Atmospheric refraction Atmospheric refraction is considered in measuring the position of both celestial and terrestrial objects. Astronomical or celestial refraction causes astronomical objects to appear higher above the horizon than they actually are. Terrestrial refraction usually causes terrestrial objects to appear higher than they actually are, although in the afternoon when the air near the ground is heated, the rays can curve upward making objects appear lower than they actually are. Refraction not only affects visible light rays, but all electromagnetic radiation, although in varying degrees. For example, in the visible spectrum, blue is more affected than red. This may cause astronomical
A-235 anti-ballistic missile system eliminates the use within the limited armed conflict and other situations of this kind; secondly, the system must be mobile, without a rigid binding to any object or center; thirdly, it must provide interception at an altitude of at least 500–750 km, that is, at Low Earth Orbit] . A-235 anti-ballistic missile system A-235 PL-19 "Nudol" () is a Russian anti-ballistic missile and anti-satellite weapon system in development. This system is designed to deflect a nuclear attack on Moscow and important industrial regions. The main developer of the system is JSC Concern VKO Almaz-Antey. The new system should replace the