Star color & luminosity
Explore how a star’s temperature and radius change its color, peak wavelength, and luminosity.
Your experiment
How it works
Temperature strongly affects emitted power per unit area. A large, cool star can be more luminous than a small, hot star because it has more radiating surface. Wien’s law relates temperature to the wavelength of peak emission.
Read the field note ↗About this model
Stars are approximated as blackbodies. Display colors are illustrative, not calibrated spectra. Radius is shown with a compressed visual scale.
Star color & luminosity: common questions
Are blue stars hotter than red stars?
Yes. A hotter blackbody emits relatively more short-wavelength light, shifting its appearance toward blue-white.
Does a brighter-looking star emit more light?
Not necessarily. Apparent brightness also depends on distance and any intervening dust.
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