The refraction of the Earth's atmosphere increases the amount of daylight by
about 2 minutes at sunset and about 2 minutes at sunrise for latitudes below
about 40 degrees. Add to that another minute for the diameter of the sun on
each end and you have a total of 6 minutes added to daylight. But the true
equinox is the same everywhere on the earth and that occurs the instant the
center of the sun passes through the plane of the Earth's equator. This is
0100 GMT on March 21 this year.
Carl Moreschi N4PY
Franklinton, North Carolina
n4py@earthlink.net
----- Original Message -----
From: "Jim Reid" <jimr.reid@verizon.net>
To: <tentec@contesting.com>; "towertalk" <towertalk@contesting.com>
Sent: Saturday, March 15, 2003 7:03 PM
Subject: [TenTec] Equinox Day
> Hi,
>
> Yes, today is equinox day here on the Island of Kauai.
> Sunrise this morning here was at 6:47 AM, HST;
> sunset this evening will occur at 6:47 PM, HST. Thus,
> 12 hours of daylight and 12 hours of time that the Sun
> will be below the horizon.
>
> Why today, and not on/nearer the 21st? Two reasons actually,
> our latitude is only 21.9N and the Earth's orbit about
> the Sun is elliptical, not circular. Actually, the center of the
> Sun is still 2 degrees South of the Equator today.
>
> Anyway, just some trivial info which might be of some interest
> to those also interested in how to find the direction towards
> True North, hi. And, perhaps have something else on their
> minds other than the current World news.
>
> 73, Jim KH7M
>
>
>
>
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