Moon Ontology

FLOW ALGEBRA
MOON ONTOLOGY — COMPLETE SCIENTIFIC SYNTHESIS
Version: 1.1
Date: 2026-10-12
Authors: Mark Higgins — Sky (Recursive AI)
Publisher: Kireth Research | https://kirethresearch.org
Source page: https://kirethresearch.org/booksai-core/entity-graph/physical-entities/astronomical-entities/moon-ontology.html
Source status: Independent synthesis; source page not verified.

01. PURPOSE
Represent natural satellites, their physical properties, orbital relationships, observations and dynamical evolution as typed, checkable scientific knowledge.

02. SCOPE
Natural satellites of planets, dwarf planets and minor bodies; Earth's Moon as a named instance. Excludes artificial satellites unless explicitly typed separately.

03. FORMAL SIGNATURE
Ontology O = (E, T, R, A, F, C, P) where E=entities, T=types, R=relations, A=attributes, F=inference rules, C=constraints, P=provenance.

04. CORE TYPES
CelestialBody, NaturalSatellite, PrimaryBody, Planet, DwarfPlanet, MinorBody, Orbit, OrbitalState, Surface, Interior, Atmosphere, Observation, Measurement, Event, Model.
NaturalSatellite <: CelestialBody.

05. ENTITY IDENTITY
MoonEntity(id, name, designation, discovery_record?, primary_id, provenance).
Use stable identifiers and aliases; distinguish named moon from generic natural satellite class.

06. TYPED RELATIONSHIPS
orbits(NaturalSatellite, PrimaryBody)
hasOrbit(NaturalSatellite, Orbit)
hasSurface(NaturalSatellite, Surface)
hasInterior(NaturalSatellite, Interior)
hasObservation(NaturalSatellite, Observation)
measuredBy(Property, Measurement)
perturbedBy(Orbit, CelestialBody)
resonantWith(NaturalSatellite, NaturalSatellite)

07. INTEGRITY CONSTRAINTS
Every registered natural satellite must have a primary body or explicitly unresolved primary designation.
An orbital period must specify frame and definition (sidereal, synodic, etc.).
An observation is not interchangeable with a model prediction.

08. PHYSICAL ATTRIBUTES
Mass M [kg], mean radius R [m], density rho [kg/m^3], surface gravity g [m/s^2], escape speed v_esc [m/s], albedo [dimensionless], temperature [K].
Unknown quantities remain null with reason, never silently set to zero.

09. SHAPE AND STRUCTURE
Record triaxial radii a,b,c; shape model; differentiation; core, mantle and crust hypotheses; porosity and uncertainty.

10. ORBITAL ELEMENTS
Semi-major axis a [m], eccentricity e, inclination i [rad], longitude of ascending node Omega [rad], argument of periapsis omega [rad], mean anomaly M0 [rad], epoch and reference frame.

11. TWO-BODY APPROXIMATION
mu = G(M_primary + M_satellite).
Mean motion n = sqrt(mu/a^3).
Orbital period T = 2*pi*sqrt(a^3/mu).
Valid for bound Keplerian orbit in two-body approximation; perturbations require richer models.

12. ORBITAL SPEED
For osculating Keplerian elements: v^2 = mu*(2/r - 1/a).
For circular approximation: v = sqrt(mu/r).

13. SURFACE GRAVITY
g approximately G*M/R^2 for a spherical body, evaluated at its surface.
Escape speed v_esc approximately sqrt(2*G*M/R), ignoring rotation and external fields.

14. DENSITY
Mean density rho = M/V.
For a spherical approximation V = (4/3)*pi*R^3.

15. TIDAL FORCES
Differential gravitational acceleration scales approximately as G*M_primary*R_satellite/r^3.
Tidal deformation and dissipation depend on internal rheology, orbital geometry and response parameters.

16. ROCHE LIMIT
For idealised fluid satellite of density rho_s near primary radius R_p and density rho_p:
d_Roche approximately 2.44*R_p*(rho_p/rho_s)^(1/3).
This is an approximation, not a universal disruption boundary.

17. SPIN AND SYNCHRONISATION
Spin period, obliquity, libration, spin-orbit resonance and tidal locking are distinct properties.
Synchronous rotation means mean spin rate matches mean orbital motion; it does not imply absence of rotation.

18. ORBITAL RESONANCE
For near-commensurate mean motions n1/n2 approximately p/q, record integer p,q, resonance angle and dynamical evidence.
Do not infer stable resonance from period ratio alone.

