Astronomers may have found the smallest galaxy ever

There is a small group of stars orbiting our Milky Way Galaxy. It should have actually been torn apart by the Milky Way a long time ago. The fact that they are still there indicates that a large amount of dark matter holds the stars together.

A small group of stars orbits the Milky Way without being refracted. This may be the smallest galaxy ever observed. Although the cluster consists of only 57 stars, it may be full of dark matter.

This strange cluster is called Ursa Major III/UNIONS 1. It orbits our galaxy, about 33,000 light-years from Earth. It is the smallest and faintest satellite galaxy of the Milky Way ever discovered.

Two options

astronomer William Cerny The satellite was discovered by his colleagues at Yale University as part of a project called… Northern Optical Survey UV-Near-Infrared. In this project, the team is using several large telescopes in Hawaii to image wide swaths of the sky. After this discovery, they made subsequent observations using the Keck 2 telescope in Hawaii. They published their results in the scientific journal Astrophysical Journal.

Astronomers discovered that the stars in the star cluster have a mass of about sixteen times the mass of the Sun. This corresponds to about 57 relatively small stars.

“Its mass is so low that the Milky Way should have torn it apart,” Cerny says. “The fact that this didn't happen means that this thing is either a galaxy or a galaxy.” Star cluster Which we see in a very special moment, just before his death.

The thinnest and smallest galaxy

If the star cluster is indeed a galaxy, this means it must be filled with dark matter. This material provides the gravity needed to hold the stars together. Further analysis showed that if such dark matter existed, it would need to be about a billion times the mass of the Sun to explain the speeds of stars in the galaxy.

If the object is a star cluster, it is unlikely to exist for more than 400 million years. However, current observations suggest it is a galaxy, Cerny said. “It will be the thinnest and smallest known galaxy in the entire universe,” he says. More precise measurements of stars, along with observations of other similar objects, should provide greater clarity.