For an observer on Mount Sina: 2285m, N 28� 32' 23", E 33� 58' 24"
Time: UT1. (gregorian calendar)
Day changes at sunset on mount Sina.
Two Church canons are implemented:
First: March 21 must always be the date of vernal equinox day.
Second: Easter Day must be first Sunday after first Fullmoon (spring Fullmoon) after vernal equinox.
Decision on leap year:
2010 Mar 20 15:55:17.0 Sunset
2010 Mar 20 17:36:14.5 Vernal Equinox
Conclusion: Vernal Equinox on March 21 by political calendar, therefore March 22 by ecclesiastical calendar. Ecclesiastical year must be leap one, that is, February must number 29 days.
Decision on Easter Day date:
2010 Mar 30 07:13:36.8 Spring Fullmoon
2010 Mar 30 16:00:50.1 Sunset
Conclusion: Spring Fullmoon at 2010 Mar 30 by both political and ecclesiastical calendar.
Easter Day date: Sunday April 4, 2010.
Acknowledge: I have retrieved data from http://aa.usno.navy.mil/data/