# Moira

**Ephemeris and Astrology Computation Engine**

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[![Precision: ERFA-Audited](https://img.shields.io/badge/Precision-ERFA--Audited-success.svg)](#validation-evidence)
[![Ephemeris: JPL DE4xx](https://img.shields.io/badge/Ephemeris-JPL%20DE4xx-blueviolet.svg)](https://naif.jpl.nasa.gov/naif/index.html)
[![AI Visibility: Optimized](https://img.shields.io/badge/AI--Visibility-Optimized-success.svg)](llms.txt)
[![Status: Stable](https://img.shields.io/badge/status-stable-success.svg)](#requirements-and-installation)
[![DOI](https://img.shields.io/badge/DOI-10.5281%2Fzenodo.19152528-blue.svg)](https://doi.org/10.5281/zenodo.19152528)
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Moira is an astronomy-first astrology engine built for transparent astrology calculations, reproducible chart computation, and an inspectable calculation chain from astronomical inputs to astrological outputs. It is an auditable astrology engine with explicit computational policy, deterministic behavior, and readable reduction stages grounded in modern standards and references including JPL DE441, IAU 2000A/2006, ERFA/SOFA-aligned practices, and Gaia DR3-linked star data where applicable. Performance-critical computations — nutation, SPK kernel reading, apparent planetary evaluation (via `NativePlanetaryEvaluator`), coordinate transforms, light-time iteration, harmogram analysis, and event searching — are executed by a native C++17 extension (`_moira_native`) compiled with pybind11.

## Why Moira Exists

Most astrology software surfaces results without exposing the mathematical path. Moira exists as a Swiss Ephemeris alternative for users who need visibility into assumptions, intermediates, and provenance, so astronomy remains the foundation and astrology remains the purpose.

## AI and LLM Visibility

Moira is designed to be highly discoverable and understandable by AI agents (e.g., GitHub Copilot, ChatGPT, Claude). 

- **Machine-Readable Index**: See [llms.txt](llms.txt) for a high-level summary and [llms-full.txt](llms-full.txt) for a comprehensive documentation index.
- **Agent Doctrine**: The [AGENTS.md](AGENTS.md) file defines the "Urania" persona and operational laws for AI collaboration.
- **Structured Documentation**: Canonical documentation is maintained in the `wiki/` directory with explicit validation reports.

## What Makes It Different

Moira is designed for full computational transparency: the computation pipeline is explicit and its stages are named and controllable via the Python API, computational doctrine is explicit rather than hidden in defaults, and validation is treated as first-class evidence rather than post-hoc narrative. The high-performance core (`_moira_native`) is C++17; the Python layer owns the API surface, orchestration, and per-stage controls.

## Who It Is For

Moira is for developers, researchers, and serious practitioners who want a programmable, audit-ready engine for high-integrity astrological work, reproducible pipelines, and methodical comparison against external authorities.

## What It Is Not

Moira is not primarily a UI app, not a thin wrapper over opaque compiled stacks, and not convenience-first astrology output generation without traceability.

## Quick Capabilities

Moira computes planetary and stellar positions, houses, aspects, lots, dignities, predictive techniques, a full Vedic/Jyotish suite (yogas, Shadbala, Ashtakavarga, upagrahas, avasthas, Jaimini), eclipse and occultation events, and related analytical products on top of a modern astronomical substrate (JPL kernels, IAU models, and validated star frameworks), with a native C++ computational core, Python orchestration layer, inspectable intermediate stages, and an optional FastAPI REST server (`moira_server`) exposing the engine as typed, versioned routes.

