# Sun, Moon and Earth

2 1.414214 ... 3 1.732051 ... One foot one degree of arc along the equator 365,242 Megalithic yard 2.72 feet 0.003 feet. Earths equatorial radius 3963.4 miles Polar radius 3950.0 miles Lunar orbit inclination to EarthSun plane 5o 8 30 9 period 173.3 days Solar angular diameter mean 0o 32 Lunar angular diameter mean 0o 31 30 Lunation Period Time between consecutive new Moons or full Moons. Ecliptic The Suns apparent path through the zodiacal belt of stars, seen from Earth. Solar Tropical Year Time between consecutive sping equinoxes. Precessional Great year Time for the zodiac to rotate backwards around the calendar. Syzygy Sun, Moon Earth in a line. e 2.718282 ... pi 3.141593 ... Sidereal lunar month 27.322 days Sunspot cycle 11 years Sidereal day 23 hours 56 minutes and four seconds Solar tropical day clock time 24 hours Lunar day average 24 hours, 52 minutes and 4.31 seconds Precessional cycle approx 25,770 years Tidal spacing average 12 hours, 26 minutes and 2.15 seconds Lunar radius 1,080 miles Lunar distance 222,000 253,000 miles mean 240,000 miles Suns radius 432,000 miles Suns distance mean 93,009,000 miles Earths axial tilt 23o 27 Earth to Moon density ratio 1.6 1 Earth to Moon mass ratio 811 Eccentricity of lunar orbit 118 IrraTIONalS SolarLunar Day Time between consecutive south transits of the SunMoon. Lunar Year 12 lunations. Sidereal Lunar Period Time for the Moon to return to the same longitude or Star. Lunar Nodes Two opposite points where the Moons path crosses the ecliptic. Eclipse Year Time between consecutive conjunctions of the Sun and north Node. phi 1.618034 ... 5 2.236068 ... aNglES raTIOS lENgThS TImES SOmE dEfINITIONS Solar Year 365.242199 days Lunar Year 354.367 days Lunation period 29.53059 days Eclipse Year 346.62 days Lunation rate 12.36826623year Saros eclipse cycle 18.03 years or 223 lunations or 6585.322 days Lunar node cycle Draconic year 18.618 years or 6800.0 days Metonic cycle 19 years or 235 lunations or 6939.602 days