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 writing of genre author Gene Wolfe. These columns are often noted for their "opinionated" or controversial stance on genre matters, with that in issue 31 of "Albedo One" being described as "a deliberately provocative rant" by one reviewer. In 1996 the editors offered an open invitation, stating that "If you feel strongly about anything and want to let us and the readers know, you too can don the mightly mantle of Severian." Between 1997 and 1999 "Albedo One" was honored three times by the European Science Fiction Society, winning Awards for "Best Magazine" and "Best Publisher". Stories from the magazine