Technique eligibilityDisagreement preservedParallel unvalidated models

Nakṣatra and lunar-mansion eligibility

Why Maha treats Lahiri nakṣatra placement as a sidereal technique input rather than retrofitting it onto an unlabeled tropical Moon.

Frame comparison · released 2026-08-18

Shared fact substrate

The Moon’s instant, apparent longitude, speed, and angular separation from the Sun are shared celestial facts before mansion labels are applied.

Required shared inputs

  • Moon tropical longitude
  • Named ayanāṁśa
  • Sidereal Moon longitude
  • 27-fold mansion segmentation
  • Boundary-distance tolerance

Tropical view

A tropical chart can retain Moon longitude and phase without automatically receiving a Jyotiṣa nakṣatra interpretation. Tropical lunar-mansion methods require their own named convention.

Lahiri-sidereal view

The Lahiri-sidereal Moon is segmented into 27 equal nakṣatras and padas under the declared Jyotiṣa calculation contract.

Where they agree

Both views can consume the same Moon observation and numerical precision. Neither gains additional astronomical evidence from a traditional mansion name.

Where they disagree

Technique eligibility differs: a Jyotiṣa nakṣatra rule consumes the sidereal Moon, while an unrelated tropical rule cannot claim the same placement without declaring a separate system.

Preservation policy

Keep phase geometry in the fact layer and store nakṣatra, pada, ruler, boundary distance, and rule matches only in the declared sidereal technique namespace.

Prohibited synthesis

Do not combine a tropical Moon sign with a Lahiri nakṣatra as if the pair came from one unnamed classical system, unless a registered synthesis explicitly says so.

What empirical comparison requires

Treat tropical and sidereal outputs as separate candidate models. Any performance claim requires preregistered features, outcomes, horizons, baselines, model-selection policy, multiplicity control, and prospective scoring that retains misses and abstentions.

Method sources

These sources define calculation and namespace policy. They do not determine which astrology system is true.

  1. Lahiri ayanāṁśa calculations

    Maha Celestial

    Maha’s declared transformation from retained tropical longitude to a separate Lahiri-sidereal longitude.

    Boundary: Selecting Lahiri defines one sidereal convention; it does not establish that sidereal astrology is superior or empirically valid.

  2. Astrology tradition registry

    Maha Celestial

    Named, versioned rule namespaces and the separation between source provenance and empirical support.

    Boundary: A well-sourced traditional rule remains an unvalidated interpretive claim unless separately tested.

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