This is newbie. A galaxy so transparent that no one noticed it for years

If galaxies visible in observational data from decades ago were described as hazy objects, then Nobi's is a haze so fine it may be unobservable. The best evidence for this is that although this part of the sky has been observed many times before, the galaxy has remained unnoticed until now. This is mainly because it looks so spread out, you actually have to look closely to see the galaxy there in the images.

Although over the past century scientists have observed thousands of galaxies of different shapes, Nobby was surprised by its appearance. We are dealing here with a dwarf galaxy that is ten times dimmer than objects of the same type. Furthermore, Nobi is ten times larger than other dwarf galaxies containing the same number of stars. Astronomers point out that the galaxy itself has a mass similar to that of the Small Magellanic Cloud. However, all this mass extends to a size similar to a third of the Milky Way. So it is not surprising that this galaxy, like a transparent ghost, remains invisible in most sky surveys.

So, it should come as no surprise that no one noticed Nube before. First of all, scientists did not suspect the existence of such scattered galaxies, so no one looked for them. The discovery happened by chance While analyzing images from the Sloan Digital Sky Survey (SDSS). A blurry spot observed in one of the images caught the attention of scientists, who decided to take a closer look at it using the Gran Telescopio Canarias (GTC). Only then did it turn out to be a very sparse galaxy. But its elusive structure did not allow scientists to determine its distance. Only observations made with the GBT telescope allowed us to estimate that we are about 300 million light-years away.

However, the galaxy itself poses a major challenge to scientists searching for dark energy. Unlike most known galaxies, the density of Nubi stars does not decrease towards the outer regions, but remains approximately the same throughout the galaxy. For this reason, the galaxy has not been observed before. Moreover, it has been shown that no cosmological simulations based on the currently accepted cosmological model, which takes into account the presence of cold dark matter, are able to reproduce the structure of this galaxy.

Astronomers admit that the Nube Galaxy's distinct properties can tell us a lot about the dark matter itself that must hold the galaxy together. The researchers speculate that Knobby's structure indicates that dark matter particles have a very low mass. Moreover, if this is the case, says Ignacio Trujillo, one of the authors of the discovery, then the properties of the galaxy itself could exhibit properties of quantum physics on a galactic scale. That would be a really cool thing. So we can be sure that we will hear about Nube more than once.