{ "model": { "rank": 6128, "code": "thing-q120200", "model_id": "vr.tr.ephemeris", "name": "ephemeris", "purpose": "Enable an agent to identify an ephemeris, interpret its time-dependent celestial states, assess its fitness for a requested use, and determine whether it may be queried, transformed or superseded.", "family": "Thing Registry", "category": "Information and virtual systems", "status": "research-draft", "kind": "thing", "plane": "INF", "domain": "INF.MED", "industry": "", "version": "", "url": "/models/thing/q120200/", "tier": 2, "score": 62, "payload": { "layer": "wikidata", "aliases": [ "Numerical model of the Solar System" ], "aliasCount": 1, "merged": 1, "knownIn": 62, "facets": null, "markers": [], "lexicalClass": "", "senseRank": null, "alsoRegisteredAs": null, "source": { "dataset": "wikidata", "item": "Q120200", "url": "https://www.wikidata.org/wiki/Q120200", "license": "CC0 1.0" } }, "research": { "vercy": "1.0-draft", "publication": { "status": "research-draft", "adjudicationStatus": "unreviewed", "publishableCanonical": false, "generatedAt": "2026-09-07T11:43:01Z", "providers": [ "Codex", "Grok" ], "missingProviders": [], "pass": 2, "cost": { "grok": { "usd": 0.04828464, "turns": 3, "seconds": 164, "error": null }, "codex": { "seconds": 72.7, "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.3\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a07bab-4991-7582-b9c1-777e5edcec26\n--------\nuser\nYou are drafting a Vercy meta-model for one registered thing. Answer as JSON only, no prose around it.\n\nThing: ephemeris\nRegistry id: vr.tr.ephemeris\nPlane / domain: INF / INF.MED\nRegistry definition: (none recorded)\nNames folded into this entry: (none)\n\nA Ver" } } }, "metaModel": { "id": "THING-Q120200", "registryId": "vr.tr.ephemeris", "name": "ephemeris", "version": "0.1.0-research.1", "entryKind": "thing", "family": "Thing Registry", "domain": [ "INF.MED" ], "status": "research-draft" }, "canonicalUrl": "https://ver.cy/models/thing/q120200/", "model": { "registry_id": "vr.tr.ephemeris", "name": "ephemeris", "purpose": "Enable an agent to identify an ephemeris, interpret its time-dependent celestial states, assess its fitness for a requested use, and determine whether it may be queried, transformed or superseded.", "definition": "An ephemeris is a tabulated or computationally generated representation of the position (and often velocity and clock) of a natural celestial body or artificial satellite as a function of time, expressed in a stated reference frame and time scale.", "scope_statement": "This model owns an ephemeris as an information product representing the position, motion or apparent circumstances of specified celestial targets over time, including the conventions, coverage, derivation and limitations needed to interpret it.", "in_scope": [ "Targets and centres or observers for which celestial states are represented", "Time coverage, time scales and rules for evaluating intermediate epochs", "Coordinate frames, units and geometric or apparent-state conventions", "Derivation, version lineage and supporting observations or dynamical solutions", "Accuracy claims, coverage gaps and conditions governing suitable use" ], "out_of_scope": [ "The celestial bodies themselves and their intrinsic physical properties", "Raw observations and the instruments that acquired them", "Orbit-determination software and dynamical theories as independent systems", "General astronomical catalogues without time-dependent state representations", "Navigation decisions, mission plans and observing schedules that consume an ephemeris" ], "distinguishing_features": [ "It represents celestial state as a function of epoch, rather than merely listing a target's identity or descriptive properties.", "Its values require a specified time convention and spatial reference context to be meaningfully interpreted.", "It supplies time-indexed states or an evaluable representation over a declared interval; an isolated observation does not establish that capability.", "Its primary content is celestial state over time; calendars of events or observing plans may derive from it but serve different purposes.", "An orbital-element set qualifies only if its evaluation conventions and intended coverage establish a usable ephemeris representation; elements alone leave that boundary unresolved." ], "characteristics": [ { "name": "Represented targets", "kind": "relation", "unit_or_values": "Resolvable celestial-body or spacecraft identifiers, including any barycentres", "why_it_matters": "Prevents a state for a system barycentre or similarly named target from being mistaken for the requested body's state." }, { "name": "Reference origin or observer", "kind": "relation", "unit_or_values": "Specified body centre, barycentre, observing site or observer trajectory", "why_it_matters": "Determines what the reported position or direction is relative to." }, { "name": "Represented quantities", "kind": "category", "unit_or_values": "Position, velocity, direction, distance or explicitly named derived circumstances, with units per quantity", "why_it_matters": "Establishes which questions the ephemeris can answer directly." }, { "name": "Time convention", "kind": "category", "unit_or_values": "Named time scale, epoch encoding and conversion dependencies", "why_it_matters": "A numerically identical timestamp can denote a different instant under another convention." }, { "name": "Temporal coverage", "kind": "measurement", "unit_or_values": "Start and end epochs with explicit time scale, endpoint rules and gaps", "why_it_matters": "Distinguishes supported evaluation from extrapolation or missing coverage." }, { "name": "Spatial reference convention", "kind": "category", "unit_or_values": "Named coordinate frame, axes, orientation epoch where applicable and coordinate units", "why_it_matters": "Allows interpretation and comparison without silently mixing reference systems." }, { "name": "Observation correction convention", "kind": "category", "unit_or_values": "Declared geometric or apparent convention and individually specified applied corrections", "why_it_matters": "Prevents differences caused by light propagation or observer effects from being treated as trajectory errors." }, { "name": "Evaluation