Community hub
Recent from talks
Contribute something to knowledge base
Content stats: 0 posts, 0 articles, 0 media, 0 notes
Members stats: 0 subscribers, 0 contributors, 0 moderators, 0 supporters
Subscribers
Supporters
Contributors
Moderators
Hub AI
Ecclesiastical full moon AI simulator
(@Ecclesiastical full moon_simulator)
Hub AI
Ecclesiastical full moon AI simulator
(@Ecclesiastical full moon_simulator)
Ecclesiastical full moon
An ecclesiastical full moon is formally the 14th day of the ecclesiastical lunar month in an ecclesiastical lunar calendar.[citation needed] The ecclesiastical lunar calendar spans the year with lunar months of 30 and 29 days which are intended to approximate the observed phases of the Moon.[citation needed] Since a true synodic month has a length that can vary from about 29.27 to 29.83 days, the moment of astronomical opposition tends to be roughly 14.75 days after the previous conjunction of the Sun and Moon (the new moon). The ecclesiastical full moons of the lunar reckoning tend to agree with the (Gregorian calendar) dates of astronomical opposition, referred to a day beginning at midnight at 0° longitude, to within a day or so. However, the astronomical opposition happens at a single moment for the entire Earth: the hour and day at which the opposition is measured as having taken place will vary with longitude. In the ecclesiastical calendar, the 14th day of the lunar month, reckoned in local time, is considered the day of the ecclesiastical full moon at each longitude.[citation needed]
Beginning in medieval times, the age of the ecclesiastical moon was announced daily at the canonical hour of Prime during the reading of the martyrology. This was still done by Roman Catholics using the extraordinary form of the Roman Rite (according to the 1962 Roman Breviary).
The paschal full moon is the particular 'ecclesiastical full moon' that is used in the calculation of the date of Easter. The name paschal is derived from Pascha, a transliteration of the Aramaic word meaning Passover. This 'paschal full moon' is the one that falls on or after March 21. (March 21 is the ecclesiastical equinox, the date fixed by the Gregorian reform of the calendar as a fixed reference date for the Spring Equinox in the Northern hemisphere; the actual Equinox can fall on March 19, 20 or 21). The date of Easter is determined as the first Sunday after that specific full moon. This "full moon" does not necessarily correspond directly to any astronomical event, but is instead the 14th day of a lunar month, determined from tables. It may differ from the date of the actual full moon by up to two or even three days.
The calculations to determine the date of the paschal full moon can be described as follows:
In other words, Easter falls from one to seven days after the paschal full moon, so that if the paschal full moon is on Sunday, Easter is the following Sunday. Thus the earliest possible date of Easter is March 22, while the latest possible date is April 25.
In 1818, as the paschal full moon fell on Saturday March 21 (the ecclesiastical fixed date for the Equinox), Easter was the following day—Sunday March 22—the earliest date possible. It will not fall on this date again until 2285, a span of 467 years.
In 1943 an ecclesiastical full moon fell on Saturday March 20. As this was before March 21, the next ecclesiastical full moon, which fell on Sunday April 18, determined the date of Easter—the following Sunday, April 25. It will not fall on this date again until 2038, a span of 95 years.
For a detailed discussion of the paschal computations, see Date of Easter (the Computus).
Ecclesiastical full moon
An ecclesiastical full moon is formally the 14th day of the ecclesiastical lunar month in an ecclesiastical lunar calendar.[citation needed] The ecclesiastical lunar calendar spans the year with lunar months of 30 and 29 days which are intended to approximate the observed phases of the Moon.[citation needed] Since a true synodic month has a length that can vary from about 29.27 to 29.83 days, the moment of astronomical opposition tends to be roughly 14.75 days after the previous conjunction of the Sun and Moon (the new moon). The ecclesiastical full moons of the lunar reckoning tend to agree with the (Gregorian calendar) dates of astronomical opposition, referred to a day beginning at midnight at 0° longitude, to within a day or so. However, the astronomical opposition happens at a single moment for the entire Earth: the hour and day at which the opposition is measured as having taken place will vary with longitude. In the ecclesiastical calendar, the 14th day of the lunar month, reckoned in local time, is considered the day of the ecclesiastical full moon at each longitude.[citation needed]
Beginning in medieval times, the age of the ecclesiastical moon was announced daily at the canonical hour of Prime during the reading of the martyrology. This was still done by Roman Catholics using the extraordinary form of the Roman Rite (according to the 1962 Roman Breviary).
The paschal full moon is the particular 'ecclesiastical full moon' that is used in the calculation of the date of Easter. The name paschal is derived from Pascha, a transliteration of the Aramaic word meaning Passover. This 'paschal full moon' is the one that falls on or after March 21. (March 21 is the ecclesiastical equinox, the date fixed by the Gregorian reform of the calendar as a fixed reference date for the Spring Equinox in the Northern hemisphere; the actual Equinox can fall on March 19, 20 or 21). The date of Easter is determined as the first Sunday after that specific full moon. This "full moon" does not necessarily correspond directly to any astronomical event, but is instead the 14th day of a lunar month, determined from tables. It may differ from the date of the actual full moon by up to two or even three days.
The calculations to determine the date of the paschal full moon can be described as follows:
In other words, Easter falls from one to seven days after the paschal full moon, so that if the paschal full moon is on Sunday, Easter is the following Sunday. Thus the earliest possible date of Easter is March 22, while the latest possible date is April 25.
In 1818, as the paschal full moon fell on Saturday March 21 (the ecclesiastical fixed date for the Equinox), Easter was the following day—Sunday March 22—the earliest date possible. It will not fall on this date again until 2285, a span of 467 years.
In 1943 an ecclesiastical full moon fell on Saturday March 20. As this was before March 21, the next ecclesiastical full moon, which fell on Sunday April 18, determined the date of Easter—the following Sunday, April 25. It will not fall on this date again until 2038, a span of 95 years.
For a detailed discussion of the paschal computations, see Date of Easter (the Computus).