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Old 03-09-2004, 04:32 AM
Scott Anderson
 
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Yes, days and nights are always the same (almost) on the equator. But
the sun is not always directly overhead on the equator. It's only
directly overhead on the spring and autumn equinoxes. Any other time
it appears to be swinging north and south between the tropics.

Technically, the earth and sun really aren't tilting north and south
each year. The earth rotates at an angle relative to the plane of it's
orbit. The poles don't rotate around the sun, rather they stay pointed
in the same direction, no matter where the earth is in it's orbit. In
June, the north pole is pointed a little bit towards the sun and it's
the northern hemisphere that gets longer days. In December, the Earth
has gone 180 degrees around it's orbit, but because the poles don't
rotate, they are still pointed in the same direction and now the south
pole is pointed towards the sun and it's the southern hemisphere that
gets longer days. From the point of view of an observer on the earth,
this causes the path of the sun to swing north and south over the
course of the year as the planet swings around it's orbit. There's an
illustration of this he

http://www.crh.noaa.gov/fsd/astro/season.htm

And an explanation he

http://www.synapses.co.uk/astro/sunpath.html



On Fri, 03 Sep 2004 02:18:00 GMT, "Jim Carlock"
wrote:

....

Okay, my question is this... if you live on the equator,
are the days and nights equal every day of the year?
http://puuoo.submm.caltech.edu/outre...ay/sunrise.htm

If the sun is always directly above the equator, and the
equator represents the closest portion of the earth to the
sun, how does the sun cross the equator? You lost me
with your statement. I think you meant to say something
else.

http://www.equinox-and-solstice.com/..._solstice.html

The link above indicates that the longest day of the year falls
on or about June 22 (at least for the northern hemisphere). It
should be December 22 for the southern hemisphere. So with
Dec 22 being the longest day for the southern hemisphere and
Dec 22 being the shortest day for the northern hemisphere...
does any of this matter on the equator, being that on the
equator, you'd get 12 hours of day and 12 hours of night
each and every day of the year, because you'd be on the
closest spot on earth to the sun, each and every day of the
year, not taking mountains and depressions into consideration.

Being that the earth rotates on an axis, the autumnal equinox
I think is going to vary slightly for every every position away
from the equator? I think that's the lattitude.

There is a great link here that talks about how the distance of
the earth from the sun never goes past 3% or 4% and states
that the earth is more circular in orbit than elliptical. I used to
think that the distance from the sun is what caused seasons
when I was a kid. That's not true. The link below indicates
that the earth is farthest from the sun on or about July 4th.
Very interesting coincidence!
http://liftoff.msfc.nasa.gov/news/20....asp?list17366

Thanks for the comment, I think I know what you're trying
to say, but you are just not saying it correctly. ;-)