In the story there are two sister planets the share the same orbit. I want them on the cover. So, the start will be in the background, about the same size as the sun looks from the space shuttle (Google that) and the two planets need to be visible in the foreground. the view of this from the space station is supposed to be 'spectacular'. So the space station is not too close to the planets.
They are earth-like planets, with clouds and such, but different continent shapes of course (shapes don't matter).
Needs to be all original.