Sidereal vs. Tropical Astrology: What is the Difference?

People new to astrology are often confounded by the two main schools of thought within it: tropical and sidereal. This brief lecture covers the development of the zodiac by the Babylonians and the introduction of tropical astrology by the Greek astronomers Hipparchus of Rhodes and Claudius Ptolemy. During Ptolemy’s time, the signs and constellations were closely aligned; but due to the precession of the earth’s spin axis, they have slowly separated at a rate of one degree every 71.6 years. The current divide between sidereal and tropical zodiac reckoning is 25 degrees. In three and a half centuries, that separation it will be 30 degrees, an entire sign. This raises the question: do trait characteristics come from the stars, as astrology was originally practiced, or from the tropical signs later introduced by the Greeks? The lecture covers the mechanism of precession that separates tropical from sidereal reckoning, the discovery of the ecliptic, the centerline or backbone of the zodiac, and the reemergence of sidereal astrology in the West.

[@robertcorre3010]

.A very clear and carefully done discussion on the astronomical foundations that differentiate Sidereal vs. Tropical Astrology. An excellent orientation for those not only new to astrology but also a refresher for those long immersed in this perennial tradition ... Nicely done. Thank you.

[@MasekoConverse]

Excellent elucidation

[@Kiguru100]

Thanks for the information

[@KathleenEsse]

Brilliant presentation. Highly recommended! I am a convert and have been since first reading your excellent book “An Introduction to Western Sidereal Astrology” several years ago, after 15 years as a tropicalist. Your recent workbook was incredibly insightful and I look forward to your next book with great eagerness.

[@blossomwithlotus]

Excellent video!! :) Thank you!!

[@pinkyshushu]

Crystal clear and superbly informative as always Ken, I know I will refer back to this again and again. I will also recommend anyone confused by the differences between the two approaches. The historical,context is invaluable.

[@CurtisTaylor3813]

2 words that no one else seems to innerstand when comes to tropical and those 2 words are: Latitude and Direction I'll end it there!

[@161157gor]

Very Convincing Explaination. Does Ophiuchus fit in between Scorpius & Sagittarius or is this Superfluous ? Is it diplomatic to circumvent the issue by including adjacent adjacent zodiac signs as a hybrid embracing characteristics of both...

[@kennethbowser6783]

I don't consider Ophiuchus as a sign because almost all of it is very far north of the ecliptic, that is to say, far outside the bounds of the zodiac The southernmost part of it does graze the ecliptic but covers almost entirely the same territory as Scorpio in right ascension. The argument has sometimes been advanced that most of Scorpio is south of the ecliptic, which the proponents of Ophiuchus contend contravenes the north-south argument; but most of Scorpio is much closer to the ecliptic - though south of it - than Ophiuchus, which is radically north of it. Scorpio has the brighter stars as well, among the stars nearest the ecliptic, which easily trumps Ophiuchus . One of the stars in Ophiuchus (the theta star in Ophiuchus, called Garafsa rendered as 26° Scorpio 40' in terms of SZ reckoning) was part of the Babylonian pantheon because it's close to the ecliptic with only 1° S 50' 38" of south celestial latitude, but it was not accorded sign status. When the Babylonians were laying out the zodiac toward the end of the 2nd millennium BCE, constellations that were more equatorial than elliptical were dropped as astronomical/astrological emphasis shifted from the equator to the ecliptic, which, until the Babylonians, nobody had really mapped out or worked out.