As I wrote in a previous The Universe column, “The Colors of Stars, Explained,” only the brightest stars give off enough light to activate our eyes’ cones, the color-sensitive cells in the retinas. But even then, the brightest stars always appear blue, red, yellow or sometimes white. In telescopic images, even fainter stars show colors. And although astronomical photographs can be a bit tricky to interpret, the star colors in them are usually pretty representative.