Showing posts with label spaceship earth. Show all posts
Showing posts with label spaceship earth. Show all posts

Tuesday, January 6, 2009

Spaceship Earth

I have been hearing for most of my life a few terms about our planet that make no sense to me, probably because I paid no attention when someone tried to teach me . I am referring to Equinox and Solstice, the planetary behaviors, not the names of the teachers to whom I paid no attention. I have a vague recollection that Disney, too, may have tried to teach me this as I rode thru spaceship earth in Epcot, but I was much more interested in hollering "wooooo-hoooo, this is awesome" than in paying attention to the disembodied voice that was trying to educate me.


As I have recently remedied my ignorance (only in this specific area), I would like to share what I have learned…before I forget it, which will likely occur very soon.

First, equinox. If we grab the “equi” part, which is derived from "equs", “equal”, it’s easy to remember the meaning. Twice a year, during the earth’s trip around the sun, the tilt of the Earth’s axis will be neither toward nor away from the sun. At this point, we have equal amounts of daylight and darkness. One time is in the spring, and one time is in the fall. The spring is the vernal equinox, the fall is the (duh) autumnal equinox. Vernal, by the way, comes from the latin "ver", spring. How 'bout that...
Solstices are the other extremes from the equinoxes. During the solstices, the relative tilt of the earth’s axis is at its extremes. The result is that at the summer solstice, we have the greatest amount of daylight and at the winter solstice we have the least amount of daylight.

At this time, those of you who are versed in astronomy are rightfully incensed that I have skipped about 99% of the science that explains all this. You are correct. I have elected not to attempt explaining that science because it made my brain hurt. I will, however, throw in some cocktail party factoids that I encountered along the way.

The earth rotates on an imaginary axis that is tilted at 23.44 degrees.
The tilt varies between 22.1 and 24.5 degrees.
The tilt is why we have seasons.
These solstices and equinoxes are instantaneous, fleeting points in time.
The earth rotates on its axis. The earth revolves around the sun.
The orbit of the earth (revolution) is elliptical.
The earth is moving through space at 67,000 miles per hour.
The orbit takes 365.26 days. That .26 necessitates the leap year adjustment.
We just had the winter solstice on December 21.

In 2009, the vernal equinox will occur March 20, and summer solstice will occur June 20th, at one minute to midnight.

My brain is starting to hurt again, so it is time to stop.