Days of week on Hebrew calendar the "four gates". Since three arrangements cannot occur within the fixed calendar, most holidays can each occur on one of four possible days. All the holy days and festivals fall in the months of Nisan through Tishrei, months one to seven. These months always have the same number of days, alternating 30 and 29. The next two months are Cheshvan and Kislev, months eight and nine. Both or either of these months can have either 29 or 30 days, allowing for adjustments to be made and the schedule in the coming year to be manipulated. (On a regular year, Cheshvan
Year the start of the fasting month of Ramadan. A Muslim calendar year is based on the lunar cycle. The vague year, from "annus vagus" or wandering year, is an integral approximation to the year equaling 365 days, which wanders in relation to more exact years. Typically the vague year is divided into 12 schematic months of 30 days each plus 5 epagomenal days. The vague year was used in the calendars of Ancient Egypt, Iran, Armenia and in Mesoamerica among the Aztecs and Maya. It is still used by many Zoroastrian communities. A heliacal year is the interval between the