This week the Chinese "Sky Eye" telescope picked up a curious signal that could come from extraterrestrial technology. At least that's what the Chinese newspaper reported Science and Technology Daily, before removing the article.
Ok. Well done. The head of the new China Extraterrestrial Civilization Research Group research project, prof. Zhang Tongjie, he had said it in January 2021: “we will be the first to find proof of the existence of extraterrestrials,” and he did.
Or not?
We should be intrigued, but not too much. To determine whether a signal truly comes from space or is simply the result of an unexpected source of terrestrial interference, it must go through several checks.
But let's take a small step back first.
Sky Eye
Officially known as FAST, (an acronym for Five-hundred-meter Aperture Spherical Telescope) with its 500 meters of width it is the largest and most sensitive single-disc radio telescope in the world. An engineering marvel, whose gigantic structure is built in a natural basin in the mountains of Guizhou, China .
FAST is so large that it cannot be physically tilted, but can be directed in one direction through thousands of deformation actuators that bend its reflective surface. At that point the position of its focal point changes, and the telescope can observe a different section of the sky.
FAST detects radiation at radio wavelengths (up to 10 cm) and is used for astronomical research in a wide range of areas. One of these is the search for extraterrestrial intelligence, or SETI.
Hunt for alien technology
In the 60s, American astronomer Frank Drake aimed the Tatel telescope (it's endearing to say today, it was 26 meters wide) towards two nearby stars looking for signs of technology. Since then, research began on the 'technological signatures' of aliens: the 'collateral' signals that would demonstrate the presence of advanced civilizations on other planets (and therefore technologies, or even pollution).
Regardless of what those who are carefully following the interesting series of meetings between the US Congress and the Pentagon (with UAP sightings attached) think, in these 60 years we have yet to find any final proof of life beyond earth.
And yes, FAST is not a telescope for children. It follows 38 billion tracks per second, which it processes by a group of super computers capable of producing detailed graphs of the analyzed signals. The traces thus obtained are then analyzed to look for "technosignatures" which would show the presence of extraterrestrial civilizations.
Its sensitivity allows it in theory to pick up even a single radar signal from a nearby exoplanet. Doesn't he miss anything?
The problem is another. Indeed, the telescope itself.
The extraordinary sensitivity of FAST today also represents its limit. Picking up even very small signals increases the risk of being misled by man-made interference.
It has already happened on other telescopes: last year, for example, researchers at the Murriyang telescope detected a very special signal, which they called BLC1. Even on that occasion more than one expert jumped from their chair and perhaps got caught up in the enthusiasm. And even on that occasion it turned out to be a strange interference, but definitely NOT alien.
It took a year, however, to figure it out. And scientists had to develop a new verification system. You see it here.
It takes time and more
As with BLC1, with FAST it may also be necessary to wait a while before the captured signal is analyzed in depth.
To recognize it is the same professor zhang tongjie in the report he presented:
“The possibility that the suspicious signal is some sort of radio interference is also very high and needs to be further confirmed and ruled out. This could be a long process. "
And we may have to get used to a gap between looking for candidate signals and verifying them. FAST and other telescopes are likely to find many more signals of interest.
Most of these will turn out to be interference, but some may be new astrophysical phenomena and some may be technological signatures in good faith. Maybe. In any case: calm down.
