Spring equinox; An astronomical event that is the beginning of Nowruz

The moment of Spring equinox arrived and with it began the Iranian Nowruz and New Year, which is based on the most accurate calendar in the world.

beginning of Spring in the Northern Hemisphere and autumn in the Southern Hemisphere. This is the beginning of the solar new year in the Iranian calendar, which is the most accurate calendar in the world.

This year, the vernal equinox arrives on March 20 at 15:33:26 (19:03:26 in Iran). . No matter where you are on earth, the vernal equinox occurs instantly everywhere and brings with it some seasonal changes that are noticeable to nature lovers around the world.

The path of the sun in the vernal equinox and the summer and winter revolution
Credit: Earth Science Picture of the Day/Universities Space Research Association

Equality of day and night

In equinox, the two hemispheres receive equal amounts of sunlight. It is often said that the length of day and night are equal. In fact, the word equinox is derived from the Latin word Aequus meaning "equal" and Nox meaning night. To our ancestors, whose timing was less accurate than ours, day and night probably seemed the same. Today we know that this equation exists but is not entirely accurate.

The fastest sunset in the equinox

The fastest sunsets and sunsets of the year occur during the equinox. that is, the time it takes for the whole sun to go below the horizon.

Spring equinox is an event in the earth's orbit around the sun. At sunrise the sun rises in the east and sets in the west. It does not matter where you live on earth, this phenomenon occurs. As the image below shows, during the equinox, the sun appears above the head at noon, as seen from the Earth's equator. This image shows the sun's location at the celestial equator, at any hour of the equinox. You have your own. that point, the point of intersection of your horizon with the celestial equator, is the hypothetical line above the true equator of the earth. During the equinox, the sun rises exactly in the east and sets in the west.

The apparent movement of the sun during the equinox
Credit: Tau'olunga/Wikimedia Commons

Other effects of the vernal equinox

Other effects in the equinox game There is a Spring that we can all experience. In the Northern Hemisphere, the vernal equinox leads to earlier sunrises, later sunsets, milder winds, and greener vegetation. Colder, dryness and leaf fall are associated.

Equinoxes and revolutions are caused by the deviation of the earth's axis and the constant motion in orbit. You can think of the equinox as an event that takes place in the imaginary dome of our sky, or an event in the Earth's orbit around the Sun.

Earth-centered view

Think about it, you can think of the celestial equator as a large circle that divides the sky into its northern and southern hemispheres. The celestial firmament is a hypothetical line that divides the sky into two parts directly above the Earth's equator. During the equinox, the sun passes through the celestial equator to enter the northern hemisphere.

The apparent motion of the sun from the earth's point of view during the equinox
Credit: Tau'olunga/Wikimedia Commons

Earth's view of space

Think of it in space, you have to think of the earth in orbit around the sun, and we all know that the earth does not rotate vertically around itself, but that its axis of rotation is tilted 23.5 degrees relative to the orbital plane around the sun. So the Earth's northern and southern hemispheres receive direct sunlight and heat.

We have a equinox twice a year, including the beginning of Spring and autumn. When the deflection of the Earth's axis and the Earth 's orbit around the Sun are combined in such a way that the axis is neither far nor near the Sun.

A quarter of the Earth's view of space during the Spring and autumn equinoxes and the summer and winter revolutions
Credit: Geosync

Change Fast Around the equator

Since the earth's motion around the sun never stops, the position of sunrise and sunset and the days when sunlight and night are almost equal change rapidly.

A sign of Spring equinox in nature

Everywhere, forget about the weather for a moment and think only of daylight. In terms of daylight, the knowledge that Spring is here and summer is on its way penetrates the entire nature of the earth's northern hemisphere. It is changing. In response to changes in daylight, birds and butterflies migrate north along the path of the sun.

Longer days bring warmer weather. People leave their winter clothes at home, the trees sprout and the plants begin a new cycle of growth. In many places Spring flowers begin to bloom.

The effect of Spring equinox in nature
Credit: Stephanie Becker

Meanwhile in the Southern Hemisphere, the days get shorter and the nights get longer. Cold air is formed. Autumn is coming and winter is on its way. LT is. Nowruz, which heralds a new day, especially in Iran and according to the Iranian calendar, is the official beginning and has remained in Iran for millennia. Nowruz focuses on fertility and new life, so it is a good opportunity to use the seeds. Families set the table for the Seventy, which is accompanied by the seven symbolic elements of nature. This ancient tradition "promotes the values of peace and solidarity between generations and within families, as well as reconciliation and neighborliness." March 21 is officially known as World Nowruz Day, although depending on calendars and Spring equinox calculations, the beginning of Nowruz can be celebrated between March 19 and 22.

Cover Photo: Spring Equinox 2013 From the perspective of NASA GOES
Credit: NOAA/NASA

Sources: EarthSky, National Geographic