Et would have been very nice, a very welcome cosmic coincidence, so to speak, had it actually turned out that we have technologically talented neighbors. You would finally have been able to exchange ideas, perhaps even visit each other in the long term: from us at least with a laser-driven mini probe, and who knows – depending on how quickly our neighbors would have been on the move – maybe we could have acted as hosts in good time.
Well, we had almost a year to get involved in these prospects. Now they have been taken back. The allegedly artificial radio signal BLC1 reported in December 2020, which was recorded by the Australian Parkes Observatory from the direction of our neighboring star Proxima Centauri, is probably not generated by aliens. Rather, it is a “complex intermodulation product” of multiple signals generated by humans. The background to the disappointment is currently in two The article read in Nature Astronomy.
BLC1 was found by the “Breakthrough Listen” program. It has been searching for intelligent life news across a wide range of the radio spectrum since 2016. In order for a narrowband signal to be counted as an “event”, it must first change its frequency slightly over time – this behavior is expected when the signal is sent from a moving planet or spaceship. Second, it must disappear when the telescope is swiveled away from the source. If it can then also not be assigned to any known human transmitters, it becomes an “interesting signal”. That was the case with BLC1. The signal was then analyzed in detail and thoroughly. With success, if you will.
In any case, the scientists see it positively: Firstly, it has not been shown that there is no life on the exoplanet Proxima b. Second, the search method has proven to be well-engineered. It’s a shame anyway. After all, Proxima Centauri is an interesting system. The star, 4.2 light-years away from us, is a very restless red dwarf. Massive outbreaks of radiation regularly occur, which, at least on the side of the planet Proxima b that is permanently facing the star, probably do not leave much of anything viable. But that also means: If the aliens still had the peace of mind under such catastrophic conditions to pass the time broadcasting radio signals from the back of the planet, they would at least be pretty cool.