Why Leap Year - Gregorian Calendar - Seasons
This video discusses the Julian and Gregorian calendars, Leap Years, Seasons. The need for Leap Days to keep the calendar in sync with the seasons is explained. There is a brief discussion of precession.
Useful websites include: https://www.grc.nasa.gov/www/k-12/Num... ; https://eclipse.gsfc.nasa.gov/SEhelp/... ; https://pumas.nasa.gov/files/04_21_97... ;
astronomy.gpclements.com
Introductory Astronomy
Prof. Greg Clements