Albedo used in astronomy are the (V-band) geometric albedo (measuring brightness when illumination comes from directly behind the observer) and the Bond albedo (measuring total proportion of electromagnetic energy reflected). Their values can differ significantly, which is a common source of confusion. In detailed studies, the directional reflectance properties of astronomical bodies are often expressed in terms of the five Hapke parameters which semi-empirically describe the variation of albedo with phase angle, including a characterization of the opposition effect of regolith surfaces. The correlation between astronomical (geometric) albedo, absolute magnitude and diameter is: formula_7, where formula_8 is the astronomical albedo, formula_9
Albedo One by Tachyon Productions and was in an A5 size format. From issue 13, 1996, the magazine moved to a larger A4 format and was published by Albedo One Productions. The move to new publisher and format was motivated, according to the editors, "in an effort to gain better distribution, more advertising and put a little jizz into the magazine.". "Albedo One" currently publishes original (i.e. previously unpublished) stories from Irish, European and International authors. Its focus on Irish authors has often been noted by reviewers, but publication of non-Irish authors is not excluded as with some national genre magazines, and