First of Muharram (at sundown)

“The Islamic New Year, or the First of Muharram, begins at sundown. This marks the beginning of the Islamic lunar calendar each year. For many Muslims, it begins at the first sighting of the lunar crescent after the new Moon in the month of Muharram. The crescent Moon may be visible a day or so after the new Moon, but weather and other factors may delay the sighting. Other Muslims use different criteria to determine the start of the calendar, such as the Fiqh Council of North America (FCNA), which calculates the date according to the following: The Moon must be born (become new) before sunset in Makkah, and the Moon must set after sunset. The following dates are calculated according to the FCNA, and may be a day or so earlier than a visible sighting.”