Geometric albedo For Earth-bound observers this occurs when the body in question is at opposition and on the ecliptic. The visual geometric albedo refers to the geometric albedo quantity when accounting for only electromagnetic radiation in the visible spectrum. The surface materials (regoliths) of airless bodies (in fact, the majority of bodies in the Solar System) are strongly non-Lambertian and exhibit the opposition effect, which is a strong tendency to reflect light straight back to its source, rather than scattering light diffusely. The geometric albedo of these bodies can be difficult to determine because of this, as their reflectance is strongly peaked
Albedo feature Albedo feature An albedo feature is a large area on the surface of a planet (or other solar system body) which shows a contrast in brightness or darkness (albedo) with adjacent areas. Historically, albedo features were the very first (and usually only) features to be seen and named on Mars and Mercury. Early classical maps (such as those of Schiaparelli and Antoniadi) showed only albedo features, and it was not until the arrival of space probes that other surface features such as craters could be seen. On bodies other than Mars and Mercury, an albedo feature is sometimes called a