The story of Earth: How it formed and why it’s unique

Our little blue planet in the Milky Way is truly one of a kind 

Image by PIRO4D from Pixabay

As far as scientists know, Earth is the only living planet in the galaxy.

Born 4.6 billion years ago from a cloud of cosmic dust and gas, our 7,917.5-mile-diameter ball of rock is home to nearly 9 million different species – and has hosted many more millions since life began. The amount our planet has achieved over its relatively short life span is astonishing. But its journey from a lifeless rock to a paradise island in the cosmos hasn’t been easy.

Earth wasn’t one of the first planets in the universe – in fact, it’s relatively young. Our Sun is a second-generation star, one of a group called Population I. It was born out of the remnants of much older stars after they ran out of fuel.


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