New details on black hole
WASHINGTON: A fresh examination has revealed new details about the first black hole detected — which was spotted in 1964 and became the subject of a friendly wager between renowned scientists — including that it is bigger than previously known.
Researchers say new observations of the Cygnus X1 black hole, orbiting in a stellar marriage with a large and luminous star, showed it is 21 times our sun’s mass, about 50% more massive than previously believed.
While it is still one of the closest known black holes, they found it is farther away than previously calculated, at 9.5 trillion km from Earth.
Black holes are extremely dense, with gravitational pulls so ferocious not even light escapes. Some — the ‘‘supermassive’’ black holes — are immense, like the one at our Milky Way galaxy’s centre, four million times the sun’s mass. Smaller ‘‘stellarmass’’ black holes possess the mass of a single star.
Cygnus X1 is the Milky Way’s largestknown stellarmass black hole and among the strongest Xray sources seen from Earth.