Earth Is the Solar System’s Only Known Place With Ordinary Fire

Earth is the only known place in our solar system where ordinary fire occurs, and no known exoplanet has enough oxygen for it.

Astronomy

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Fire seems ordinary on Earth, but ordinary combustion is surprisingly unusual from an astronomical point of view. So far, Earth is the only known place in our solar system where naturally occurring open fire has been observed. The key ingredient is not simply heat. Fire needs a fuel and an oxidizing environment that can keep a rapid chemical reaction going. On modern Earth, oxygen in the atmosphere makes this familiar kind of combustion possible. Earth did not always have an oxygen-rich atmosphere, though. Oxygen accumulated much later as photosynthetic life released it, eventually reaching levels that could support widespread combustion. The claim also needs a little care: oxygen is not the only possible oxidizer, so fire is not fundamentally limited to oxygen-rich worlds. Other chemicals can drive combustion under the right conditions. And the Sun is not a giant fire. Its energy comes from nuclear fusion, a completely different process. Scientists continue to study exoplanet atmospheres and other worlds for unusual chemistry, possible habitability, and signs of processes that could resemble those found on Earth.

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Earth Is the Solar System’s Only Known Place With Ordinary Fire — TVHON