new Delhi: This year, the March equinox, or the astronomical start of spring in the Northern Hemisphere, falls on March 20. Earth has two types of seasons, namely meteorological and astronomical. The tilt of the Earth’s axis with respect to the Sun-Earth plane, and the position of the planet during its orbit around the Sun are responsible for the “celestial” seasons.
“Meteorological seasons” are based on seasonal temperature variations modified by fluctuations in the amount of solar radiation received by the Earth’s surface during a year. Every year, the spring season begins on March 1 and ends on May 31.
The equinoxes and solstices occur as a result of the Earth’s tilt on its axis and the planet’s constant motion as it orbits the Sun.
An equinox occurs twice a year when the Sun is just above the Earth’s equator, and the day and night are of equal length. It is a phenomenon in which a planet’s sub-solar point passes through its Earth’s equator. The subsolar point on a planet is the point at which the Sun is considered to be directly overhead, and where the Sun’s rays strike the planet exactly perpendicular to the surface.
There are two equinoxes in a year, namely the March and September equinoxes. The March equinox is known as the spring equinox or vernal equinox in the Northern Hemisphere. During this, The seasons reverse in the Southern Hemisphere, where it would be autumn.
This year, the seasons together will be on March 20th, According to NASA, at 15:33 UTC (9:03 pm IST).
10 things you need to know about the first day of astronomical spring in the Northern Hemisphere.
1. At the March equinox, the Sun will pass just above the equator, giving roughly equal amounts of day and night on all parts of the Earth. The equinox results in approximately 12 hours of daylight and 12 hours of night at the equator.
2. However, at the equinox, day and night are not exactly the same. Most regions on Earth see more daylight than at the equinoxes at night. There are two reasons for this. One of them is how sunrise and sunset are defined. The second reason is atmospheric refraction of sunlight. The refraction of sunlight by Earth’s atmosphere is another reason why the day at the equinox is longer than 12 hours.
Since sunrise and sunset are defined as the exact moment the upper edge of the Sun’s disk touches the eastern and western horizons, respectively, the time taken for the Sun to set completely is slightly longer in the day than at night at the equinox. Makes long. , according to timeanddate.com.
The upper edge of the Sun is visible from Earth several minutes before the edge actually reaches the horizon due to atmospheric refraction or bending of light. Furthermore, at sunset, the Sun can be seen for several minutes after sinking below the horizon, making every day on Earth, including the days of the equinox, at least six minutes longer without atmospheric refraction.
3. The March equinox is the first equinox of the year. The second equinox, called the September equinox, occurs every year on or around September 22. It marks the spring equinox in the Southern Hemisphere and the autumn equinox in the Northern Hemisphere.
4. The March equinox will bring earlier sunrise, later sunset, softer winds and budding plants in the Northern Hemisphere. Inverted weather will be experienced in the Southern Hemisphere. There will be later sunrises, earlier sunsets, colder winds and dry, falling leaves.
5. People living in the Northern Hemisphere can see the Sun as it moves slightly north on the horizon until the June solstice.
The June solstice is the event when the Sun reverses directions while moving back south.
6. After the March equinox, the Northern Hemisphere begins to tilt more toward the Sun, resulting in increased daylight hours and warmer temperatures.
7. The word Equinox is derived from two Latin words – Neutral And Knox, Which means equal and night respectively.
8. At the March equinox, the Sun crosses the celestial equator, which moves north when viewed from Earth. CThe celestial equator is the great circle in which the plane of the terrestrial equator intersects the celestial sphere. The first point of Aries is the point where the Sun crosses the celestial equator to the north.
9. The March equinox does not fall on the same date every year. The March equinox has occurred only twice – on March 21 – 2003 and 2007. During the last decades of the century, the March equinox is more likely to occur on March 19.
10. The March equinox is a time of transition and new beginnings in many cultures. According to timeanddate.com, the date of the March equinox plays a large role in calculating the dates for celebrating the Jewish Passover and Christian Easter. The Jewish holiday Passover commemorates the emancipation of the Hebrews from slavery in Egypt. Easter is one of the major holidays in Christianity, which symbolizes Resurrection of Jesus Christ.
Iranian New Year, or nowruz, which has been celebrated for more than 3,000 years, occurs on the March equinox. Meanwhile, some people in Japan remember their ancestors by celebrating higano During the March equinox and the September equinox. higanoWhich means “other coast”, is a Buddhist holiday that celebrates the spiritual move from the world of suffering to the world of enlightenment.