Timeline of the Big Bang
The Big Bang happened a really, really long time ago. It was like the start of the universe. All of the stars and planets started from the Big Bang. It all happened in a big explosion, so it was really loud and bright. The Big Bang happened about 13.8 billion years ago, so that's a really big number! After the Big Bang, the universe kept getting bigger and bigger until it is as big as it is today.
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