Albedo formula_5 (also called blue-sky albedo) can then be given as: Directional-hemispherical reflectance is sometimes referred to as black-sky albedo and bi-hemispherical reflectance as white-sky albedo. These terms are important because they allow the albedo to be calculated for any given illumination conditions from a knowledge of the intrinsic properties of the surface. The albedos of planets, satellites and minor planets such as asteroids can be used to infer much about their properties. The study of albedos, their dependence on wavelength, lighting angle ("phase angle"), and variation in time comprises a major part of the astronomical field of photometry. For small
Albedo One Fiction" 2006. "Albedo One" was voted 8th in the Nominations for the Hugo Award under the "Best Semiprozine" category for 2006. Although only the top five in the list are deemed to have earned a Nomination for the Hugo Award under this category, the event is notable as being the first time "Albedo One" has had a presence on the nominations list (and the first time an Irish genre magazine has had a presence). The event is also notable in that "Albedo One" was placed ahead of other well-known magazines such as "Lady Churchill's Rosebud Wristlet", "Postscripts" and "Apex Digest".