I cannot confirm this, because it is possible 
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Vector Shape paths can be pasted onto animation motion paths.
Make an elliptical path
- Create an Ellipse element
- Extend it out from a circular shape, because Aristotle Was Wrong™
- Choose Edit > Convert to Vector Shape
- Exit Vector Shape mode, but keep the Ellipse selected
Copy the Vector Shape
- Edit > Copy
Make your planet
- Create a new element
- You will need to give it some sort of animation, such that it has a motion path line
Paste the path
- Click to select the motion path line and double click so it is editing it as a path
- Choose Edit > Paste
Of course, a purely circular animation is much easier with an anchor point.