representation", "kind": "category", "unit_or_values": "Sampled table, coefficient segments or another declared evaluable representation", "why_it_matters": "Determines how an agent obtains a state between stored epochs and which evaluator it needs." }, { "name": "Supported accuracy", "kind": "measurement", "unit_or_values": "Error or uncertainty by quantity, target and interval, with units and statistical meaning; unknown where unsupported", "why_it_matters": "Supports task-specific suitability judgments without equating printed precision with accuracy." }, { "name": "Solution currency", "kind": "state", "unit_or_values": "Current, superseded, withdrawn or unknown within an identified solution lineage", "why_it_matters": "Helps an agent select an appropriate release while preserving reproducibility." } ], "affordances": [ "Evaluate a target's supported state at an epoch within declared coverage.", "Select an ephemeris whose targets, conventions and supported accuracy meet a task's requirements.", "Transform supported states into another reference frame or time convention when the necessary dependencies are available.", "Compare overlapping ephemerides after aligning targets, epochs, origins and correction conventions.", "Derive supported celestial events or observing circumstances while carrying forward relevant limitations.", "Replace a superseded release while retaining the version and evaluation settings used for earlier results." ] }, "sources": [ { "id": "wikipedia-ephemeris", "title": "Ephemeris", "url": "https://en.wikipedia.org/wiki/Ephemeris", "what_it_supports": "Core definition, history from Babylonian tables and zīj through Kepler, modern numerical versus analytical forms, uses in astronomy, navigation, GPS and astrology, and the existence of JPL DE, INPOP and EPM.", "url_status": "live" }, { "id": "usno-circular-5-1", "title": "Ephemerides of the Major Solar System Bodies (USNO Circular 5.1, Chapter 4)", "url": "https://spsweb.fltops.jpl.nasa.gov/portaldataops/mpg/MPG_Docs/Source%20Docs/USNO_Circular_5.1.pdf", "what_it_supports": "Specialist definition of an ephemeris as printed table, file or interrogable software; DE405/LE405 as de facto planetary standard aligned to ICRS; IERS recommendation of DE405; coverage 1600-2201.", "url_status": "blocked" }, { "id": "usno-glossary", "title": "Astronomical Almanac glossary: ephemeris, ephemeris time, barycentric dynamical time", "url": "https://permanent.fdlp.gov/websites/asa.usno.navy.mil/SecM/Glossary.html", "what_it_supports": "Almanac definition of an ephemeris as an ordered tabulation of positions; distinction of astrometric ephemeris; TDB as the IAU time argument of barycentric ephemerides; historical ephemeris time (ET).", "url_status": "blocked" }, { "id": "wikipedia-gps-signals", "title": "GPS signals", "url": "https://en.wikipedia.org/wiki/GPS_signals", "what_it_supports": "Broadcast ephemeris versus almanac in the GPS navigation message; roughly four-hour ephemeris validity versus up to two-week almanac; role in trilateration.", "url_status": "live" }, { "id": "novatel-gnss-eph-alm", "title": "GNSS ephemerides and almanacs", "url": "https://shop.novatel.com/s/contactsupport/article/GNSS-Ephemerides-and-Almanacs", "what_it_supports": "GPS subframes 1-3 as ephemeris and 4-5 as almanac; validity about two hours either side of time of ephemeris; almanac not required for a position fix.", "url_status": "live" }, { "id": "iers-tn36", "title": "IERS Conventions (2010), IERS Technical Note 36", "url": "https://www.iers.org/IERS/EN/Publications/TechnicalNotes/tn36", "what_it_supports": "IERS as the body that standardises frames, time scales and models used when generating and applying high-precision ephemerides.", "url_status": "live" }, { "id": "moiseev-emelyanov-2024", "title": "Ephemeris Theories JPL DE, INPOP, and EPM", "url": "https://doi.org/10.1134/S1063772924700938", "what_it_supports": "The three independently maintained numerical planetary ephemerides (JPL DE, IMCCE INPOP, IAA RAS EPM) as equally usable in practice, with differences from models and data rather than a unique winner.", "url_status": "live" }, { "id": "wikipedia-jpl-de", "title": "Jet Propulsion Laboratory Development Ephemeris", "url": "https://en.wikipedia.org/wiki/Jet_Propulsion_Laboratory_Developmental_Ephemeris", "what_it_supports": "DE series as the operational NASA planetary ephemeris; DE200 then DE405 then DE440 as successive bases of The Astronomical Almanac; DE440/DE441 (2021).", "url_status": "live" }, { "id": "wikipedia-fundamental-ephemeris", "title": "Fundamental ephemeris", "url": "https://en.wikipedia.org/wiki/Fundamental_ephemeris", "what_it_supports": "Distinction between a fundamental dynamical ephemeris and the apparent ephemerides, phenomena and orbital elements derived from it for almanacs.", "url_status": "live" }, { "id": "imcce-ephemerides", "title": "Les éphémérides", "url": "https://media4.obspm.fr/public/ressources_lu/pages_ephemerides/impression.html", "what_it_supports": "French specialist account of an ephemeris as a representation of motion; vernacular versus astronomical sense of éphéméride; tabulated interval set by how fast the coordinates change.", "url_status": "live" } ], "structure": { "bundles": [ { "id": "celestial-state-identity", "name": "Celestial state identity", "description": "Establishes exactly whose state is represented and relative to what.", "rationale": "An ephemeris can be numerically valid yet answer the wrong question if its target, centre or observer is misidentified.", "layers": [ { "id": "target-resolution", "name": "Target resolution", "description": "Resolves target identities and distinguishes bodies from system reference points.", "findings": [ { "id": "target-and-system-membership", "name": "Target and system membership", "description": "Record authoritative target identifiers and whether each target denotes an individual body, spacecraft or barycentre.", "questions": [ { "text": "Which identifiers resolve the represented targets, and does each denote a body centre, spacecraft or system barycentre?", "kind": "definition", "id": "target-and-system-membership-q01" }, { "text": "Which requested targets could be confused with these identifiers but are not represented?", "kind": "boundary", "id": "target-and-system-membership-q02" } ] } ] }, { "id": "relative-state-context", "name": "Relative