The Solstice and Tilt of the Earth
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For thousands of years, people have practiced rituals which got their cues from the heavens: cues like the rising and setting of the sun and stars, eclipses, planetary alignments, comets, moon phases, and meteor showers.
One pattern the ancients would notice was that every year, during the
winter months, the sun would start rising and setting farther north each
day and traverse across the sky higher and higher. Daylight would last
longer and the days would get warmer.
But this pattern would mysteriously stop after several months. For some
reason that day would come when the sun would not rise and set any farther
north nor sweep any higher overhead in the sky. On the contrary, it would
reverse its daily trend into wintertime, when the whole cycle started
all over again.
A special name was given to the day when the sun hit its high mark in
the sky. It was christened "solstice," which loosely translated
means "the sun has stopped." Early astronomers/astrologers -
back then they were one and the same - noticed that the solstice always
happened when the sun was vacationing in the constellation Cancer the
Crab. (Now it occurs when the sun is in Taurus.)
People who happened to be about 23 degrees north of the equator on the
summer solstice - like in ancient Syene, Egypt - would discover that they
were standing directly over their shadow. The sun was directly overhead.
This special latitude on Earth, 23.5 degrees N, was given the name Tropic
of Cancer. Anyone living north of this imaginary line would never see
the sun directly overhead because for some reason the sun never traveled
that far north.
Now
fast-forward to the present.
We now know that the sun teases us this way because Earth is a little
tipsy - it’s tilted over by about 23.5 degrees. (This is the reason
those globes in stores are always tipped to one side.)
We in North America are tilted most toward the sun on June 20, so the
sun rises as high above our heads as it can on that day. Take the family
outside around noon on that day and see what’s left of your shadow.
It won’t be getting any shorter.
The Tilt is one of those classic taken-for-granted things about our planet.
Our perfect tilt allows a massive amount of earth’s surface to get
some nice, moderate year-round temperatures - not too hot, not too cold.
There is a huge area of comfortable living space available.
If we weren’t tilted at all, the only comfortable places to live
would be near the equator. The frozen Arctic Zones, north and south, would
be much bigger.
If we were tilted more, our summers would be more severe, our winters
more treacherous and, again, the best places to live would be near the
equator.
In a cosmic version of The Three Bears, we might say with Goldilocks that
our tilt is not too great, not too small: it appears our tilt is just
right.
Until next time, clear skies and sunny solstice!
Posted by Administrator at 2000.06.11 09:31 AM | Comments (0)
