Everything warm glows. Heat an object and its Planck spectrum shifts to shorter, bluer wavelengths — which is why stars run from red to blue-white.
Blackbody RadiationLive
Planck's law · Wien's displacement
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Every warm object glows with a Planck spectrum. Heat it up and the peak shifts to shorter (bluer) wavelengths — that's why stars range from red to blue-white.
Reading this result: At 5778 K the Planck curve peaks at 502 nm, inside the visible band — Wien's law makes peak wavelength ∝ 1/T, so doubling the temperature halves the peak wavelength and shifts the glow toward blue.
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How it works
The Planck radiation law gives the intensity a blackbody emits at each wavelength for a given temperature, and Wien's displacement law fixes the peak. This tool plots the curve live against the visible spectrum — the physics that launched quantum mechanics.
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The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.