Methodology

Q: What ayanamsa does StarMeet use by default?

StarMeet uses Raman ayanamsa (22.364° at J2000.0) as the default. Users can switch to Lahiri (23.853°), True Chitrapaksha (23.906°), Krishnamurti (23.764°), or Fagan-Bradley (24.736°) in calculator settings.

Q: What is the difference between Raman and Lahiri ayanamsa?

Raman ayanamsa (22.364° at J2000) was developed by astrologer B.V. Raman and is approximately 1.5° less than Lahiri (23.853°). Lahiri is the Indian national standard adopted in 1955. The difference shifts borderline planets between signs; both systems are valid.

Q: How does StarMeet calculate planetary positions?

StarMeet uses the astronomy-engine MIT library for Julian Day conversion and tropical planetary longitudes, then subtracts the selected ayanamsa to get sidereal positions. Skyfield handles trans-Saturnian planets (Uranus, Neptune, Pluto).

Q: What divisional charts (Vargas) does StarMeet compute?

StarMeet computes 16 divisional charts: D1 (Rashi), D2 (Hora), D3 (Drekkana), D4 (Chaturthamsha), D7 (Saptamsha), D9 (Navamsha), D10 (Dashamsha), D12 (Dvadashamsha), D16 (Shodashamsha), D20 (Vimshamsha), D24 (Chaturvimshamsha), D27 (Bhamsha), D30 (Trimshamsha), D40 (Khavedamsha), D45 (Akshavedamsha), D60 (Shashtiamsha).

Q: Which Dasha systems are supported?

StarMeet supports Vimshottari Dasha (120-year cycle based on Moon nakshatra at birth) and Chara Dasha (Jaimini system based on sign-level timing). Vimshottari is the most widely used system in classical Jyotish.

How StarMeet calculates Vedic birth charts — ayanamsa, libraries, sources, and pipeline

Ayanamsa Systems

Ayanamsa is the angular correction that converts tropical planetary longitude to sidereal (Vedic) longitude — accounting for the precession of the equinoxes (~50.3″ per year). StarMeet supports five systems:

System	DMS	Decimal	Notes
Raman ★ default	22°21′48″	22.364°	Developed by B.V. Raman; preferred by many classical practitioners
Lahiri	23°51′11″	23.853°	Indian government standard (Calendar Reform Committee, 1955)
True Chitrapaksha	23°54′23″	23.906°	Based on Spica (Chitra star) at exactly 180° sidereal longitude
Krishnamurti (KP)	23°45′52″	23.764°	Used in KP system; slightly different from Lahiri
Fagan-Bradley	24°44′09″	24.736°	Western sidereal system; reference for cross-system verification

All five systems produce valid results. Consistency within a single system matters more than which system you choose. A difference of ~1.5° between Raman and Lahiri can shift borderline planets.

Calculation Libraries (MIT stack)

StarMeet runs exclusively on MIT-licensed open-source libraries — no GPL software (Swiss Ephemeris), no proprietary dependencies.

jyotishganit MIT

Core Vedic calculation engine. Computes the 9 classical planets, all 16 divisional charts (D1–D60), Vimshottari and Chara Dasha periods, nakshatra padas, and Whole Sign house assignments.

Used for: Planetary positions, Vargas, Dasha, nakshatra assignment

astronomy-engine MIT

High-precision astronomical engine for Julian Day Number (JDN) conversion, tropical longitude computation, ayanamsa values, and planetary rise/set times.

Used for: Julian Day, tropical→sidereal conversion, ayanamsa computation

Skyfield MIT

Professional-grade Python astronomy library using NASA/JPL ephemeris. Used specifically for trans-Saturnian planets where jyotishganit coverage is limited.

Used for: Uranus, Neptune, Pluto positions

Computation Pipeline

A single chart request triggers an 11-stage pipeline:

Step 1: Julian Day computation — convert birth date/time/timezone to JD (astronomy-engine)
Step 2: Ayanamsa value — retrieve sidereal offset for the selected system at the given JD
Step 3: Tropical longitudes — compute all 12 body positions (Sun through Ketu + outer planets)
Step 4: Sidereal conversion — subtract ayanamsa from tropical longitude → sidereal positions
Step 5: Lagna calculation — determine Ascendant sign from location and birth time
Step 6: House assignment — assign all planets to houses (Whole Sign system)
Step 7: Nakshatra computation — map each longitude to 1 of 27 nakshatras + pada (quarter)
Step 8: Varga charts — compute 16 divisional charts from D1 through D60
Step 9: Dasha periods — calculate Vimshottari starting balance from Moon nakshatra
Step 10: Special conditions — detect Vargottama, Gandanta, Combustion, Retrograde, Digbala
Step 11: Real-time transits — compute current planetary positions over natal chart

Special Planetary Conditions

Vargottama

A planet occupying the same sign in both D1 (Rashi) and D9 (Navamsha). Classical texts consider this a significant strengthening — the planet expresses its qualities more purely across both life-level and soul-level charts.

