The vernal equinox arrives tonight at 04:29:51 UT (57467.18740). That's 9:30 pm on Saturday night here in California. It means that I am officially on Spring Break, so I'll have more time to post here for the next week, if I don't get called for jury duty. It also means that holidays are coming for all my Catholic, Protestant, Orthodox and Jewish relatives.
According to the Catholic Church, Easter falls on the first Sunday after the first full moon of spring, which officially starts March 21 (57468). (It actually tended to fall on that date in the 20th century, but is gradually getting earlier, and won't return to March 21 until after 2100, when a leap year is skipped.) The next full moon is on Wednesday, March 23 (57470), so Easter this year falls on Sunday, March 27 (57467) for Catholics and Protestants.
Originally, Easter fell during the Jewish festival of Passover, or Pesach, which starts on 15 Nissan. Since the Jewish calendar is lunar, the 15th is always a full moon. However, because 12 lunar months is less than the solar year, sometimes leap months are added, and the date of Passover gets pushed one month, as in this year. Passover in 2016 (5776 AM) begins in the evening of Friday, April 22 (57501), and ends in the evening of Saturday, April 30 (57509).
Eastern Orthodox churches still follow the Julian calendar, in which the dates currently fall 13 days after the Gregorian dates, so that March 21 Julian occurs on April 3 Gregorian. In addition, the lunar phases are calculated as happening 4 or 5 days later than they actually do, which means that Orthodox Easter this year is the Sunday after Wednesday, April 14 Julian (April 27 Gregorian, 57506), which is April 18 Julian (May 1 Gregorian, 57510).
As for me, I'm just going to celebrate that it's Spring Break!
3:11 pm PDT
CE 2016 March 19 Gregorian
AD 2016 March 6 Julian
9 Adar II 5776 AM