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Re: Measuring acceleration of Earth



If you weigh something very accurately, at the equator, and at both Noon and
Midnight, I get that there should be about a .003% difference due to the
relative speed difference in the v^2/R term for the earth's motion around
the sun. Perhaps such a measurement could be used?

The difference in speeds is a LOT bigger than that. The orbital
speed of a point at the equator at midnight approaches 31 km/s and at
noon 29 km/s. This creates a real diurnal variation in what would be
observed as the the magnitude of the gravitational field strength.
However, it's easy to show that the magnitude of the variation is no
more than 8 angstroms/s^2, about 1 part in 10^10, so measuring it
would certainly be at least VERY difficult.

John Mallinckrodt
Cal Poly Pomona