{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.comet","code":"thing-q3559","url":"https://ver.cy/models/thing/q3559/","name":"comet","alternateNames":["extinct comet","non-periodic comet","elliptical comet","Great Comet","lost comet","sungrazing comet","Manx Comet","long-period comet","aperiodic comet","Marsden sungrazers","Kracht sungrazers","Meyer sungrazers"],"kind":"thing","status":"published","version":"0.2.0-wave.1","language":"en","classifiers":{"family":"Thing Registry","category":"Physical world and living systems","entryKind":"thing","plane":"PHY","domain":["PHY.SPC"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"A small icy astronomical body, either bound to the Solar System or travelling through it from interstellar space, that develops a glowing coma and often tails of gas and dust when close enough to the Sun for its ices to sublimate.","purpose":"Let an agent handle comets by designation, orbit, activity and visibility, and separate them from asteroids and meteors.","scope":{"in":[],"out":[],"boundaries":[]},"distinguishingFeatures":["Icy nucleus that becomes active near the Sun","Coma and tails, unlike asteroids","Periodic and non-periodic orbits","Meteor showers come from comet debris"],"structure":{"bundles":[{"id":"identity","name":"Identity","description":"Which comet.","layers":[{"id":"designation","name":"Designation","description":"MPC designation.","findings":[{"id":"designation-finding","name":"Designation","description":"The designation and name.","questions":[{"text":"What is its designation and name?","kind":"provenance"},{"text":"Is it periodic?","kind":"definition"}]}]},{"id":"discovery","name":"Discovery","description":"Who and when.","findings":[{"id":"discovery-finding","name":"Discovery","description":"Discovery details.","questions":[{"text":"When and by whom was it discovered?","kind":"provenance"},{"text":"Is it a returning comet?","kind":"definition"}]}]}]},{"id":"orbit","name":"Orbit","description":"Path and return.","layers":[{"id":"elements","name":"Elements","description":"Orbital elements.","findings":[{"id":"elements-finding","name":"Orbit","description":"Orbital data.","questions":[{"text":"What are its perihelion date and distance?","kind":"measurement"},{"text":"When will it return, if at all?","kind":"measurement"}]}]},{"id":"approach","name":"Close approach","description":"To Earth.","findings":[{"id":"approach-finding","name":"Approach","description":"Closest approach.","questions":[{"text":"How close does it come to Earth?","kind":"measurement"},{"text":"Is there any risk?","kind":"boundary"}]}]}]},{"id":"activity","name":"Activity","description":"Coma and tails.","layers":[{"id":"brightness","name":"Brightness","description":"Magnitude.","findings":[{"id":"brightness-finding","name":"Brightness","description":"Predicted and observed brightness.","questions":[{"text":"How bright is it expected to be, and how reliable is that?","kind":"measurement"},{"text":"Is it brightening or fading?","kind":"measurement"}]}]},{"id":"composition","name":"Composition","description":"Ices and dust.","findings":[{"id":"composition-finding","name":"Composition","description":"Composition.","questions":[{"text":"What is its composition?","kind":"measurement"},{"text":"How was that measured?","kind":"provenance"}]}]}]},{"id":"observation","name":"Observation","description":"Seeing it.","layers":[{"id":"where","name":"Where to look","description":"Sky position.","findings":[{"id":"where-finding","name":"Visibility","description":"Where and when visible.","questions":[{"text":"Where and when is it visible from a given place?","kind":"action"},{"text":"Is equipment needed?","kind":"definition"}]}]},{"id":"myths","name":"Myths","description":"Doom claims.","findings":[{"id":"myths-finding","name":"Myths","description":"Myths to correct.","questions":[{"text":"Are there false claims about this comet?","kind":"boundary"},{"text":"How should they be corrected?","kind":"action"}]}]}]}]},"agentConduct":{"may":["Report a comet's designation, orbit and brightness from astronomical catalogues.","Help observers plan viewing with times and sky positions."],"mustNot":["Present a comet as an impact threat or omen without evidence.","Give a predicted brightness as certain; comets are notoriously unpredictable.","Misattribute a discovery."],"requiresHuman":["Issuing any public alert about a potential impact."]},"ethics":{"considerations":["Comets have long fuelled panic; false alarms cause real fear.","Discovery credit matters to amateur and professional astronomers."],"affectedParties":["The public","Observers and discoverers"]},"owners":{"steward":"Nobody: a natural body; the international astronomical bodies assign names and designations.","roles":[],"masterSystems":["Minor planet and comet catalogues of the international astronomical bodies"]},"relations":[{"target":"Q193275","type":"parent","note":"registry parent class"},{"target":"astronomical object","type":"related","note":"small body"},{"target":"asteroid","type":"related","note":"no coma"},{"target":"meteor shower","type":"related","note":"debris"},{"target":"star","type":"related","note":"the Sun"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.comet","Wikidata: Q3559 (https://www.wikidata.org/wiki/Q3559)","comet designation: P/ or C/ plus year and letters, or number P/ IAU Minor Planet Center"]},"properties":{"applicability":"required","items":["nucleus diameter: 0.1-60 km","tail length: up to over 1 AU distance"]},"recognition":{"applicability":"required","items":["Fuzzy coma and tails","Designations such as 1P/Halley or C/2020 F3","Meteors are brief streaks, not comets","A fuzzy head (coma) with one or more tails pointing away from the Sun; bright comets are visible to the naked eye."]},"capabilities":{"applicability":"required","items":["discover and designate it","observe it, and predict its visibility","track its orbit","visit it, with spacecraft"]},"hazards":{"applicability":"required","items":["Brightness predictions often wrong","Confusing designations","Sensational doom claims"]},"interfaces":{"applicability":"required","items":["IAU comet naming rules"]},"context":{"applicability":"required","items":["Comets preserve material from the early Solar System and are spectacular sky objects.","short-period (P/) and long-period comets (C/)","sungrazing comets","extinct and lost comets","great comets"]}},"sources":[{"title":"Wikidata item Q3559: comet","url":"https://www.wikidata.org/wiki/Q3559","note":"identity and sense of the item"},{"title":"Wikipedia: Comet","url":"https://en.wikipedia.org/wiki/Comet","note":"general description of the item"}],"openQuestions":["Should comets be instances with MPC designations?","How should brightness uncertainty be communicated?","How should comet and meteor shower links be modelled?"],"resources":{"spec":"/models/things/publications/thing-q3559/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q3559/spec.json"],"providers":["Claude"],"researchStatus":"unreviewed","generatedAt":"2026-09-11T05:28:49Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"filled","interaction.recognition":"filled","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"filled","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-07T10:10:30+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass"},"score":1.0}}