state context", "description": "Identifies origins, observers and the quantities represented relative to them.", "findings": [ { "id": "origin-observer-and-quantities", "name": "Origin, observer and quantities", "description": "Record the state origin or observer, its defining information, and the available state quantities.", "questions": [ { "text": "Relative to which centre or observer are position, velocity, direction and distance expressed?", "kind": "definition", "id": "origin-observer-and-quantities-q01" }, { "text": "If an observer-specific result is requested, which site coordinates or observer trajectory must be supplied?", "kind": "action", "id": "origin-observer-and-quantities-q02" } ] } ] } ] }, { "id": "epoch-coverage-and-evaluation", "name": "Epoch coverage and evaluation", "description": "Defines when states are available and how they are evaluated.", "rationale": "An ephemeris must support a defensible mapping from a requested instant to a state, including between stored samples.", "layers": [ { "id": "time-interpretation", "name": "Time interpretation", "description": "Makes epoch encodings, time scales and conversion requirements explicit.", "findings": [ { "id": "epoch-semantics", "name": "Epoch semantics", "description": "Record how epochs identify instants and whether reported times refer to observation, emission or another declared event.", "questions": [ { "text": "Which time scale and encoding define an input epoch, and what instant does an output timestamp denote?", "kind": "definition", "id": "epoch-semantics-q01" }, { "text": "Which conversion data or conventions are required to interpret a user's requested time correctly?", "kind": "action", "id": "epoch-semantics-q02" } ] } ] }, { "id": "coverage-and-interpolation", "name": "Coverage and interpolation", "description": "Describes supported intervals, segmentation and evaluation between stored epochs.", "findings": [ { "id": "supported-evaluation-domain", "name": "Supported evaluation domain", "description": "Record coverage per target and quantity, gaps, evaluator requirements and the treatment of interval boundaries.", "questions": [ { "text": "What intervals are supported for each target and quantity, including gaps and endpoint inclusion?", "kind": "boundary", "id": "supported-evaluation-domain-q01" }, { "text": "How are intermediate epochs evaluated, and what response is required when a request would extrapolate beyond coverage?", "kind": "action", "id": "supported-evaluation-domain-q02" } ] } ] } ] }, { "id": "spatial-and-apparent-conventions", "name": "Spatial and apparent conventions", "description": "Defines the spatial meaning of states and the corrections applied to observable quantities.", "rationale": "Ephemerides cannot be safely compared or combined until their frames, units and observation conventions are compatible.", "layers": [ { "id": "frame-and-coordinate-semantics", "name": "Frame and coordinate semantics", "description": "Identifies coordinate systems and the dependencies needed to transform them.", "findings": [ { "id": "reference-frame-definition", "name": "Reference frame definition", "description": "Record frame identity, coordinate representation, units and any time-dependent orientation conventions.", "questions": [ { "text": "Which frame, axes, coordinate representation and units define each reported quantity?", "kind": "definition", "id": "reference-frame-definition-q01" }, { "text": "Which orientation data and epoch conventions are necessary to transform these states into the requested frame?", "kind": "action", "id": "reference-frame-definition-q02" } ] } ] }, { "id": "observation-corrections", "name": "Observation corrections", "description": "Separates geometric states from quantities adjusted for observation circumstances.", "findings": [ { "id": "correction-chain", "name": "Correction chain", "description": "Record the meaning of apparent quantities and the individual corrections already applied.", "questions": [ { "text": "Are the quantities geometric or apparent, and which light-time, aberration, deflection or atmospheric corrections are declared?", "kind": "definition", "id": "correction-chain-q01" }, { "text": "Which corrections must an agent apply or avoid applying again for the intended observer and use?", "kind": "action", "id": "correction-chain-q02" } ] } ] } ] }, { "id": "solution-lineage-and-reproducibility", "name": "Solution lineage and reproducibility", "description": "Connects an ephemeris release to its underlying solution and reproducible evaluation context.", "rationale": "Updated observations, fitted solutions or evaluation dependencies can change returned states even when target names remain the same.", "layers": [ { "id": "state-derivation", "name": "State derivation", "description": "Identifies the observations, fitted solution or upstream ephemeris from which states were produced.", "findings": [ { "id": "underlying-solution", "name": "Underlying solution", "description": "Record documented derivation and distinguish fitted, predicted and transformed content where the provider supports that distinction.", "questions": [ { "text": "Which named solution, observations or upstream ephemeris produced these states, and where is that derivation documented?", "kind": "provenance", "id": "underlying-solution-q01" }, { "text": "Which intervals or targets have different derivation assumptions or prediction status?", "kind": "boundary", "id": "underlying-solution-q02" } ] } ] }, { "id": "release-and-evaluator-lineage", "name": "Release and evaluator lineage", "description": "Identifies the precise release and dependencies required to reproduce a state.", "findings": [ { "id": "reproducible-state-request", "name": "Reproducible state request", "description": "Record release identity, evaluator and dependency versions, query settings and any supersession notice.", "questions": [ { "text": "Which artifact or service release, evaluator, dependencies and query settings identify the result reproducibly?", "kind": "provenance", "id": "reproducible-state-request-q01" }, { "text": "Has the provider superseded or withdrawn this solution, and which uses require migration rather than historical