Active galactic nucleus

An active galactic nucleus is like a super powered light bulb that's at the center of a really big galaxy. Imagine if you took a flashlight and put it in the middle of a big room. When you turn it on, it lights up the whole room. That's what an active galactic nucleus does - it lights up the galaxy around it.

But instead of light, an active galactic nucleus gives off a ton of different kinds of energy, like X-rays and gamma rays. This energy is made by really hot stuff that's swirling around a supermassive black hole at the center of the galaxy.

Think of the black hole like a drain in a bathtub. When you take a bath, the water swirls around and goes down the drain really fast. In the same way, gas and other stuff swirl around the black hole at incredibly high speeds. This creates a lot of heat and energy that we see as an active galactic nucleus.

Scientists study active galactic nuclei because they can tell us a lot about how galaxies form and evolve over time. They're kind of like giant laboratories in space that help us learn more about the universe!