This 2023 is fulfilled 60 years of the discovery of the quasars, an astronomical object characterized by a very intense brightness. So much so that it can be compared to a trillion stars packed into the volume of the Solar System. Since then, what science knows about them has come a long way. But there was something that resisted astronomers: how do they light up? The spark that generates this intense glow was a mystery, but it has ceased to be after the publication of an investigation carried out by scientists from the University of Sheffield.
These have shown that quasars are ignited by the collision of two galaxies. In fact, it could be the future of our galaxy, although that is many years away.
For the moment, it seems that they have answered this question that had not been answered for so many decades, but their work is not finished. Now, thanks to telescopes as powerful as the James Webb, it is possible to obtain even more interesting data about quasars and, thus, to know them more thoroughly. It is capable of detecting even some of the most distant quasars, so it will surely provide a lot of information to work with.
Discovered the spark that ignites quasars
This research work has been carried out through the analysis of deep images of the Isaac Newton telescope on La Palma. The astronomers who made it compared 48 galaxies that host quasars with another 100 who have none. Thus, they observed that the former have a much higher probability of colliding with each other. And that gave them the key to the origin of quasars.
It is known that most galaxies have supermassive black holes in its center. Also have large amounts of gas, far enough away from these black holes, so that they are not swallowed. However, if the two galaxies collide, the gas can shoot out into the black hole and, once the event horizon is passed, make a one-way trip into its interior. If this happens, just before the gas is consumed, they would release extraordinary amounts of energy in the form of radiation. And that would be the intense glow that is seen when observing quasars.
The future of our galaxy
This discovery indicates that the ignition of a quasar can have very serious consequences for a galaxy. And it may be the future of our Milky Waysince it is calculated that, within five billion years, it could collide with the galaxy Andromeda.
If that happens, it might not just form quasars. Also, much of the gas in the galaxies would be gobbled up by the black holes, so there would be no raw material left for the formation of new stars. That would be very serious for the planets they host. It could even be terrible for our Earth. However, there is so much time left, that it is possible that, by then, humans themselves have already taken care of ending it.
At least, surely before we will have solved many mysteries like this, that after 60 years finally has an answer.