reproduction?", "kind": "action", "id": "reproducible-state-request-q02" } ] } ] } ] }, { "id": "accuracy-and-use-boundaries", "name": "Accuracy and use boundaries", "description": "Relates supported error claims and evaluation limitations to a proposed use.", "rationale": "Temporal coverage and successful evaluation alone do not establish suitability for navigation, event timing or pointing.", "layers": [ { "id": "state-quality-evidence", "name": "State quality evidence", "description": "Distinguishes numerical precision, interpolation error and uncertainty in the underlying celestial solution.", "findings": [ { "id": "qualified-error-claims", "name": "Qualified error claims", "description": "Record accuracy evidence with its target, interval, quantity, reference and statistical interpretation.", "questions": [ { "text": "What error bounds, uncertainty estimates or validation residuals are documented, with which units and statistical meaning?", "kind": "measurement", "id": "qualified-error-claims-q01" }, { "text": "Which targets, intervals and quantities do those claims cover, and do they include interpolation and transformation effects?", "kind": "boundary", "id": "qualified-error-claims-q02" } ] } ] }, { "id": "task-specific-admissibility", "name": "Task-specific admissibility", "description": "Determines whether a requested computation is supported by the ephemeris and its evidence.", "findings": [ { "id": "request-fitness-and-disposition", "name": "Request fitness and disposition", "description": "Record the requested tolerance and decide whether to proceed, qualify the result or obtain another ephemeris.", "questions": [ { "text": "What position, angular or timing tolerance does the proposed use require, and can the available evidence support it?", "kind": "measurement", "id": "request-fitness-and-disposition-q01" }, { "text": "When coverage, conventions or accuracy evidence are insufficient, should the agent reject the request, return an explicitly qualified result or select another ephemeris?", "kind": "action", "id": "request-fitness-and-disposition-q02" } ] } ] } ] }, { "id": "evidence-and-external-alignment", "name": "Evidence and external alignment", "description": "What the world already says about this thing, gathered so the model can be checked against it.", "rationale": "A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.", "layers": [ { "id": "reported-evidence", "name": "Reported evidence", "description": "Findings from the breadth pass, kept separate from the structural claims.", "findings": [ { "id": "evidence-kinds", "name": "Kinds and varieties", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ "Fundamental (dynamical) planetary ephemeris - a numerically integrated, self-consistent solar-system solution (JPL DE, IMCCE INPOP, IAA RAS EPM) from which other products are derived.", "Analytical series ephemeris - closed-form trigonometric expansions of coordinates (VSOP, Éphéméride Lunaire Parisienne).", "Apparent or astrometric observational ephemeris - right ascension, declination and related quantities for a stated equinox, as used by observers and printed almanacs.", "GNSS broadcast ephemeris - satellite-specific orbital and clock parameters in the real-time navigation message, valid only for a few hours.", "Precise GNSS orbit and clock product - post-processed or real-time precise ephemerides (for example IGS), used instead of the broadcast message.", "Celestial-navigation almanac ephemeris - tabulated Sun, Moon, planet and star data in the Nautical Almanac and Air Almanac.", "Operational spacecraft/satellite ephemeris - binary state files or propagator products (SPICE SPK, mission kernels) used for pointing and navigation.", "Astrological ephemeris - daily tropical or sidereal longitudes of planets and nodes for chart calculation." ], "questions": [ { "id": "evidence-kinds-q01", "text": "Which of these kinds and varieties hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-identifiers", "name": "Identifiers and schemes", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ { "scheme": "Wikidata item", "value_or_pattern": "Q134286", "note": "Concept item for ephemeris as a table or model of celestial positions over time." }, { "scheme": "JPL Development Ephemeris designation", "value_or_pattern": "DE{nnn} or DE{nnn}/LE{nnn} (for example DE440, DE441, DE405/LE405)", "note": "NASA JPL labels for successive numerically integrated planetary and lunar ephemerides." }, { "scheme": "IMCCE planetary ephemeris designation", "value_or_pattern": "INPOP{version} (for example INPOP10e, INPOP17a)", "note": "Paris Observatory / IMCCE numerical planetary ephemeris series." }, { "scheme": "IAA RAS planetary ephemeris designation", "value_or_pattern": "EPM{year or version}", "note": "Institute of Applied Astronomy, Russian Academy of Sciences, Ephemerides of Planets and the Moon." }, { "scheme": "GPS navigation-message keys", "value_or_pattern": "IODE (Issue of Data, Ephemeris) with toe (time of ephemeris) and GPS week", "note": "Identify a specific broadcast-ephemeris fit on a given satellite; mismatch means the set must not be used." }, { "scheme": "RINEX navigation file", "value_or_pattern": "RINEX navigation/ephemeris files (historically .yyN; mixed GNSS NAV)", "note": "International GNSS Service exchange format for broadcast ephemerides recovered from receivers." } ], "questions": [ { "id": "evidence-identifiers-q01", "text": "Which of these identifiers and schemes hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-standards-and-regulation", "name": "Standards and regulation", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ "IERS Conventions (2010), Technical Note 36 - International Earth Rotation and Reference Systems Service: conventional celestial and terrestrial frames, time scales and relativistic models used with high-precision ephemerides.", "IAU resolutions on time scales and the International Celestial Reference System - International Astronomical Union: TDB as independent argument of barycentric ephemerides; ICRS/ICRF as the reference frame for modern planetary ephemerides.", "IS-GPS-200 (Navstar GPS Space Segment/Navigation User Interfaces) - U.S. Space Force / GPS directorate: binary layout, fit interval and user algorithms for the GPS broadcast ephemeris (and the distinct almanac).", "Corresponding