Today! From Earth’s Perspective: A. Celestial Coordinates B. Precession of the equinoxes

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Today! From Earth’s Perspective: A. Celestial Coordinates B. Precession of the equinoxes C. Astrology?. The Celestial Sphere (Pythagoras) FROM NOTES Celestial sphere - -imaginary sphere on which the 'fixed stars' are located - PowerPoint PPT Presentation

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Today!

From Earth’s Perspective: A. Celestial Coordinates B. Precession of the equinoxes C. Astrology?

The Celestial Sphere (Pythagoras) FROM NOTES

Celestial sphere--imaginary sphere on which the 'fixed stars' are located --gives angular position of objects in the sky, has arbitrary size, and earth turns underneath it.Zenith--point directly overhead on sphere.Local Coordinates—altitude and azimuth.Celestial poles--points just above N. and S. pole.Meridian--circle passing through poles and zenith.A great circle--divides sphere in half. A Great Circle (the meridian is an example) on the sphere has 360 degrees. 1 degree = 60 (arc)minutes = 60' 1 (arc)minute= 60 (arc)seconds = 60" Celestial equator--great circle on the sphere formed by cutting through earth's equator.The ecliptic--great circle which is sun's path --tilted 23 ½E from the celestial equator.Angular separation (distance)--no. of deg., min., sec. between objects or points on sphere. Angular size or diameter--angle an object subtends at observer'sdistance.

Local Coordinates:altitude and azimuth

Dobsonian telescope:moves in local coordinates

On the celestial sphere,stars are like cities on the sky.

Just like cities on the earth, it takes two coordinatesTo give us their location.

The two ‘Celestial Coordinates’ on the Celestial Sphere areanalogous to longitude and latitude.

Right Ascension—0-24 hours (like time zones, buton the sky). Starts at star Psi Piscium, presentposition of the Vernal Equinox, point where theSun crosses the celestial equator.Declination—0 to + or – 90 degrees (Latitude is N. and S.)

Precession of the Equinoxes--earth'saxis traces out a circle on the skyevery 25,800 years, and the point ofthe vernal equinox shifts through allthe signs of the zodiac.

Polaris will Not always beThe North Celestial Pole.

Earth’s axis points toward 12 signs in succession.Also the sun, seen from earth, moves around in 1 year.

Zodiac--the circular band of 12 constellations thesun passes in front of, one cycle in a year. Called the'circle of animals'--the 12 astrological signs.

Claudius Ptolemywrote a book called Tetrabibliosaround 150 AD.This codified Western Astrology.

However, the Precession of the Equinoxes has changed the position of the sun in the zodiac by about two thirds of a sign since Ptolemy.Those born between about the 22nd of each month Through the 10th of the nextActually had the previous sign at birth.

In the 1970’s,Michel Guaquelin, a psychologistWith an open mind,studied 60,000 birth chartsWith an open mindand scientific statistics.

He found no evidence for: Sun signs Houses Aspects

But he did find evidence that:Mars and other planetsbeing at power points (just above the horizon, or just below —and at right angles–at birth)relate to success in sports and other occupations.

It does also seem that planets in these positionsimpart the planetary influences indicatedby astrologers.