---

## What Moira Computes

### Positions and Bodies

- **Planets and luminaries** — geocentric and topocentric reduction with iterative light-time, annual aberration, multi-body relativistic deflection (Sun, Jupiter, Saturn, Earth), IAU 2006 frame bias, and WGS-84 topocentric parallax.
- **Fixed stars** — sovereign registry of 1,809 named stars with proper motion, parallax, epoch propagation, and Stellar Quality classification. Audited anchor residual against SOFA/ERFA: 0.00048 arcseconds (J1000–J3000).
- **Asteroid catalog** — unified catalog of 1,382 asteroids covering all 119 recognized asteroid families, including the classical four (Ceres, Pallas, Juno, Vesta), Centaurs (Chiron, Pholus, Chariklo, Asbolus, Hylonome), and Trans-Neptunians (Ixion, Quaoar, Varuna, Orcus). Built from JPL Horizons as 56 Type-13 SPK shards covering 1600–2500 CE at sub-milliarcsecond interpolation fidelity, discovered via manifest under any kernel search root. User-supplied `.bsp` kernels remain supported via the integrated `daf_writer` for any of the 887,000+ numbered minor planets in the JPL catalog.
- **Numbered periodic comets** — 497 comets (1P/Halley through 516P) from JPL Horizons as sharded Type-13 kernels (1600–2500 CE), with canonical numbered designations (`"1P/Halley"`) and curated short aliases accepted as inputs.
- **Uranian / Hamburg School bodies** — 8 hypothetical transneptunian planets (Cupido through Poseidon) plus Transpluto.
- **Lunar nodes and apsides** — True Node, Mean Node, Mean Lilith, True Lilith, and orbital nodes/apsides for all planetary bodies.
- **Variable stars** — phase and magnitude engine for eclipsing binaries and intrinsic variables; dedicated Algol API.
- **Multiple star systems** — Kepler orbital mechanics for visually resolvable pairs (Sirius AB, Alpha Centauri AB); catalog of 8 astrologically significant systems across VISUAL, WIDE, SPECTROSCOPIC, and OPTICAL types.

### Chart Calculation

- **House systems** — 22 systems including Placidus, Koch, Regiomontanus, Campanus, Morinus, Porphyry, Whole Sign, Equal, APC, Pullen Sinusoidal Delta/Ratio, and Sunshine. Includes branch-aware high-latitude doctrine where admitted, explicit polar fallback policy, and `house_of` for direct house placement lookups.
- **Aspects** — 22 zodiacal aspects with applying/separating/stationary motion-state detection; declination parallels and contra-parallels; antiscia and contra-antiscia; exact partile and orbed platic status markers (`is_partile`, `is_platic`).
- **Aspect patterns** — 21 multi-body configurations: T-Square, Grand Trine, Grand Cross, Yod, Kite, Mystic Rectangle, Stellium, Grand Sextile, Thor's Hammer, Boomerang Yod, and more.
- **Midpoints** — full midpoint matrix, midpoint trees, 90°/45°/22.5° dial projections, planetary pictures.
- **Traditional dignities** — domicile, exaltation, triplicity (diurnal/nocturnal), Egyptian and Ptolemaic terms, face, sect, hayz, and Almuten Figuris.
- **Arabic Parts** — 499 lots with dependency graphs and condition profiling.
- **Hermetic decans** — 36-decan system with computed positions for all ruling stars.
- **Draconic charts** — node-anchored draconic frame (mean or true node) with longitude rotation, engine-backed chart derivation, and caller-supplied position support.

### Predictive Techniques

- **Progressions** — secondary, tertiary, minor, solar arc (longitude and right ascension), Naibod, ascendant arc; direct and converse variants for all methods.
- **Primary directions** — Placidus semi-arc/mundane, Regiomontanus, and Morinus method families with mundane and zodiacal variants; direct and converse directions (converse computed by true role exchange, not arc negation); speculum computation; fixed-star targets; seven conventional time-key presets.
- **Returns** — solar and lunar returns; planet returns.
- **Time lords** — annual and monthly profections; Firdaria (diurnal and nocturnal sequences, including Bonatti variant); Zodiacal Releasing (Vettius Valens method); Hyleg and Alcocoden.

### Vedic / Jyotish Suite

Every Vedic engine is implemented from primary-source research (BPHS, Brihat Jataka, Saravali, Phaladeepika, Uttara Kalamrita, Jataka Parijata, Jaimini Upadesa Sutras, and the named 1879 Agastya- and 2024 Bogamuni-attributed Pancha Pakshi witnesses) with per-rule citations; where classical sources disagree, the disagreement is an explicit policy switch or a recorded note — never a silent choice.

