13. Why do some stars look white while others look red?
Stars look white when all colours of the visible light are given out by a star, since white light is made up of all the coulour of the rainbow. These stars have a temperature of about 5,000 degrees centigrade at their surface. Stars look red when most of the light coming from the star is red in colour. Surface of such a star would be cooler, about 2,000 degrees centigrade.