Astronomers find closest black hole to Earth
Meet your new but shy galactic neighbor: A black hole left over from the death of a fleeting young star.
European astronomers have found the closest black hole to Earth yet, so near that the two stars dancing with it can be seen by the naked eye.
Of course, close is relative on the galactic scale.
This black hole is about 1,000 light-years away and each light-year is 5.9 trillion miles.
But in terms of the cosmos and even the galaxy, it is in our neighborhood, said European Southern Observatory astronomer Thomas Rivinius, who led the study published Wednesday in the journal Astronomy & Astrophysics.
The previous closest black hole is probably about three times further, about 3,200 light-years, he said.
The discovery of a closer black hole, which is in the constellation Telescopium in the Southern Hemisphere,
hints that there are more of these out there. Astronomers theorize there are 100 million to 1 billion of these small but dense objects in the Milky Way.
Astronomers found this one because of the unusual orbit of a star. The new black hole is part of what used to be a three-star dance in a system called HR6819. The two remaining super-hot stars aren’t close enough to be sucked in, but the inner star’s orbit is warped.
Using a telescope in Chile,
they confirmed that there was something about four or five times the mass of our sun pulling on the inner star. It could only be a black hole, they concluded.
Outside astronomers said that makes sense.
“It will motivate additional searches among bright, relatively nearby stars,” said Ohio State University astronomer Todd Thompson, who wasn’t part of the research.
Like most of these type of black holes this one is tiny, maybe 25 miles in diameter.