If you need exact dates for a specific year (especially astronomical ones), consult an online equinox/solstice calculator or an almanac, as times vary globally due to time zones.
Many cultures define seasons differently: when the seasons start and end
These are based on the annual temperature cycle and the Gregorian calendar. Meteorologists break the year into four three-month groups to make record-keeping and forecasting more consistent. The Astronomical Calendar (The "Official" Dates) If you need exact dates for a specific