Ecclesiastical new moon

An ecclesiastical new moon is the first day of a schematic lunar month in a computus. Such months have a variable number of whole days, 29 or 30, whereas true synodic months can vary from about 29.27 to 29.83 days in length. Medieval authors equated the ecclesiastical new moon with a new crescent moon, but it is not a phase of the true moon. If its computus is accurate, it can be any day from the day of the astronomical new moon or dark moon to two days later (see table).

The first ecclesiastical new moon of the year to begin on or after March 8 is of special importance, since it begins the Paschal lunar month: The fourteenth day of the same schematic lunar month is the first of the year to occur on or next after March 21. This fourteenth day was loosely called the "Paschal full moon" by medieval computists. Easter is the following Sunday.

Calendar pages in medieval liturgical books indicated the ecclesiastical new moons by writing the Golden number to the left of the day of the month on which the ecclesiastical new moon would occur in the year of that Golden number. In some places the age of the moon was announced daily in the office of Prime at the reading of the martyrology. [At medieval Exeter Cathedral, it was the next day's date and age of the moon that were announced. "Et omnibus in locis suis sedentibus sit ibi quidam puer...paratus ad legendum leccionem de Martilogio, absque Iube domine, sed pronunciondo primo loco numerum Nonarum, Iduum, Kalendarum, et etatem lune qulis erit in crastino..." (And when all are sitting in their places let a boy be there ready to read the Martyrology beginning with Iube domine, but first saying the number of Nones, Ides, Kalends, and what the age of the moon will be on the morrow...) J.N. Dalton, ed., "Ordinale Exon." vol. 1, Henry Bradshaw Society, London, 1909, p. 37.]

When in the 13th century Roger Bacon complained about the discrepancy between the ecclesiastical moon and the observed lunar phases, he specifically mentioned the discrepancy involving the ecclesiastical new moon

"Quilibet computista novit quod fallit primatio per tres dies vel quatuor his temporibus; et quilibet rusticus potest in coelo hunc errorem contemplari." (Any computist knows that the prime [of the moon] is off by three or four days in our time; and any rustic can see this error in the sky.) [Roger Bacon, Opus Tertium LXX, in J. S. Brewer, ed., "Fr. Rogeri Bacon Opera quaedam hactenus Inedita". Vol. 1. H.M. Stationery Office, 1859 (Kraus Reprint 1965), p. 282.]
These complaints were finally addressed by the construction of the Gregorian calendar.

References

External links

* [http://aa.usno.navy.mil/data U.S. Naval Observatory Data Services]
* [http://home.telepath.com/~hrothgar/lunar_almanac.html Gregorian ecclesiastical new moons]
* [http://www.bodley.ox.ac.uk/dept/scwmss/wmss/medieval/mss/lat/liturg/e/006.htm Oxford, Bodleian Library MS. Lat. liturg. e. 6. (14th century)]


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • New moon — For other uses, see New moon (disambiguation). The new moon phase In astronomical terminology, the new moon is the lunar phase that occurs when the Moon, in its monthly orbital motion around Earth, lies between Earth and the Sun, and is therefore …   Wikipedia

  • New Year — For other uses, see New Year (disambiguation). The New Year is the day that marks the beginning of a new calendar year, and is the day on which the year count of the specific calendar used is incremented. For many cultures, the event is… …   Wikipedia

  • New Year's Day — • Since there was no necessary starting point in the circle of the year, we find among different nations, and among the same at different epochs of their history, a great variety of dates with which the new year began. . . Catholic Encyclopedia.… …   Catholic encyclopedia

  • New Kadampa Tradition — NKT redirects here. For other uses, see NKT (disambiguation). Part of a series on Buddhism Outline · Portal …   Wikipedia

  • Paschal Full Moon — The Paschal Full Moon roughly corresponds to the first full moon of the northern Spring. The name Paschal is from Pascha which is a transliteration of the Greek word, which is itself a transliteration of the Hebrew pesach, both words meaning… …   Wikipedia

  • Full moon — [ Galileo spacecraft on 7 December 1992. The color is enhanced in the sense that the CCD camera is sensitive to near infrared wavelengths of light beyond human vision.] Full moon is a lunar phase that occurs when the Moon is on the opposite side… …   Wikipedia

  • Cycle of the moon — Cycle Cy cle (s? k l), n. [F. ycle, LL. cyclus, fr. Gr. ky klos ring or circle, cycle; akin to Skr. cakra wheel, circle. See {Wheel}.] 1. An imaginary circle or orbit in the heavens; one of the celestial spheres. Milton. [1913 Webster] 2. An… …   The Collaborative International Dictionary of English

  • Opposition to cults and new religious movements — Opposition to cults and to new religious movements (NRMs) comes from several sources with diverse concerns. Some members of the opposition have associations with cult watching groups which collect and publish critical information about one or… …   Wikipedia

  • 2000 New Year Honours — The insignia of the Grand Cross of the Order of St Michael and St George: Andrew Wood was awarded the Grand Cross in this Honours list. The New Year Honours 2000 for the United Kingdom were announced on 31 December 1999, to celebrate the year… …   Wikipedia

  • Computus — (Latin for computation ) is the calculation of the date of Easter in the Christian calendar. The name has been used for this procedure since the early Middle Ages, as it was one of the most important computations of the age. In principle, the… …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.