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Physics

Thermal Emission

Quick fact

The Sun's surface temperature of about 5500°C makes its thermal emission peak in visible light, while a human body at 37°C emits mostly infrared radiation, invisible to our eyes.

Why this is interesting

You've seen a hot stove glow red and felt warmth from a campfire, but did you know that even cold objects like ice emit radiation? Why does this happen, and what determines the color and amount of the emitted energy?