James Webb discovers a galaxy too far away
Being able to observe very distant objects is quite interesting, because we can have an idea of what they were like when they were born. That is one of the functions of James Webb, the latest rock star of space telescopes. However, he has just made a most curious discovery, because he has found a galaxy far away which, despite that, looks much older than it should be with the current knowledge of astrophysicists.
This means that, with what is known today about the physics of the birth of galaxies, that very distant galaxy should not exist. It doesn’t make sense for it to be so big and so old and be so far away.
The scientists responsible for its discovery, just published in Nature, have explained in a statement that they have been behind this galaxy for 7 years. They were using the two largest telescopes on Earth: the Keck and the Very Large Telescope (VLT), but they were not enough to analyze this object in depth. It has been necessary to wait for something as novel as the James Webb to have that information that turns upside down what scientists know so far about galaxies.
Why is the discovery of this distant galaxy so rare?
When we look at an object very far away, we are not seeing how it looks now, but rather how it did. billions of years ago. This is because it is necessary for its light to reach us. Being so far away, the light that reaches us does not just come out, but was emitted a long time ago, when the object was much younger.
In the case of this distant galaxy, named ZF-UDS-7329 it is known that its light has been slow to arrive 11.5 billion years. However, thanks to infrared measurements from James Webb, it has been possible to observe that its stellar population was already there. 1.5 billion years ago.
That stellar population is enormous. In fact, it is calculated that the mass of all its stars is, at least, twice that of our Milky Way. And this is where the inconsistencies begin. It has taken our galaxy billions of years to have that stellar population. To achieve twice the mass, much more would be needed. That would indicate that, in reality, this distant galaxy was more than 1.5 billion years old when its light left for James Webb. Or that it somehow follows an unknown training method that allows it to grow in size much faster than normal. Whatever the answer, it challenges the known science around galaxy formation.
A question of dark matter
Dark matter is one of those great mysteries of science. Is calculated which constitutes approximately the 27% of the matter in the universe, but it is incapable of emitting any type of electromagnetic radiation. It also does not interact with any type of nearby radiation. That makes it a mystery to telescopes, since they cannot detect it.
Although not much is known about it, dark matter is considered to have a fundamental role in evolution of galaxies. With current knowledge about these star formations, it is assumed that, in the case of the rarity found by James Webb, enough dark matter could not have accumulated to give rise to such a large galaxy in such a short time.
Therefore, there are two possible errors. Or those accumulations of dark matter They do not occur in the way previously believed, or there is something in the formation of galaxies that escapes the scientists who study them.
In fact, although this is especially unusual, it is not the first rarity of this type to be detected. Continuing research along these lines could change the science known so far. Dark matter is once again a little darker in the eyes of those who study it, but that makes this new finding especially interesting.