Albedo distribution of solar radiation reaching the Earth's surface. These factors vary with atmospheric composition, geographic location and time (see position of the Sun). While bi-hemispherical reflectance is calculated for a single angle of incidence (i.e., for a given position of the Sun), albedo is the directional integration of reflectance over all solar angles in a given period. The temporal resolution may range from seconds (as obtained from flux measurements) to daily, monthly, or annual averages. Unless given for a specific wavelength (spectral albedo), albedo refers to the entire spectrum of solar radiation. Due to measurement constraints, it is often given
Surface-to-surface missile bomb was the first operational surface-to-surface missile. Contemporary surface-to-surface missiles are usually guided. An unguided surface-to-surface missile is usually referred to as a rocket (for example, an RPG-7 or M72 LAW is an anti-tank rocket whereas a BGM-71 TOW or AT-2 Swatter is an anti-tank guided missile). Examples of surface-to-surface missile include the MGM-140 ATACMS, the Ground-Launched Small Diameter Bomb (GLSDB) and the Long Range Precision Fires (LRPF). Surface-to-surface missiles are usually broken down into a number of categories: Different parties break down missile type by the range differently. For example, the United States Department of Defense has no definition