Trio of Big Black Holes Spotted In Galaxy Smashup

sciencehabit writes Astronomers staring across the universe have spotted a startling scene: three supermassive black holes orbiting close to one another, two of them just a few hundred light-years apart. The trio, housed in a pair of colliding galaxies, may help scientists hunting for ripples in spacetime known as gravitational waves.

Comments

Re:A four million year orbit

[Thanshin]

"What can be more palpably absurd than the prospect held out of locomotives traveling twice as fast as stagecoaches?" - The Quarterly Review, March, 1825.

"That the automobile has practically reached the limit of its development is suggested by the fact that during the past year no improvements of a radical nature have been introduced." - Scientific American, January 2, 1909.

"A rocket will never be able to leave the Earth's atmosphere." - The New York Times, January 13, 1920

"To place a man in a multi-stage rocket and project him into the controlling gravitational field of the moon where the passengers can make scientific observations, perhaps land alive, and then return to earth—all that constitutes a wild dream worthy of Jules Verne. I am bold enough to say that such a man-made voyage will never occur regardless of all future advances." - Lee De Forest, 1957

They are 4.3 billion light-years away. They have already orbited each other a thousand full cycles since the observation (Well, you know what I mean.)
and they will spin another thousand before anything from here can reach them.

Re:Please explain

[Taco Cowboy]

The article states

If the two black holes composing the newfound pair are equally distant from Earth, they're just 450 light-years apart and orbit each other every 4 million years

Can someone explain, or is this a typo? Do they not know if they're the same distance?

I ain't a space scientist, and I hope that what I say is correct --- please correct me if I am wrong --- what TFA is saying is, Black Hole 1 (Point A) and Black hole 2 (Point B) are spinning with each others and we are at a fixed reference point (Point C)

In other words, Point A, Point B and Point C make up a triangle, with Point A and Point B spinning with each other.

What TFA suggests is that when Black Hole 1 (Point A) and Black Hole 2 (Point B) happens to link to the fixed reference point (Point C) in which the distance of AC = BC , the distance of AB = 450 Light Years

As I have said, I ain't a space scientist, if I am incorrect, please correct me, thank you !