Is lightning hotter than the Sun?

Yes, briefly. A lightning channel heats the air to about 50,000°F (around 27,700°C), roughly five times hotter than the visible surface of the Sun. The heat lasts only a split second, and the air's violent expansion is the thunder you hear.

What's actually true

A lightning bolt is about five times hotter than the Sun's surface. As a lightning channel forms, it heats the air around it to roughly 50,000°F (about 27,700°C) in a split second. The visible surface of the Sun is only about a fifth of that. The sudden heat makes the air expand violently, and that shock wave is the thunder you hear.

Takeaway: Thunder is the sound of air heated hotter than the Sun's surface in an instant.

Why people believe it

It sounds impossible because we compare the wrong things. The Sun is enormous and shines for billions of years, while a bolt is a thin channel that exists for a fraction of a second, so it feels like it should be weaker. Temperature is not the same as total energy, though. A tiny amount of air can get extremely hot without holding much energy overall. The comparison is also with the Sun's surface, not its much hotter core.

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