What Makes a Galaxy Spiral or Elliptical?

A galaxy can be spiral or elliptical, depending on how its stars and dust move and arrange themselves.

Imagine you're playing with a toy train set. If the train goes around in circles, like it's following a track that loops and curves, that’s like a spiral galaxy. The stars are moving in a twisty path, kind of like the train on its curvy track. You can see arms stretching out from the center, just like how a spiral staircase has steps going up around a central pole.

Now, if you have two toy trains running on straight tracks that cross each other, and they crash into one another or move together in a squishy bunch, that’s more like an elliptical galaxy. The stars don’t go in neat loops; they move more like the train cars bumping into each other, making a round or oval shape.

When galaxies are born, their shapes depend on how fast they spin and what happens when they meet others. A spiral galaxy spins quickly, keeping its stars in tidy, curvy paths. An elliptical galaxy might have had a big crash with another galaxy, like two toy trains smacking together, making everything move more randomly.

So whether it’s twisty or squishy, it all starts with how the stars dance and bump around.