unstable orbit
81Moon — /moohn/, n. Sun Myung /sun myung/, born 1920, Korean religious leader: founder of the Unification Church. * * * Sole natural satellite of Earth, which it orbits from west to east at a mean distance of about 238,900 mi (384,400 km). It is less… …
82particle accelerator — accelerator (def. 7). [1945 50] * * * Device that accelerates a beam of fast moving, electrically charged atoms (ions) or subatomic particles. Accelerators are used to study the structure of atomic nuclei (see atom) and the nature of subatomic… …
83Earth — This article is about the planet. For other uses, see Earth (disambiguation). Earth   …
84Asteroid belt — For the album by Velvet Chain, see Asteroid Belt (album). The asteroid belt (shown in white) is located between the orbits of Mars and Jupiter. The asteroid belt is the region of the Solar System located roughly between the orbits of the planets… …
85astronomy — /euh stron euh mee/, n. the science that deals with the material universe beyond the earth s atmosphere. [1175 1225; ME astronomie ( < AF) < L astronomia < Gk. See ASTRO , NOMY] * * * I Science dealing with the origin, evolution, composition,… …
86eye, human — ▪ anatomy Introduction specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit The eye is protected from mechanical injury… …
87Dynamical system — This article is about the general aspects of dynamical systems. For technical details, see Dynamical system (definition). For the study, see Dynamical systems theory. Dynamical redirects here. For other uses, see Dynamics (disambiguation). The… …
882060 Chiron — 95P/Chiron Discovery Discovered by Charles T. Kowal Discovery date October 18, 1977 …
89Gravity assist — In orbital mechanics and aerospace engineering, a gravitational slingshot, gravity assist or swing by is the use of the relative movement and gravity of a planet or other celestial body to alter the path and speed of a spacecraft, typically in… …
90Enceladus (moon) — Infobox Planet name = Enceladus alt names = Saturn II adjectives = Enceladean caption = Degraded craters, fractures and disrupted terrain in Cassini mosaic of the north polar region of Enceladus bgcolour = #a0ffa0 discovery = yes discoverer =… …
