A black hole 20,000 times bigger than the Sun
July 14, 2024 7:37 AM Subscribe
A black hole 20,000 times bigger than the Sun could help us understand how galaxies evolved.
Astronomers catalogued 1.4 million stars to find the black hole, 18,000 light-years from our Solar System, in the Milky Way.
It's amazing how we've gone in a few decades from black holes being "exotic" objects to things that you'll find in every stellar neighborhood and at the core of every galaxy.
posted by credulous at 9:33 AM on July 14 [3 favorites]
posted by credulous at 9:33 AM on July 14 [3 favorites]
...18,000 light-years from our Solar System, in the Milky Way.
Ah! That’s where I put it.
posted by Thorzdad at 9:39 AM on July 14 [1 favorite]
Ah! That’s where I put it.
posted by Thorzdad at 9:39 AM on July 14 [1 favorite]
Black holes are the drains every galaxy in circling.
posted by pracowity at 9:53 AM on July 14 [2 favorites]
posted by pracowity at 9:53 AM on July 14 [2 favorites]
Black holes are the drains every galaxy in circling.
I'm sure you were being poetic or metaphorical but it seems that many people literally believe something like this is true, that galaxies are either being slowly sucked into their supermassive black holes or at least the entire galaxy is gravitationally bound to and revolving around the black hole in the same way that the Earth revolves around the sun.
But the Milky Way's central black hole (Sagittarius A*) is equivalent in mass to "only" about 4.1 million Suns, whereas the total weight of all the stars in our galaxy is about 46 billion Suns or more. And for the entire galactic mass we'd need to include the dark matter which adds an order of magnitude, 10x or more. So the center is tiny compared with the entire galaxy. It's completely different to a solar system where the star at the center is 99% of all the mass. We're no more specifically attracted to Sagittarius A* than we are to some random patch of 4.1 million stars elsewhere in the galaxy. (Although we do revolve around the galactic center because the entire galaxy is gravitationally bound to itself.) And the black hole at ω Cen is much, much smaller than Sgr A*. And, btw, the closest known black hole to us is Gaia-BH1, only 1,560 light years away. We could literally travel there by Airbus A320 in just around 2 billion years!
posted by xigxag at 12:30 PM on July 14 [4 favorites]
I'm sure you were being poetic or metaphorical but it seems that many people literally believe something like this is true, that galaxies are either being slowly sucked into their supermassive black holes or at least the entire galaxy is gravitationally bound to and revolving around the black hole in the same way that the Earth revolves around the sun.
But the Milky Way's central black hole (Sagittarius A*) is equivalent in mass to "only" about 4.1 million Suns, whereas the total weight of all the stars in our galaxy is about 46 billion Suns or more. And for the entire galactic mass we'd need to include the dark matter which adds an order of magnitude, 10x or more. So the center is tiny compared with the entire galaxy. It's completely different to a solar system where the star at the center is 99% of all the mass. We're no more specifically attracted to Sagittarius A* than we are to some random patch of 4.1 million stars elsewhere in the galaxy. (Although we do revolve around the galactic center because the entire galaxy is gravitationally bound to itself.) And the black hole at ω Cen is much, much smaller than Sgr A*. And, btw, the closest known black hole to us is Gaia-BH1, only 1,560 light years away. We could literally travel there by Airbus A320 in just around 2 billion years!
posted by xigxag at 12:30 PM on July 14 [4 favorites]
The best-fit mass of the black hole in omega Centauri (a weird globular cluster within the Milky Way that is widely believed to be the stripped nucleus of an accreted dwarf galaxy) is actually more like 40,000 solar masses according to the original Nature article.
The actual size of such a black hole is less than the size of the sun -- the radius of a 40,000 solar-mass black hole would be about 1/7th the radius of the sun.
posted by heatherlogan at 1:38 PM on July 14 [4 favorites]
The actual size of such a black hole is less than the size of the sun -- the radius of a 40,000 solar-mass black hole would be about 1/7th the radius of the sun.
posted by heatherlogan at 1:38 PM on July 14 [4 favorites]
Can it hurry up and get here?
posted by senor biggles at 2:12 PM on July 14 [1 favorite]
posted by senor biggles at 2:12 PM on July 14 [1 favorite]
Yeah, it's an odd use of "bigger" in this article. I don't think most people would describe a bowling ball as many times "bigger" than a beach ball, just because it's much heavier. But it's a cool discovery!
posted by biogeo at 3:06 PM on July 14 [1 favorite]
posted by biogeo at 3:06 PM on July 14 [1 favorite]
... only 1,560 light years away. We could literally travel there by Airbus A320 in just around 2 billion years!
Unfortunately, Airbuses only work where there is air. We'd need a Spacebus. ;)
posted by heatherlogan at 3:21 PM on July 14 [5 favorites]
Unfortunately, Airbuses only work where there is air. We'd need a Spacebus. ;)
posted by heatherlogan at 3:21 PM on July 14 [5 favorites]
Airbuses only work where there is air.
But that's just an engineering problem. We'd only need to fill up the flight path to Gaia-BH1 with 0.2 atm cruising altitude density air until the plane is far along enough for its 830 kph/230 mps cruising speed to be the escape velocity from the Sun at that distance, at which point we can turn off the jet engines and just coast the rest of the way on inertia. My dodgy online maths say the escape velocity will decrease down to cruising speed at only about 0.26 light year distance from the sun, requiring the flight path filled up to that point with 0.66 quintillion kg of air. More I reckon if we want the luxury of the flight column being wider than the exact wingspan of the Airbus. Like I suppose we might want some long pressurized tube to contain the atmosphere. But even so, we're talking a number comfortably under of the 5 quintillion kg of air the Earth's atmosphere provides for the project . So in other words, eminently doable!
posted by xigxag at 6:58 PM on July 14 [3 favorites]
But that's just an engineering problem. We'd only need to fill up the flight path to Gaia-BH1 with 0.2 atm cruising altitude density air until the plane is far along enough for its 830 kph/230 mps cruising speed to be the escape velocity from the Sun at that distance, at which point we can turn off the jet engines and just coast the rest of the way on inertia. My dodgy online maths say the escape velocity will decrease down to cruising speed at only about 0.26 light year distance from the sun, requiring the flight path filled up to that point with 0.66 quintillion kg of air. More I reckon if we want the luxury of the flight column being wider than the exact wingspan of the Airbus. Like I suppose we might want some long pressurized tube to contain the atmosphere. But even so, we're talking a number comfortably under of the 5 quintillion kg of air the Earth's atmosphere provides for the project . So in other words, eminently doable!
posted by xigxag at 6:58 PM on July 14 [3 favorites]
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...but the third black hole was juuuust right.
posted by AlSweigart at 9:21 AM on July 14 [5 favorites]