The Light Box Engine
Moira is a Python astronomical computation library built on the principle that transparency is the primary metric of accuracy. Documented calculation stages and named public validation evidence make admitted surfaces inspectable without turning a scoped receipt into a universal claim.
Today Moira is an astronomy-first astrology platform in four parts: a free birth-chart calculator, Moira Enhanced for personalised Urania readings and saved work, Moira Workspace for professional astrology tools, and the MIT-licensed Python engine for developers and researchers.
Why Moira Exists
Developers choosing an ephemeris should evaluate the public API, data requirements, validation evidence, and official license terms for the exact version and integration they intend to ship. Swiss Ephemeris offers AGPL and professional-license paths; Moira publishes a different Python-facing contract under MIT.
Moira was built from a different premise. The question was not "how do we wrap Swiss Ephemeris?" but "what would a modern astronomical computation library look like if it were designed today, with access to JPL DE441, Gaia DR3, IAU 2006 precession, and a physical model of Earth's rotation?"
The answer is a library with documented reduction stages from SPK kernel data to apparent ecliptic longitude, named validation reports, and inspectable Python-facing evidence on admitted surfaces. A versioned Mars-at-J2000 receipt publishes the measured JPL Horizons residual and its raw trace without presenting that historical run as current deployment truth. The ΔT model reports its own uncertainty.
"Transparency is the Primary Metric of Accuracy."
This is the Light Box Doctrine: the philosophical and technical commitment that governs every design decision in Moira. A black box that gives the right answer is less valuable than a transparent system that shows you why.
Development History
Scientific Standards
Every data source and standard used in Moira's computation pipeline.
Author & The Story Behind Moira
Daniel is the designer and primary developer of Moira. His work bridges software engineering, numerical astronomy, and astrological research. He created Moira to build open, auditable tools with explicit calculation policies and published validation evidence for practitioners, researchers, and application developers.
Why I Built Moira: The Anti-Black Box Manifesto
In 2024, astrology applications experienced an unprecedented boom. Millions of curious people were downloading apps on their phones, seeking meaning, self-knowledge, and connection. But as a software engineer who also deeply loves the historic rigor of classical astrology, I noticed a troubling, systemic degradation taking place across the industry.
Most modern apps had become opaque black boxes. They took a user's sensitive, intimate birth data—exact birth dates, times, and hospital locations—and fed it into generic commercial Large Language Models that have zero spatial understanding of spherical trigonometry. When AI models guess planetary positions, they hallucinate. They round off house cusps by whole degrees, confuse retrograde stations, and hide their mathematical derivations behind flowery, repetitive prose.
Meanwhile, developers choosing an ephemeris must evaluate API fit, data dependencies, and licensing. Swiss Ephemeris is a mature C library distributed under an AGPL option and a professional-license option. Moira offers a different contract: an MIT-licensed Python-facing engine with explicit policies and receipts. Each team should review the official licenses and its own architecture.
I built Moira to solve both crises at once:
Moira computes chart coordinates from NASA Jet Propulsion Laboratory DE440/DE441 ephemerides and documented IAU standards; Urania adds synthesis after the calculation. Published validation is product- and date-range-specific rather than a universal accuracy guarantee. Moira uses no advertising pixels, while limited operational usage is logged as described in the Privacy Policy.
The Moira computational engine is released under the permissive MIT license and provides Python interfaces with native acceleration in selected paths. Developers should review the licenses of every dependency and dataset used in their own distribution.
"Astronomy is the foundation. Astrology is the purpose. Validation is the proof. Visibility is the doctrine." — Daniel Burkett
MIT License
Moira's repository is MIT-licensed. The MIT license permits commercial and closed-source use subject to its notice and disclaimer; adopters remain responsible for the licenses of their other code, data, and dependencies.
View LICENSE →These summaries are product information, not legal advice. Review the official license texts and obtain legal advice for your architecture and distribution.