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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Ecliptic, zodiac and history
From: Bill B
Date: 2010 Dec 11, 01:10 -0500
From: Bill B
Date: 2010 Dec 11, 01:10 -0500
I am guessing when I get an answer to my question, I'll slap myself on the forehead and utter, "Of course." But here goes. I look at star charts and planispheres with the current ecliptic--the path of the sun through the stars--neatly added. I take it for granted that if I could see the stars and the Sun simultaneously that is the relationship I would see. Easy to confirm with an almanac and spherical trig. The zodiac signs--a form of right ascension or SHA--lie along the ecliptic as opposed to the celestial equator. The zodiac etc. have been around for about 3000 years, spanning the Sumerian's lunar calendar, the Babylonians, and the sexagesimal system. The shift of the First Point of Aries to its present location on the celestial equator also appears to indicate a long history of ecliptic knowledge. My question, how the heck did they figure out the ecliptic so long ago? No pi, no trig. A viewer would have to wait half a year to see the star pattern that would have that day's Sun superimposed on it. Yes? A lunar calendar with 12 cycles a year and a leap month every three years would not be a big help. Bill B.