Are we in the 'Solitude Zone' of the universe?

Are we alone? It's one of the most basic questions of human existence. People have been trying to answer it for millennia in one form or another, but only recently have we gained the tools and knowledge to start tractably ...

How a nutrient spark turned Earth into an oxygen world

A new study has revealed how phosphorus, a nutrient essential for photosynthesis, surged into ancient oceans and started Earth's first major rise in atmospheric oxygen more than 2 billion years ago.

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