15.5 - 19 seconds image development for final animation

I now want the UFO look like its visiting earth where the signals had come from and want to make it look as though its flying in and out and around the earth exploring. 

To make It look convincing that the UFO is flying around earth and flying in and out I had to make the UFO change scale as it flew into the earth and then as it came back out gradually enlarge it.