Jyotish, or Vedic astrology, is the chief form of astrology currently practiced in India. Part of a larger culture of Hinduism, it is derived from the same source as Western astrology (although what source that is - India or Babylon - is disputed), and the two systems share most basic concepts such as the signs, planets, and houses, as well as their general interpretive meanings. Jyotish is a chief source of reference for many Hindus across India, and Vedic astrologers will frequently prescribe special stones or Hindu mantras to those facing difficult or unclear futures as predicted by means consistent with Jyotish methodology. Frequently, though not always, Brahmins are the primary practioners (and, hence, experts for referral) of Jyotish.
The term "Vedic astrology" is itself something of a misnomer, introduced by American astrologers in the 1980s and 1990s. 'Vedic' refers to the Hindu holy texts, known as Veda. However, there is very little, if anything, recognizable as astrology in these texts. A more accurate term would be 'Indian astrology' or 'Hindu astrology.' In the end, however, all of these words are English. In the ancient Indian language of Sanskrit, 'Vedic astrology' is referred to as jyotisha, which means the 'science of light.' Modern speakers of Indian languages pronounce the same word jyotish - hence the name of this article.
Jyotish dates back at least as far as the 3rd millennium BC, and is still commonly used to aid in important decisions in modern India. In Hindu culture, newborns are traditionally named based based on their jyotish charts.
Hindu and Western astrologies
The fundamental difference between the two lies the measurement of the Zodiac. Vedic astrology uses the sidereal zodiac (the stars are considered to be the fixed background against which the motion of the planets is measured), whereas most Western astrology uses the tropical zodiac (the motion of the planets is measured against the position of the Sun on the Spring equinox). The most obvious effect of this difference is that about 80% of planets in a Western chart will move to the previous sign in a Vedic reading of the same chart.
Jyotish has developed separately from Western astrology for thousands of years. Proponents of Vedic astrology claim to have evolved a uniquely rich and powerful system of interpretation and prediction incorporating truly Hindu elements not found elsewhere, such as the system of Moon signs (called nakshatras).
Fundamentals of Jyotish
Jyotish is based on what Western astrologers call the whole house system and recognizes nine grahas (heavenly bodies or "planets"):
There are two different Jyotish chart notations, which are functionally equivalent but quite different in appearance. The following images show the same birth chart in both notations.
The charts are broken into twelve sections, houses or Bhavas, each of which is related to a rashi in an equal house system.