Astrophysics (Index)About

surface brightness fluctuation

(apparent indication of an elliptical galaxy's distance)

Surface brightness fluctuation (SBF) is a phenomenon evident when observing distance galaxies: given some of the averaging of apparent surface brightness due to the limits of the telescope and instrument's resolution, the further away the galaxy, the smoother the apparent surface brightness despite the random positions of the stars of varying brightness in the galaxy. The relation is imperfect, yet sufficiently consistent to give a distance estimate for elliptical galaxies (the surface brightness fluctuations method). The estimate is improved by taking other characteristics of the galaxy into account.

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