Calendar year ("leap days" or "intercalary days"). The Gregorian year, which is in use in most of the world, begins on January 1 and ends on December 31. It has a length of 365 days in an ordinary year, with 8,760 hours, 525,600 minutes, or 31,536,000 seconds; but 366 days in a leap year, with 8,784 hours, 527,040 minutes, or 31,622,400 seconds. With 97 leap years every 400 years, the year has an average length of 365.2425 days. Other formula-based calendars can have lengths which are further out of step with the solar cycle: for example, the Julian calendar has an average
Jewish Talmudic Calendar the previous evening, at the time of sunset, when three mediums sized stars appear. Practically it begins from 6:00 p.m. (18:00) Jerusalem time (16:00 Universal Time). A day is divided into 24 hours, each with 1080 parts (halakim). Thus each minute is composed of 18 halakim; each halakim is 3.33 seconds. There are twelve months in a common year, and thirteen months in a leap year. The New Years Day (Rosh Hashana) is Tishri 1. The months are 30 days and 29 days in turns. A regular common year is 354 days; while a regular leap year is 384 days