Hindu Predictive Astrology Part 7: Hindu Method of Casting the Horoscope
We've spent six articles building your vocabulary. Now it's time to use it. In this article, you'll learn to cast a complete Hindu horoscope from birth data, following the traditional method used by generations of Indian astrologers.
Part 7 of 31 • Building the Horoscope • Covers: Book Chapter VIII — Hindu Method of Casting the Horoscope
The horoscope is simply a scheme or a plan representing an accurate picture of the heavens — the positions of the planets and stars for the moment at which a child is born, or at any particular moment.
The map of the heavens containing 12 divisions is drawn in either a square or circular form. Different regions of India and the world use different formats, but they all represent the same celestial reality. In this article, we walk through the complete process using Raman's own illustrated example.
Chart Formats: South Indian, North Indian & Western
Three chart formats are in common use. The key difference is what stays fixed and what moves:
FIXED
Signs stay fixed. Planets and the Ascendant are placed in the appropriate sign boxes.
Diamond/Lozenge pattern
12 triangular houses arranged in a diamond. Houses stay fixed (1st always at top). Signs rotate based on the Ascendant.
Houses stay fixed. The Ascendant sign is placed in the 1st house position (top), and remaining signs follow.
Circular wheel
12 segments in a circle. Ascendant on the left (East). Counter-clockwise sign placement.
Circular format. Used by Western astrologers. Hindu astrologers can convert Western charts by subtracting the Ayanamsa.
The Step-by-Step Process
We'll follow Raman's own illustration: a male born on 8th August 1912 at 5:35 PM (IST), at latitude 13° North, longitude 77°34' East (Bangalore).
Convert Birth Time to Ghatis
Ascertain the exact moment of birth and sunrise. If the time is in English hours, convert it into ghatis. If the birth occurred after midnight but before sunrise, it belongs to the previous day (the Hindu day runs sunrise to sunrise).
Birth time: 5:35 PM = 17h 35m
Time since sunrise: 17h 35m − 5h 35m = 12 hours
Convert: 12 × 2.5 = 30 ghatis
Birth occurred at 30 ghatis after sunrise.
Find the Moon's Nakshatra and Pada
From the almanac, find the constellation ruling on the day of birth. Calculate the total duration of the constellation, divide by 4 to get the pada duration, then determine how far the Moon has progressed.
On 8-8-1912: Rohini rules for Gh. 21-59
On 9-8-1912: Mrigasira ends at Gh. 19-15
Total duration of Mrigasira:
(60 − 21.59) + 19.15 = Gh. 38-01 + Gh. 19-15
= Gh. 57-16
Each pada: 57-16 ÷ 4 = Gh. 14-19
Time elapsed in Mrigasira at birth:
Birth time (30-00) − Rohini end (21-59)
= Gh. 8-01
Since 8-01 < 14-19 (one pada), Moon is in
Mrigasira, 1st pada → Taurus
Place All Planets from the Almanac
For each planet, find its nakshatra and pada from the almanac. Use the sign-nakshatra mapping table (from Part 4) to determine which sign each planet occupies.
| Planet | Nakshatra | Pada | → Sign |
|---|---|---|---|
| ☉ Sun | Aslesha | II | Cancer ♋ |
| ☽ Moon | Mrigasira | I | Taurus ♉ |
| ♂ Mars | Pubba | III | Leo ♌ |
| ☿ Mercury | Makha | II (℞) | Leo ♌ |
| ♃ Jupiter | Jyeshta | II | Scorpio ♏ |
| ♀ Venus | Makha | I | Leo ♌ |
| ♄ Saturn | Rohini | I | Taurus ♉ |
| ☊ Rahu | Revati | III | Pisces ♓ |
| ☋ Ketu | Chitta | I | Virgo ♍ |
Note: Mercury is marked (℞) indicating retrogression on the day of birth.
Calculate the Ascendant (Lagna)
The Ascendant is the sign rising on the eastern horizon at the moment of birth. Each sign takes a specific duration to rise, depending on the latitude. Using the oblique ascension tables (Appendix B in the book), sum the rising durations until the birth time is reached.
Cancer's rising duration at 13°N: Gh. 5-31
Degrees per vighati: 5-31 × 60 / 30 = 11⅓ vighatis per degree
Sun has gained: 23 × 11⅓ / 30 = Gh. 4-14
Cumulative sign durations from Cancer:
Cancer remaining: 5-31 − 4-14 = Gh. 1-17
Leo: Gh. 5-20⅝
Virgo: Gh. 5-06
Libra: Gh. 5-06
Scorpio: Gh. 2-20⅝
Sagittarius: Gh. 5-31
Total: Gh. 27-41⅔
Birth at Gh. 30-00. Sagittarius ends at Gh. 27-41⅔.
