CompuServe Messages

I'm new to 3DS, so please forgive the ignorance. I'm trying to animate the moon orbiting the earth, while the earth is orbiting the sun. I place all three objects in position in the 3D Editor. I create a large ellipse in the 2D Shaper and assign it as a path in the Keyframer to the earth. I create a smaller ellipse in the 2D Shaper and assign it as a path in the Keyframer to the moon. I then link the moon to the earth, but when I do this I screw up the earth's path around the sun. I want the moon to follow an ellipse around the earth, which is following an ellipse around the sun. Can I do this? How? Thanks for the help. Dirk