Amazing stuff!
"Astronomers studying the murky center of our Milky Way galaxy have discovered something they never expected: a pair of young stars orbiting each other near the supermassive black hole that is our galaxy’s dark heart. The observation comes as a surprise because astrophysicists had thought that the black hole’s intense gravity would either rip the stars in such a pair apart or squash them together.
The supermassive black hole at the galaxy’s center has a mass four million times that of the Sun; a dense cluster of stars buzzes around its edge. Many of them are old stars that migrated there over billions of years, but others are unexpectedly young and it is not known how they got there. The newest member is D9, discovered by astronomers using the European Southern Observatory’s Very Large Telescope. They noticed that its light shifted back and forth in frequency in a regular way every 372 days, just as happens with binaries as the orbiting stars move toward and away from Earth, Doppler-shifting their light. They concluded that within its dusty shroud, D9 hides a star just 2.7 million years old with 2.8 times the mass of our Sun and a companion of just 0.7 solar masses. ..."
"“Black holes are not as destructive as we thought,” ... Binary stars, pairs of stars orbiting each other, are very common in the Universe, but they had never before been found near a supermassive black hole, where the intense gravity can make stellar systems unstable.
This new discovery shows that some binaries can briefly thrive, even under destructive conditions. D9, as the newly discovered binary star is called, was detected just in time: it is estimated to be only 2.7 million years old, and the strong gravitational force of the nearby black hole will probably cause it to merge into a single star within just one million years, a very narrow timespan for such a young system. ..."
Young double-star system discovered near our Galaxy’s giant black hole (open access) "Surprising find could force rethink of astrophysics at Milky Way’s center"
First ever binary star found near our galaxy’s supermassive black hole (original news release, contains link to research paper)
An international team of researchers has detected a binary star orbiting close to Sagittarius A*, the supermassive black hole at the centre of our galaxy. It is the first time a stellar pair has been found in the vicinity of a supermassive black hole. The discovery, based on data collected by the European Southern Observatory’s Very Large Telescope (ESO’s VLT), helps us understand how stars survive in environments with extreme gravity, and could pave the way for the detection of planets close to Sagittarius A*.
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