Thursday, 13 April 2017

When is Easter?

Credit: Android Central

Have you noticed
● Easter is on a different weekend each year
● there’s often a full moon just before Easter

● there was a full moon on Tuesday of this week (11 April)

● Easter is this weekend?

When is Easter? – simple answer
Easter Sunday is the first Sunday after the first full moon on, or after, 21 March each year. Other days of Easter are positioned around the date of Easter Sunday – Easter Friday (Good Friday etc.) is two days before – Easter Monday the day after, etc.

Applying this rule to 2017
● 12 March was a full moon

● next full moon (i.e. first on, or after, 21 March) was on Tuesday 11 April

● so Easter Sunday is the first Sunday after 11 April – Sunday 16 April 2017

Earliest possible Easter Sunday
“In 1818, as a paschal full moon fell on Saturday March 21 (the Spring 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.” – Wikepedia1

Latest possible Easter Sunday
“In 1943 a full moon fell on Saturday March 20. As this was before the Equinox the next 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.” – Wikepedia2

When is Easter? – complex answer

1 Wikipedia: “Ecclesiastical full moon”, “Earliest Easter”,

2 Wikipedia: “Ecclesiastical full moon”, “Latest Easter”,
/ ecclesiastical full moon 14th day ecclesiastical lunar month ecclesiastical moon) ecclesiastical lunar calendar ecclesiastical lunar calendar spans the year lunar months 30 29 days approximate observed phases of the moon true synodic month length vary 29.27 29.83 days moment of astronomical opposition 14.75 days after the previous conjunction sun moon 28 days lunar month ecclesiastical full moons Gregorian lunar calendar dates of astronomical opposition day beginning midnight at 0 degrees longitude within a day or so astronomical opposition single moment entire earth hour and day opposition measured having taken place vary with longitude ecclesiastical calendar 14th day of the lunar month reckoned in local time considered day of the full moon at each longitude schematic lunar calendars get out of step with the moon checking their performance compare variation astronomical new moon standard time of 6 A.M. last day of a 30 day month 6 P.M. end of day last day of a 29 day month medieval period age of the ecclesiastical moon announced daily office of Prime reading of the martyrology Book of Common Prayer Protestant Episcopal Church of the United States of America dates paschal full moons 19 years Gregorian Easter cycle Golden Number date in March or April paschal full moon falls year of the cycle practice some editions Book of Common Prayer of the Church of England /