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Truth about Calendars
By admin | December 14, 2008
Moon encircles earth in 29 days, 12 hours, 44 minutes, and 3 seconds or 29.5306 days (a month). If it is multiplied by twelve, the result is 354 days, 8 hours, 48 minutes, and 34 second or 354.3672 days. This is time of one year for calendar based on moon movement (lunar calendar). There is also a calendar pursuant to sun (solar calendar), where one year time is counted based on earth duration in encircling sun that is 365 day, 5 hours, 48 minutes, and 46 second, or 365.2422 days.
In the lunar calendar, the day changes when the sunset is happened. The beginning of each month (date of one) is when the conjunction, astral conjunction, is happened or at the emergence of the new moon. The day’s turnover on the solar calendar is happened at midnight, while the beginning of each month doesn’t depend on the moon position.
Because of that, the number of days in a year is not exact. Therefore, there is no perfect calendar. To minimize errors, there must be certain years, according to agreements, that have a day longer (leap year) than ordinary years. Years in lunar calendar have normally 354 days and its leap years have 355 days, while for solar calendar respectively 365 and 366 days.
Beside the lunar calendar and solar calendar, there is also lunisolar calendar. It is a lunar calendar which is adjusted with sun’s position. Because the year of lunar calendar has 11 days earlier, so the lunisolar calendar has intercalation months (additional months; the 13th month) in every three years. This makes it has 384 days in a year, based on the sun’s position. The Christian (the Anno Domini), Iranian, and Japanese calendar is the types of solar calendars, whereas the Islamic (Hijriyya), Javanese, and Sundanese Calendar are classified as lunar calendars. As an example of lunisolar calendar is the Saka, Buddhist, Chinese, and Jews calendar.
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