- **Sidereal foundation** — 40+ ayanamsa systems including star-anchored "True" ayanamsas; 27-nakshatra system; Panchanga.
- **Pancha Pakshi** — an explicitly named Agastya-attributed Madras 1879
  aksara/query-or-name-initial fixed-clock schedule and directed relationship
  profile, with exact rational timing, source locators, declared omissions,
  and no implicit or universal default. A separate astronomical-paksha product
  evaluates apparent geocentric Moon-minus-Sun longitude in the true ecliptic
  of date and maps `[0, 180)` Shukla/waxing to the profile's source-attested
  Purva label and `[180, 360)` Krishna/waning to Amara. It accepts no location
  and never selects a schedule, materializes a clock, supplies paksha to another
  operation, or infers natal identity. An explicit modern local-solar context
  policy can derive topocentric day/night and local-mean-solar weekday for an
  aware instant and location while requiring the caller to supply Purva or
  Amara. A separate modern fixed-clock policy anchors the selected schedule at
  sunrise or sunset, treats one nazhigai as exactly 1,440 SI seconds on
  reader-bound TT, and publishes half-open UT1 cell intervals plus their
  unclipped relation to the astronomical half end. A separately named
  solar-half-first selector returns the unique current fixed-clock cell under
  exact half-open TT ownership, or the explicit
  `unmaterialized_solar_half_tail` status when a long solar half outlasts the
  fixed span. A distinct modern solar-proportional policy can instead preserve
  the exact nominal offset fractions and map them independently across the
  complete governing day or night half on reader-bound TT, returning 25
  half-open TT/UT1 cells with exact astronomical-boundary closure. The 1879
  witness is not credited with that proportional rule. A separate
  solar-half-first selector identifies the unique proportional cell through
  exact half-open TT ownership; complete-half coverage means its lawful status
  is always `selected`, with no fixed-clock tail or fallback. Paksha remains
  caller supplied on every schedule, materialization, and current-cell surface;
  the standalone astronomical inference is never applied automatically, and
  the 1879 profile remains explicitly non-natal. A pure Stage 2I lookup exposes
  the selected 1879 generator's first-samam EAT seed from explicit profile
  Paksha, day/night half, and weekday. It does not materialize the schedule or
  promote that seed into a whole-day eating bird, Padu, authority,
  Adhikara/Bharana, condition, score, or forecast. All 28 cells are directly
  bound to the governing 1879 leaves and separately corroborated by the 1934
  Uromarisi publication; textual-lineage independence is not claimed. A
  separate named Bogamuni 2024
  profile preserves a complete 54-cell Purva/Amara-by-nakshatra bird table.
  Its Amara verse governs because the adjacent commentary duplicates Shravana
  and omits Revati; that malformed commentary remains visible as rejected
  conflict evidence. The fixed modern
  `bogamuni_2024_apparent_lahiri_natal_moon_identity_v1` composition evaluates
  apparent geocentric Sun and Moon positions on one reader-bound TT epoch,
  derives the source-mapped lunar half, applies Lahiri true ayanamsa, assigns
  the Moon to one of 27 equal half-open nakshatras, and returns the selected
  source-table bird with every intermediate and locator visible. The source
  attests nakshatra birds and phase labels; birth-Moon application, Lahiri, and
  the equal-sector boundary policy are explicitly Moira-owned, not source
  claims. It never routes into a schedule, current cell, score, or forecast. A
  third source-scoped Bogamuni 2024 profile,
  `bogamuni_chennai_2024_padu_bird_mapping`, preserves the separate 14-cell
  Purva/Amara-by-weekday Padu-bird table. It is a pure explicit-label lookup:
  the source table has no day/night axis, and its death-or-inoperative bird is
  not relabelled as a schedule `RULE` activity, a generic authority bird, or
  the separately labelled eating bird. The primary witnesses do not present an
  `Adhikara Pakshi` table, while Bharana is secondary terminology only; neither
  alias nor product is admitted. The Padu profile performs no natal identity,
  astronomical routing, schedule/current-cell selection, condition scoring,
  or forecast.
- **Dashas** — Vimshottari with nakshatra balance; Chara Dasha (K.N. Rao's named lineage); Varshaphal (annual charts).
- **Vargas** — divisional charts (navamsa, dashamansa, dwadashamsa, saptamsa, trimshamsa, and more); Vimshopaka Bala (BPHS 20-point varga-dignity strength over all four classical groups) with vargottama detection.
- **Yogas** — 60 classical yogas across six families (Pancha Mahapurusha, Chandra, Surya, all 32 Nabhasa, Raja core, Dhana core), each returned as a proof object: formation conditions with observed evidence, cancellation (bhanga) clauses evaluated first-class, and per-yoga primary-source citations.
- **Shadbala** — the complete six-fold strength system plus Bhava Bala (house strength), inline Ishta/Kashta Phala on every planet, and Graha Yuddha transfer disclosure.
- **Ashtakavarga** — bindu tables plus kakshya-level transit evaluation (Saturn-first lord order) and Shodhya Pinda, validated to the digit against BPHS Ch. 69's own worked example.
- **Upagrahas** — the five kalavelas (Gulika, Kala, Mrityu, Ardhaprahara, Yamaghantaka) with portion-point, Mandi-mode, and lord-sequence lineage policies, plus the five Sun-derived upagrahas.
- **Avasthas** — Baladi, Jagradadi, and Deeptadi as per-source rule tables (BPHS / Saravali / Jataka Parijata / Phaladeepika, never merged), plus the six non-exclusive Lajjitadi flags with evidence strings.
- **Jaimini** — rasi drishti, arudha padas A1–A12 (Rath/JHora exception default, Raman variant as policy), argala with virodha pairs, and karakamsa with both lineage readings named (Rath D9 vs. K.N. Rao D1).
- **Muhurta** — Tara Bala (nine-tara cycle) and Chandra Bala (Chandra Shuddhi with Chandrashtama flagged) as a natal-personalized electional overlay.
- **Sade Sati** — phase classification (rising/peak/setting) with Ashtama and Kantaka Shani flags, and kernel-timed phase windows via Saturn sidereal sign-ingress bisection, with retrograde re-entries reported as separate windows.

