These are many words that we hear in our day to day life at the start of each season. In 2021, we will see the greeted spring on March 20th with the arrival of the vernal equinox and on the date December 21st we welcome the seasons of winter with the arrival of the solstice. But aside from all these things and marking the transition from one season to the next what exactly do these words mean? Is there a difference between solstice and equinox?
To better understand all these things we should keep in mind that planet Earth is like a top and spins or we can say that the rotates from east to west making one complete rotation in just under 24 hours. But the axis of our top of the planetary is not oriented by a straight up and down but rather we can say that it’s tilted by an angle of 23.5°. And when we combine all these things we find that tilt with rotation of Earth’s which are around the Sun and it serves to provide us with noticeable variations in the length of the amount of daylight as well as a change in temperature which is during the course of the year.
The Seasons are very well explained by astronomers. That is as an artifact of our global tilt and as the Earth which moves around the Sun once every year. The Sun which shines at sometimes more on the Northern Hemisphere that is our summer and sometimes more on the Southern Hemisphere that is of our winter. And we can say that it is between each of these two extremes. There comes a time when the Sun is shining on all parts which are of our globe and in equal amounts for a whole day then the equinoxes.
From here on the planet Earth it appears to us just like as it appeared to people even before the history of dawn that the position of the midday Sun moves in the sky. On the first day which is of the summer solstice which is here in the Northern Hemisphere the noon Sun appears high in the sky. We should notice that It rises about eight hours before noon and sets about eight hours after noon. Correspondingly to all of these things our weather turns warm. At the vernal and the autumnal equinoxes that is the Sun is in the sky for approximately 12 hours. But we can say that on the first day of winter that is the winter solstice.
What is Solstice
The two solstices which we have earlier studied in our junior classes occur annually and are around June 21 and December 21.
The day of a solstice when it occurs in either hemisphere has either the most sunlight of the year that the summer solstice or the least sunlight of the year which is winter solstice for any place other than the Equator. In our childhood we loved to watch the sky blue green and along with those things we noticed different types of stars and many other things also. That is we can say that the seasonal movement of the Sun's daily path which is as seen from Earth that pauses at a northern or southern limit that is before reversing direction.
What is Equinox
The equator generally passes through the geometric center of the disk of the Sun's. This whole thing occurs twice each year that is around 20 March and 23 September. In other words we can say that it is the moment at which the center of the visible Sun is directly above the equator.
The word is derived from the Latin aequinoctium that is from aequus which means equal and nox which is genitive noctis or the night. They are not equal exactly but however due to the size which is angular of the Sun which is atmospheric refraction and the rapidly changing duration of the length of day that occurs at most latitudes that are around the equinoxes. In the hemisphere or the Southern Hemisphere is the reverse which is true. The dates which slightly vary due to leap years and factors which are different.
The Moon along with a lesser extent the planets causes orbits of Earth's which is to slightly vary from a perfect ellipse.