Start of month of Iyyar on the Hebrew calendar. אִיָיר (transliterated Iyyar or Iyar) is the 2nd month of the Hebrew year, has 29 days, and corresponds to April or May 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-iyyar-2024?uc=ical-jewish-holidays-all