The colors of the stars were different, it was not drawn by anyone but indeed the colors of the stars were colorful.
Why are their colors different?In fact, the difference of colors shows that their surface temperature is very different.
The color of a star is determined by its surface temperature.
The Sun is white, in fact it is made up of colors: red, orange, yellow, green, blue, indigo, purple. The higher the temperature of a star, the more blue light is emitted by its component, so the star is blue in color. If the star's temperature is low, there is a lot of red light in the light component, so the star will be red.
Therefore the color of a star is determined by its surface temperature . Different colors represent different surface temperatures. Here is the general correspondence between color and surface temperature:
Star color and surface temperature (° C)
Thus we can base on the color of the star to predict its surface temperature.
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