What are comets and asteroids and where do they come from?
Cosmic Leftovers
What are comets and asteroids and where do they come from?
Imagine the solar system threw a big party four and a half billion years ago, made all the planets, and then... forgot to clean up. Comets and asteroids are the leftovers — the crumbs and chunks that never got swept into a planet. They've been drifting out there ever since, exactly the same age as Earth, just a lot less tidy.
Let's meet the asteroids first. They're basically space rocks — some the size of a pebble, some bigger than a mountain. They're made of stone and metal, dry and dusty, the kind of thing that would clunk if you knocked on it. Think of them as boulders that never found a home.
