Dates of Holy Days of Obligation 2009 Thursday, January 1, 2009 - Mary, Mother of God - obligation to attend Mass Sunday, May 24, 2009 - Ascension of the Lord - transferred to Sunday Saturday, August 15, 2009 - Assumption of Mary - not a day of obligation Sunday, November 1, 2009 - All Saints - obligation to attend Mass Tuesday, December 8, 2009 - Immaculate Conception - obligation to attend Mass Friday, December 25, 2009 - Christmas - always a holy day 2010 2010 Friday, January 1, 2010 - Mary, Mother of God - obligation to attend Mass Sunday, May 16, 2010 - Ascension of the Lord - transferred to Sunday Sunday, August 15, 2010 - Assumption of Mary - obligation to attend Mass Monday, November 1, 2010 - All Saints - not a day of obligation Wednesday, December 8, 2010 - Immaculate Conception - obligation to attend Mass Saturday, December 25, 2009 - Christmas - always a holy day Mass Schedule for Holy Days Vigil           8:00 pm on the evening before the Holy Day When there is a Holy Day vigil mass there is no 5:30 pm mass Holy Day           6:30 am            9:00 am          12:15 pm            5:30 pm             8:00 pm