Thank you for your reply,
at first i had the moon filling the left quarter of the screen and the TARDIS going past it towards the earth. Maybe i´ll try that one again.
The real proportions earth/moon were not nice to look at because the difference is huge and one is going to be very small. So i decided to make the moon bigger than it is. Could look better if i rearrange the earth and moon.
On the lighting part of the TARDIS i had the problem that normally one side would receive no light and that looks really bad. Do you mean that i should increase the intensity of the sun? I will take another look at the scene.