Thursday 26 December 2013

Equinox and solstice info
For Your Book of Shadows: 2014 Equinoxes and Solstices

A solstice is an astronomical event that occurs twice each year as the Sun reaches its highest or lowest excursion relative to the celestial equator on the celestial sphere. As a result, on the day of the solstice, the Sun appears to have reached its highest or lowest annual altitude in the sky above the horizon at local solar noon.

An equinox occurs twice a year, when the plane of the Earth's equator passes the center of the Sun. At this time the tilt of the Earth's axis is inclined neither away from nor towards the Sun. At an equinox the Sun is at one of two opposite points on the celestial sphere where the celestial equator (i.e. declination 0) and ecliptic intersect.

The solstices, together with the equinoxes, are connected with the seasons. In many cultures the solstices mark either the beginning or the midpoint of winter and summer.

In 2014, the date and time of equinoxes and solstices on Earth are as follows:
Northward Equinox: March 20th at 16:57 UT
Northern Solstice: June 21st at 10:51 UT
Southward Equinox: September 23rd at 2:29 UT
Southern Solstice: December 21st at 23:03 UT


Notes:
(1) Universal Time: Universal Time (UT) is a time standard based on the rotation of the Earth. It is a modern continuation of Greenwich Mean Time (GMT), i.e., the mean solar time on the Prime Meridian at Greenwich, and GMT is sometimes used loosely as a synonym for UTC.
(2) A number of time zone converters is available. Here's one:http://www.timeanddate.com/worldclock/converter.html
(3) Northward Equinox and Southward Equinox: Names referring to the apparent motion of the Sun at the times of the equinox. The least culturally biased terms.


Sources: U.S. Naval Observatory, NOAA and en.wikipedia

http://www.thesmartwitch.com/

[Image: A solargraph taken from the Atacama Pathfinder Experiment (APEX) at the Llano de Chajnantor Observatory in the southern hemisphere. This is a long-exposure photograph, with the image exposed for six months in a direction facing east of north, from mid-December 2009 until the southern winter solstice in June 2010. The Sun's path each day can be seen from right to left in this image across the sky; the path of the following day runs slightly lower, until the day of the winter solstice, whose path is the lowest one in the image. APEX is a collaboration between the Max-Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO) and the European Southern Observatory (ESO). The telescope is operated by ESO. Authors: R. Fosbury, T. Trygg and D. Rabanus.http://www.eso.org/public/images/potw1039a/

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