By Michael Hernandez
WASHINGTON (AA) – Scientists have discovered a black hole just 1,000 light years from Earth, the European Southern Observatory announced Wednesday.
The black hole, which boasts a mass more than four-times that of our sun, is the closest to Earth known to exist. It was detected in the HR 6819 triple system in the Telescopium constellation.
"An invisible object with a mass at least 4 times that of the Sun can only be a black hole,” observatory scientist Thomas Rivinius, who led the study that was published in the Astronomy & Astrophysics journal, said in a statement announcing the discovery.
The HR 6819 system is so close to the Earth that its two stars can be seen from the southern hemisphere by the naked eye on a clear night.
While its existence has long been known, the black hole was found on closer study of the system as astronomers at the La Silla Observatory in Chile were tracking the system's two stars. One of the stars actually orbits the black hole every 40 days while the other is significantly further from the objects.
Black holes are typically formed on the gravitational collapse of a star.
Unlike most of the others that have been detected, the one in HR 6819 does not react violently with outside matter, the observatory said. Nearly all others of the more than two-dozen black holes that have been detected in our galaxy violently interact with outside matter, releasing powerful X-rays in the process.
“There must be hundreds of millions of black holes out there, but we know about only very few. Knowing what to look for should put us in a better position to find them,” said Rivinius.