Earth is Moving Proof
Name: Greg Capelle
Date: Around 1999
How would you prove to someone that the earth is moving?
One of the simplest ways is to use a Foucault Pendulum. This is a long
pendulum (small angular swing) in relatively low friction circumstances.
Once it is set swinging, the plane of swing appears to shift relative to
the room over time. The rate of shift is a function of latitude. At the
poles of rotation, it takes about 24 hours for one complete shifting of the
plane. As you move away from the poles of rotation toward the equator, the
period of a complete 360 degree shift increases. Many museums have such a
pendulum on display.
Other proofs are more subtle. This includes Coriolus Effect that is found
in weather systems and ocean circulations, and Doppler measurements that
can be made.
Nathan A. Unterman
The best way to answer this I think is to just look at how this was all
done. It took alot of arguing for hundreds of years. You can always come up
with an explanation of how the earth is moving, the sun is moving, the
planets etc, and keep the earth at the center of it all. But the explanation
gets more and more complicated, circles inside of circles. Along comes
Copernicus (spell?) and Kepler in the 1500's and they have a simpler model.
But does that make it the "correct" model? It took a while. So while there
are ways to make it clear that the earth is moving, someone can always argue
I read all this once in a book called The Ascent of Man, by Jacob Bronowski
(spell?), it was also a PBS TV show, and your library may have the tapes.
Its pretty easy to find this story written down.
If the person believes in gravity, show them the sun and point out the
fact that we are not in the middle of it. There's a gravitational
attraction between the earth and the sun, so we must be falling toward
it, yet we never get there. This must be because we are moving
sideways and falling toward the sun at the same time.
If the person doesn't believe in gravity, ask them to hop.
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Update: June 2012