Black holes

[George Reilly]

All Galaxy's have black holes,is there any that have more than one.

[Blaid Drwg]

1 hour ago, George Reilly said:

All Galaxy's have black holes,is there any that have more than one.

Yep saw a docu earlier this week about twin black holes who are in the process of merging. 

 

[George Reilly]

Great info,Thanks for speedy reply

[Waspie_Dwarf]

7 hours ago, George Reilly said:

All Galaxy's have black holes,is there any that have more than one.

It is worth pointing out that there are more than one type of black hole. The type I suspect you are thinking of are supermassive black holes. These can have a mass ranging from hundreds of thousands to billions of times that of the sun. They were formed early in the history of the universe by processes not yet fully understood. These are the black holes you find at the centres of many galaxies. They are usually solitary but are sometimes found in pairs (see this article from a few days ago: Elusive Giant Black Hole Pairs Found).

Incidentally not all galaxies have supermassive black holes at the centre.

Then there are the stellar-mass black holes. These have a mass of 5 to tens of times greater than the sun. These are being formed all the time as a result of the gravitation collapse of stars, an event that leads to some types of supernova. Since galaxies can contain billions of stars, they can contain many thousands of stellar-mass black holes.

Hypothetically there should be a class of black holes between the stellar-mass and the supermassive, known (imaginatively) as intermediate mass black holes. These are, however, proving to be very elusive.