Thread: The Equinox
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Old March 19th 09, 10:27 AM posted to uk.sci.weather
Dave Liquorice[_2_] Dave Liquorice[_2_] is offline
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Default The Equinox

On Thu, 19 Mar 2009 09:54:40 -0000, Philip Eden wrote:

is 18.12.ie a difference of 12 hours 7 minutes. If the equinox is not
until the 21st, how come ?


Refraction, Ron. You know that when you put a knife half in
and half out of a glass of water the knife looks as though it's bent
at the boundary of the air and the water. Same thing happens in
the atmosphere.


Is it purely that? I had an idea that it was to do with ones latitude and
the way the curved terminator of the sun light moves across the spherical
surface of the earth. "Equation of time" is the thing to plug into google,
I must do that sometime and try and get my head around what is going on
with the equinox, day lengths and when sunrise/sunset happen.

--
Cheers
Dave.