Unfortunately, I hadn't quite got the planet thing down yet, so it has a strange glow (drop-shadow!) about it, which even has aspect problems with the original planet. And yes, you can see stars through the planet - it really is translucent. It has virtually no atmosphere either.
This was my first time making a comet. It took me a while to figure out how to do that properly - it's a supernova on a black background with several white/black symmetric conical gradients overlayed on top of it. It's still rather tricky to tone down the front a bit, and I have to be careful not to cut off the comets, as I did in Stairscape.