### Advanced Astronomy

- **Eclipses** — NASA-canon contact solver for solar and lunar eclipses; Saros series classification with heptagonal vertex labelling; local circumstance computation.
- **Heliacal phenomena** — heliacal rising and setting; acronychal rising and setting; planetary elongation extremes.
- **Parans** — paranatellonta field analysis with contour extraction and stability metrics.
- **Occultations** — lunar occultation of stars and planets; close-approach detection.
- **Stations** — retrograde stations with precise stationary-point search.
- **Mapping** — Astrocartography (ACG) lines for all planets; Local Space chart positions; Gauquelin sectors.
- **Galactic coordinates** — full equatorial-to-galactic transform and reference point catalog.
- **Temporal systems** — 28-mansion Arabic lunar stations (Manazil); Sothic cycle drift and Egyptian civil calendar conversion; void-of-course Moon windows.
- **Harmograms** — intensity-spectrum research engine (H1–H5); spectral vectors, zero-Aries parts construction, intensity doctrine, and time-domain trace analysis.
- **Harmonics** — harmonic chart calculation, aspect-harmonic profiles, vibrational fingerprint analysis.
- **Synastry** — inter-chart aspects, house overlays, composite chart (midpoint method), Davison chart (spherical midpoint).
- **Jones chart shapes** — all 7 temperament types.

---

## Quick Start

Moira initializes even when no planetary kernel is present. Kernel-dependent operations (for example `chart()`) raise a clear `MissingEphemerisKernelError` until a kernel is configured. See [Kernel Setup](#kernel-setup) below before executing planetary examples.

```python
from datetime import datetime, timezone
from moira import Moira

m = Moira()

# 1. Planetary positions
chart = m.chart(datetime(2000, 1, 1, 12, 0, tzinfo=timezone.utc))
print(f"Sun:  {chart.planets['Sun'].longitude:.6f} deg")
print(f"Moon: {chart.planets['Moon'].longitude:.6f} deg")

# 2. House cusps (Placidus, London)
from moira import HouseSystem
houses = m.houses(
    datetime(2000, 1, 1, 12, 0, tzinfo=timezone.utc),
    latitude=51.5074,
    longitude=-0.1278,
    system=HouseSystem.PLACIDUS,
)
print(f"ASC: {houses.asc:.4f} deg  |  MC: {houses.mc:.4f} deg")

# 3. Aspect patterns
from moira.patterns import find_all_patterns
patterns = find_all_patterns(chart.longitudes())
for p in patterns:
    print(f"{p.name}: {', '.join(p.bodies)}")

# 4. House placement lookup
from moira.houses import house_of
sun_house = house_of(chart.planets['Sun'].longitude, houses)
print(f"Sun is in house: {sun_house}")
```

