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The flux-weighted gravity-luminosity relationship (FGLR) is a method of determining distances to galaxies out to ~10 Mpc through observational characteristics of the brightest stars of a galaxy. It is a relation regarding the brightest supergiants, between their luminosity, radius, surface gravity and effective temperature. The brightest supergiants are early stars; they are especially blue and bright at the beginning of their supergiant phase, at which time they show a consistency encapsulated by this relation. As standard candles, they have the advantage of being the stars visible over the longest distances. The star's surface gravity and radius are estimated based upon spectral signatures (such as the Balmer jump) along with stellar structure models. The method is calibrated through observation of galactic and Local Group early stars.