Greetings, citizens of the Earth!
You’ve probably heard about the story, published in the Guardian, a reputable British newspaper, about the potential discovery of an extraterrestrial signal from the Proxima Centauri system, the closest star to us.
This article and an accompanying piece in Scientific American, mentioned that in April and May 2019, the Parkes telescope in Australia was listening to Proxima Centauri, a red dwarf. This star is known to be active, and this listening was part of a stellar survey.
Shane Smith, a student at Breakthrough Listen, a privately funded program by Yuri Milner to search for and find so-called techno-signatures or signals that indicate the existence of a civilization like ours, verified the data. He found an extremely curious narrowband broadcast, sharpened with a needle at 982,002 megahertz.
The team inspected the data, confirmed its veracity and named it BLC1 for “Breakthrough Listen Candidate 1.”
The name clearly identifies what it is. E o candidate, not a confirmed signal. Everyone at Breakthrough Listen pointed this out, including CEO Pete Worden.
Due to its profile, it is very unlikely that the signal is produced by a natural cosmic source, but unknown, but who knows … Nature often surprises us.
A simple explanation is that Parkes picked up a signal that appeared on Earth. We use radio to communicate, and this could be terrestrial interference. And this is probably the most likely explanation.
But let’s take a closer look at the source. Astronomers have been paying close attention to the Near Centauri for years. It is the closest planetary system to Earth we know about. In 2016, a team of astronomers led by Guillem Anglada – Escudé announced the discovery of Proxima b, a planet 20% larger than Earth that orbits its star every eleven days.
What really matters to astronomers is that this planet is located in the habitable zone of its star, where there may be liquid water on the surface. But it is crucial to remember that we have not yet taken a photograph of this exoplanet. We know about its existence only through the motion of its star, so we only have an estimate of its mass and orbit, nothing else.
In 2019, astronomers discovered another planet buried in the same data and named it Proxima c. This planet is seven times more massive than Earth and could be a super-Earth or a mini-Neptune. We believe that this world is too far from its star to be habitable.
The idea of a technologically advanced civilization living around its nearest star neighbor is quite extraordinary. But now we are left with more questions than answers: why was the signal detected only once in 30 hours in April and May? What are the characteristics of the signal – ie its profile, power and modulation and varied in frequency over 30 hours due to its movement towards us? Why didn’t observers alert the scientific community immediately after its discovery so that other people could confirm the signal?
Of the 300 million exoplanets that could be habitable in our galaxy, which is 200,000 light-years wide, it would be an astonishing coincidence that two civilizations (ours and one on Proxima b or c) use the same technology at the same time. . Although I like the idea, it seems very unlikely – which is why I suspect we will quickly find a more practical explanation for the origin of the signal.
In addition to the science and mystery associated with this signal, we need to discuss the context and the many conspiracies that affect modern society.
When I meet someone who believes in conspiracy theories involving scientists, such as those proposed by anti-vaxxers or those involving aliens, I tell them that I know my colleagues and there will always be one who escapes a secret like this. And that’s exactly what happened with BLC1, where the story began with a leak from a scientist Breakthrough Listen the Guardian. And what started as a leak is spreading fast in the news. I hope that my colleagues and reporters will point out that this signal is a candidate and NOTHING BUT A CANDIDATE. It is far too early to speculate on the consequences of finding a techno-signature on Proxima Centauri, even if it is attractive and fun to talk about.
2020 has been a crazy year on so many levels, even in the field of SETI. After the mysterious appearance of the monoliths and the announcement of the galactic federation, we now have BLC1, a curious and mysterious signal that may – or may not – come from Proxima Centauri. Probably no stranger and we will confirm this soon. Of course, as a scientist at the SETI Institute, I would like nothing more than to prove myself wrong.
Clear sky,
Franck M.