GNSS interface control documents - European Union (Galileo OS SIS ICD), Russian Federation (GLONASS ICD), China (BeiDou ICD), Japan (QZSS): each constellation's broadcast-ephemeris message.", "The Astronomical Almanac / former American Ephemeris and Nautical Almanac conventions - U.S. Naval Observatory with HM Nautical Almanac Office (UK): official apparent ephemerides of Sun, Moon and planets; based on JPL DE200 (1984-2002), DE405 (from 2003), DE440 (by 2024).", "IERS recommendation of JPL DE405 (IERS Conventions 2003 era) - IERS: DE405 as a recommended fundamental ephemeris, without an IAU resolution adopting any single DE.", "RINEX (Receiver Independent Exchange Format) - International GNSS Service: standard files for exchanging recovered broadcast ephemerides.", "NASA NAIF SPICE SPK - NASA Navigation and Ancillary Information Facility: operational kernel format for spacecraft and natural-body ephemerides." ], "questions": [ { "id": "evidence-standards-and-regulation-q01", "text": "Which of these standards and regulation hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-real-world-use", "name": "Real-world use", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ "A GNSS receiver decodes each satellite's broadcast ephemeris from subframes 1-3 and computes that satellite's Earth-fixed position and clock at signal time in order to form a position-velocity-time solution.", "Mission navigators and astronomers query JPL HORIZONS or load a DE440/SPK kernel to obtain barycentric states of planets, the Moon and many small bodies.", "The Astronomical Almanac, Connaissance des Temps, Nautical Almanac and Air Almanac publish apparent places used for telescope scheduling, reduction of observations, and backup celestial navigation.", "Spacecraft trajectory design and in-flight navigation are integrated against a chosen fundamental ephemeris (DE, INPOP or EPM); the three are treated as comparably valid.", "Surveyors and geodesists apply precise IGS orbit/clock products rather than broadcast ephemerides when millimetre-to-centimetre positioning is required.", "Astrologers still read daily tropical longitudes from printed or Swiss-Ephemeris-class tables, even though chart software has replaced most hand calculation.", "Printed tables remain a fall-back when electronic computation is unavailable, which is why nautical and astronomical almanacs are still issued." ], "questions": [ { "id": "evidence-real-world-use-q01", "text": "Which of these real-world use hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-measurements", "name": "Typical measurements", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ { "quantity": "GNSS broadcast-ephemeris fit / validity interval", "typical_range": "about 2 hours before and after time of ephemeris (toe); GPS ephemeris commonly treated as valid ~4 hours, versus almanac days to ~90 days", "unit": "hour" }, { "quantity": "Broadcast GNSS orbit accuracy (modern GPS)", "typical_range": "roughly 1 to 2", "unit": "metre" }, { "quantity": "Broadcast GNSS satellite-clock error", "typical_range": "a few", "unit": "nanosecond" }, { "quantity": "Fundamental planetary-ephemeris time span (examples)", "typical_range": "DE405 about 1600-2201; DE440 file linux_p1550p2650.440 about 1550-2650; DE441 longer for historical work", "unit": "year (Julian/Gregorian civil)" }, { "quantity": "Independent time argument of a barycentric planetary ephemeris", "typical_range": "TDB or equivalent IAU coordinate time along the integration; historical products used ephemeris time (ET)", "unit": "second (SI) on the stated scale" }, { "quantity": "Observer-frame sky position", "typical_range": "right ascension 0-24; declination −90 to +90, plus distance when given", "unit": "hour and degree (plus astronomical unit or kilometre)" }, { "quantity": "Tabulation step of a printed ephemeris", "typical_range": "hours to a month, set by how fast the coordinates change (Moon finer than outer planets)", "unit": "day" } ], "questions": [ { "id": "evidence-measurements-q01", "text": "Which of these typical measurements hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-failure-modes-and-hazards", "name": "Failure modes and hazards", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ "Using a GNSS broadcast ephemeris outside its fit interval, or mixing records with mismatched IODE/toe, yields metre-to-worse satellite positions and a false PVT fix.", "Treating the coarse almanac as an ephemeris in the navigation solution produces kilometre-scale satellite-position error.", "Evaluating a planetary ephemeris on the wrong time scale (UT1 or UTC instead of TT/TDB, or GPS time without leap-second handling) shifts the body by an amount that grows with its angular rate - critical for the Moon and for spacecraft.", "Applying a geometric barycentric state as an apparent geocentric or topocentric place, or using the wrong equinox (B1950, J2000, of-date), mispoints telescopes and misreduces observations.", "For the Moon and near-Earth asteroids, a geocentric ephemeris used as if it were topocentric is geometrically wrong by a large fraction of a degree.", "Secular error from poorly known asteroid masses limits how far a planetary ephemeris can be trusted, which is why DE/INPOP/EPM are re-fit as new data arrive.", "Interpolating a printed table whose step is too coarse relative to the motion introduces errors larger than the underlying theory.", "An unhealthy satellite flag or stale upload left in the broadcast message can be used by a receiver that does not check health, corrupting the navigation solution.", "Celestial-navigation position-line error follows directly from a wrong almanac year, assumed-position interpolation mistake, or outdated v correction." ], "questions": [ { "id": "evidence-failure-modes-and-hazards-q01", "text": "Which of these failure modes and hazards hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-regional-variation", "name": "Regional variation", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ "English-language official products are the joint US/UK Astronomical Almanac and the Nautical/Air Almanacs; the underlying dynamical ephemeris has long been a JPL DE.", "In French, éphémérides is the technical term (IMCCE, Connaissance des Temps, INPOP), while éphéméride in ordinary usage also