Knowing about Vernal Equinox (March Equinox)!
Sahil Wani
The March or Vernal or northward equinox is the equinox on the Earth when the sub-solar point (the sub-solar point on any planet is a particular point at which its sun is perceived to be directly overhead or in other words at Zenith. The Zenith is basically an imaginary point directly above a particular location, on the imaginary “Celestial Sphere”) appears to leave the southern hemisphere and cross the celestial equator, heading northward as seen from Earth.
The March equinox is known as the Vernal Equinox (spring equinox) in the Northern Hemisphere and as the autumnal equinox in the Southern Hemisphere. On the Gregorian calendar (most common calendar used in the world), the Northward equinox can observe on 20 March each year. Present year 2021 with unfortunate prolonged epidemic, the folk notice this with desolation heart and vague mood.
Well somehow the confusion about the date can be understood as the computed time slippage. Confusion about the date? Yeah! Because, the Northward equinox can occur as early as 19 March or as late as 21 March at Greenwich.
So let me explain the computed time slippage, for a common year the computed time slippage is about 5 hours 49 minutes later than the previous year, and for a leap year 18 hours and 11 minutes earlier than previous year. Balancing the increases of the common years against the losses of the leap years keeps the calendar date of March equinox from drifting more than one day from 20 March each year. So between the extreme date points 19 & 21, the March 20 fits after balancing all the stuff.
Vernal Equinox will come about across Asia, Central America, Europe and obviously northern Africa in the Northern hemisphere on March 20.
Facts about Spring Equinox
• The term equinox comes from the Latin word ‘equinoxium’ meaning ‘equality between day and night.’ And vernal comes from Latin word ver which means spring.
• Conventional wisdom suggests that on the equinox everybody on Earth gets to experience a day and night of equal lengths- 12 hours of daylight and 12 hours of night time.
• Many cultures around the world hold banquet and celebrate festivals and holidays to mark the March equinox.
• In the Northern hemisphere, astronomers and scientists use the March equinox as the start of spring, which ends on the June solstice, when astronomical summer begins.
• Last but very surprising fact, in 2020, spring was that it arrived earlier than it had in 124 years.
