Combining the light from two of the world’s largest visible-light telescopes, astronomers have measured, for the first time with high accuracy, the size of a small star. The diminutive body, Proxima Centauri, lies just 4.2 light-years from Earth and is the known star nearest to our solar system. Weighing in at only 15 percent of the sun’s mass, the star is one of many faint, small stars in our galaxy.