> For example, the first day of Fall is actually the first day of "Mehr" (the 7th month). For some reason, the Gregorian calendar has it on Sep. 22. That’s jus

> For example, the first day of Fall is actually the first day of "Mehr" (the 7th month). For some reason, the Gregorian calendar has it on Sep. 22. That’s just a convention. In Russia we use “meteorological” convention, for example, and so each season starts on the 1st of some month (March, June, September, December). It is off from the astronomical convention by ≈20 days and it is off from reality by whatever depending on your location and your feelings on what constitutes seasons.