What is Stellar evolution?

Stellar evolution is what happens to stars as they grow old and change over time.

Imagine you have a giant balloon, and it's full of hot air, that’s like a new star. At first, the balloon is bright and warm, just like a baby star. Over time, the balloon starts to cool down and lose air, that’s like how a real star changes as it gets older.

How stars change

At first, a star burns brightly by turning hydrogen into helium inside its core, kind of like how your body turns food into energy. But once most of the hydrogen is gone, the star starts to change shape and get bigger or smaller, depending on how big it was at first.

Some stars end up as gentle old giants, while others explode in a bright supernova before becoming tiny, dense white dwarfs, like going from being a bouncy kid to a quiet grandpa.

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Examples

  1. A star is like a person, it's born, lives its life, and eventually dies in a dramatic explosion or quiet fade.
  2. Our sun will one day become a red giant before shrinking into a white dwarf.
  3. Stars can explode as supernovas, creating new elements that help form planets and even people.

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Categories: Culture · stars· astronomy· cosmos