Knowing the mass of a star helps us understand not only the life of a star, but the evolution of galaxies. The best way to weigh a star is to measure how strongly it pulls on another star. An old star with the Sun's mass has a higher temperature than a young solar mass star. The surface gravity of a planet or star depends upon its mass and its diameter. The rate at which these granules rise and fall is determined by the star's surface gravity.

Source: Forbes December 24, 2017 19:52 UTC