means the day's notable events, unrelated to celestial positions.", "Russia maintains an independent numerical theory (EPM at IAA RAS) and a distinct GLONASS broadcast-ephemeris ICD; France maintains INPOP in parallel with JPL DE.", "Historical Islamic practice named the same kind of table a zīj; Chinese official tables and the Mayan Dresden Codex are independent tabular traditions.", "Each GNSS operator (GPS, Galileo, GLONASS, BeiDou, QZSS, NavIC) broadcasts ephemerides in its own message layout and time scale, even though RINEX is used to archive them in a common form.", "Astrology still publishes national 'ephemerides' (for example Raphael's, Swiss Ephemeris) whose longitudes are not the ICRS apparent places of the Astronomical Almanac." ], "questions": [ { "id": "evidence-regional-variation-q01", "text": "Which of these regional variation hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-neighbours", "name": "Neighbouring kinds and how to tell them apart", "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.", "evidence": [ { "name": "GNSS almanac", "difference": "The almanac is a coarse, constellation-wide orbit and health set valid for days to months and used only to acquire satellites; the ephemeris is satellite-specific, metre-class, and required for the PVT solution, with a validity of a few hours." }, { "name": "Orbital elements (Keplerian or osculating)", "difference": "Six (or a few more) parameters describe an orbit at an epoch; an ephemeris is the time series of states, or a fit that can be evaluated as a function of time, generated from such a theory plus perturbations." }, { "name": "Two-line element set (TLE)", "difference": "A TLE is a mean-element card for the SGP4/SDP4 propagator, typically kilometre-class for many objects; a high-precision ephemeris is a numerically integrated or GNSS-fitted state in a stated inertial or ECEF frame." }, { "name": "Ephemeris time (ET)", "difference": "ET is a historical uniform time scale (IAU 1952, used as the independent argument of ephemerides until the 1970s-84) and is not the table or model itself; modern arguments are TDB/TCB/TT." }, { "name": "Star catalogue", "difference": "A catalogue gives mean places of stars (with proper motion and parallax) at a catalogue epoch; an ephemeris gives the changing position of a solar-system body or satellite. An astrometric ephemeris is deliberately made comparable to an updated catalogue place." }, { "name": "Nautical or astronomical almanac (the book)", "difference": "The almanac is a publication that contains ephemerides plus phenomena, sight-reduction data and explanations; the ephemeris is the position-versus-time content inside it." }, { "name": "Apparent place versus geometric barycentric state", "difference": "A fundamental ephemeris yields geometric states in the solar-system barycentric frame; an apparent ephemeris has been reduced for light-time, aberration, precession-nutation and the observer's location." }, { "name": "Ephemera", "difference": "Ephemera are transient printed items collected as objects; the shared Greek root (daily) is etymological only and does not make a handbill an astronomical ephemeris." } ], "questions": [ { "id": "evidence-neighbours-q01", "text": "Which of these neighbouring kinds and how to tell them apart hold for the sense of ephemeris this model covers, and on what evidence?", "kind": "provenance" } ] } ] } ] } ] }, "openQuestions": [ "Does this registry entry intend astronomical ephemerides only, or also historical calendrical publications carrying the same name?", "Should standalone orbital-element sets with a specified propagator be owned here or linked from a neighbouring orbital-solution model?", "Does this entry include orientation ephemerides, or should body orientation remain a neighbouring model linked to positional ephemerides?", "Should an ephemeris delivered through a live service be represented as a distinct information product from each reproducible query result?", "Which provider documentation and representative formats should establish the supported vocabulary for accuracy, correction conventions and solution status?" ], "statistics": { "bundles": 6, "layers": 11, "findings": 18, "questions": 28 } }, "draft": { "generator": "vr.draft.v3", "status": "draft-generated", "researched": false, "archetype": "work, medium or creative form", "method": "Written from the archetype playbook - what this kind of thing needs beyond identity and provenance - and from the structure that recurred across 6,333 models already researched by two engines. Applied to this entry by rule. No source was read for this thing and no claim here is researched. This entry carries no facets of its own, so they were inferred from its domain - a guess about a whole domain applied to one thing.", "facetsInferred": true, "nextPass": "A researcher replaces this draft with a sourced specification. Treat every sentence below as a proposal to argue with.", "purpose": "Give an agent a durable, checkable way to recognise a ephemeris, record what state it is in, and decide what may be done with it.", "whatItIs": "Enable an agent to identify an ephemeris, interpret its time-dependent celestial states, assess its fitness for a requested use, and determine whether it may be queried, transformed or superseded.", "characteristics": { "substance": "information", "origin": "conceptual", "agency": "inert" }, "whatYouCanDoWithIt": [ "read and interpreted", "observed and measured" ], "distinguishingFeatures": [ "Names folded into this entry, which a task may need to split apart again: Numerical model of the Solar System.", "1 finer distinctions are held as aliases rather than separate entries, because telling them apart needs a task that asks for it.", "Described in 62 Wikipedia languages, which is a measure of how widely the thing is known, not of how important it is." ], "openQuestionsForResearch": [ "Which of the bundles below does a real task actually need, and which are ceremony?", "What does this thing have that the facets do not capture at all?", "Which neighbouring kind is most often confused with a ephemeris, and on what evidence are they told apart?" ], "whatItIsMadeOf": "content that has to be carried by something else", "physicalCharacter": [ "Does nothing on its own; everything it