I’ve 2 times the cloud-texture, one time in a renderlayer, because of some strange problems. The most of the setup is just trying to get what I want. The normal thing, I don’t know what is does, but it works :p. The mixing of the background, made in the node-editor, and the turning halo-sphere, are done in the sequencer.
I had a hard time, making it visible, because blender first exported png’s with a alpha of 100% ¬¬… After loading it in in a new blend-file, and using the RGB-channel for alpha, I got the result I wanted. I wanted to do that to do it in the same blend file… but Blender doesn’t support sending the images form sequencer to the node-editor.