Wayne.B wrote:
On 22 Feb 2007 07:38:11 -0800, "Chuck Gould"
wrote:

In the interest of sustaining this worthwhile feature in the NG, I
offer:

barycenter (n): A theoretical point 810 miles below the surface of
planet Earth. This point is the rotational center of the Earth and
Moon. The gravitational attraction between Earth and Moon affect the
oceans and their tides; centrifugal forces result from their
revolutions around the barycenter.

( above definition by Lenfestey/Lenfestey)

The barycenter is a definite consideration when examining the physics
of tides, particularly the standing wave on the side of Earth opposite
the position of the moon.

Logic tells me that the barycenter must be constantly moving to match
the current location of the moon.

Is that correct?

No. It induces a wobble in the larger object. That's how NASA, Ames
and JPL do those extra solar planet searches with the Spitzer X-Ray and
Hubble telescopes - they look for the star wobble and aim for where the
planet should be based on the arc of the wobble.

The barycenter is the barycenter - the center of mass of any system of
objects.

Center of gravity is another whole subject.