Huge black hole found just a stone’s throw from the Milky Way

It's in the tiny Leo I galaxy, and it has a mass similar to the one at the center of the Milky Way: near our galaxy is a huge black hole

We keep hearing about black holes, and they are among the most fascinating and most unknown cosmic elements. There are more things we ignore than things we know, and science fiction movies have been using them as breakthrough elements for decades. A very peculiar one has recently been discovered.

We think they are very far away, but a recent discovery may cast doubt on even this certainty.

The black hole near the Milky Way

First of all, a clarification is necessary: in astrophysical terms, "near the Milky Way" means incredibly far away and unapproachable, if we translate it into terrestrial terms. This black hole is in fact 820 thousand light years away from us, which is both very close and extraordinarily far away.

It is located in one of the small galaxies that are in the orbit of our Milky Way, Leo I. Leo I is actually part of a collection of microgalaxies called Leo. It seems that inside Leo I there is a giant black hole, similar in size to the one that is at the center of the Milky Way, Sagittarius A*.

Just make some comparisons: Sagittarius A* would have a mass 4.15 million times greater than that of our Sun. A huge object, but tiny when compared to the size of the Milky Way, which is a trillion times the Sun. Leo I is a spherical dwarf galaxy much, much smaller than the Milky Way, yet its black hole is 3 million times the size of the Sun. Slightly less than Sagittarius A*.

"We can't explain why we have such a large black hole in such a small galaxy," said Maria José Bustamante, the scientist leading the study.

Studies by astrophysicists

Surely the scientists didn't expect this discovery, and they weren't looking for it. And they especially didn't expect a black hole of this size.

Leo I has always fascinated scientists because it seems that inside it there is some dark matter, the hypothetical invisible substance that holds galaxies together and wakes scientists up. In fact, the team of astrophysicists has been keeping an eye on Leo I, studying how stars move inside it and how dark matter could be modeled. And instead, the discovery of the black hole.

The study of this black hole is still in its infancy, but according to scientists it is a possible explanation for the growth of supermassive black holes in large galaxies. In fact, galaxies grow by merging with each other, and so do their supermassive black holes. Small galaxies "plummet" into large ones, and their black holes obviously follow them: in this way the mass of the black hole of the larger galaxies increases.

Something that will also happen to two "large" galaxies: the Milky Way and our neighbor Andromeda, which are destined to merge.