A type of Cassegrain telescope in which the primary mirror is a hyperboloid. It is designed to eliminate coma and spherical aberration, thus providing a relatively large field of view as compared to a
more conventional configuration.
A river is a natural waterway that transits water through a landscape from higher to lower elevations called divides. The divide determines which way a river will flow. It is an integral component of
the water cycle. The water within a river is generally collected from precipitation through surface runoff, groundwater recharge (as seen at baseflow conditions / during periods of lack of precipitation) and release of stored water in natural reservoirs, such as a glacier