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## Main Question or Discussion Point

I can find public information about the speed of the moon at max and min distance from the Earth (Ap vs Per) but how do I find the same information for the Earth's velocity around the same barycentre? The Earth's orbit around the barycentre is it a perfect circle or is it an ellipse? If it's an ellipse should I assumed that when the Moon is at max distance from the barycentre and the Earth that the same is true with the Earth's being at max distance from the said barycentre?

I can find some information about the distances both bodies should be from the barycentre here: https://en.wikipedia.org/wiki/Barycenter

But this assumes a circular orbit and not ellipsoid orbit that the Moon in reality orbits the Earth in. I assume this should also mean the Earth has an ellipsoid orbit around the same barycentre. Also this article gives no hints about the Earth's velocity at all around said barycentre.

How do I find out Earth's velocities at either extreme (Ap vs Per) of it's presumed ellipsoid orbit around the barycentre?

David

I can find some information about the distances both bodies should be from the barycentre here: https://en.wikipedia.org/wiki/Barycenter

But this assumes a circular orbit and not ellipsoid orbit that the Moon in reality orbits the Earth in. I assume this should also mean the Earth has an ellipsoid orbit around the same barycentre. Also this article gives no hints about the Earth's velocity at all around said barycentre.

How do I find out Earth's velocities at either extreme (Ap vs Per) of it's presumed ellipsoid orbit around the barycentre?

David