A little over two months ago I wrote about the Winter Solstice. Now that the Vernal, Spring or March Equinox is approaching there’s no better time to discuss the equinoxes, when they occur and why they are important.
There are two per year. They occur in March around the 20th day of that month and in September around the 22nd day. The March equinox or Vernal equinox will occur here in the DFW area on Thursday, March 20, 2014 at 11:57 a.m. CDT or Thursday, March 20, 2014 at 16:57 UTC.
The word origin for equinox come from the Latin words aequus (equal) and nox (night). So it stands to reason equinox literally means the time when the amount of day light hours and night time hours in one day are almost equal.
If you imagine the Earth’s equator projected out into space this is referred to as the Celestial equator. The two points where the Sun crosses this Celestial equator (see numbers 2 and 4 in the graphic above) are the equinoxes. Again, one happens in Spring and the other in Fall for both the Northern and Southern hemispheres of the planet. As we mark the Spring equinox in the Northern hemisphere the Southern hemisphere is observing it’s Fall equinox. But again, the key here is that the amount of day light hours and night time hours on this day are almost equal at about 12 hours each. This is true no matter what hemisphere you are in.
The Northern hemisphere marks the beginning of Spring which is seen as a time of rebirth and thus many or the world’s religions have celebrations at this time. Christian’s celebrate Passover and Easter around this time.