Calculationdraftschool: jyotisha· Frawley — Astrology of the Seers

Ayanamsha (the sidereal–tropical correction)

अयनांशayanāṁśa

also: ayanamsa, ayanamsha-correction

cal-ayanamsha

Definition

From Sanskrit "ayana" (solstice) + "amsha" (portion): the angular difference from the current vernal-equinox point among the fixed stars to the beginning of the (sidereal) constellation Aries. Subtracting the ayanamsha from a Tropical chart's positions yields the Sidereal (Vedic) positions. The exact value and the epoch of zero-coincidence are disputed (the Vedic star Revati that 'marks' 0° Aries is of uncertain stellar identity — see nak-revati patch).

Modern

Prāṇa relevance

Prāṇa relation not yet traced — a complete, acceptable terminal state.

Connections (1)

prerequisite-of · 1

→How to calculate the Vedic chart (from a Western Tropical chart)Modern
To produce a Vedic (sidereal) chart one computes the Western Tropical chart and then SUBTRACTS the appropriate Ayanamsha from all planetary and sign positions (Vedic position = Tropical position - Ayanamsha). A chosen Ayanamsha value is therefore a strict prerequisite of the chart calculation: the cal-vedic-chart-calculation procedure explicitly lists 'a chosen Ayanamsha (cal-ayanamsha)' among its prerequisites and cannot run without it.

Sources

txt-frawley-astrology-seersAyanamsha (book pp.51–53)Modern✓ verifieddefinition ayana+amsha; the 1950 value table & rate table; the 1900–1990 Lahiri/Yukteswar table; Revati-marks-0°-Aries dispute; Frawley prefers Sri Yukteswar's

Other attributes

Formula: Vedic (sidereal) position = Tropical position − Ayanamsha. Rate ≈ precession rate ≈ 50″/yr (varies slightly; ~9′ per 10 years → add ~0.9′/yr for intermediate years).
Divisor: n/a (an angular offset, not a modular remainder)
Remainder Interpretation: the offset shifts every sign/planet position back by the ayanamsha amount; e.g. a Tropical-Taurus Sun may become Vedic-Aries
School Variants: AYANAMSHA FOR 1950 (book p.52, verified visually p052.png): • 23°10′ — Lahiri (Govt. of India; now standard but not universally accepted) • 21°42′ — B.V. Raman • 21°46′ — Sri Yukteswar • 22°03′ — J.N. Bhasin • 24°02′ — Fagan–Bradley (American/Western Sidereal Astrology) Most Vedic astrologers: 21°40′–23°10′ for that era; Western Sidereal ≈ 24°02′. (A claimed >30° "equinox already in Aquarius" ayanamsha Frawley calls hard to validate, the equinox being still in early Pisces.) RATE OF MOVEMENT (″/yr): 48″ Lahiri · 50.3″ Raman · 54″ Sri Yukteswar. EPOCH OF COINCIDENCE: Vedic astrologers 200–550 A.D. (Sri Yukteswar: 499 A.D., 24,000-yr cycle); some Westerners use the birth of Christ. Astronomy: 25,800-yr cycle, rate ~50.3″, with admitted fluctuations. AYANAMSHA TABLE 1900–1990 (book p.53, Lahiri | Yukteswar): 1900: 22°27′59″ | 21°00′54″ · 1910: 22°35′51″ | 21°09′54″ 1920: 22°44′43″ | 21°18′54″ · 1930: 22°52′40″ | 21°27′54″ 1940: 23°01′21″ | 21°36′54″ · 1950: 23°09′34″ | 21°45′54″ 1960: 23°17′54″ | 21°54′54″ · 1970: 23°26′21″ | 22°03′54″ 1980: 23°34′31″ | 22°12′54″ · 1990: 23°42′56″ | 22°21′54″
Preferred By Frawley: Sri Yukteswar's system (guru of Paramahansa Yogananda, The Holy Science) — both astrologer and Self-realized soul; cycle begins 499 A.D., 24,000-yr, per the four-yuga theory. B.V. Raman's and J.N. Bhasin's are close.
Notes: ATTRIBUTE-HARVEST: all competing values/rates/epochs held inside this one entity (not exploded into per-system records). Numeric tables verified visually p052.png (1950 + rate) and p053.png (1900–1990) — see the rul-yuga note for p053. The unsettled value/epoch is surfaced as a question.

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