Le signal est récolté par le radio-télescope Parks et toute la question (voir détails
infra) est de déterminer s'il ne s'agit pas d'interférence humaine (radio ou satellite).
Astronomers behind the most extensive search yet for alien life are investigating an intriguing radio wave emission that appears to have come from the direction of Proxima Centauri, the nearest star to the sun.
The narrow beam of radio waves was picked up during 30 hours of observations by the Parkes telescope in Australia in April and May last year, the Guardian understands. Analysis of the beam has been under way for some time and scientists have yet to identify a terrestrial culprit such as ground-based equipment or a passing satellite.
Plus loin, le signal appelé BLC1 est le thème d'une préparation d'un article scientifique:
The latest “signal” is likely to have a mundane explanation too, but the direction of the narrow beam, around 980MHz, and an apparent shift in its frequency said to be consistent with the movement of a planet have added to the tantalising nature of the finding. Scientists are now preparing a paper on the beam, named BLC1, for Breakthrough Listen, the project to search for evidence of life in space, the Guardian understands.
Attendons donc cette publication / ce rapport.
L'avis du professeur d'astronomie Jason Wright, professeur d'astronomie à PennState, membre du Breakthrough Listen sur son blogue répond à certaines de mes remarques:
https://sites.psu.edu/astrowright/2020/ ... d-proxima/
Ce passage est intéressant: Wright décrit les caractéristiques du signal, qui correspondrait à un truc étrange, mais Wright se plaint aussi de la manière dont cela a fuité dans les media ("Guardian", "National Geographic", "Scientific American") empêchant l'équipe de faire son travail de publication future.
The Breakthrough Listen project uses the Parkes radio telescope in Australia as one of its tools to search for technosignatures. In this case, they were “piggybacking” on observations of Proxima, the nearest star to Earth, which were looking for radio emissions from stellar flares. These were long stares for many hours per day, for many days. The signals they were looking for are broadband, with complex frequency and temporal structure—basically, if you tuned into it with a radio receiver like the ones we use for FM or AM transmission, it would be present at every frequency, and sound like very complicated static.
But the equipment on the telescope can also be used for SETI, and so the BL team was using the telescope “commensally” to do a SETI experiment simultaneously to the flare study.
And in these data, a signal has apparently survived all of their tests!
Now, this does not mean it’s aliens, as the team has pointed out. It means they have, for the first time, a signal that can’t be easily ruled out as RFI. It’s probably RFI of some pernicious nature, but we don’t know what. Pete Worden of the Breakthrough Listen team says it is “99.9% likely” to be RFI.
We know the signal was present for around three hours, present in 5, 30-minute “on” pointings and not at all in the interspersed “off” pointings. We also know it has a positive drift rate, it appears at 982.002 MHz, and that it appears to be unmodulated.
Other than that, we don’t know much! But there are some things we can conclude based on this little bit of information.
Why isn’t the team releasing more information?
I cannot speak for the team but I know they’re committed to transparency and scientific rigor. They also think hard about how to convey results to the media, and are careful about things like press releases and peer review of results.
Unfortunately, this news leaked out before the team had finished their analysis, so we’re left to read tea leaves and parse vague newspaper statements instead of reading their paper on the topic (which does not exist because they’re not done with their analysis!)
Someone in the “astronomical community” (we don’t know if they are even a member of the team) leaked the story to the Guardian. Their hand having been forced, the team then gave interviews to Scientific American and NatGeo with some more details, emphasizing that the signal is probably RFI.
Now I’m pretty grumpy about this. SETI has extensive post-detection protocols that were not followed by the leaker, exactly to avoid this sort of situation. Especially since the team was definitely going to announce this, there’s no need for the leak.
But really what I’m grumpy about is that the team did not get to announce this on their own terms in a way that made clear what was going on. Instead we have lots of speculation and questions that not even the team can answer (because they haven’t finished their analysis yet!)
A la limite, cette parution sabote le travail de l'équipe sur BLC1. Wright continue en citant le directeur exécutif de Breakthrough Initiatives, Pete Worden dans l'article de "Scientific American":
https://www.scientificamerican.com/arti ... -centauri/
One might think, then, that the case would be closed. But while a natural cosmic source may seem unlikely, it cannot yet be ruled out—and, the thinking goes, as unlikely as a natural explanation might be, an “unnatural” explanation such as aliens is even less likely still. Consequently, every member of the Breakthrough Listen team interviewed for this article steadfastly insists the chance of this being anything other than terrestrial interference is exceedingly remote. “The most likely thing is that it’s some human cause,” says Pete Worden, executive director of the Breakthrough Initiatives. “And when I say most likely, it’s like 99.9 [percent].”
Wright n'est pas d'accord pour conclure que le signal est d'origine humaine puisqu'il y a encore des protocoles d'analyse à effectuer et qu'il est trop tôt pour le dire. Et comme il le dit en conclusion, il faudrait que le signal se répète derechef (oui chef !), sinon ce serait encore un signal "Wow" sur lequel on spécule encore.
Le lecteur curieux lira donc cet avis éclairé de Wright, contre le scepticisme de ses collègues et la science en train de se faire.