# Changelog

## 1.0.0 — 2026-08-03

First stable production release of the SiriusX astronomy platform.

### Stable API

- Freezes the 12 documented public package entry points.
- Promotes the complete `1.0.0-rc.2` implementation without breaking API changes.
- Publishes stable releases to npm under the `latest` distribution tag.

### Included

- Real-catalog stellar astrometry with explicit accuracy profiles and staged coordinate outputs.
- UTC, TAI, TT, UT1, leap-second, DUT1, and Earth-orientation support.
- Catalog validation, lookup, cone search, async/streaming access, and packed formats.
- Observation planning, rise/transit/set, twilight, visibility, airmass, and coordinate utilities.
- All 88 IAU constellation identities with optional boundary and line-data integration.
- Sun, Moon, Mercury through Neptune, and minor-body calculations.
- Full-vector topocentric Solar System correction, corrected lunar distance and phase geometry, and explicit center/upper-limb event modes.
- Canvas, SVG, WebGL point-buffer, React, and Vue integration entry points.
- Zero runtime dependencies, ESM/CommonJS builds, TypeScript declarations, and production package validation.

### Accuracy boundary

SiriusX 1.0.0 is stable for web planetariums, education, catalog exploration, object-finding interfaces, and general observation planning. Compact lunar, planetary, refraction, aberration, nutation, and deflection models remain approximate; this release is not certified for spacecraft navigation, eclipse or occultation prediction, professional astrometric reduction, or workflows requiring a guaranteed sub-arcsecond error budget.

## 1.0.0-rc.2

Solar System accuracy and observer-geometry hardening release candidate.

### Improved

- Replaced altitude-only/absent lunar parallax behavior with full 3D topocentric vector subtraction for every Solar System body.
- Added geocentric and topocentric equatorial outputs, topocentric distance, horizontal parallax, sidereal time, hour angle, and correction metadata.
- Added dominant lunar distance perturbation terms, physically derived angular diameter, and distance-aware Sun–Moon–Earth phase geometry.
- Added `calculateSolarSystemEvents()` for Sun, Moon, and planets with explicit center/upper-limb and standard/no-refraction modes.
- Refined transit times after the sampled search.
- Added frozen external-reference tests for Sun/Moon observer positions, lunar distance/illumination, and lunar events.
- Increased the automated suite from 22 to 26 tests.

### Documentation

- Consolidated fragmented documentation into one canonical production guide per concern.
- Removed internal handoffs, validation reports, duplicate documentation indexes, roadmap notes, and playground-only Markdown from the release tree.
- Added concise contribution and security policies for the source repository.

### Architecture decision

SiriusX remains the shared astronomy kernel. Helios and Luna should consume SiriusX in future specialized releases rather than replacing SiriusX calculations or becoming required SiriusX dependencies.

### Measured audit result

Across 700 observer cases, mean Moon sky-position error improved from about `0.781°` to `0.043°`; mean lunar distance error improved to about `0.062%`. These are test-grid measurements, not universal guarantees.

## 1.0.0-rc.1

Feature-complete 1.0 astronomy platform release candidate.

### Added

- Explicit `fast`, `visual`, `observational`, and `precision` accuracy profiles.
- UTC, TAI, TT, and UT1 time-scale conversion with leap-second support.
- Earth-orientation records, interpolation, DUT1, and polar motion.
- Stage-preserving observed-place pipeline with compact nutation, aberration, solar deflection, topocentric parallax, refraction, radial velocity, and perspective propagation.
- Catalog validation, aliases, cone search, JSON, async, streaming, and typed-array packing.
- Rise/set/transit, visibility windows, twilight, separation, position angle, airmass, and coordinate formatting.
- All 88 IAU constellation identities and external boundary resolver architecture.
- Sun, Moon, seven-planet approximate ephemerides and elliptical minor-body propagation.
- Canvas projections, labels, constellation lines, view controls, and hit testing.
- SVG renderer, WebGL point-buffer adapter, and dependency-injected React/Vue components.
- Expanded module budgets, package validation, tests, and large-catalog benchmark.

### Accuracy note

The compact observed-place and Solar System models are intended for visual astronomy and observation planning. This prerelease was not presented as a certified sub-arcsecond system.

## 0.2.0

Breaking astronomy-first rebuild. Removed the original procedural starfield direction and introduced real catalog-star calculations.