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 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 "Albedo One" currently publishes original (i.e. previously unpublished) stories from Irish, European and International authors.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