---

## REST API Server

The engine ships with an optional FastAPI transport layer (`moira_server`) that exposes the admitted engine surface as typed, versioned REST routes.

```bash
pip install moira-astro[server]
uvicorn --factory moira_server:create_app
```

For latency-sensitive deployments, opt in to one bounded per-worker startup
warmup before accepting computational traffic:

```powershell
$env:MOIRA_SERVER_PREWARM = "1"
uvicorn --factory moira_server:create_app
```

With prewarm enabled, `/ready` returns HTTP 503 until the kernel-backed warmup
succeeds; `/health` remains available for liveness diagnostics. Prewarm is
disabled by default because each worker pays its own native memory cost.

- **60+ route families under `/v1`** — charts, positions, houses, per-stage pipeline visibility, progressions (the full dispatched method menu advertised as OpenAPI enums), primary directions, returns, transits, dashas and time lords, the complete Vedic suite (yogas, shadbala, ashtakavarga, upagrahas, avasthas, Jaimini, muhurta, sade sati), draconic charts, astrocartography, asteroids and comets, fixed stars, harmonics, harmograms, electional scoring, synastry and relationship products, and more.
- **Typed transport** — every route family has dedicated Pydantic request/response models, serializers, and services; doctrine stays in the engine, the server is transport and orchestration only.
- **OpenAPI discovery** — tagged schema with installed discovery metadata for machine consumers.

---

## Requirements and Installation

- Python 3.10 or later
- A C++ compiler, `cmake >= 3.24`, and `pybind11 >= 2.12` (required at build time for the native extension)
- A JPL DE-series planetary kernel (de430, de440, or de441 — not bundled; see below)

```bash
# Standard install (builds the native C++ extension)
pip install moira-astro

# With the FastAPI REST server (fastapi, uvicorn, pydantic)
pip install moira-astro[server]

# With Lunar Graze support (spiceypy, laspy, requests)
pip install moira-astro[lunar-graze]
```

---

## Kernel Setup

Moira requires a JPL DE-series SPK planetary kernel for all planetary computation. No kernel is bundled — the files are large and the choice of release belongs to the user.

All kernel reading is performed by Moira's own native C++ SPK/DAF reader. As of 4.0.0 there is no `jplephem` runtime fallback: segment types outside the native reader's support raise an explicit error rather than silently routing through a third-party library.

**Supported kernels:**

| Kernel | File | Size | Date range | Notes |
| :--- | :--- | :--- | :--- | :--- |
| DE441 | `de441.bsp` | ~3.1 GB | ~13 200 BCE – ~17 200 CE | Original design target; maximum date coverage |
| DE440 | `de440.bsp` | ~114 MB | 1550 BCE – 2650 CE | Current JPL standard; recommended for most users |
| DE430 | `de430.bsp` | ~128 MB | 1550 BCE – 2650 CE | Widely deployed predecessor to DE440 |

### Kernel Manager (GUI)

The easiest way to download and configure a kernel is the built-in Tkinter interface. It requires no extra dependencies — Tkinter ships with CPython on all platforms.

```bash
moira-kernel-manager
```

The window shows all supported kernels with extended descriptions (design rationale, date coverage, size trade-offs), live Installed/Missing status for each, and a real progress bar for downloads. You can also point Moira at a `.bsp` file already on disk without re-downloading.

What the GUI provides:

- **Kernel list** — planetary (de430, de440, de441) and supplemental (asteroids, small bodies) sections with size, date range, and status per row.
- **Detail panel** — selecting a row shows a full description of that kernel's coverage, accuracy, and when to prefer it over the alternatives.
- **Download with progress** — streams the selected kernel in the background; a progress bar tracks bytes received. A Cancel button interrupts the transfer and removes the partial file.
- **Use selected** — activates an installed kernel for the current session via `set_kernel_path()`.
- **Browse…** — open any `.bsp` file already on disk and set it as the active kernel immediately.