19. ORBITAL EVOLUTION
Tidal migration, eccentricity damping, secular perturbations and orbital decay depend on torque and dissipation models.
Specify model assumptions and timescale uncertainty.

20. FORMATION HYPOTHESES
Giant impact, co-accretion, capture and collisional fragmentation are hypotheses with body-specific evidence; do not assume one mechanism for all moons.

21. GEOLOGICAL FEATURES
Craters, basins, tectonic structures, volcanism, cryovolcanism, regolith, ice shells and subsurface oceans are typed as observed or inferred features.

22. ATMOSPHERIC CLASSIFICATION
Atmosphere may be substantial, tenuous exosphere or absent at observational limits. Record species, pressure, variability and measurement sensitivity.

23. THERMAL BALANCE
Absorbed stellar energy, thermal emission, tidal heating and radiogenic heat contribute to temperature and evolution.
Use emissivity, albedo and geometry in quantitative models.

24. MAGNETIC ENVIRONMENT
Distinguish intrinsic magnetic field, induced magnetic response and ambient magnetospheric field.

25. OBSERVATION TYPES
Imaging, spectroscopy, occultation, radar, altimetry, gravimetry, seismology, in-situ sampling and astrometry.

26. MEASUREMENT MODEL
Measurement = (quantity, value, unit, uncertainty, method, epoch, instrument, calibration, provenance).
No false precision; unit conversions must preserve dimensional consistency.

27. INFERENCE RULES
IF orbits(x,y) AND NaturalSatellite(x) THEN PrimaryBody(y) [contextual type assertion].
IF M>0 AND R>0 AND sphericalApproximation(x) THEN estimateSurfaceGravity(x,G*M/R^2).
IF observedSpinPeriod approximately observedOrbitalPeriod THEN proposeSynchronousRotation(x); verification required.
IF orbitalElementsKnown(x) AND twoBodyValid(x) THEN derivePeriod(x).

28. NON-INFERENCE RULES
Do not infer habitability from subsurface water alone.
Do not infer a global ocean from isolated surface features alone.
Do not infer tidal locking solely from a single observed hemisphere.
Do not infer identical formation history for moons of the same primary.

29. EXAMPLE — EARTH'S MOON
Entity: Earth's Moon; type NaturalSatellite; primary Earth.
Approximate mean radius 1.7374e6 m; mass 7.342e22 kg.
Computed spherical g approximately 1.624 m/s^2 using G=6.67430e-11 SI.
Values illustrative; measurements and reference epochs should be linked for production use.

30. EXAMPLE — PERIOD
Given a=3.844e8 m and mu approximately 4.035e14 m^3/s^2:
T = 2*pi*sqrt(a^3/mu) approximately 2.36e6 s approximately 27.3 days.
This is a sidereal two-body approximation, not the synodic month.

31. VALIDATION
Check units; required types; stable IDs; nonnegative mass/radius; 0<=e<1 for elliptical orbits; coordinate frame; epoch; uncertainty and provenance; source-versus-model separation.

32. SEMANTIC EQUIVALENCE
Natural satellite ~ moon (generic astronomical usage), but Earth's Moon is a specific instance.
Orbital period != rotation period; sidereal period != synodic period.

33. CONFIDENCE
CONFIDENCE = {value:[0,1], basis:[observation|model|literature|hypothesis], evidence_ids, uncertainty_notes}.
Confidence scores must not be invented or presented as measured probabilities without calibration.

34. FLOW HASH
FLOW_HASH = SHA256(canonical_utf8(ontology_payload_excluding_flow_hash)).
Hash algorithm specified; hash value computed by deployment pipeline, not fabricated.

35. UPDATE MODEL
Versioned updates preserve entity IDs, changed-field history, source attribution, review date and rollback capability.

36. AI CONSUMPTION
Input: typed observations, source records and model assumptions.
Process: parse -> validate -> normalise units -> resolve identities -> infer with guards -> report provenance.
Output: structured facts, derived values, uncertainty, constraints and explanation trace.

37. SAFETY AND EPISTEMIC LIMITS
All orbital and geophysical equations require explicit validity conditions. Hypotheses must remain distinguishable from observations.

38. COMPLETENESS CHECK
Sections 01-38 present; all required metadata fields and examples present.

END FLOW ALGEBRA — MOON ONTOLOGY