Astronomers consider that there are about 100 million black holes in the Milky Way and that all galaxies have at least one black hole at their center that emits radiation in the form of gamma rays.
Black holes contain such a high concentration of mass that they generate a powerful gravitational field: they absorb everything they trap, including light.
They are all far enough away that they can devour the Earth at some point, although the gamma-ray bursts they generate could affect life on Earth, according at NASA.
Of all the possible black holes in our galaxy, astronomers have identified a total of 14, of different masses, which are located in the vicinity of our solar system and, therefore, of the Earth.
The closest black hole to Earth is part of a binary system known as A0620-00, located in the constellation Monoceros (Unicorn), 3,457 light years from Earth.
A0620-00 is especially well known because it will be the first black hole to receive human interaction. Its mass is 3.2 times that of the Sun.
From the European Space Agency at the Cebreros Station (Madrid), a radio signal was broadcast in 2018 with a message of peace and hope in memory of Stephen Hawking, that will reach its destination in the year 5475. It will then become a form of energy predicted and named in his honor: Hawking’s Radiation, stand out the BBC.
A much larger black hole, 1,300 times the solar mass, also close to us, is Sagittarius A * (Sgr A *). It is in the very center of the Milky Way, 26,000 light years from our Sun, surrounded by a series of strange objects that behave like stars.
More cases There are more black holes identified. HR 6819 is a double or triple star system in the southern constellation Telescopium, believed to include the closest supermassive black hole to the Sun.
This star system is about 250 light years from our star, from which it is moving away at a speed of 9.4 kilometers per second.
There is another no less relevant star, known as V723 Monocerotis, located 979.47 light years from Earth, which is accompanied by another black hole that they have called Unicorn, according to just reveal.
Another candidate for a black hole near the solar system is found in the gamma-ray and X-ray source GRS 1124-683 (GU Muscae), considered one of the possible black holes that are classified as new X-rays. This black hole is about seven times more massive than the Sun, which is 315 light-years away.
Another binary system, known as XTE J1118 + 480, is in the constellation Ursa Major, located about 80 light years from our solar system.
It probably contains a black hole that is considered to be a micro quasar, the compact region that surrounds a stellar black hole. XTE J1118 + 480 is the first system X-ray black hole firmly identified in the galactic halo.
Swan Concentration In the constellation of the Swan, 5,500 light years from Earth, we have several cases: the first, Cygnus X-1, a galactic X-ray source that was the first source of its kind widely accepted as a black hole.
In the same constellation there is also V404 Cygni, a micro quasar and a binary system that contains a hole with a mass that is approximately nine times that of our Sun, which is separated by 460 light years.
The constellation of Swan is finally home to Cygnus X-3, a high mass binary X-ray system that represents one of the strongest binary X-ray sources in the sky.
The components of this binary system are not precisely known, but it is believed that one of them will turn into a black hole very quickly, on astronomical timescales.
Nebulae and constellations
Nebulae and constellations The list of identified black holes continues in other regions. In the Crab Nebula, 6,523 light years from Earth, is GRO J0422 + 32, an X-ray nova and black hole candidate since its discovery in 1992.
The mass of the black hole in GRO J0422 + 32 is around five times that of our Sun, and it is the smallest ever found for any stellar black hole. There are still doubts about what it really is.
In the constellation Vulpecula, about 300 light years away, is GS 2000 + 25, a binary X-ray system consisting of a late K-type star and a black hole with a mass five times that of our Sun.
Also found in the constellation Scorpio is GRO J1655-40, a binary star located about 11,000 light years from our Sun, consisting of an evolved primary star and an invisible massive companion that appears to be a stellar black hole with several times the mass of the Sun. Both move through the Milky Way at about 70 miles per second.
Finally, in the constellation Lupus, 2,000 light-years from Earth, is 4U 1543-475, an X-ray transient that is a member of a black hole binary that was first observed in 1971.
It is a frightening panorama on the one hand, considering the potential dangers, but at the same time hopeful, because black holes possess enormous amounts of energy that one day, perhaps, we will know how to take advantage.
Top photo: Simulation of a supermassive black hole capturing light and creating its characteristic silhouette. Credit: NASA Goddard Space Flight Center; ESA / Gaia / DPAC background image.
Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.