How Do Scientists ‘Weigh’ Stars?
Stars are enormous balls of hot gas located many trillions of miles away, but when they’re observed from the Earth, they appear as tiny shining dots visible in the night sky. In a new study, astronomers made a precise measurement of the mass of a nearby “white dwarf,” a star that has reached the end of its life cycle.
Such estimates can be done with stars as well. Sensitive instruments, such as NASA’s Kepler space telescope, can detect planets orbiting stars on the other side of the Milky Way by measuring tiny changes in the velocity of the stars as the planets “tug” on them in their orbits, Oswalt explained. These measurements can also provide researchers with information about the stars’ masses.