Little "Hedgehog": astronomers may have found the loneliest galaxy in the universe (photo)

Astronomers have discovered what may be the loneliest galaxy in the universe, nicknamed "Hedgehog." Officially, this dwarf galaxy is designated as dw1322m205 and is located 7.8 million light-years away from us. It is several million light-years distant from its nearest neighbors, and star formation has ceased within it. The study was published in The Astrophysical Journal Letters, reports IFLScience.

Astronomers were searching for dwarf galaxies orbiting the galaxy NGC 5068 when they stumbled upon a completely new, previously unknown object, which is the dwarf galaxy dw1322m205. Calculations revealed that this galaxy is 7.8 million light-years from Earth and is indeed very solitary. It turns out that it is separated from the nearest galaxy by 3.3 million light-years and from the closest group of galaxies by 2.2 million light-years.

The galaxy dw1322m205 has been given the nickname "Hedgehog," not because it resembles the animal, but because, according to astronomers, hedgehogs are small and solitary creatures.

This new galaxy is significantly smaller compared to other similar objects, with a mass only 630,000 times greater than that of the Sun. For comparison, the mass of our galaxy is hundreds of billions of times that of the Sun.

Many dwarf galaxies have long ceased the process of forming new stars. This is due to interactions with larger galaxies, which have stripped away the necessary gas for star formation.

On the other hand, only 6 out of 10,000 known isolated dwarf galaxies, such as "Hedgehog," have stopped forming new stars. The reason is that there are no large neighbors nearby that could remove gas from the galaxy, allowing the star formation process to continue.

Astronomers have not found any young stars or dust in the galaxy dw1322m205 that could be obscuring them. The study suggests that new stars have not formed in this galaxy for at least 100 million years, and possibly for as long as 5 billion years.

Currently, astronomers aim to understand the reasons behind the cessation of star formation in the "Hedgehog" galaxy. Scientists believe that the galaxy likely lost a significant portion of its gas when it passed through a galaxy group, and was subsequently ejected into the void of space by the gravity of larger galaxies.

Calculations indicate that if dw1322m205 were ejected by the group of galaxies closest to it, it would have taken 4–6 billion years to reach its current position.

It is also possible that the dwarf galaxy lost a large amount of gas through some other means, such as a low number of supernova explosions.