Question: How many black holes is their

Bella Boulderstone answered on 20 Jun 2019:

This isn’t quite my area because there are a whole bunch of stellar mass black holes (10-50x the mass of our sun) in each galaxy at any given time (this website: http://hubblesite.org/explore_astronomy/black_holes/encyc_mod3_q7.html gives a good estimate that there are 100 million black holes in our galaxy alone). There are billions of galaxies, but also, there’s a supermassive black hole at the centre of most galaxies. So for each galaxy, there’s a 100 million black holes so that’s about 100 million billion(s) black holes.

Space gets really big, really really fast.