apparent orbit
121Timekeeping on Mars — Various schemes have been used or proposed to keep track of time and date on the planet Mars independently of Earth time and calendars. Mars has an axial tilt and a rotation period similar to those of Earth. Thus it experiences seasons of spring …
122Kepler problem in general relativity — The Kepler problem in general relativity involves solving for the motion of two spherical bodies interacting with one another by gravitation, as described by the theory of general relativity.Typically, and in this article, one body is assumed to… …
123galaxy — /gal euhk see/, n., pl. galaxies. 1. Astron. a. a large system of stars held together by mutual gravitation and isolated from similar systems by vast regions of space. b. (usually cap.) See Milky Way. 2. any large and brilliant or impressive… …
124Calendar of 2003 — ▪ 2004 January So long as there is a single Brazilian brother or sister going hungry, we have ample reason to be ashamed of ourselves. Lula, in his inaugural address as president of Brazil, January 1 January 1 The Socialist Lula (Luiz… …
1253753 Cruithne — Discovery Discovered by Duncan Waldron Discovery date October 10, 1986 …
126Rings of Saturn — The full set of main rings, imaged as Saturn eclipsed the Sun from the vantage of the Cassini spacecraft on 15 September 2006 (brightness is exaggerated). The pale blue dot at the 10 o clock position, outside the main rings and just inside the G… …
127Eris (dwarf planet) — Eris   Eris (centre) and Dysnomia (left of centre). Hubble Space Telescope …
128Pluto — /plooh toh/, n. 1. Class. Myth. a name given to Hades, under which he is identified by the Romans with Orcus. 2. Astron. the planet ninth in order from the sun, having an equatorial diameter of about 2100 miles (3300 km), a mean distance from the …
