M–sigma relation

The m-sigma relation is a rule that scientists have observed about the way supermassive black holes (really, really big black holes) work. Basically, what they found was that the bigger a supermassive black hole is, the faster the stars around it move.

Here's an example to help you understand: Imagine you're sitting on a roundabout, and you're spinning slowly. If someone pushes you gently, you won't go very fast. But if they push you really hard, you'll go really fast. That's kind of like what happens around a supermassive black hole – the stars are like you on the roundabout, and the black hole is like the person pushing.

Scientists measure how fast those stars are moving, and they use something called "sigma" to do it. It's like a math word that tells you how spread out something is. When scientists look at the stars around supermassive black holes, they can measure sigma and they can also measure how big the black hole is (by looking at how much stuff it's sucking in, basically).

What they found was that the bigger the black hole, the faster the stars are moving – and the relationship between the two is really predictable. It's kind of like if you knew how much your roundabout was spinning and how hard someone was pushing you, you could predict exactly how fast you'd go around. Scientists use the m-sigma relation as a way to understand how supermassive black holes work, and it's helping them learn more and more about these mysterious, gigantic objects in the universe.