{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.islamic-calendar","code":"thing-q28892","url":"https://ver.cy/models/thing/q28892/","name":"Islamic calendar","alternateNames":["Umm Al-Qura calendar","Tabular Islamic calendar"],"kind":"thing","status":"published","version":"0.2.0-wave.4","language":"en","classifiers":{"family":"Thing Registry","category":"Information and virtual systems","entryKind":"thing","plane":"INF","domain":["INF.KNW"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"The Islamic calendar is a lunar calendar of twelve months in a year of about 354 days, used to date religious observances in Islam such as Ramadan, the Hajj and the two Eids; the registry aliases name computed forms such as the Umm al-Qura and tabular Islamic calendars. Because it is shorter than the solar year, its dates shift earlier each year against the common calendar, so conversions should be checked against current sources. The calendar is treated respectfully.","purpose":"Let an agent explain the Islamic calendar, relay its structure, months and use from reference sources respectfully with conversions checked, describe the computed forms its aliases name, and distinguish it from the solar Gregorian calendar.","scope":{"in":[],"out":[],"boundaries":[]},"distinguishingFeatures":["Lunar","Twelve months","Shorter than the solar year","Dates observances"],"structure":{"bundles":[{"id":"understand","name":"Understand","description":"What the calendar is.","layers":[{"id":"definition","name":"Definition","description":"Definition.","findings":[{"id":"definition-finding","name":"Definition","description":"Definition.","questions":[{"text":"What is the Islamic calendar, and how does it differ from the Gregorian calendar?","kind":"definition"},{"text":"Is the question about a date conversion that needs checking?","kind":"boundary"}]}]},{"id":"forms","name":"Forms","description":"Computed forms.","findings":[{"id":"forms-finding","name":"Forms","description":"Forms.","questions":[{"text":"What are the Umm al-Qura and tabular Islamic calendars?","kind":"definition"},{"text":"Which entry fits the specific form?","kind":"action"}]}]}]},{"id":"structure","name":"Structure","description":"Structure.","layers":[{"id":"months","name":"Months","description":"Months.","findings":[{"id":"months-finding","name":"Months","description":"Months.","questions":[{"text":"What are the twelve months of the Islamic calendar?","kind":"provenance"},{"text":"Which entry fits the specific month?","kind":"action"}]}]},{"id":"lunar","name":"Lunar","description":"Lunar year.","findings":[{"id":"lunar-finding","name":"Lunar","description":"Lunar.","questions":[{"text":"Why is the lunar year shorter than the solar year?","kind":"provenance"},{"text":"Which references are standard?","kind":"provenance"}]}]}]},{"id":"use","name":"Use","description":"Use.","layers":[{"id":"observances","name":"Observances","description":"Observances.","findings":[{"id":"observances-finding","name":"Observances","description":"Observances.","questions":[{"text":"How does the calendar date Ramadan, the Hajj and the Eids?","kind":"provenance"},{"text":"Is the presentation respectful?","kind":"boundary"}]}]},{"id":"sighting","name":"Sighting","description":"Moon sighting.","findings":[{"id":"sighting-finding","name":"Sighting","description":"Sighting.","questions":[{"text":"How do moon sighting and computation set the months?","kind":"provenance"},{"text":"Are conversions checked against current sources?","kind":"boundary"}]}]}]},{"id":"context","name":"Context","description":"Context.","layers":[{"id":"conversion","name":"Conversion","description":"Conversion.","findings":[{"id":"conversion-finding","name":"Conversion","description":"Conversion.","questions":[{"text":"How are Islamic and Gregorian dates converted?","kind":"provenance"},{"text":"Is the information current?","kind":"boundary"}]}]},{"id":"regions","name":"Regions","description":"Regional use.","findings":[{"id":"regions-finding","name":"Regions","description":"Regions.","questions":[{"text":"How does calendar use vary between countries and communities?","kind":"provenance"},{"text":"Is the presentation respectful?","kind":"boundary"}]}]}]}]},"agentConduct":{"may":["Convert dates between the Islamic and common calendars, stating whether a computed or sighting-based form is used.","Explain the lunar year and why observances move through the seasons."],"mustNot":["Fix Islamic dates to set solar dates or present calculated dates as confirmed.","Treat one authority's calendar as binding on every Muslim community.","Treat the calendar or its observances disrespectfully.","Schedule exams or obligations without regard to major observances where accommodation is due."],"requiresHuman":["Announcing the start of Ramadan or Eid to a community."]},"ethics":{"considerations":["Correct dates matter for fasting, pilgrimage and festivals.","Disregarding the calendar in workplaces and schools can exclude Muslims."],"affectedParties":["Muslims","Pilgrims and travellers","Religious authorities"]},"owners":{"steward":"Religious authorities who determine and announce dates for their communities.","roles":[],"masterSystems":[]},"relations":[{"target":"Q17154131","type":"parent","note":"registry parent class"},{"target":"calendar","type":"related","note":"in registry terms"},{"target":"Gregorian calendar","type":"related"},{"target":"solar calendar","type":"related"},{"target":"Islamic observances","type":"related"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.islamic-calendar","Wikidata: Q28892 (https://www.wikidata.org/wiki/Q28892)"]},"properties":{"applicability":"not-applicable","items":["type: lunar calendar note","year: about 354 days note","registry parent: twelve-month calendar note"]},"recognition":{"applicability":"optional","items":["Lunar calendar of twelve Islamic months","Umm al-Qura and tabular Islamic calendars","The Gregorian calendar is solar, so the two drift apart over the years","Not a visible object; a system of lunar months used for dating."]},"capabilities":{"applicability":"required","items":["explain the calendar","relay its structure and months","describe computed forms","distinguish it from solar calendars"]},"hazards":{"applicability":"required","items":["Fixing Islamic dates to solar dates","Confusing computed and observational forms","Non-respectful treatment"]},"interfaces":{"applicability":"required","items":["Calendrical and religious conventions"]},"context":{"applicability":"required","items":["Dating Islamic months and observances.","observational Islamic calendar","Umm al-Qura calendar","tabular Islamic calendar"]}},"sources":[{"title":"Wikidata item Q28892: Islamic calendar","url":"https://www.wikidata.org/wiki/Q28892","note":"identity and sense of the item"},{"title":"Wikipedia: Islamic calendar","url":"https://en.wikipedia.org/wiki/Islamic_calendar","note":"general description of the item"}],"openQuestions":["Should computed forms be separate entries?","How should conversions be verified?","How should months be linked?"],"resources":{"spec":"/models/things/publications/thing-q28892/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q28892/spec.json"],"providers":["Claude"],"researchStatus":"unreviewed","generatedAt":"2026-09-14T03:54:27Z","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":"not-applicable","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 2026-10-06T19:51:58+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass","interaction.properties":"Plane INF: no invented physical properties."},"score":1.0}}