does, something else did to it.", "These come from the domain this entry sits in rather than from the entry itself, so treat them as a first guess about the whole domain applied to one thing." ], "whatCanBeDoneWithIt": [ "read it and act on what it says", "observe it, measure it, record its state" ], "howItIsRecognised": [ "What is seen is a copy or a performance, not the work. Recognising the work means recognising the content through whatever is carrying it." ], "relatedModels": [ { "relation": "covers", "note": "Finer kinds folded into this entry because telling them apart needs a task that asks for it. Each is a model waiting to be split out when one does.", "targets": [ "Numerical model of the Solar System" ] } ], "standing": "Described in 62 Wikipedia languages, which measures how widely it is written about rather than how important or how common it is. 1 finer distinctions are held inside this entry as names rather than as separate models.", "structure": { "bundles": [ { "id": "identity-and-classification", "name": "Identity, naming and classification", "description": "How an agent tells one ephemeris from another, and a ephemeris from things that resemble it.", "rationale": "Recognition comes before every other claim. Without stable identity nothing else in the model can be trusted to be about the same thing twice.", "layers": [ { "id": "naming-and-identifiers", "name": "Names and identifiers", "description": "The names this thing goes by and the identifiers that survive translation and time.", "findings": [ { "id": "preferred-name-and-aliases", "name": "Preferred name, aliases and local names", "description": "Which name to use, which names mean the same thing, and which merely sound similar.", "questions": [ { "id": "preferred-name-and-aliases-q01", "text": "What identifies and describes the name of a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "preferred-name-and-aliases-q02", "text": "Who or what asserted this about the name of a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "preferred-name-and-aliases-q03", "text": "What may an agent decide or do once the name of a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "stable-identifiers", "name": "Stable identifiers and external keys", "description": "Identifiers that keep pointing at this kind of thing across systems and languages.", "questions": [ { "id": "stable-identifiers-q01", "text": "What identifies and describes an identifier for a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stable-identifiers-q02", "text": "Who or what asserted this about an identifier for a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stable-identifiers-q03", "text": "What may an agent decide or do once an identifier for a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "classification-and-granularity", "name": "Classification and granularity", "description": "Where a ephemeris sits among kinds, and how finely a task needs to cut it.", "findings": [ { "id": "kind-and-parents", "name": "Kind, parents and neighbouring kinds", "description": "The classes this thing belongs to and the ones it is next to.", "questions": [ { "id": "kind-and-parents-q01", "text": "What identifies and describes the kind of a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "kind-and-parents-q02", "text": "Who or what asserted this about the kind of a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "kind-and-parents-q03", "text": "What may an agent decide or do once the kind of a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "distinguishing-features", "name": "Distinguishing features", "description": "What separates a ephemeris from the things most often confused with it.", "questions": [ { "id": "distinguishing-features-q01", "text": "What identifies and describes what distinguishes a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "distinguishing-features-q02", "text": "Who or what asserted this about what distinguishes a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "distinguishing-features-q03", "text": "What may an agent decide or do once what distinguishes a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "state-and-lifecycle", "name": "State and lifecycle", "description": "The states a ephemeris passes through and the events that move it between them.", "rationale": "Most decisions about a thing depend on what state it is in now, which is a claim with a time on it, not a property.", "layers": [ { "id": "lifecycle-stages", "name": "Lifecycle stages", "description": "From coming into existence to ceasing to be one of these.", "findings": [ { "id": "stages-and-transitions", "name": "Stages and transitions", "description": "The stages worth naming and what moves a ephemeris between them.", "questions": [ { "id": "stages-and-transitions-q01", "text": "What identifies and describes the lifecycle of a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stages-and-transitions-q02", "text": "Who or what asserted this about the lifecycle of a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stages-and-transitions-q03", "text": "What may an agent decide or do once the lifecycle of a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "observations-and-status", "name": "Observations and current status", "description": "What is observed about a ephemeris, how often and by whom.", "findings": [ { "id": "observation-record", "name": "Observation record", "description": "How an observation of a ephemeris is recorded so that it can be superseded rather than overwritten.", "questions": [ { "id": "observation-record-q01", "text": "What identifies and describes an observation of a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "observation-record-q02", "text": "Who or what asserted this about an observation of a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "observation-record-q03", "text": "What may an agent decide or do once an observation of a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "content-and-access", "name": "Content, encoding and access", "description": "What a ephemeris says, how it is encoded and who may read it.", "rationale": "An informational thing carries content that can be copied, versioned and withheld, none of which its physical carrier explains.", "layers": [ { "id": "content-and-encoding", "name": "Content