Astronomers using the RATAN-600 radio telescope in the Russian Republic of Karachay-Cherkessia have detected an unusual signal emanating from a star located about 94 light-years from Earth. It’s not clear if the signal is being transmitted by aliens, but the researchers say we should keep a close watch on this intriguing new extraterrestrial candidate.
As reported by Paul Gilster at Centauri Dreams, the anomalous signal was detected by an international team of astronomers back on May 15, 2015. The researchers, led by N. N. Brusilov, describe a “strong signal in the direction of HD164595,” a planetary system located in the constellation Hercules. The finding is set to be discussed at a meeting of the IAA SETI Permanent Committee on September 27, 2016.
It’s still too early to tell if the signal is coming from an extraterrestrial civilization, but the researchers say it’s serious enough that scientists should now permanently monitor this new target. HD164595 is practically the same size and age as our own sun, it shares a similar chemistry, and it’s less than 100 light-years away. What’s more, it hosts at least one known planet, a warm Neptune in a circular orbit. It’s very possible that other planets reside within this system.
Looking at the signal, the researchers say that if it came from a multi-directional, isotropic radio beacon, it would have to be produced by a Kardashev Type II civilization, i.e. an alien civilization that has tapped into nearly 100 percent of its host star’s energy potential. If the signal was targeted directly at our solar system, then it would be of a power available to a Kardashev Type I civilization, i.e. an alien civilization capable of exploiting nearly all of its home planet’s energy potential.
Another possibility, of course, is that the signal is a natural anomaly, such as background noise. French astronomer Jean Schneider is considering the possibility that HD164595 is amplifying a background radio source through a process known as gravitational microlensing.
To move forward, scientists will need to confirm the quality and integrity of this signal and rule out other possibilities. And by focusing their radio dishes onto this planetary system, scientists may detect new signals, and possibly even patterns. Like the intriguing Tabby’s Star, and the rampant speculation that it’s home to an alien megastructure, more data is needed before we jump to conclusions.
Update: Turns out not everyone is impressed with this anomalous signal. Here’s what Daren Lynch from SETI@home has to say about it:
I was one of the many people who received the the email with the subject “Candidate SETI SIGNAL DETECTED by Russians from star HD 164595 by virtue of RATAN-600 radio telescope.” Since the email did come from known SETI researchers, I looked over the presentation. I was unimpressed. In one out of 39 scans that passed over star showed a signal at about 4.5 times the mean noise power with a profile somewhat like the beam profile. Of course SETI@home has seen millions of potential signals with similar characteristics, but it takes more than that to make a good candidate. Multiple detections are a minimum criterion.
Because the receivers used were making broad band measurements, there’s really nothing about this “signal” that would distinguish it from a natural radio transient (stellar flare, active galactic nucleus, microlensing of a background source, etc.) There’s also nothing that could distinguish it from a satellite passing through the telescope field of view. All in all, it’s relatively uninteresting from a SETI standpoint.