We could say that following the huge jets of plasma emitted by some black holes plasma jets emitted by some black holes, we have begun to find an answer to one of the mysteries of astronomy. of the mysteries of astronomy: what influence do black holes have on the evolution of galaxies? influence on the evolution of galaxies?

The answer, it seems, is that there is a direct link between the two: black holes and galaxies would be linked to each other. black holes and galaxies would be linked. The evidence would be the plasma jets that emitted by these black holes and which, this article shows, have a direction perpendicular to the galaxies. perpendicular to the galaxies they inhabit. What is surprising is the difference in size, from the millions of light years of a galaxy, to just a few light years of a black hole. of a black hole. The study has been reported by Nature Astronomy, and is signed by David Fernández Gil, pre-doctoral researcher at CEFCA.

To understand the proposal, it is important to remember that almost all galaxies have a supermassive black hole at its centre. Our galaxy, for example, contains the so-called Sagittarius A at the centre (famous for having been photographed for the first time two years ago, with the two years ago, using the VLBI technique). With this technique, known as Very Long Baseline Interferometry (VLBI), these holes have now been studied. holes have now been studied. It involves doing a kind of ‘magnetic resonance imaging’ of the universe.

Specifically, they have looked at the jets of plasma emitted by some of these supermassive black holes, and they have supermassive black holes, stretching out over a million and a half light-years. They are a kind of giant lightning bolts that dwarf the galaxy itself and, at the same time, are invisible to the human eye, invisible to the human eye.

Supermassive black holes that are active begin to attract dust and gas around them thanks to their powerful gravitational field. These materials form what is called an accretion disc. The inability to fall to the centre, the pressure from the outer elements and the spinning in this disc generate powerful jets of particles that will spread out immensely. of particles that will spread out immensely, millions of light years.

A relationship between black holes and galaxies

The key to this research is that it establishes a direct relationship between the area the black hole from which these jets of particles emerge and the entire galaxy. galaxy. The minor axis of the galaxy and the orientation of these jets are the same. What is the difference in size, the galaxy is millions of light years across, and the black hole is between one and ten light years across. between one and ten light-years. It's a bit like a grain of sand having a direct influence on the Earth. direct influence on the Earth. In principle, it could be assumed that there is a relationship between the jets and the environment of the black hole, but not with the entire galaxy. And that is what they reveal in this paper.

The result has been obtained by an international collaboration headed by David Fernández from CEFCA, with the participation of Professor Jacobo Asorey, from the Centre for Astroparticle and High Energy Physics (CAPA) at the University of Zaragoza. Zaragoza. They have collaborated with researchers from Sejong University, Yonsei University and Yonsei University. Yonsei University and the Institute of Astrophysics and Space Sciences (all from South Korea), in addition to South Korea), as well as staff from the Max Planck Institute for Extraterrestrial Physics (Germany), the Max Planck Institute for Extraterrestrial Physics (Germany), the California Institute of Technology (United States) and the Paris Observatory.

The principal investigator, David Fernández, is now focusing his PhD on an even broader investigation of black holes. research on active supermassive black holes. He analyses data from the J-PLUS photometric catalogue and information from narrow-band filters. narrow-band filters. He is first characterising the galaxies inhabited by these types of black holes. black holes. The aim is to collect data such as whether it is young or old, its colour, the star formation rate or its of star formation or its history (the stars that formed). These data are combined with the low-frequency radio wavelength catalogues where we can detect the emission of these we can detect the oldest and most extensive emission of these particle jets.

The comparison of the activity seasons of these supermassive black holes and the and the characteristics of the galaxy allow us to infer how they could have impact on the evolution of the galaxy. The approach is to challenge the theory that the more active the black hole, the older the galaxy should be. galaxy. But, above all, the big question that we are trying to answer remains how do black holes influence the galaxies that host them? The link for the original scientific paper is https://rdcu.be/d3ll5