Gandanta

A planet within 3°20′ of the junction between water and fire signs (Cancer/Leo, Scorpio/Sagittarius, Pisces/Aries). A sensitive degree zone associated with karmic intensity and transformation.

Combustion (Asta)

A planet within close orb to the Sun. Combustion weakens the planet's significations. We use consistent orbs (Moon <12°, Mars/Saturn <15°, Mercury <14°, Jupiter <11°, Venus <10°) following BPHS guidelines.

Retrograde (Vakra)

A planet in apparent backward motion from Earth's perspective. Classical Jyotish interprets retrogrades as a planet with heightened internal or intensified expression — particularly for Saturn and Mars.

Digbala

Directional strength: Jupiter and Mercury gain Digbala in the 1st house, Moon and Venus in the 4th, Saturn in the 7th, Sun and Mars in the 10th. A planet with Digbala is especially effective for that house direction's significations.

Classical Textual Sources

Brihat Parashara Hora Shastra (BPHS)

The foundational Jyotish text attributed to Maharishi Parashara. Primary reference for house lord significations, divisional chart rules (Vargas), Vimshottari Dasha, planetary yogas, and Ashtakuta compatibility scoring.

K.N. Rao — Classical Jyotish Texts

Works by K.N. Rao (Kendriya Vidyalaya), including analyses of Chara Dasha, Navamsha interpretation, and divisional chart usage. One of the most rigorous modern scholars of classical Jyotish methodology.

Jaimini Sutras

Source for Chara Dasha (sign-based timing system), Karakamsha (soul indicator), and Jaimini-specific aspects. Used alongside Vimshottari Dasha as a complementary timing system.

Muhurta Chintamani & Hora Sara

Classical references for Panchang elements — Tithi calculation, Nakshatra quality assessment, Yoga (Sun+Moon longitude sum), Karana, and auspicious Muhurta identification.

Frequently Asked Questions

What ayanamsa does StarMeet use by default?

StarMeet uses Raman ayanamsa (22.364° at J2000.0) as the default. Users can switch to Lahiri (23.853°), True Chitrapaksha (23.906°), Krishnamurti (23.764°), or Fagan-Bradley (24.736°) in calculator settings.

What is the difference between Raman and Lahiri ayanamsa?

Raman ayanamsa (22.364° at J2000) was developed by astrologer B.V. Raman and is approximately 1.5° less than Lahiri (23.853°). Lahiri is the Indian national standard adopted in 1955. The difference shifts borderline planets between signs; both systems are valid.

How does StarMeet calculate planetary positions?

StarMeet uses the astronomy-engine MIT library for Julian Day conversion and tropical planetary longitudes, then subtracts the selected ayanamsa to get sidereal positions. Skyfield handles trans-Saturnian planets (Uranus, Neptune, Pluto).

What divisional charts (Vargas) does StarMeet compute?

StarMeet computes 16 divisional charts: D1 (Rashi), D2 (Hora), D3 (Drekkana), D4 (Chaturthamsha), D7 (Saptamsha), D9 (Navamsha), D10 (Dashamsha), D12 (Dvadashamsha), D16 (Shodashamsha), D20 (Vimshamsha), D24 (Chaturvimshamsha), D27 (Bhamsha), D30 (Trimshamsha), D40 (Khavedamsha), D45 (Akshavedamsha), D60 (Shashtiamsha).

Which Dasha systems are supported?

StarMeet supports Vimshottari Dasha (120-year cycle based on Moon nakshatra at birth) and Chara Dasha (Jaimini system based on sign-level timing). Vimshottari is the most widely used system in classical Jyotish.

Verification

Our results are cross-verified against DrikPanchang.com (Panchang values), Astro-Seek.com (planetary positions), traditional printed panchangas, and an internal test suite with 688+ unit tests covering all 40 Panchang techniques.

Minor differences (<1′) may occur between systems due to different ayanamsa values or rounding conventions. These are expected and not calculation errors.

StarMeet calculations are for educational and self-reflection purposes. Vedic astrology does not constitute medical, financial, psychological, or legal advice. See our About page for more information.