mean orbit
101Jupiter — /jooh pi teuhr/, n. 1. Also called Jove. the supreme deity of the ancient Romans: the god of the heavens and of weather. Cf. Zeus. 2. Astron. the planet fifth in order from the sun, having an equatorial diameter of 88,729 mi. (142,796 km), a mean …
102Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …
103Planets beyond Neptune — Planet X redirects here. For the Planet X doomsday scenario, see Nibiru collision. For other uses, see Planet X (disambiguation). Trans Neptunian planets redirects here. For dwarf planets and small bodies discovered beyond Neptune, see Trans… …
104Year — A year (from Old English gēar) is the orbital period of the Earth moving around the Sun. For an observer on Earth, this corresponds to the period it takes the Sun to complete one course throughout the zodiac along the ecliptic. In astronomy, the… …
105Orbital mechanics — A satellite orbiting the earth has a tangential velocity and an inward acceleration. Orbital mechanics or astrodynamics is the application of ballistics and celestial mechanics to the practical problems concerning the motion of rockets and other… …
106Semi-major axis — The semi major axis of an ellipse The major axis of an ellipse is its longest diameter, a line that runs through the centre and both foci, its ends being at the widest points of the shape. The semi major axis is one half of the major axis, and… …
107cosmos — /koz meuhs, mohs/, n., pl. cosmos, cosmoses for 2, 4. 1. the world or universe regarded as an orderly, harmonious system. 2. a complete, orderly, harmonious system. 3. order; harmony. 4. any composite plant of the genus Cosmos, of tropical… …
108Equation of time — The equation of time is the difference over the course of a year between time as read from a sundial and time as read from a clock, measured in an ideal situation (ie. in a location at the centre of a time zone, and which does not use daylight… …
109Eris (dwarf planet) — Eris   Eris (centre) and Dysnomia (left of centre). Hubble Space Telescope …
110comet — cometary /kom i ter ee/, cometic /keuh met ik/, cometical, adj. cometlike, adj. /kom it/, n. Astron. a celestial body moving about the sun, usually in a highly eccentric orbit, consisting of a central mass surrounded by an envelope of dust and… …
