What are cepheid variable stars and why are they important?

1 Answer
Nov 22, 2015

A Cepheid variable is a star that pulsates radially, and varies in temperature and diameter to produce changes in brightness.


They are important because they can be used to calculate the mass of the star if you know its mass. This can then be used to calculate the apparent magnitude of the star, and, knowing how bright the star should be according to its mass, you can then figure out how far away the star is, and this can then tell you the size of the galaxy that the star is in.