Over the weekend, astronomers made a tantalizing discovery: a mysterious radio beam that emanated from the vicinity of Proxima Centauri, the Sun's closest stellar neighbor, as first reported by The Guardian.
The discovery, made by Breakthrough Listen, a project dedicated to hunt for signals from extraterrestrial life affiliated with the late physicist Stephen Hawking, led to widespread speculation that an alien race may have reached out to us.
A 982 megahertz signal dubbed BLC1 (Breakthrough Listen 1) came from the star, as spotted by the Parkes telescope in Australia in April and May 2019. Most tantalizingly, the relatively nearby star system contains a planet dubbed Proxima b, which is about 20 percent larger than Earth and located in the system's habitable zone, the area where it's theoretically possible for life to sustain itself.
The news also met with a healthy dose of skepticism. In a statement released today, the SETI Institute commented on the controversial report. The main takeaway: Breakthrough Listen's discovery is a candidate, not a confirmed signal.
"Because of its profile, it’s very unlikely that the signal was produced by a natural but unknown cosmic source, but who knows… Nature often surprises us," reads the statement, penned by SETI Institute senior planetary astronomer Franck Marchis.
So you're saying there's a chance? Not exactly.
"One simple explanation is that Parkes picked up a signal that originated on Earth," Marchis writes. "We use radio to communicate, and this could be terrestrial interference. And that’s probably the most likely explanation."
And then there's the simple fact that Proxima Centauri's exoplanet Proxima b has yet to be confirmed, let alone imaged directly.
"We know of its existence only through the motion on its star, so all we have is an estimate of its mass and its orbit, nothing else," the statement reads.
"The idea of a technologically advanced civilization living around our nearest stellar neighbor is quite extraordinary," Marchis admitted.
"But currently, we’re left with more questions than answers: Why was the signal detected only once over 30 hours in April and May?" We also don't know why observers didn't immediately alert the scientific community.
The planetary astronomer also argues that it would be "highly improbable" that two civilizations would end up "using the same technology at the same time."
"It’s probably not alien and we will confirm this soon," Marchis concludes. "Of course, as a SETI Institute scientist, nothing would please me more than to be proven wrong."
READ MORE: Did Proxima Centauri Just Call to Say Hello? Not Really! [SETI Institute]
More on the signal: A Very Strange Radio Signal Is Coming From the Closest Star