Fathoming Andromeda
Studies of Cepheids — a particular type of variable star with a known luminosity — in the Andromeda Galaxy resulted in an accurately measured distance.
Credit:NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Studies of Cepheids — a particular type of variable star with a known luminosity — in the Andromeda Galaxy resulted in an accurately measured distance.
Credit:NASA, ESA, and the Hubble Heritage Team (STScI/AURA)