Unformatted text preview: day-night-12hours e.g. March 21 (Vernal) Sun is moving from South Cel. To North Cel. Hemisphere. Moon Synodic vs Sidereal Period 1 orbit = 27.3 days to orbit the Earth = Sidereal Period 1 Synodic Period = 29.5 days o time for MOON to complete cycle of phases o time for moon to reach same point relative to sun on celestial sphere Earth shows complementary phases to the moon’s if seen from Moon Planets Not fixed like stars Inferior planets: Mercury Venus Superior planets: Mars, Jupiter, Saturn, Uranus, Pluto, Neptune Larger orbit slower motion and longer its year Elongation- angle between planet and sun on sky for inferior planets, elongation < 90 degrees (Mercury, Venus, elongation <28 degrees) Opposition : elongation of 180 degrees only superiors...
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- Spring '07
- Solar System, Planet, Ecliptic