Did you know that the Milky Way has a bar? Galaxies evolved surprisingly quickly in the young universe – VTM.cz

Anyone who has ever encountered astronomy has surely noticed that galaxies are very varied, but at the same time they only occur in a few basic types of shapes. Today, there are essentially four types – spiral galaxies, barred spiral galaxies, elliptical galaxies and irregular galaxies.

Barred spiral galaxies, which include our own Milky Way, were until recently considered to be a modern type of galaxy, into which galaxies take a long time to evolve. Astronomer Zoe Le Conte of the UK’s University of Durham and her colleagues followed up on earlier research with the Hubble telescope and used the Webb telescope to investigate the evolution of barred spiral galaxies.

Example of a galaxy with a bar: the galaxy NGC 1300. The bar indicates that the galaxy is relatively stable.

They managed to discover bar-type structures in galaxies observed in the universe, which was then less than 3 billion years old. From these observations, they conclude that galaxies evolved surprisingly quickly and that barred galaxies appeared in the universe much earlier than previously thought.

Experts suspect that galaxies are not immutable. First, they had to come into existence somehow. And then they also undoubtedly evolve over time, on a scale of hundreds of millions and billions of years. There are actually a lot of barred galaxies in the universe. According to current estimates, about two-thirds of the spiral galaxies in the local, i.e. in the nearby, not very old universe, have a bar.

According to past observations, the number of barred galaxies decreased drastically when observing a more distant and thus younger universe. But the Webb telescope offered new possibilities. Compared to the Hubble telescope, it can see further and detect more detailed structures. The researchers examined 368 galaxies from Webb’s recent observations of the very distant universe, looking for bar structure.

They found that the number of barred galaxies, as expected, decreases with the age of the universe, i.e. with increasing distance from us, but at the same time there are significantly more of them than expected. The results show that barred galaxies began to develop unexpectedly early in the universe. The evolution of the bar in galaxies is very important to scientists because they believe it is the key to understanding the evolution of galaxies as such.

Source: Universe Toda