Just like a cake, a planet needs the perfect ingredients and conditions for humans to survive.

From the right amount of gravity and the right temperature, to essential ingredients like water, oxygen and food.

Planet Earth is in the "Goldilocks Zone" which means it's not too hot and not too cold, making it just right for life. Unlike Venus which due to its thick and poisonous atmosphere it's the hottest planet in the Solar System or Jupiter which is so big its gravity would squash us instantly.

But with a universe full of planets and possibilities, the search for life beyond Earth is really just getting started...

Why does chocolate melt? Where does wind come from? How do we know dinosaurs actually existed? Curious kids can discover the answers to hundreds of the biggest questions about science and the world around them.

Why Is the Sky Blue?

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