Equinox and Solstice | Differences, Definition and Facts.

Planets are somewhat inclined on their axes as they orbit the sun. It implies that different places on earth receive different amounts of sunlight throughout the year. That’s how the seasons shift on earth. We experience different seasons based on where the earth is in its orbit around the sun. There would be no seasons if the earth were not inclined on its axis. We wouldn’t have day or night if the earth didn’t rotate on its axis. The article thoroughly covers the major concepts and differences between the equinox and solstice.

What Causes the Seasons on Earth?

The axial tilt, or 23° tilt in the earth’s axis, causes the seasons on earth. Without an inclination angle, we wouldn’t experience seasons as we do. Life on earth would have evolved differently to account for more stable weather and climatic circumstances at each of the earth’s natural latitudes. Because of this tilting, the Southern Hemisphere is occasionally somewhat more exposed to the sun’s rays than the Northern Hemisphere, and vice versa. It has a range of impacts on the earth, such as considerable temperature changes, climatic variations, and an increase or decrease in the amount of light and energy from the sun, which we commonly experience as seasons.

The Equinox (Vernal & Autumnal)

It can be experienced only twice a year when the earth’s axis is inclined (or tilted) neither towards nor away from the sun, resulting in “nearly” equal amounts of sunlight and nighttime at all latitudes. These occurrences are known as equinoxes. The Latin words ‘aequus’ (equal) and ‘nox’ are the origins of the word equinox (night). On these two equinoxes, the sun is exactly at noon at the equator. 

The “almost” uniform lengths of day and night are caused by the sun’s rays being bent or refracted, making it appear that the sun is located above the horizon, whereas it is actually below the horizon. In addition, because the sunrise and sunset occur longer at higher latitudes (those farthest from the equator), the days become slightly longer there. Therefore, during the equinox and for a few days during and after the equinox, the length of the day will vary from around 12 hours and 6 minutes at the equator to 12 hours and 8 minutes at 30 to 12 hours and 16 minutes at 60 degrees latitude.

Interesting Facts: The equinox takes place twice a year. However, each hemisphere only experiences it once a year. The southern hemisphere’s spring equinox coincides with the northern hemisphere’s autumnal equinox. The earth’s tilt causes the equinox and the seasons. During the equinox, day and night aren’t exactly equal.

The Solstices (Summer & Winter)

The term solstice evolved from the Latin word solstitium, which comes from sl, “sun,” and sisters, “to stand still or stationary,”. As a result, the word “solstitium” means “the standing still or stationery of the sun.”

The earth’s inclination (or tilt) towards or away from the sun is at its maximum during the summer solstice. As a result, the sun appears at its maximum elevation on the summer season’s solstice. Its noontime position remains constant for a few days before and after the summer solstice. The summer solstice occurs when the sun is over the Tropic of Cancer, which spans Mexico, the Bahamas, Saudi Arabia, Egypt, India, and southern China and is situated at 23.5° latitude North. The sun is at its maximum point in the sky for all locations north of the Tropic of Cancer, and it is the longest day of the year.

During the winter solstice, the earth experiences its shortest day and longest night of the year. It occurs in the Northern Hemisphere when the sun is above the Tropic of Capricorn, stretching through Chile, Australia, Southern Brazil, and Northern South Africa. It is situated 23.5° south of the equator.

Solstices are frequently observed by various traditional festivals, the most famous of which is the Christmas holiday, which is observed a few days after the December Solstice and draws on ancient pagan customs that have existed for thousands of years.

Difference Between Equinox and Solstice

You may be aware that the solstices and equinoxes mark the beginning and end of each season on earth, but how do you differentiate between the two? Do they all relate to a similar thing under different names? Well, a solstice and an equinox are kinds of the opposite. Let’s understand the difference between the equinox and solstice. 

The equinox and solstice differences can be best explained as follows:

Equinox	Solstice
The equinox is considered the time of year when day and night are equal in length in both hemispheres. It happens twice a year. During this time, the sun is just above the equator.	The solstice is the time of the year when day and night are either shorter or longer in both hemispheres. It happens twice a year.
The term “equinox” evolved from the Latin words ‘aequus’, which denotes equal, and ‘nox’, which denotes night. The days and nights are not exactly but almost equal.	The term “solstice” evolved from the Latin words “Sol” (sun), which denotes sun, and “sister”, which denotes to stop or stationery. The longest or the shortest days of the year belong to this season.
The equinox occurs twice a year. During this time, the sun’s centre is above or below the same level as the earth’s equator.	The solstice occurs twice a year because of the earth’s inclination towards the sun —once during the inclining of the North pole and once during the inclining of the South pole. During the summertime (in the northern hemisphere), the northern pole is inclined toward the sun, and during the winter (in the northern hemisphere), the southern pole is inclined toward the sun.
Equinox is considered the time of year when the sun is closest to the equatorial plane, giving day and night roughly equal length.	Solstice is when the earth is farthest from the equatorial plane, lengthening day and night.
Every year, it takes place around March 22 and September 22.	Every year, it takes place around June 21 and December 22.
The equinoxes come in two seasons: Equinox in March, also known as the spring or vernal equinox. (Around the northern hemisphere). Equinox in September, also known as fall or autumnal equinox (around the northern hemisphere).	The solstice comes in two seasons: Winter solstice (which commences on December 22 in the northern hemisphere) is considered the shortest day of the year. Summer solstice (commences on June 21 in the northern hemisphere): It is the year’s longest day.
The earth’s southern hemisphere also experiences two equinoxes these days.	The earth’s southern hemisphere coincides with the winter solstice in June and the summer solstice in December.

Conclusion

According to astronomy, our planet experiences four distinct seasonal changes every year: two equinoxes (one in March and one in September) and two solstices (one in June and one in December). Several variables related to the relationship between the sun and earth, the inclination in the earth’s axis, and how those things play out for each of us living here on the third rock (earth) from the sun have led scientists to target specific dates at the beginning and end of each of our seasons. Understanding these seasons play a crucial role in comprehending higher-level topics with ease. Thus, students must understand these seasons well. 

Frequently Asked Questions.

1. Explain the equinox and solstice difference?

Ans. As the equi- prefix might imply, the equinox occurs when daytime and nighttime are of equal duration. It also signifies the beginning of spring (vernal equinox) and fall (autumnal equinox).

The solstice, meanwhile, signifies the commencement of summer and winter and can be the longest or shortest day of the year (winter solstice).

Sol signifies the sun, and solstices are days with maximum daylight.

2. What does a solstice sound like?

Ans. Solstice can be defined as the time when the sun is at its maximum or least point at noon, resulting in the formation of the shortest and longest days of the year. The summer solstice is exemplified by the longest day of the year. 

3. What is the shortest and longest day of the year?

Ans. December commemorates the winter solstice, also considered the day when there are the least daylight hours of the year in the northern hemisphere. For this reason, it is often termed the shortest day or the longest night of the year.

The longest day of the year, June 21, marks the beginning of the summer solstice in the Northern Hemisphere. The sun is at its highest and most northern position in the sky on the June solstice (also known as the summer solstice).

4. Define equinox solstice

Ans. The solstice and equinox are explained as follows, Equinox is one of the two phases of the year when the lengths of day and night are almost equal. Spring officially begins on the vernal equinox, while fall officially begins on the autumnal equinox. Solstice is one of the two phases of the year when there is either the greatest or the smallest amount of daylight in a single day. Solstices are ushered by winter and summer equinoxes.