He Liqiu astronomers interpreted as the date is not fixed.

<P> World Scientific reports [tech.] News: August 8 this year is the beginning of autumn day, careful of the public have some questions: the beginning of autumn in the 8-month calendar date is not fixed, sometimes 7, sometimes .8, there are exceptions to the 9th. .Purple Mountain Observatory, Chinese Academy of Sciences researchers have made the king to explain this trend. .</ P> <P> thought, according to Wang introduced the twenty-four solar terms of the most important "members" one of the beginning of autumn to determine the specific time of the time with other solar terms are closely related. .The sun is at sports, a year of 365.2422 days back, run a week. .The sun is at the location indicated by longitude from the vernal equinox began to zero every 15 degrees together, and a return of 360-degree sun, there are twenty-four solar terms, every month there are two solar terms. .Solar term is used to reflect the cold and heat, and is essentially based on the law of the Earth around the sun determined. .</ P> <P> the king thought that since the Gregorian calendar Annals, generally have a fixed number of days in the year of 365 days, the actual number of days in the sun there is a return of the gap. .However, twenty-four solar terms are based on a return to the delineation of the exact number of days on the basis, basically a return of 24 parts, so that each solar term then corresponds to the public usually are familiar with the chronology of the Gregorian calendar ., the specific time is not fixed. .</ P> <P> return of the sun on the vernal equinox is a starting point, as long as the time to determine the vernal equinox, the other moral courage will basically determine the specific time. .Wang thought introduced, beginning of autumn equinox time, and time has a relatively close contact. .In general, the spring equinox came early, beginning of autumn will come back; equinox comes late, will come later than the beginning of autumn. .2005 -2007 as 3 years of this time was the vernal equinox at 20:34 on March 20, March 21 points and 26 02 21 March 08 07 pm; the beginning of autumn time was 7 August 18 .When 04 minutes, at 23:41 on August 7 and 8 August 05 31 minutes. .</ P> <P> "Of course, the astronomical calendar which is a complex and sometimes some unexpected circumstances, but generally will not change." Thought the king said. .</ P> <P> astronomy experts say, twenty-four solar terms astronomers in ancient China and the working people in the summary of the astronomy, meteorology and the relationship between agricultural production, created after a calendar. .Which the beginning of spring, the beginning of summer, beginning of autumn, the beginning of winter collectively, the "four goals", "Establishment" means the beginning, the beginning of seasons, respectively, generally in the annual calendar on February 4, May 5, August 7 .day and after November 7. .However, the "four goals", said the only real astronomical beginning of the season, from the climate, said the general was still in a season, such as the beginning of autumn, but temperatures in most parts of China is still very high. .</ P> </ p>.