What are stars?

Stars are giant balls of hot gas that shine in the sky because they’re burning.

Imagine you have a really big balloon filled with fire, that’s kind of what a star is like! Just like how your favorite toy lights up when it’s turned on, stars light up because they’re super hot and glowing.

Stars are made mostly of hydrogen, which is the same stuff inside your water bottle (but way more powerful!). When hydrogen gets squeezed really tight, like when you press down hard on a balloon, it starts to change into another kind of gas, helium. This change makes lots of energy, and that’s what causes stars to shine.

Stars are so big because they have so much gravity, which is like the invisible glue that holds things together. Think of gravity as a strong hug, it pulls everything in the star toward the center, making it burn even brighter!

Sometimes, when a star runs out of hydrogen fuel, it can puff up and become a red giant, kind of like how your face gets red when you're really hot from running around!