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What is the vernal equinox?

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2015-03-03 16:14:28
2015-03-03 16:14:28

The vernal equinox is the day in spring ("vernal") when the daylight and nighttime portions of the day are the same length ("equinox"). It's officially the "first day of spring", though in terms of the actual weather it's usually more like "about a third of the way into spring-like conditions".

There are two days every year where the daylight and nighttime portions last 12 hours each: the vernal equinox and the autumnal equinox. You should be able to guess what the autumnal equinox is, since unlike vernal, "autumnal" is fairly close to (one of) the English words for the season.

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2013-10-30 01:05:51
2013-10-30 01:05:51

The word "vernal" refers to the season of spring, as the word autumnal refers to the season of autumn, or fall. The vernal equinox for one half of the Earth is the start of the Spring season, and one of two times a year when the day and night are roughly equal in length for most of the planet. At these times the Sun crosses the plane of the Earth's equator. The vernal equinox for the Northern Hemisphere is the March equinox (March 20). The vernal equinox for the Southern Hemisphere is either September 22 or 23, the day termed the autumnal equinox for the north.

Every year the Earth goes once around the Sun; that is, after all, the definition of a year. The Earth spins on its axis, and this axis happens to be tilted about 23.5 degrees relative to Earth's orbital plane. As a result, for half of each year, the northern hemisphere is tilted toward the Sun for the other half the southern hemisphere tilts toward the Sun. This causes the different seasons of the year.

When the north is tilting toward the Sun, the Northern Hemisphere experiences longer days and warmer temperatures, beginning in the spring. When the south is tilted toward the Sun, then the southern hemisphere generally experiences the warmer weather.

As the earth revolves around the sun there are two moments (not whole days) of the year when the Sun appears exactly above the equator. At these times neither pole tilts toward the Sun. These moments are called "equinoxes". One occurs in March as the northern hemisphere starts to tilt toward the sun. In the north, that equinox is called the "vernal" or spring equinox, the beginning of spring. The other, in September, is the autumnal equinox and is the first day of fall (autumn). In the southern hemisphere, the March equinox is autumnal, and the September equinox is vernal. Around the time of either equinox (which means "equal night") the daylight period of the day is about the same length of time as the night time period.

Astronomy

The term Vernal Equinox has another meaning in astronomy: the point in the heavens which is the location of the Sun at the moment of the northern vernal equinox. This point is useful as an astronomical marker, but because of something called 'precession' it moves very slowly. At one time this point was called the "First Point of Aries", because it was located just over the boundary of the constellation Aries. It is no longer there.

*The actual distance from the Earth to the Sun is not the cause of the seasons. During the northern winter, the Earth is actually a little closer to the Sun than it is during the northern summer.

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When will the vernal equinox be in 2010

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The vernal equinox is Spring; the autumnal equinox is Autumn [Fall].

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See link for a correct definition of Vernal equinox.

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In the Northern Hemisphere, the vernal equinox is the March equinox, which is the autumnal equinox in the southern hemisphere. (March 20) In the Southern Hemisphere, the vernal (spring) equinox is the September equinox, which is the autumnal equinox in the northern hemisphere (Sept 22 or 23).

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Equinox happens twice a year. The Vernal equinox is also called the Spring equinox in the Northern Hemisphere. The 2014 Vernal equinox was on March 20, 12:57 P.M. EDT.

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When the sun reaches the vernal Equinox, Spring begins.

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The vernal equinox marks the beginning of Spring in the Northern hemisphere.

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The vernal equinox marks the beginning of spring, on or around March 21st.

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After the Vernal Equinox the days get shorter as winter approaches.

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The "vernal" equinox is the one on March 21, and is referred to by that label everywhere.

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Because that's how the weather happens to be on that particular vernal equinox. There is no correlation with wind.

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Vernal equinox and autumnal equinox

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"Vernal" is Latin for "spring".

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the vernal is in the spring march 21 and the autumnal is September 23

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The spring equinox is the vernal equinox; the fall equinox is the autumnal equinox.

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The autumnal equinox would be the opposite.

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Spring begins at the vernal equinox.

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For a vernal equinox, it occurs is March 20th. For an autumnal equinox, it occurs September 22nd.

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The vernal equinox is also known as the spring equinox.

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At around 10,500 B.C the vernal equinox is thought to have been in Leo. In astrology this is called the Age of Leo.

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Vernal Equinox on 21st March Autumn Equinox on 21st October

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On March 20 for the Northern Hemisphere (this is the autumnal equinox in the Southern Hemisphere). The vernal equinox for the Southern Hemisphere will be either September 22 or 23.

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the hemisphere that will experience there vernal equinox is the southern hemisphere because in the northern hemisphere will experience autumnal equinox and it is the opposite.

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There is nothing about the vernal equinox which is an intrinsic source of headaches. I could hypothesize that there is something you do in celebration of the vernal equinox that is not good for you, or alternatively, your mere expectation of having a headache at that time of year is enough to cause a psychosomatic headache.


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