Earth's favorite natural satellite. Stable, predictable, and mostly bug-free for past 3 billion years.
The Moon is a rocky, airless world that orbits Earth at an average distance of 384,400 km. It is the fifth largest satellite in the Solar System and the only celestial body visited by humans. This repository contains the complete changelog, architecture documentation, and API reference for the Moon's 4.51-billion-year development history.
⚠️ Deprecation Notice: Major volcanic activity was deprecated in v2.0.0 (3.2 Ga). The product is now in maintenance mode. Recent patches (v2.2.x) suggest some legacy thermal systems may still be active. Do not rely on volcanism for new projects.
- Tidal Synchronization: Fully tidally locked to Earth. One face always visible. No configuration required.
- Phase Cycling: 29.53-day release cycle with 8 distinct visual modes (New, Waxing Crescent, First Quarter, Waxing Gibbous, Full, Waning Gibbous, Third Quarter, Waning Crescent).
- Tide Generation: Produces oceanic tides with amplitude up to 18.6-year modulation cycles. Compatible with all major ocean basins.
- Eclipse Support: Both solar (total, annular, partial, hybrid) and lunar (total, partial, penumbral) eclipse modes available on predictable schedules.
- Regolith Surface: Fine-grained, impact-generated surface layer with excellent preservation properties. Ideal for archiving impact history.
- Low Atmosphere: Zero atmospheric interference for optical and radio astronomy. UV and X-ray transparent.
- Stable Orbit: Slowly receding at 3.8 cm/year. Will remain bound to Earth for approximately 5 billion years.
The Moon is visible to the naked eye from any location on Earth with clear skies. No installation required.
# Basic usage
$ look_up --direction east --time evening
# With optical enhancement
$ telescope --aperture 200mm --target moon
# High-resolution imaging
$ space_probe --mission "Lunar Reconnaissance Orbiter" --resolution 0.5m
⚠️ Requires Level 3 clearance (Apollo, Luna, or Chang'e certification).
$ lunar_module --landing-site "Mare Tranquillitatis" --sample-return true| Component | Requirement |
|---|---|
| Primary Body | Earth (mandatory) |
| Star | Sun (recommended for illumination) |
| Orbit | ~384,400 km semi-major axis |
| Mass | 7.342 × 10²² kg |
| Mean Radius | 1,737.4 km |
| Surface Gravity | 1.62 m/s² (16.5% of Earth) |
| Escape Velocity | 2.38 km/s |
| Day Length | 29.53 Earth days (synchronous) |
See docs/ARCHITECTURE.md for detailed information about the Moon's internal structure, crustal asymmetry, and thermal evolution.
See docs/API.md for the complete public interface including phases, illumination, and eclipse calculations.
See CHANGELOG.md for the complete version history from v0.1.0-alpha (4.51 Ga) to present.
- #0001: Far side crust is ~30 km thicker than near side. This is a known design asymmetry, not a bug. See docs/ARCHITECTURE.md.
- #0002: No atmosphere. Not fixable without breaking changes to surface temperature and impact preservation.
- #0003: Water ice only available in permanently shadowed polar regions. Limited distribution.
- #0004: Regolith is extremely abrasive. Causes accelerated wear on mechanical components (Apollo suits, rovers, etc.).
- #0005: Moon is slowly receding from Earth at 3.8 cm/year. Will eventually break tidal lock, but not within warranty period.
- #0006: Recent evidence (v2.2.3) suggests volcanic activity as recent as 100 Ma. Legacy thermal system may not be fully shut down.
- #0007: Shrinking radius causing tectonic moonquakes (2026 research). Ongoing monitoring required.
We welcome contributions! See CONTRIBUTING.md for guidelines on sample return missions, orbital insertions, and impact crater naming conventions.
The Moon is released under the MIT License. No attribution required, though we appreciate citations in peer-reviewed literature.
- Theia — Original contributor. Merged into Earth in v0.1.0-alpha. RIP.
- Apollo Program — First user testing and sample return (1969–1972).
- Luna Program — Early robotic testing (1959–1976).
- Chang'e Program — Recent sample return and far side exploration (2013–present).
- Lunar Reconnaissance Orbiter — High-resolution surface monitoring since 2009.
- Solar System — Original hosting provider.
"That's one small commit for man, one giant repository for mankind."
Last updated: 2026-08-01