Astrology is a language; the branches are its dialects.

There are many, many branches and disciplines of astrology. Just to name a few:

Progressions/Solar Arc Directions


Relationship; Composite and Synastry


The Origins of Western (Tropical) Astrology

Topical or Western Astrology is born out of the traditions of the Babylonian period (2000 – 1600 BCE) and from Egypt. It even goes further back in time into ancient Mesopotamia around 4000 years ago1. We don’t know for certain when or how these traditions merged due to the lack of surviving sources or their full clarity, but we can surmise that sometime in the 1st century BCE, Egyptian and Babylonian astrology came together, and then a new framework of Hellenistic (or Greek) astrology emerged more distinctly from the 3rd century BCE through the 7th century CE.

Western astrology’s trajectory has continued through its evolutionary periods of branching, diminishing, and flourishing (not all in that order) until now. Notably, the 5th century BCE saw the significant branching of astrology and mathematical astronomy; up until this time, the two basically coexisted together. Further notable points of change occurred with the Renaissance period, the invention of the telescope, and the discovery of the outer planets of our solar system. More recently, the use of computers to calculate and generate charts, and now the widely accessible use of online applications and websites, allow astrological information at nearly anyone’s fingertips. The discoveries and pioneering continues today.

1Brennan, Chris. “Chapter 2: The Origins of Hellenstic Astrology.” Hellenistic Astrology: The Study of Fate and Fortune, Amor Fati Publications, Denver (Colorado), 2020.

Tropical or Sidereal Astrology?

The main difference between Tropical (or Western) and Sidereal (often known as Vedic) Astrology systems is where the 12 signs of the zodiac are referring to.

Sidereal or Vedic systems of astrology look at where the planets are moving through the actual constellations of the 12-sign zodiac;

Tropical Astrology links the zodiac sign to the seasons — the movement of the Sun at the solstices and equinoxes through the year.

In this fashion, in the northern hemisphere, the Spring (Vernal) Equinox is the moment where the length of day and night is equal in the spring season, and marks the beginning of the sign of Aries.

However, due to the earth’s wobble on its axis and the precession of the equinoxes, on that same day of the Vernal Equinox, the position of the Sun will not always be pointing towards the Aries constellation. There was a time when the positions of the Tropical and Sidereal zodiacs overlapped and aligned around 285 AD. The Vernal Equinox point moved from Aries to the Pisces constellation in the 1st century BCE, and will continue until the 26th century, at which point it will move into the Aquarius constellation.

All this is to say, some astrologers practice Vedic Astrology, and others practice Tropical Astrology. They are both valid! One is not right or better than the other.

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