What controls the color of a star?

Answer 1

The color of a star depends on its surface temperature. But hot stars are blue, and medium-hot stars are white, and cool stars are red.

Answer 2

The color of a star is determined by its surface temperature. Hotter stars emit more blue light, while cooler stars emit more red light. This relationship is described by Wien's Law, where the peak wavelength of light emitted by a star is inversely proportional to its temperature.