The vagaries of our Gregorian calendar, such as the inclusion of a leap day in century years divisible by 400 also help contribute to the seasonal date shift.This shift in dates happens because the Earth's elliptical orbit changes the orientation of its axis and because our year does not contain an even number of days.It is predicted that next year spring will officially begin on March 19.From the years 1980 through 2102, it comes no later than March 20.In fact, during the 20th century, March 21 was actually the exception rather than the rule, with the equinox landing on that day only 36 times. But now for North Americans, spring begins on March 20.When most of us were growing up, it always seemed that the first day of spring was on March 21, not March 20.More precisely at that moment, the sun will be shining directly down on the equator at a point over the Pacific Ocean, roughly 1,900 miles (3,100 km) southeast of the Hawaiian Islands.It will then be shining equally on both halves of the Earth. Here the sun comes to one of two places its rays shine directly down on the where equator. PDT) the spring (or vernal) equinox occurred for the year 2023. The vernal equinox also marks the beginning of spring, which lasts until the summer solstice which is on June 20 or 21 in the Northern Hemisphere, and December 21 or 22 in the Southern Hemisphere.Astronomically it is defined by the seasons.While in the Southern Hemisphere, the equinox falls on September 22 or 23, when the Sun moves south across the celestial equator.The vernal equinox falls about March 20 or 21 in the Northern Hemisphere, when the Sun crosses the celestial equator which goes north.Either of the two points in the sky where the ecliptic (the Sun’s annual pathway) and the celestial equator intersect. At that time the day and night are of equal length. There are two moments in the year when the Sun is exactly above the Equator. On the equinox date, the length of daylight is actually longer than darkness by several minutes and symbolizes the end of winter and the start of spring in the Northern Hemisphere. The spring equinox occurs at 5:58 pm on March 20, 2019.Vernal equinox 2023 brings spring to the Northern Hemisphere and for the year 2023, the date is March 20. The days start to become longer than the nights until the summer solstice, the longest day of the year. When the sun crosses the celestial equator from south to north, people in the northern hemisphere experience the vernal (spring) equinox. We also have equal amounts of daylight and darkness. As we view the Sun on those days, it rises due east and sets due west. There are two days each year when the plane of the ecliptic and the celestial equator intersect both of these days are called the equinox. it is the first day of spring! At least it is for the northern hemisphere.īecause the Earth travels around the Sun each year tilted at a 23½ degree angle, the celestial equator (the extension of the Earth's equator on to the sky) is not on the same plane as the ecliptic (the path that the Earth and the planets travel around the Sun). Question #20 – On Wednesday, March 20 th, the northern hemisphere will experience the vernal equinox.
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