and encoding", "description": "The content itself, its format and its language.", "findings": [ { "id": "content-and-format", "name": "Content, format and language", "description": "What a ephemeris contains and in what form it is held.", "questions": [ { "id": "content-and-format-q01", "text": "What identifies and describes the content of a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "content-and-format-q02", "text": "Who or what asserted this about the content of a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "content-and-format-q03", "text": "What may an agent decide or do once the content of a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "access-and-rights", "name": "Access, rights and retention", "description": "Who may read, copy or change it, and for how long it is kept.", "findings": [ { "id": "access-rules", "name": "Access rules and retention", "description": "The permissions attached to a ephemeris and the period it survives.", "questions": [ { "id": "access-rules-q01", "text": "What identifies and describes access to a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "access-rules-q02", "text": "Who or what asserted this about access to a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "access-rules-q03", "text": "What may an agent decide or do once access to a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "work-and-manifestation", "name": "Work, version and copy", "description": "Which level of ephemeris a statement is about.", "rationale": "The work, the edition, the file and the copy in hand are four things; rights and content attach to different ones.", "layers": [ { "id": "levels", "name": "Levels of the thing", "description": "Work, expression, manifestation and item, in plain terms.", "findings": [ { "id": "level-rules", "name": "What belongs at each level", "description": "Which facts hold for the work and which only for one copy.", "questions": [ { "id": "level-rules-q01", "text": "For ephemeris, which facts belong to the work itself, which to a version, and which to a single copy?", "kind": "boundary" }, { "id": "level-rules-q02", "text": "What identifier exists at each level, and which one is being cited?", "kind": "definition" } ] } ] }, { "id": "versions", "name": "Versions, editions and variants", "description": "How versions differ and which is canonical to whom.", "findings": [ { "id": "version-record", "name": "Versions and canonicity", "description": "Differences that matter and who calls one authoritative.", "questions": [ { "id": "version-record-q01", "text": "Which versions or editions of ephemeris exist, and how do they differ substantively?", "kind": "definition" }, { "id": "version-record-q02", "text": "Who treats which version as authoritative, and for what purpose?", "kind": "provenance" } ] } ] } ] }, { "id": "authorship-and-rights", "name": "Authorship, rights and permitted use", "description": "Who made ephemeris and what may be done with it.", "rationale": "Rights are jurisdictional, time-limited and attached to a level, and an agent that ignores that will copy what it may not.", "layers": [ { "id": "authorship", "name": "Authorship and contribution", "description": "Who contributed what, and in what capacity.", "findings": [ { "id": "contribution-record", "name": "Contributors and roles", "description": "The people and bodies behind it, with their roles.", "questions": [ { "id": "contribution-record-q01", "text": "Who authored or contributed to ephemeris, in what roles, and how is that attested?", "kind": "provenance" }, { "id": "contribution-record-q02", "text": "Where authorship is disputed or anonymous, what is recorded instead?", "kind": "boundary" } ] } ] }, { "id": "rights", "name": "Rights and permissions", "description": "Which rights subsist, where, until when, and what they permit.", "findings": [ { "id": "rights-record", "name": "Rights, term and permitted acts", "description": "The regime in force and what it allows.", "questions": [ { "id": "rights-record-q01", "text": "What rights subsist in ephemeris, in which jurisdictions, and until when?", "kind": "definition" }, { "id": "rights-record-q02", "text": "Which acts are permitted without further permission, and which must an agent refuse?", "kind": "action" } ] } ] } ] }, { "id": "provenance-and-evidence", "name": "Provenance, evidence and time", "description": "Where every claim about a ephemeris came from and when it held.", "rationale": "A claim without a source and a time cannot be superseded, only overwritten, and an agent that overwrites loses the ability to explain itself.", "layers": [ { "id": "source-and-authority", "name": "Source and authority", "description": "Who said it, on what evidence, and how strongly.", "findings": [ { "id": "claim-provenance", "name": "Claim provenance and confidence", "description": "The authority behind each claim about a ephemeris and how confident it is.", "questions": [ { "id": "claim-provenance-q01", "text": "What identifies and describes a claim about a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "claim-provenance-q02", "text": "Who or what asserted this about a claim about a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "claim-provenance-q03", "text": "What may an agent decide or do once a claim about a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "time-and-versions", "name": "Time, versions and supersession", "description": "When a claim was true, when it was learnt, and what replaced it.", "findings": [ { "id": "validity-and-supersession", "name": "Validity period and supersession", "description": "How an old claim about a ephemeris is retired without being erased.", "questions": [ { "id": "validity-and-supersession-q01", "text": "What identifies and describes the validity of a claim about a ephemeris, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "validity-and-supersession-q02", "text": "Who or what asserted this about the validity of a claim about a ephemeris, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "validity-and-supersession-q03", "text": "What may an agent decide or do once the validity of a claim about a ephemeris is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] } ] }, "statistics": { "bundles": 6, "layers": 12, "findings": 14, "questions": 38 } } } }