Start of month of Av on the Hebrew calendar. Av (אָב) is the 11th month of the civil Hebrew year (12th on leap years) and the 5th month of the biblical Hebrew year. It has 30 days and corresponds to July or August on the Gregorian calendar. רֹאשׁ חוֹדֶשׁ, transliterated Rosh Chodesh or Rosh Hodesh, is a minor 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-av-2026?i=on&uc=ical-buenos-aires-5786