Here's a fun fact: supermassive black holes are thought to be at the centre of most galaxies. They're integral to their formation, with both galaxy and black hole evolving together, possibly having some kind of cosmic symbiotic relationship. But just how massive is supermassive?
This #mindblown video from YouTube user morn1415 will give you some idea, putting their enormity into some kind of perspective. Although anything multiplied thousands of times is hard for your brain to grasp beyond anything other than WHOAH.
morn1415 tells us that a mid-range black hole has the mass of oh, say, a 1000x of our Sun. Now that's big, but it's nothing compared to the behemoth at the center of the Phoenix Cluster, one of the largest galaxy clusters we know of in the universe. That has a central black hole that has a mass of billions of suns. BILLIONS!
This Eric Wareheim GIF is going to sum up how you're feeling right now.
The weird thing is, because of the nature of black holes and the fact that they don't emit any light, it's really hard to capture or record one. But here's some artistic representations and other images from NASA to give you some visuals.
Here's NASA talking about how black holes "feed": At the center of spiral galaxy M81 (below) is a supermassive black hole about 70 million times more massive than our sun.
A study using data from Chandra and ground-based telescopes, combined with detailed theoretical models, shows that the supermassive black hole in M81 feeds just like stellar mass black holes, with masses of only about ten times that of the sun.
This discovery supports Einstein's relativity theory that states black holes of all sizes have similar properties.
And if your mind isn't sufficiently in ruins after all that, then have a watch of another of morn1415's videos where he compares star sizes.