Sunday, February 08, 2009

Times Solstices & Equinoxes 2000-2010

Times Solstices & Equinoxes 2000-2010: "
Vernal Equinox Mar 20 2009 7:44 AM EDT
Sumer Solstices Jun 21 2009 1:45 AM EDT
Autumnal Equinox Sep 22 2009 5:18 PM EDT
Winter Solstice Dec 21 2009 12:47 PM EST

Vernal Equinox Mar 20 2010 1:32 PM EDT
Summer Solstice Jun 21 2010 7:28 AM EDT
Autumnal Equinox Sep 22 2010 11:09 PM EDT
Winter Solstice Dec 21 2010 6:38 PM EST"

The Vernal Equinox Explained

The March equinox, which was on March 20 in 2008, occurs on the same date but at a different time in 2009. It is also called the vernal equinox in the northern hemisphere and marks the beginning of spring in some cultures and falls around the Easter period. The March equinox occurred at 05:48 (or 5.48am) at Coordinated Universal Time (UTC) on March 20, 2008. However places that are six hours or more behind UTC observed the March equinox as early as March 19. The March equinox will occur at 11:44 (or 11.44am) UTC on March 20, 2009.


This illustration, which shows an example only of the March equinox, is not to scale.

What does equinox mean?

In the northern hemisphere the March equinox is referred to as the spring or vernal equinox. In the southern hemisphere it is referred as the autumnal or fall equinox. The word “equinox” derives from the Latin words meaning “equal night” and refers to the time when the sun crosses the equator. The word “vernal” means “spring” in Latin.

March Equinox Explained

Twice a year, around March 20 or 21 and September 22 or 23, many regions around the equator have a daylight length about 12 hours and six-and-a-half minutes during the equinox. These two days are known as the March equinox and the September equinox.

The March equinox occurs on a day when the sun crosses the true celestial equator – or the line in the sky above the earth’s equator – from south to north. It occurs annually around March 19 to March 21 depending on the year in the Gregorian calendar. At that time, the earth’s axis of rotation is perpendicular to the line connecting the centers of the earth and the sun.

The point of intersection of the ecliptic, inclined from south to north, and the celestial equator is called the true vernal equinox. In gyroscopic motion, the earth’s rotational axis migrates in a slow circle based as a consequence of the moon’s pull on a nonspherical earth. This nearly uniform motion causes the position of the equinoxes to move backwards along the ecliptic in a period of about 25,725 years.

Nearly Equal?

During the March equinox, the length of night and day across the world is not entirely equal. This is because the day is slightly longer in places that are further away from the equator and the sun takes longer to rise and set in these locations. Furthermore, the sun also does not set straight down, but it also moves in a horizontal direction.

During the March equinox, the length of daylight is about 12 hours and eight to nine minutes in areas that are about 30 degrees north or south of the equator, while areas that are 60 degrees north or south of the equator observe daylight for about 12 hours and 16 minutes. Many regions around the equator have a daylight length about 12 hours and six-and-a-half minutes during the March equinox.

Moreover, one day does not last for an exact 24 hours across the world and due to time zone differences, there could be a few small minutes’ difference between a far-eastern and far-western location on the same latitude, as the sun moves further north during 24 hours. For more information, click here to find out the length of day in a particular city. Select a location in the drop-down menu below to find out the length of day on March 20, 2008.

Historical Fact

A Greek astronomer and mathematician named Hipparchus (ca. 190-ca.120 BCE) was known for discovering the precession of the equinoxes, the slow movement among the stars of the two opposite places where the sun crosses the celestial equator. Hipparchus made observations of the equinox and solstice.

Astronomers use the spring equinoctial point to define their frame of reference, and the movement of this point implies that the measured position of a star varies with the date of measurement. Hipparchus also compiled a star catalogue, but this has been lost.

Useful Tools

To calculate the approximate time and date (according to Coordinated Universal Time) of the March equinox, as well as the June and December solstices and the September equinox, click on the Seasons Calculator. These dates mark the beginning of the four seasons of the year, which are spring, summer, autumn (or fall) and winter. It is important to note that the seasons in the northern hemisphere are opposite to those in the southern hemisphere. Click here for more information about the Seasons Calculator and links to useful tools, such as the Day and Night World Map, Moon Calculator, Moon Phase Calculator, and Sunrise Calculator.

The World Clock can also be used to find sunrise and sunset times, as well as the current position of the sun in major cities around the world. Simply select any location that is available from the World Clock and the calculator will adjust the local time in that particular city.

March Equinox across Cultures

In the northern hemisphere the March equinox marks the start of spring and has long been celebrated as a time of rebirth. Many cultures and religions celebrate or observe holidays and festivals around the time of the March equinox, such as the Easter holiday period.

The astronomical Persian calendar begins its New Year on the day when the March equinox occurs before apparent noon (the midpoint of the day, sundial time, not clock time) in Tehran. The start of the New Year is postponed to the next day if the equinox is after noon.

Astronomy calculators

More information

Calendar tools

Related time zone tools



Thank You Jesus Christ for Creating The Way of Your Word!

I Love You Dearest Loving Lord Jesus Christ.

at 9:19 PM

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)