### CLI

```bash
# List all kernels and their status
moira-download-kernels --list

# Download all missing kernels (interactive prompt)
moira-download-kernels

# Download without prompting
moira-download-kernels --yes
```

### SPK Kernel Writer (GUI)

Moira supports building custom Type 13 SPK kernels using an integrated compiler GUI (built on Tkinter). This utility fetches physical position vectors directly from the JPL Horizons API and packages them into a native-readable binary kernel (`.bsp`).

```bash
moira-daf-writer
```

What the custom kernel writer provides:
- **Guided Horizons Import**: Search the JPL Small Body Database (SBDB) by designation or name for any numbered asteroid or comet.
- **Custom Parameter Controls**: Configure start/end Julian Days, step size in days, interpolation center, and coordinate frame.
- **Verification Loop**: Automatically runs a post-compilation check to verify segment availability and test coordinate evaluations.

### Engine readiness model

- `Moira()` succeeds even if no kernel is installed. It auto-discovers any compatible kernel in the standard locations.
- `m.is_kernel_available()` reports kernel readiness.
- `m.get_kernel_status()` explains expected paths and remediation.
- `m.available_kernels` lists installed planetary kernels (small-body shard catalogs are discovered separately via their manifests).
- Kernel-dependent calls raise `MissingEphemerisKernelError` with instructions.

**Standard location:** `kernels/<filename>.bsp` relative to the repository root, or `~/.moira/kernels/`. The engine resolves either automatically.

**Custom location:** pass the path at construction, or call `set_kernel_path()` before the first `Moira()` instantiation:

```python
from moira.spk_reader import set_kernel_path
from moira import Moira

set_kernel_path("/path/to/de440.bsp")
m = Moira()

print(m.is_kernel_available())
print(m.get_kernel_status())
print(m.available_kernels)
```

**Direct download links (JPL SSD):**

- DE441: [https://ssd.jpl.nasa.gov/ftp/eph/planets/bsp/de441.bsp](https://ssd.jpl.nasa.gov/ftp/eph/planets/bsp/de441.bsp)
- DE440: [https://ssd.jpl.nasa.gov/ftp/eph/planets/bsp/de440.bsp](https://ssd.jpl.nasa.gov/ftp/eph/planets/bsp/de440.bsp)
- DE430: [https://ssd.jpl.nasa.gov/ftp/eph/planets/bsp/de430.bsp](https://ssd.jpl.nasa.gov/ftp/eph/planets/bsp/de430.bsp)

### Small-Body Catalogs (Asteroids and Comets)

The unified asteroid catalog (1,382 bodies as 56 Type-13 shards) and the numbered periodic comet catalog (497 comets as 20 shards) are too large to ship inside the wheel and are distributed as separate downloads. Install a catalog by placing its shard directory — `asteroids/` or `comets/`, each containing its shards and `manifest.json` — under any kernel search root (`kernels/` at the repository root or `~/.moira/kernels/`). The engine discovers every manifest under every search root automatically; no configuration call is required.

Note for pre-4.0.0 installs: the single-file supplemental kernels (`comets.bsp`, `centaurs.bsp`, `minor_bodies.bsp`) no longer auto-load. All small bodies now resolve through the sharded manifests.

---

## Data Inventory

| Layer | Source | Bundled | Note |
| :--- | :--- | :--- | :--- |
| IAU 2000A/2006 nutation and precession tables | IAU | Yes | 2,414 terms; native C++ (`_moira_native`) |
| DE-series planetary kernel | JPL | No | de430 (~128 MB), de440 (~114 MB), or de441 (~3.1 GB); download separately |
| Named star registry | Sovereign (`star_registry.csv` + JSON provenance) | Yes | 1,809 stars; license-independent |
| Unified asteroid catalog | JPL Horizons | No | 1,382 asteroids across all 119 families; 56 Type-13 shards, 1600–2500 CE; separate download, manifest-discovered |
| Numbered periodic comet catalog | JPL Horizons | No | 497 comets (1P–516P); 20 Type-13 shards, 1600–2500 CE; separate download, manifest-discovered |

---

## Native C++ Performance

Moira's computational core (`_moira_native`) is implemented in C++17 and compiled as a pybind11 extension at install time. Performance-critical paths — IAU 2000A nutation evaluation, SPK/DAF kernel reading, apparent planetary evaluation (via `NativePlanetaryEvaluator`), coordinate transforms, light-time iteration, harmogram computation, precession, and event searching — execute natively without Python overhead.

This matters most in phenomenon-searching loops (retrograde periods, eclipse searches, heliacal events, conjunction sweeps) where core transforms are evaluated thousands of times. The native extension is a required component and is built automatically during `pip install`.

