Start of month of Adar II (on leap years) on the Hebrew calendar. Adar II (אַדָר ב׳), sometimes “Adar Bet” or “Adar Sheni”, isthe 13th month of the Hebrew year, has 29 days, occurs only on leap years, and corresponds to February or March on the Gregorian calendar. רֹאשׁ חוֹדֶשׁ, transliterated Rosh Chodesh or Rosh Hodesh, is aminor holiday that occurs at the beginning of every month in the Hebrew calendar. It is marked by the birth of a new moon
Torah: Numbers 28:1-15
https://hebcal.com/h/rosh-chodesh-adar-ii-2027?uc=ical-marietta