Need actionscript help with my animation

Hey everybody

I’m new to flash and I was wondering if you guys could help me out. I’m trying to make an animation showing Mars rotating around the earth for a class about old astronomy.

I have Mars going in a circle and then that circle going around the earth already. I did it using automatic tweening rotation and a gotoandplay command at the end of the animations to make them smooth. However, now I need to create a trail showing the path that Mars takes as it travels around the earth. I haven’t been able to figure out how to do it. What I would like to do is every few frames have a new white oval be created directly under Mars, so that as it travels it leaves a dotted white line behind it, showing its path. unfortunately, I can’t figure out how to make a new oval appear in actionscript.

Another solution I tried was to start with one white oval movie clip under mars on the first frame, and then create a duplicate and move it to mars’s new postion every few frames, creating the same effect described above. I looked at the duplicating movie clips tutorial here at kirupa but it didn’t work. I made a trace line saying when the clip is duplicated and printing its x and y coordinates. They print, so it seems like the duplicated clip exists, but I’m not seeing anything on my screen.

I attached an image explaining my animation. If you imagine the line that mars is going to make as it goes in a circle while rotating at the same time, you’ll see what I mean.

BTW, I realize that I could use paths, make the animations graphic objects, and then scrub through the frames drawing in white ovals manually. The problem is that that takes a long time, and I need an animation that shows a specific kind of orbit. So I’d like to be able to tweak my animation (like the speed of rotation, size of mars, etc) without having to redo it every time.

Sorry for the long post and thanks so much. If someone could help me with this it would be a lifesaver.