Autumnal Equinox Today?...Not

[+Greenjeens]

The sun/moon info on my Garmin GPS unit indicates the sun rose at 7AM and sets at 7PM today. I'm on the west coast USA. Think I uncovered part of the reason why the sun rise/set times don't coincide the true Equinox. Something about what point on the sun is measured in rising or setting.

Apparently consumer GPSr aren't very good at predicting celestial events (ooops), let alone a exact physical locations.

Anyone else have more of a clue on this disparity?

 

Autumnal Equinox brief

"A minor point ... if you look up the rising and setting time of the Sun in the newspaper, it'll look as if the day is still a bit longer than the night. That's mostly because "sunset" and "sunrise" are defined by the top edge of the Sun, not the middle of it, and the middle of the sun sets (rises) a few minutes before (after) the edge does"

http://marple.as.utexas.edu/~ideas/equinoxdoc.html

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Greenjeens

[+Zahrim]

quote:

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Originally posted by Greenjeens:

The sun/moon info on my Garmin GPS unit indicates the sun rose at 7AM and sets at 7PM today.

 

Autumnal Equinox brief

"A minor point ... if you look up the rising and setting time of the Sun in the newspaper, it'll look as if the day is still a bit longer than the night. That's mostly because "sunset" and "sunrise" are defined by the top edge of the Sun, not the middle of it, and the middle of the sun sets (rises) a few minutes before (after) the edge does"

http://marple.as.utexas.edu/~ideas/equinoxdoc.html

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Greenjeens

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The Equinox is not related to a 12 hour day. The Merriam-Webster definition is this....

 

Main Entry: equi·nox

Pronunciation: 'E-kw&-"näks, 'e-kw&-

Function: noun

Etymology: Middle English, from Middle French or Medieval Latin; Middle French equinoxe, from Medieval Latin equinoxium, alteration of Latin aequinoctium, from aequi- equi- + noct-, nox night -- more at NIGHT

Date: 14th century

1 : either of the two points on the celestial sphere where the celestial equator intersects the ecliptic

2 : either of the two times each year (as about March 21 and September 23) when the sun crosses the equator and day and night are everywhere of equal length

 

Zahrim....

 

"There's no need to be afraid of strange noises in the night.

Anything that intends you harm will stalk you silently."

[+Zahrim]

quote:

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Originally posted by Zahrim:

quote:

---

Originally posted by Greenjeens:

The sun/moon info on my Garmin GPS unit indicates the sun rose at 7AM and sets at 7PM today.

 

Autumnal Equinox brief

"A minor point ... if you look up the rising and setting time of the Sun in the newspaper, it'll look as if the day is still a bit longer than the night. That's mostly because "sunset" and "sunrise" are defined by the top edge of the Sun, not the middle of it, and the middle of the sun sets (rises) a few minutes before (after) the edge does"

http://marple.as.utexas.edu/~ideas/equinoxdoc.html

----------

Greenjeens

---

 

The Equinox is not related to a 12 hour day. The Merriam-Webster definition is this....

 

Main Entry: equi·nox

Pronunciation: 'E-kw&-"näks, 'e-kw&-

Function: noun

Etymology: Middle English, from Middle French or Medieval Latin; Middle French equinoxe, from Medieval Latin equinoxium, alteration of Latin aequinoctium, from aequi- equi- + noct-, nox night -- more at NIGHT

Date: 14th century

1 : either of the two points on the celestial sphere where the celestial equator intersects the ecliptic

2 : either of the two times each year (as about March 21 and September 23) when the sun crosses the equator and day and night are everywhere of equal length

 

Zahrim....

 

"There's no need to be afraid of strange noises in the night.

Anything that intends you harm will stalk you silently."

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If you happen to live on the equator, then you would have a 12 hour day/12 hour night. If you do not live on the equator, then when the equinox happens at the equator, it will not be 12/12 anywhere else in the world above or below the equator, though it may be close to that.

 

Zahrim....

 

"There's no need to be afraid of strange noises in the night.

Anything that intends you harm will stalk you silently."

[+Greenjeens]

OK, so the big E "Equinox" is a celestial event viewable from where, equator, space, virtually?

What about my local day and night being of equal lengths? Still good for a notch on the local "sun god monolith" or sacrificing a virgin? I was just hoping this darned gps sun/moon sw upgrade could provide some fun info.

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Thanks, Greenjeens

 

quote:

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Originally posted by Zahrim:

The Equinox is not related to a 12 hour day. The Merriam-Webster definition is this....

 

Main Entry: equinox

Pronunciation: 'E-kw&-"nks, 'e-kw&-

Function: noun

1 : either of the two points on the celestial sphere where the celestial equator intersects the ecliptic

2 : either of the two times each year (as about March 21 and September 23) when the sun crosses the equator and day and night are everywhere of equal length

Zahrim

 

If you happen to live on the equator, then you would have a 12 hour day/12 hour night. If you do not live on the equator, then when the equinox happens at the equator, it will not be 12/12 anywhere else in the world above or below the equator, though it may be close to that.Zahrim....

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