Absolute magnitude

Absolute magnitude is the measure of intrinsic brightness of a celestial object. It is the hypothetical apparent magnitude of an object at a standard distance of exactly 10 parsecs (32.6 light years) from the observer, assuming no astronomical extinction of starlight. This places the objects on a common basis and allows the true energy output of astronomical objects to be compared without the distortion introduced by distance. As with all astronomical magnitudes, the absolute magnitude can be specified for different wavelength intervals; for stars the most commonly quoted absolute magnitude is the absolute visual magnitude, which uses only the visual (V) band of the spectrum (UBV system). Also commonly used is the absolute bolometric magnitude, which is the total luminosity expressed in magnitude units that takes into account energy radiated at all wavelengths, whether visible or not.

Absolute Magnitude (magazine)

Absolute Magnitude is a discontinued, semi-professional science fiction magazine started in 1993 under the name Harsh Mistress. However, in 1994 after only two issues the name was changed to Absolute Magnitude. In 2002 the name was changed again to Absolute Magnitude & Aboriginal Science Fiction when the publishers acquired the rights to Aboriginal Science Fiction. Absolute Magnitude was published by DNA Publications and edited by Warren Lapine. Although it was supposed to be a quarterly magazine its actual releases were irregular. After releasing twenty-one issues under the Absolute Magnitude title (plus two as Harsh Mistress), the magazine ceased publication in March 2006.

Absolute Magnitude was nominated for the 2002 Hugo Award for Best Semiprozine with Lapine noted as the editor.

Anthology

Absolute Magnitude is also a collection of sixteen stories taken from the magazine between 1993 and 1997. The anthology was published by Tor Books and was released on April 15, 1997. It has been issued in both hardcover and paperback editions.