What are huge balls of gas?

Huge balls of gas are just really big versions of things we see every day, like bubbles or balloons.

Imagine you're blowing up a balloon, as you blow more air into it, it gets bigger and bigger. Now imagine doing that a lot, not with air, but with super hot stuff that's always moving around inside the balloon. That’s what makes stars, they’re like giant, glowing balloons full of very hot gas.

Inside a star, there's a lot of gas, and it's so hot that the gas is actually burning, not with fire, but with something called nuclear reactions. This burning keeps the star bright and warm, just like how a campfire keeps you warm on a cold night.

Some stars are so big that if one were right next to Earth, it would cover our whole planet! Others are smaller, some are even about the same size as our Sun. But no matter their size, they’re all just huge balls of gas doing their best to shine in the night sky.