Paris (AFP)

Thousands of black holes just a click away: a network of European astronomers calls the general public for help in finding the origin of complex structures detected in the Universe by radio telescope, which are linked to mysterious supermassive black holes present in the center of galaxies.

This new participatory science program, called LOFAR Radio Galaxy Zoo, "gives anyone with a computer the opportunity to help the scientific community" in interpreting the data collected by the LOFAR radio telescope, a set of antennas distributed across Europe , said Tuesday in a press release the Paris Observatory-PSL, which operates the French part of the network.

LOFAR, which observes the radio waves emitted in the Universe, is building a vast image of the "radio sky": unlike images taken with optical telescopes, stars and galaxies are not directly visible there. On the other hand, we see there structures with complex shapes, the origin of which remains mysterious.

"We observe radio waves from charged particles, which are produced by hyper violent physical phenomena, in particular black holes", details AFP Cyril Tasse, astrophysicist at the Observatory, one of the initiators of the project.

When a supermassive black hole is active, the radio telescope only shows the jets of particles it produces - large plumes of gas ejected far out of the galaxy - and not the object as such: as if we were saw the wake of a boat, without seeing the boat.

Now scientists need to locate black holes, to know their "host galaxy". To be able to ultimately reconstruct the scenario of their formation, millions, even billions of years ago, and understand "why there is a black hole at the center of all galaxies", summarizes the astrophysicist.

Hence the idea of ​​launching a participative science site: "LOFAR generates monstrous amounts of data (50 petabytes, the equivalent of a stack of DVDs as high as 40 times the Eiffel Tower)", than the 200 astronomers cannot interpret alone.

"150,000 complex sources need to be identified, and they can only be identified by eye," says Cyril Tasse.

Using a video tutorial, each participant is asked to superimpose a radio image and an optical image, and thus find the host galaxy of the black hole. Or eliminate the scenario of a black hole - radio jets can also come from other processes such as star explosions.

Astronomers expect a million clicks.

© 2020 AFP