I have previously reported that I stuck a pipe in the ground
and aimed it at the sun at high noon on an Equinox. It was
aimed by simply positioning it to cast no shadow.
I have been learning and discovering many things with that
simple stick. I'm sure this is all elementary to many of you
but because I never studied any of this in school I find it
great fun in figuring these things out.
With this simple stick I determined:
1. By marking the shadows it works as a solar clock.
2. The day to day differences of the noon shadow allowed me
to make a solar calendar and how many days make one year.
3. The front to back direction of the pipe gives me a line
of true north/south and with that information I determined
an accurate east/west without a compass.
4. The daily noon time shadows allowed my to determine the
Solstices, without a calendar, when the shadows reversed
directions.
5. I was able to determine my latitude by measuring the
angle of the stick from plumb.
6. I could visually grasp the equatorial plane by looking at
my stick from east or west.
7. I could get a good sense of the where the Earths' poles
were by visualizing another stick at a right angle to my stick.
8. I noticed that sometimes my stick points close to the
moon when it passes overhead. I'm curious to see if the moon
is directly in line with my stick on the equinox, if so it
is in the same plane as the earth. I think by careful
observation I could determine if the moon was a moon or a
planet orbiting the sun.
9. I notice also some "stars" that are bright at dawn and
dusk and also pass very close to the aim of my stick. I
think by careful observation I could determine if these are
orbiting the sun, and thus they are not stars or moons but
planets. I'm also curious to see if they line up exactly
with my stick on an Equinox, which would mean they are on
the same plane with Earth, which I suspect.
10. We are having a Solstice in a week and I think I can set
another stick that aims at the sun at high noon. I think I
can measure that angle between the Solstice stick and the
Equinox stick and determine the tilt of earth's axis.
These are huge concepts that can be determined with no
fancy tools, just a simple stick in the ground. I guess that
this may have been how the ancients started to figure out
our universe, by observing shadows and the changes in the
sky in relationship to the object making those shadows...
our gnomon.
If that's so, astronomy may have started with just a
stick in the ground and someone who had the curiosity to
watch it.
brent
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