June 21
Let an agent handle June 21 as a calendar date with weekday computation, observances attributed to their traditions and sourced events.
Bundle → Layer → Finding → Questions Filled
4 bundles · 8 layers · 8 findings · 16 questions
Date Calendar facts.
Weekday
Computation.
Weekday
Weekday.
- On which weekday does June 21 fall in this year? measurement
- Is it a leap year? boundary
Calendar
Julian or Gregorian.
Calendar
Calendar system.
- Is the Julian or Gregorian calendar meant? boundary
- What is the equivalent date in the other calendar? measurement
Observances Holidays.
Holiday
Public holiday.
Holiday
Holiday status.
- Is June 21 a public holiday or observance here? provenance
- Which tradition or law sets it? provenance
Attribution
Traditions.
Attribution
Attributed observances.
- Which countries or communities observe something on this date, according to them? provenance
- Is the observance attributed rather than assumed? boundary
History Past events.
Events
On this day.
Events
Historical events.
- Which notable events happened on June 21, according to reliable sources? provenance
- Are dates given in the same calendar? boundary
Anniversaries
Recurring.
Anniversaries
Anniversaries.
- Which anniversaries fall on this date this year? provenance
- Which are round numbers? measurement
Planning Scheduling.
Countdown
Days until.
Countdown
Countdown.
- How many days until the next June 21? measurement
- From which date? definition
Work
Working day.
Work
Working day.
- Is it a working day for this organisation? provenance
- Do deadlines move? boundary
Classifiers Filled
- Family
- Thing Registry
- Category
- Cross-cutting context
- Entry kind
- thing
- Plane
- XCT
- Domain
- XCT.TME
What it is Filled
June 21, day 172 (day 173 in leap years) of the year in the Gregorian calendar, with 193 days remaining in both common and leap years. June 21 is the date of the June solstice in most years, marking midsummer in the northern hemisphere and midwinter in the southern; the United Nations observes the International Day of Yoga on this date, and observances vary by country and tradition.
Why it exists Filled
Let an agent handle June 21 as a calendar date with weekday computation, observances attributed to their traditions and sourced events.
Distinguishing features Filled
- The twenty-first day of June
- Weekday varies by year
- Observances vary by place
- Julian and Gregorian dates differ by 13 days in this era
What robots and AI may and may not do Filled
Must not
- Claim the solstice always falls on June 21.
- Disrespect midsummer festivals or sacred sites observed on this date.
- Present a person's birthday on June 21 as public information.
Only with a human decision
- Scheduling access to sacred sites on the solstice.
May
- State that June 21 is day 172 of a common year and usually the June solstice.
- Check the exact solstice time for a year before reporting it.
Moral aspects Filled
- Solstice observances matter to many communities and faiths.
- Crowds at solstice sites can endanger heritage.
Who is affected
- Communities with solstice observances
- People born on the date
Owners Filled
Steward
Nobody: held in common; the calendar convention is international.
Links to other meta-models Filled
parent
- Q11187254 - registry parent class
related
- June - month
- June 20 - date
- calendar date - category
- ISO 8601 - notation
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.june-21
- Wikidata: Q2671 (https://www.wikidata.org/wiki/Q2671)
- ISO 8601: --06-21 recurring date
Direct properties not applicable Not applicable
- day of year: 172 or 173 day - common year, leap year where different
- days remaining: 193 days
Plane XCT: no invented physical properties.
Recognition optional Filled
- Written 21 June or June 21
- ISO format --06-21
- Observances vary by country and tradition
- A date on calendars.
Capabilities and actions required Filled
- compute its weekday in a given year
- check local and international observances
- find sourced historical events
- schedule events
Hazards and failure modes required Filled
- Assuming observances are universal
- Unsourced on-this-day events
- Mixing Julian and Gregorian dates
Standards and interfaces required Filled
- ISO 8601
- National public holiday laws
Context of use required Filled
- A calendar date for scheduling, holidays and anniversaries.
- the recurring calendar date
- specific dated days in given years
Sources Filled
- Wikidata item Q2671: June 21 - identity and sense of the item
- Wikipedia: June 21 - general description of the item
Open questions
- Should dated days be separate entries?
- How should observances be linked?
- How should events be sourced?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q2671/spec.json