The Search for Extraterrestrial Intelligence Institute (SETI) quietly issued a statement Monday, Aug. 29, saying a signal had been detected coming from a solar system 95 light years from Earth. In astronomic terms, the news sounded as if our alien neighbor down the street had come a’knocking.
But the statement by SETI’s senior astronomer, Seth Shostack, was quick to minimize the discovery of the signal coming from HD164595, as the system is known, even as it was being announced.
“The chance that this is truly a signal from extraterrestrials is not terribly promising, and the discoverers themselves apparently doubt that they’ve found ET. Nonetheless, one should check out all reasonable possibilities, given the importance of the subject,” Shostack wrote.
Dr. Alex Filippenko, professor of astronomy at UC Berkeley elaborated, “The signal detected by RATAN-600 has a nearly zero chance of being a transmission from an intelligent extraterrestrial. It’s a broad-band detection that has numerous more-plausible explanations including noise, a terrestrial origin, and a celestial origin unrelated to aliens.”
Still, the mere possibility the signal was sent by aliens is fascinating, if only to imagine civilizations far more advanced than our own.
Shostack said, if this message was actually from aliens, they are broadcasting it at 100 billion watts. “That’s hundreds of times more energy than all the sunlight falling on Earth, and would obviously require power sources far beyond any we have,” he wrote.
The beam itself seems to be aimed right at planet Earth. While humanoids might think they are worth the trouble to contact, that would mean the signal began its focused journey across the cold, dark reaches of space long before humans were emitting any radio or television signals from Earth.”
“The energy such a targeted signal would require… even if they are using an antenna the size of the 1000-foot Arecibo instrument…would still need to wield more than a trillion watts, which is comparable to the total energy consumption of all humankind,” Shostack wrote.
The signal was originally picked up by the RATAN-600 telescope at the Southwestern tip of Russia near the Black Sea. On Sunday, Aug. 28, the Allen Telescope Array (ATA) slowly cranked its sea of listening dishes at the Hat Creek Radio Observatory in Lassen National Forest to face the slice of sky where HD164595 can be found.
Shostack noted that the original signals were first detected in May 2015. “The discoverers didn’t alert the SETI community to this find until now, which is not as expected. According to both practice and protocol, if a signal seems to be of deliberate and extraterrestrial origin, one of the first things to do is to get others to attempt confirming observations,” Shostack wrote.
Update: On Wednesday, Aug. 31, the ATA had not found any signal from the region of space where it was first detected . Later, the Russian news agency, TASS, issued a statement saying Russian astronomers had located the source. The signal was coming from a Soviet-era military satellite.
SETI reminded the public that an array of telescopes is always better than one.