Download Precession Note 12 Precession – slight “wobble” in Earth`s axis of

Precession
Note 12
Precession – slight “wobble” in Earth’s axis
of rotation that traces a cone over a period
of 26,000 years
Why does Earth “wobble”?
- Earth’s rotation on axis causes equatorial
regions to slightly bulge out (like a skater’s
skirt as she spins rapidly)
- Sun & moon exert a gravitational “tug” on
bulge trying to align it with the Ecliptic
Plane
The Plane of the Ecliptic is an imaginary
“slice” of the solar system that most planets
line up with (Pluto excepted)
- This tug & rotational motion of Earth on its
axis causes Earth to wobble about its axis of
rotation
- So our North star will not always be Polaris
(in about 13,000 years, North will point to
Vega)
Zodiac and Equinoxes
- all zodiac signs lie on or near the plane of
the ecliptic
- according to astrology, a person’s sign is
determined by the position of the sun on the
date they were born
- your sign should be the constellation that
was behind the sun when you were born
- currently there are 12 signs used in
astrology but there are actually 13 that lie on
the plane of ecliptic
- Ophiucus lies
between
Scorpio and
Sagittarius
but is not used
- sign dates were set up so the Vernal
Equinox is when Aries “enters” (is behind)
the sun
- however, because of Precession, Aries is no
longer behind the sun at the Vernal Equinox
(Pisces is)
Next time you read a horoscope, think about
that!!!
If you have ever heard the song, Age of
Aquarius – It says “This is the dawn of
the age of Aquarius”
That's true. Because of Precession,
Aquarius is almost behind the sun at the
equinox