Position of Polaris

Krumpe, Andrew (Andrew.Krumpe@NeslabInstruments.com)
Mon, 7 Dec 1998 08:01:04 -0500


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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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I believe that height of Polaris above the horizon is a function only of
latitude and not of the time of year. In other words, at the poles,
Polaris is ALWAYS directly overhead, not only on the equinoxes, but
every day. The same is true no matter where you are. If you're in Boston
(latitude approximately 42 degrees N), then the height of Polaris is
ALWAYS equal to your latitude, or 42 degrees in this case.

Richard Joffee wrote:

90 degrees minus the sun's height above the horizon at noon is your
latitude. It should be directly overhead at the equator and on the
horizon
at the poles. This is only true at the equinoxes (first days of Spring
and
Autumn). I believe the sun's height will vary 23 1/2 degrees above or
below
the latitude, being 23 1/2 degrees above the true latitude at the Summer
Solstice (first day of Summer), and 23 1/2 degrees below at the Winter
Solstice (first day of Winter).

To determine when it's noon without a watch, put a stick in the ground
and
follow the shadow. When the shadow is shortest, it will be noon, and
the
shadow will point to true North.

Extra credit: You may also use the height of the North Star (Polaris)
above
the horizon. It should be directly overhead (90 degrees) at the North
Pole
on the equinoxes, and on the horizon at the equator. On any other day,
you've have to make an adjustment.

Richard D. Joffe
rdjoffe@erols.com
P-15 #2080, "Potter Noster"
Columbia, MD

P.S. I'm late on reading my e-mail, so someone else may have already
rung in
before me, and no, Alex, I didn't phrase the answer in the form of a
question. :-) (Jeopardy joke)