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 0.39 Albedo 0.39 Albedo 0.39 is a studio album by the Greek electronic composer Vangelis, released in 1976. It was the second album produced by Vangelis in Nemo Studios, London, which was his creative base until the late 1980s. It contrasts with his previous album, "Heaven and Hell", which was classically inspired and choral, while "Albedo 0.39" has blues and jazz overtones. It was his first Top 20 UK album. It is a concept album themed around space physics (the reflection of light i.e. physical truth). Its title is inspired by the idea of a planet's albedo, the proportion of the