First day of spring: here's what you need to know about the Spring Equinox of March 20, 2019

From here the end of the day, spring will be officially arrived – even if it still does not seem to go in your city. March 20, 2019 marks the spring equinox – the first official spring day in the northern hemisphere. This day is unique in that the duration of the day and night is almost equal, says NASA.

The spring equinox does not always arise on March 20th, but it will always have the same meaning: a new season. Here's what you need to know about the spring equinox.

What is an equinox?

Equinox means "equal night" in Latin. And at the autumn and spring equinox, that's exactly what's happening – there's an equal number of days and nights. According to NASA, Earth's orbit is in exactly the right place to align with the sun. At the equinox, which happens twice a year, both hemispheres receive the same amount of daylight. While the spring equinox occurs in the northern hemisphere, the autumn equinox occurs in the southern hemisphere.

The spring equinox could occur on March 19, 20 or 21, depending on the year. Six months later, the autumn equinox will take place.

The accelerated video above compresses the Earth's long orbit in about 12 seconds – during which the spring and autumn equinoxes occur.

When exactly is the spring equinox this year?

Contrary to popular belief, a marmot does not determine when winter will end and spring will begin. The equinox of spring and autumn, as well as summer and winter solsticeoccur at specific times determined by Earth's orbit around the sun. The seasons are caused by the fact that the Earth is tilted 23.5 degrees on its axis, according to the National Weather Service. The spring equinox this year will take place at exactly 5:58 pm. EDT March 20th.

What will change?

Even if you do not immediately notice obvious signs of spring, they will be there. For several days before and after the equinox, the duration of the day varies between 12 hours and 6 and a half minutes and 12 hours and 16 minutes, depending on your position relative to the Earth's equator. The days will get a little longer at the highest latitudes, farther from the equator, as it takes a little longer to get up at sunrise and sunset.

You may not yet feel the warm rays of the sun through the lush trees, but rest assured, spring is upon us for the Northern Hemisphere.