Dear Irv and Calendar People,
On 3/20/09, Irv Bromberg <
irv.bromberg@...> wrote:
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>
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> On 2009.03.19, at 19:56 , Brij Bhushan Vij wrote:
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> However, Vernal Equinox is the point in time when SUN is directly over head and causing EQUAL 12-hours in TWO hemispheres of Earth.
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> The only way that you'll reckon a 12-hour day and 12-hour night on the day of the vernal equinox is if you use an equatorial sundial to reckon the time!
How do you figure? Atmospheric refraction certainly impacts sundials.
I suspect the ancients may have used another method for determining
when the equinox occurred: the angle of the path of the sun above the
horizon varies with the seasons. The maximum and minimum occur at the
solstices. Exactly half way (not in terms of time, but in terms of
angle) in between marks the equinoxes.
Victor
Victor
