ELI5: Explain Like I'm 5

Ring galaxy

Have you ever seen a cookie with a hole in the middle? A ring galaxy is like that cookie, it has a hole in the middle. But instead of being made of cookie dough and chocolate chips, a ring galaxy is made of gas, dust, and stars.

Imagine you are playing with marbles and you push them all together into a big bunch. Now, pretend you saw a big explosion right in the middle of the marbles. All the marbles would be flung out, some would go far away, and some would stay close together.

That's kind of like what happens with a ring galaxy. A long time ago, something big happened in the middle of the galaxy, maybe two galaxies crashed into each other, or maybe some stars exploded. Whatever it was, it caused a big disturbance that pushed a lot of the stars and gas out to the sides of the galaxy.

The stars and gas that were pushed out, formed a big ring like a doughnut around the center of the galaxy. This ring can be seen as a bright collection of stars and gas in the shape of a circle surrounding a dark empty space in the center of the galaxy.

Scientists are still trying to figure out why these ring galaxies form and what they can tell us about how galaxies grow and evolve. But for now, we can enjoy looking at these beautiful and unique galactic doughnuts in the night sky.