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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsSun over Earth’s equator at equinox
The 2016 autumnal equinox for the Northern Hemisphere (spring equinox for the Southern Hemisphere) will take place on Thursday, September 22, at 14:21 UTC. At this special moment the instant of the September equinox the midday sun is at zenith, or straight overhead, as seen from Earths equator. Thats the meaning of equinox. The September equinox sun crosses the skys equator, going from north to south.
http://earthsky.org/tonight/sun-over-earths-equator-at-equinox
Botany
(70,588 posts)Botany =
elleng
(131,129 posts)(GMT) but is now referred to as Coordinated Universal Time or Universal Time Coordinated (UTC). It is a coordinated time scale, maintained by the Bureau International des Poids et Mesures (BIPM). It is also known as "Z time" or "Zulu Time".
the midday sun
Everyone along Earths equator on the day of the equinox and for a day or two before and after it will experience that noonday sun more or less overhead.
Bucky
(54,068 posts)It's CUT time, baby!!
elleng
(131,129 posts)HAHA! Gotta find out what my Aussie friend has to say!
muriel_volestrangler
(101,367 posts)It's EST that is 5 hours different.
Botany
(70,588 posts)n/t
jberryhill
(62,444 posts)But not "EDST"
EST is Eastern Standard Time
EDT is Eastern Daylight Time.
Sacrifice one goat at 9:21 and another at 10:21 and you can't miss.
Botany
(70,588 posts)LuvLoogie
(7,034 posts)I'll be drinking mead with the maidens.
Lochloosa
(16,068 posts)canetoad
(17,190 posts)And I think of a day in early August 2015, walking the dogs on the beach as we do daily, there seemed to be a change in the air. The wind was almost imperceptibly warmer, or less chilly at least. It occurred to me that we may be at the mid-point between the winter solstice and the spring equinox.
Sure enough, by counting weeks and days I discovered that we were indeed exactly half way but also discovered on the web that these days are called 'Cross Quarter Days' and are an integral part of ancient and wiccan calendars.
Astronomy 161:
An Introduction to Solar System Astronomy
Prof. Richard Pogge
Further Notes on Cross-Quarter Days
You will no doubt have noticed that our current dates of celebration of these holidays are not exactly on quarter or cross-quarter days. This is because these holidays were fixed in the calendar during the late-Middle Ages, whereas in the more distant past their coming was often marked by observing (or at least estimating) the occurrence of a particular station of the Sun along the ecliptic (i.e., observing the arrival of the Solstice or Equinox). Sites like Stonehenge in the UK are believed to be examples of such "observatories". The 4-fold divisions of the Solar ritual year on the cross-quarter days are visible in many ancient megalithic monuments, as well as being encoded in the Celtic Calendar of Coligny from the 2nd century AD. The Maya in Central America, and the Native Americans at the Cahokia mounds near St. Louis created similar "solar observatories" in their city/temple complexes, which were laid out on strict astronomical lines. The approximate dates we use today reflect half-remembered astronomical traditions that are older than our familiar calendars.
The Celtic Solar Calendar and traditional Japanese Luni-Solar Calendars used the cross-quarter days to mark the start of the various seasons, unlike the current tradition in the West where we say speak of the Equinoxes and Solstices proper as the first day of their respective season. The Celtic and traditional Japanese usages are actually more astronomically correct, at least for the latitudes of those societies. For example, in the traditional Japanese calendar the first day of spring (Risshun) is on the first cross-quarter day (Feb 3 or 4 - time of the traditional Setsubun festival which used to mark the beginning of the new year), Summer begins on May 6 (Rikka), autumn on August 8 (Risshuu), and winter on November 7 (Ritou).
In 2007, the approximate times of the cross-quarter days are as follows (all times are UTC):
1st CQD 2007 Feb 4 05:18 UTC
2nd CQD 2007 May 5 21:21 UTC
3rd CQD 2007 Aug 7 21:31 UTC
4th CQD 2007 Nov 7 19:24 UTC
http://www.astronomy.ohio-state.edu/~pogge/Ast161/Unit2/crossquarter.html
elleng
(131,129 posts)'But oddly enough in Australia we take little note of the actual Equinox in declaring seasons.
We mark the arrival of Spring on 1st September, Summer 1st December, autumn 1st March and winter 1st June.'
canetoad
(17,190 posts)Makes it easy doing financial bookwork