A basic observable quantity for a star is its brightness. Because
stars can have a very broad range of brightness, astronomers commonly
introduce a logarithmic scale called a
magnitude scale to classify the
brightness.
where "log" means the (base-10) logarithm of the corresponding number; that is,
the power to which 10 must be raised to give the number.
Because this relation is logarithmic, a very large range in brightnesses
corresponds to a much smaller range of magnitudes; this is a major utility of the
magnitude scale.
No comments:
Post a Comment