Pete, the essence of the semantic confusion is not whether the moon is doing things, which it certainly is, but whether it is not doing particular things (things that it is in particular doing in point of fact!)

Your ball (and the moon) are describing trajectories that are not centred on their respective axes. No argument. But the question was not whether they are doing such things, which is common cause, but whether they are in fact doing what pon denies, namely rotating round their own axes as well, which is what I assert.

If the ball (and moon) are not rotating round their own axes (while doing other things, to be sure) then nothing is rotating round its own axis, because everything in the universe is describing trajectories that do not coincide with its stationary axis. So for example, do I deny that a top is spinning because it wanders over the ground once I have thrown it? Do I deny it wanders? Of course not; I can see it wandering? Pon could hardly in good faith or good sense deny that it spins as well!

What might be the criterion for "spinning round its axis"? How about the fact that it keeps presenting different aspects to (notionally stationary) me  (meaning I do not move from my point of view) on a well-defined schedule consistent with a consistent (or decaying of course) angular momentum. (Like the moon of course.) Is its movement perfect? Of course not (Like the moon of course.)

Do I give the impression of spinning as i present that claim? Well then, try this old chestnut:

Fix a coin to a flat surface, say a bob. Now put another bob down in tangent contact with the fixed coin, and rotate the loose coin like a cog around the fixed coin, without slippage or loss of contact. If you have two matching cogs (possibly Meccano or Lego) of equal size and matching teeth, you might prefer to use them instead. Continue the rotation till the loose cog or coin is back where it started. How many rotations has the loose coin undergone? And were those rotations relative to its axis or not?

Am I getting through?

Cheers,

Jon

I'm fully in agreement with you Jon. I was just playing devil's advocate because I can see what Mr P was trying to say. My point is that he seems to understand the manner by which the moon circles the earth, so whether he chooses to call it spinning, rotating, circulating or just revolving is up to him. If he asserted that the moon is stationary and that the rest of the universe revolves around it, then we'd have cause to jump on him.

OK, Pon, Pete, and Ped, in alphabetic sequence; to quote someone else, if I think too deeply on such things the world starts going round on me...

Thanks for your respective thanks, advocacy, and bobbing. When it is New Moon again, I'll go out and stare at it to clear my mind on the subject.

Or maybe I had better not...