∴ Ascendant = Capricorn
Time elapsed in Capricorn: 30 − 27-41⅔ = Gh. 2-18⅓
Find the Exact Ascendant Degree
Convert the time elapsed in the Ascendant sign to degrees:
Time elapsed: 138⅓ vighatis
30° / 312⅔ × 138⅓ = 13° 17' Capricorn
This is the Bhavamadhya (mid-point) of the 1st house.
The 1st house extends roughly 15° on either side:
from ~29° Sagittarius to ~28° Capricorn.
The Completed Rasi Chart
Placing all planets and the Ascendant into the South Indian chart format, the horoscope of the person born on 8-8-1912 at 5:35 PM, Bangalore, looks like this:
Rahu
Moon
Saturn
Ascdt.
Born 8-8-1912
5:35 PM IST
13°N, 77°34'E
Sun
Mars
Merc.(℞)
Venus
Jupiter
Ketu
Computing Exact Planetary Longitudes
For basic chart reading, knowing the sign is sufficient. But for precise Dasa calculations, divisional charts, and advanced techniques, you need the exact degree, minute, and second of each planet. Raman demonstrates this with the Sun:
5th Aug 1912: Sun enters 3rd qtr of Aslesha at Gh. 46-30
9th Aug 1912: Sun enters 3rd qtr of Aslesha at Gh. 17-44
Time for Sun to traverse 1 pada (3°20'):
5th Aug: 60 − 46.30 = Gh. 13-30
6th Aug: Gh. 60-00
7th Aug: Gh. 60-00
8th Aug: Gh. 60-00
9th Aug: Gh. 17-44
Total: Gh. 211-14 = 12,674 vighatis
Time from pada entry to birth:
5th Aug: Gh. 13-30
6th Aug: Gh. 60-00
7th Aug: Gh. 60-00
8th Aug: Gh. 30-00 (birth moment)
Total: Gh. 163-30 = 9,810 vighatis
Sun's arc traversed:
(10/3)° × 9810/12674 = 2° 34' 48"
Sun's position in Cancer:
Padas passed: Punarvasu(1) + Pushyami(4) + Aslesha(1) = 6
= 6 × 3°20' = 20°
Add traversed arc: 20° + 2°34'48"
= 22° 34' 48" Cancer
The same procedure is applied to compute the exact longitude of every planet. Similarly, for the other planets, the longitudes must be computed in the same manner. For beginners, Raman advises confining attention to these primary rules without worrying about the full technique of mathematical astrology at first.
Practical Tips for the Modern Student
Today, VedAstro.org and other Vedic astrology calculators do all this computation instantly. But understanding the manual process is essential — it teaches you what the numbers mean and helps you spot errors in software output.
For all practical purposes, almanacs published by competent Hindu astronomers, giving the planetary positions, can be used by beginners. After acquiring familiarity, the student may refer to modern ephemerides for greater accuracy.
Key Takeaways
-
The horoscope is a map of the heavens at a specific moment
Three formats exist: South Indian (fixed signs), North Indian (fixed houses), and Western (circular). This series uses South Indian. -
Step 1: Convert birth time to ghatis after sunrise
Remember: Hindu day = sunrise to sunrise. After-midnight births belong to the previous day. -
Step 2: Find the Moon's nakshatra and pada from the almanac
Calculate total constellation duration, divide by 4 for pada duration, determine Moon's progress. -
Step 3: Place all 9 planets by their nakshatra-pada → sign mapping
Use the sign-nakshatra table from Part 4 to convert nakshatra positions to zodiacal signs. -
Step 4: Calculate the Ascendant using oblique ascension tables
Sum rising durations of signs from the Sun's position until exceeding the birth time in ghatis. -
Step 5: Compute exact degrees for precision work (Dasa calculation, divisional charts)
Use proportional calculation: time elapsed ÷ total transit time × arc in degrees.
In Part 8, we'll learn the Western method of horoscope casting and how to convert it to the Hindu system — essential for modern practitioners who use ephemerides and software that output tropical (Sayana) positions.
Based on
Hindu Predictive Astrology
by B.V. Raman | First published 1938 | UBS Publishers' Distributors Ltd.