Hi,

The problem is in regard to the layer your object is on. That is, if you
place a planet above the earth, it will just sit on top. You need two. One
to go half way on the top layer (right click, Order and bring to top). Then
it needs to disappear exactly when object 2 appears (in the same location as
the one that disappears). Then it is set to the back Order and continues.
Hard work, although not impossible. So, right click on an object and find
the "Order" menu.

Parto,

the Moon is only moving in circles if watched from the Earth.  If you have a
look from outside, as you do in your model, the circular movements of Earth
and Moon are combined to a spiral movement of the Moon.  Use the freeform
motion path to draw it - but it might require some time to get it working
perfectly.

Best regards,
Ute

Hi Parto

My guess is you're gonna find this near impossible with just motion paths.
As Ute says it is a spiral but its damn complicated!

Why not make the Earth and moon an animated gif and then use a motion path
on that . If you would like a sample drop me an email at john "AT SIGN"
technologytrish.co.uk