This year, the Eastern Orthodox celebrate the Holy Ascension today, on the 6th of June: http://www.cicts.org/default.asp?id=819
From Wikipedia: “In the Eastern Church, The Feast of Ascension, known in Greek as Analepsis, the “taking up”, and also as the Episozomene, the “salvation from on high”, denoting that by ascending into his glory Christ completed the work of our redemption. Ascension is one of the Twelve Great Feasts of the Orthodox liturgical year.
The feast is always observed with an All-night vigil. The day before is the Apodosis (leave-taking) of Easter (i.e., the last day of the Feast of Easter). Before the Vigil, the Paschal hours are said for the last time and the Paschal greeting is exchanged.
Christ is ascended!