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?

On Feb 22, 10:26�am, 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?

My logic would agree with your logic, but I'm not completely informed
about all of the specific characteristics.

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.

On Thu, 22 Feb 2007 20:13:10 GMT, Short Wave Sportfishing
wrote:

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.

I understand your point if taking a distant view from outer space.

At close range however the moon is revolving around the earth, and the
earth is spinning on its axis. That says to me that the geographic
position of the barycenter is constantly shifting with respect to the
earth's surface.

"Wayne.B" wrote in message
news

I understand your point if taking a distant view from outer space.

At close range however the moon is revolving around the earth, and the
earth is spinning on its axis. That says to me that the geographic
position of the barycenter is constantly shifting with respect to the
earth's surface.


"It" doesn't shift. It's just never in the same place.

Eisboch :-)

Wayne.B wrote:
On Thu, 22 Feb 2007 20:13:10 GMT, Short Wave Sportfishing
wrote:

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.

I understand your point if taking a distant view from outer space.

At close range however the moon is revolving around the earth, and the
earth is spinning on its axis. That says to me that the geographic
position of the barycenter is constantly shifting with respect to the
earth's surface.

Hmmmm - I guess you could put it that way in terms of geography. You
could also say that the Earth is spinning around the barycenter.

For example, it you had two bodies on the same plane orbiting each
other, the barycenter is located in space between the two - it doesn't
move as long as the masses are balanced by the mechanical motion.

Or take another case. Say you have a large rotating body around which a
smaller, but massive body rotates. The barycenter is just above the
surface of the larger body. The barycenter never changes position - it
is the balance point, but the structure below it changes.

Good God, I haven't worked with these concepts in ages. I have a
headache. :)

On Fri, 23 Feb 2007 01:42:23 GMT, Short Wave Sportfishing
wrote:

Good God, I haven't worked with these concepts in ages. I have a
headache. :)

Sorry I made your head spin.

But wait, it was already spinning...

No sympathy here. I've been reading Isaac Asimov's "Asimov on
Physics" in my spare time. It is an incredibly lucid and readable
account of some very esoteric concepts. Published in 1976 but
available used on Amazon.

http://www.amazon.com/Asimov-Physics.../dp/0380418487

Wayne.B wrote:
On Fri, 23 Feb 2007 01:42:23 GMT, Short Wave Sportfishing
wrote:

Good God, I haven't worked with these concepts in ages. I have a
headache. :)

Sorry I made your head spin.

But wait, it was already spinning...

No sympathy here. I've been reading Isaac Asimov's "Asimov on
Physics" in my spare time. It is an incredibly lucid and readable
account of some very esoteric concepts. Published in 1976 but
available used on Amazon.

http://www.amazon.com/Asimov-Physics.../dp/0380418487

It's in my library - autographed no less. :)

Did I ever tell you the story of how I met him?

On Fri, 23 Feb 2007 13:07:10 GMT, Short Wave Sportfishing
wrote:

http://www.amazon.com/Asimov-Physics.../dp/0380418487

It's in my library - autographed no less. :)

Did I ever tell you the story of how I met him?

No, please do, one of my childhood heros just to show how geeked up I
was.