---

## Validation Evidence

Moira is validated as a three-layer corpus. Each layer has its own correct evidence standard.

**Astronomy layer** — authoritative physical oracles first, enforced regression thereafter.
References: IAU ERFA/SOFA, JPL Horizons, NASA catalogs, IERS.

**Astrology layer** — external chart software where stable and meaningful; doctrine-grounded invariants where no universal oracle exists.
References: Swiss Ephemeris, Astro.com, canonical doctrine tables, structural invariants.

**Experimental layer** — subsystem-specific surfaces for sovereign or modern domains.
Domains: sovereign fixed stars, variable stars, multiple star systems, galactic transforms, eclipse Saros classification.

Every validated claim must pass three gates:

1. **Gate of Source** — inputs and reference data are tied to an independent authority.
2. **Gate of Flow** — the computational path is explicit and inspectable.
3. **Gate of Oracle** — outputs are benchmarked against an external reference appropriate to the domain.

When residuals remain, Moira documents them as model-basis differences rather than mislabeling them as engine defects. Two systems may be internally correct while answering different mathematical questions because of differing assumptions — for example, Delta-T branch, retarded-versus-geometric Moon treatment, or event-definition objective.

| Report | Verification Source |
| :--- | :--- |
| [`VALIDATION_ASTRONOMY.md`](wiki/03_validation/VALIDATION_ASTRONOMY.md) | IAU ERFA/SOFA, JPL Horizons, NASA. Geocentric residual: 0.576 arcseconds (documented Delta-T divergence). |
| [`VALIDATION_ASTROLOGY.md`](wiki/03_validation/VALIDATION_ASTROLOGY.md) | Swiss Ephemeris, Astro.com, canonical doctrine tables. Houses, ayanamshas, predictive cycles. |
| [`VALIDATION_EXPERIMENTAL.md`](wiki/03_validation/VALIDATION_EXPERIMENTAL.md) | SOFA/ERFA, Swiss swetest, AAVSO, GCVS, binary orbit ephemerides. Sovereign stars, variable stars, multiple systems. |

---

## The Reduction Pipeline

```mermaid
graph TD
    A[JPL Planetary Kernel\nChebyshev state vectors] --> B[SSB Barycentric Position\nkm · ICRF]
    C[Sovereign Star Registry\n1809 named stars] --> D[Stellar Astrometric Position\nproper motion · parallax]
    B --> E[1 · Light-Time Iteration\nbody at t − τ  where τ = d/c]
    E --> F[2 · Gravitational Deflection\nSun · Jupiter · Saturn · Earth]
    F --> G[3 · Annual Aberration\nrelativistic · IAU SOFA]
    G --> H[4 · IAU 2006 Frame Bias\nICRF → Mean Equator J2000]
    D --> H
    H --> I[5 · IAU 2006 Precession\nP03 polynomial series]
    I --> J[6 · IAU 2000A Nutation\n1365 lunisolar + 687 planetary terms]
    J --> K[True Equinox and Equator of Date]
    K --> L[7 · Topocentric Parallax\nWGS-84 · optional]
    K --> M[8 · Atmospheric Refraction\nSky positions only · optional]
    K --> N[Ecliptic Projection\nTrue obliquity of date]
    N --> O[Zodiacal Longitude · Latitude · Distance]
    K --> P[Sidereal Frame · Ayanamsa\noptional]
    K --> Q[House Cusps · 22 Systems\nrequires lat/lon]
```

### Worked Example: Mars at J2000.0

The following traces every pipeline stage for Mars on 2000 January 1, 12:00 TT, using live DE441 kernel data. All numbers are from the running engine.

