence of life in space, the Guardian understands.
The ray that appears to have come from the direction of Proxima Centauri, a red dwarf star 4.2 light-years from Earth, has not been seen since the first observation, according to a person in the astronomy community who requested anonymity as work on the is underway. “It’s the first serious candidate since the ‘Wow! signal, ‘they said.
The “Wow! Signal” was a short-lived narrowband radio signal picked up during a search for alien intelligence, or Seti, by the Big Ear Radio Observatory in Ohio in 1977. The unusual signal, which got its name after astronomer Jerry Ehman “Wow!” in addition to the data, unleashed a wave of excitement, though Ehman warned against drawing “big conclusions from half-height data”.
Launched in 2015 by Yuri Milner, a Silicon Valley science and technology investor, the Breakthrough Listen project listens to the million stars closest to Earth in hopes of detecting stray or deliberate alien broadcasts. The 10-year effort was announced at the Royal Society in London when the late Stephen Hawking called the work “critically important.” Hawking, who saw the future of humanity in the stars, said during the event, “Humanity has a deep need to explore, learn, know. We also happen to be social creatures. It is important for us to know if we are alone in the dark. “
The challenge for astronomers on Breakthrough Listen, and others dedicated to finding intelligent life in the sky, is to discover potential “ engineering signatures ” between the relentless chatter of radio waves from Earth’s equipment, natural cosmic phenomena, and hardware circulating around the planet is spinning. It is not an easy task. In 1997, American alien hunter Jill Tarter, who inspired Ellie Arroway’s character in the movie Contact, discovered a potential signal, but it was later revealed that it was broadcast from an antenna on the Soho spacecraft, a joint mission to observe the sun by NASA. and the European Space Agency.
Although Proxima Centauri is too faint to be seen with the naked eye, it has been intensively studied by astronomers. At least two planets are known to orbit the star. One is a gas giant and the other is believed to be a rocky world about 17% more massive than Earth. Known as Proxima b, the planet orbits its star every 11 days and is located in the so-called “habitable zone,” where the temperature is right for water to flow and collect.
But that does not mean that there is water on Proxima b. Despite its seemingly cozy location, the planet may be hostile to life. In 2017, NASA scientists used computer models to demonstrate that if Proxima b had a terrestrial atmosphere, it could be easily removed by the intense radiation and solar flares unleashed by its parent star. Under this storm surge, the 4-billion-year-old planet could have lost its entire atmosphere in 100 million years.
Pete Worden, the former director of Nasa’s Ames Research Center in California and executive director of the Breakthrough Initiatives, said it was important to wait and see what the project’s scientists concluded: “The Breakthrough Listen team has noticed several unusual signs and is researching this carefully. These signals are likely interference that we cannot fully explain yet. Further analysis is currently underway. “
Others are cautious, to say the least. “The likelihood that this is an artificial signal from Proxima Centauri seems overwhelming,” said Lewis Dartnell, an astrobiologist and professor of science communications at the University of Westminster. “We’ve been looking for alien life for so long and the idea that it could turn out to be on our doorstep, in the next galaxy, piles improbabilities upon improbabilities.
If there were intelligent life there, it would almost certainly have spread much wider across the galaxy. The likelihood that the only two civilizations in the entire galaxy are side by side, among 400 billion stars, absolutely pushes the boundaries of rationality. “
It’s not just the statistics that look bad. Proxima b is so close to its parent star that it is locked to Earth like the Moon. One side is eternal day, the other side in eternal darkness. “It’s hard to imagine how you can have a stable climate system and all the things you need to get from bacteria, which are hardy, to intelligent animal life, which certainly aren’t,” added Dartnell. “But I would like to be wrong.”
Is someone there?
1899 The search for life elsewhere has been long and extremely unproductive, at least as far as the search for alien civilizations is concerned. In the late 1800s, Serbian-American inventor Nikola Tesla believed he had intercepted radio messages from Mars. As far as scientists know from countless observations and decades of robotic probe visits, there is no life on Mars.
1967 Astrophysicist Dame Jocelyn Bell Burnell was working on a mountain of data from a new radio telescope she had helped build when she saw an unusual signal. It was feeble but repeated steadily. After ruling out interference from terrestrial sources, the team considered little green men. The real source turned out to be a pulsar, a spinning neutron star that emits radio waves like a celestial lighthouse.
1977 It happened to be the year Star Wars was released when Jerry Ehman, an astronomer at Ohio State University’s Big Ear radio telescope, discovered something curious while scanning the skies for alien broadcasts. The telescope observed a group of stars called Chi Sagittarii when it recorded a 72-second pulse of radio waves. Ehman circled the data and wrote “Wow!” on the readout and gives the signal its name. Scientists have suggested possible sources, but the signal remains unexplained.
2003 The Seti @ home project, conducted by the University of California at Berkeley with observations from the Green Bank radio telescope and the recently collapsed Arecibo telescope, also discovered an intriguing signal. The 1420 MHz burst of radio waves, known as SHGb02 + 14a, was observed three times before disappearing. The signal resides in the “waterhole” quiet zone of the electromagnetic spectrum, which scientists consider an attractive band for alien civilizations to transmit interstellar signals.