**Time:** JD_UT 2451545.000000 → JD_TT 2451545.000739 &nbsp;(ΔT = +63.807 s)

| Step | Operation | Vector / Value | Shift from Previous |
| :---: | :--- | :--- | :--- |
| 0 | **DE441 kernel read** — SSB → Mars | (206,980,508.6, −184,891.6, −5,666,529.8) km | — |
| 0 | **DE441 kernel read** — SSB → Earth | (−27,568,641.0, 132,361,060.2, 57,418,514.1) km | — |
| 0 | **Geometric geocentric** — Mars − Earth | distance: 276,697,408.2 km = 1.849608 AU | — |
| 1 | **Light-time iteration** — Mars at t − τ | τ = 0.010683 days = **15.383 min** | **15.761 arcsec** |
| 2 | **Gravitational deflection** — Sun + Jupiter + Saturn | sub-arcsecond bending of light path | **0.006 arcsec** |
| 3 | **Annual aberration** — Earth velocity 29.786 km/s | relativistic displacement toward apex | **14.070 arcsec** |
| 4 | **IAU 2006 frame bias** — ξ₀ = −16.617 mas, dε₀ = −6.819 mas | fixed ICRF → mean equinox J2000 rotation | **0.023 arcsec** |
| 5 | **IAU 2006 precession** — P03 polynomial series | negligible at J2000 (reference epoch) | **0.016 arcsec** |
| 6 | **IAU 2000A nutation** — Δψ = −13.932″, Δε = −5.769″ | true equator and equinox of date | **14.351 arcsec** |
| 7 | **Ecliptic projection** — true obliquity ε = 23.437677° | λ = **327.963300°** · β = −1.067779° · d = 1.849688 AU | — |

**Final position: Aquarius 27° 57′ 48″** &nbsp;·&nbsp; distance 1.8497 AU &nbsp;·&nbsp; speed +0.7757°/day (direct)

**Total pipeline correction from geometric to apparent: −43.760 arcsec**

The largest contributors are nutation (−13.932″), annual aberration (−14.070″), and the combined light-time displacement (−15.761″). Gravitational deflection (0.006″) and frame bias (0.023″) are sub-arcsecond but non-negligible at sub-arcsecond accuracy targets.

### Pipeline Controls

Each correction stage can be toggled independently via `planet_at()`. The table below shows the measurable effect of disabling each stage on the Mars J2000.0 result.

| Parameter | Default | Effect on Mars J2000.0 longitude | Function |
| :--- | :--- | :--- | :--- |
| `apparent=True` | `True` | Full pipeline active | `planet_at()` |
| `apparent=False` | — | Geometric position; all corrections skipped. Δ = **+43.760 arcsec** | `planet_at()` |
| `aberration=False` | — | Aberration stage skipped. Δ = **+14.069 arcsec** | `planet_at()` |
| `grav_deflection=False` | — | Deflection stage skipped. Δ = **+0.003 arcsec** | `planet_at()` |
| `nutation=False` | — | Nutation skipped; mean equinox used. Δ = **+13.932 arcsec** | `planet_at()` |
| `observer_lat/lon` | `None` | When supplied, adds topocentric parallax (WGS-84). Effect: ~1° for Moon, <0.01″ beyond Jupiter | `planet_at()` |
| `refraction=True` | `True` | Atmospheric refraction applied to altitude. Effect: ~0.57° at horizon | `sky_position_at()` |
| `delta_t_policy` | `None` | Controls UT → TT conversion branch (IERS tables, polynomial, hybrid physical) | both |

---

## Project Documentation

The canonical documentation tree lives in `wiki/`. The flat `moira.wiki/` Git wiki mirror is generated from it by `python scripts/sync_git_wiki.py` and should not be edited by hand.

| Document | Contents |
| :--- | :--- |
| [`01_LIGHT_BOX_DOCTRINE.md`](wiki/01_doctrines/01_LIGHT_BOX_DOCTRINE.md) | Transparency and derivation as design constraints. |
| [`BEYOND_SWISS_EPHEMERIS.md`](wiki/01_doctrines/BEYOND_SWISS_EPHEMERIS.md) | Capabilities enabled by sovereign catalogs, explicit policy, and modern Python. |
| [`HOUSE_SYSTEM_DIVERGENCE.md`](wiki/01_doctrines/houses/HOUSE_SYSTEM_DIVERGENCE.md) | House-system derivation and discretionary divergence from conventional Swiss-facing behavior. |
| [`CONSTITUTIONAL_PROCESS.md`](wiki/00_foundations/CONSTITUTIONAL_PROCESS.md) | The Subsystem Constitutional Process — the development and governance protocol. |
| [`MOIRA_ROADMAP.md`](wiki/06_roadmap/MOIRA_ROADMAP.md) | Feature implementation status and mathematical accuracy register. |

---

## License

MIT (c) 2026 TheDaniel166. See [PROVENANCE.md](PROVENANCE.md) for license and Swiss-lineage provenance clarity.
