Pretty. Though the shadows are not all correctly aligned on all of the moons visible in the picture.
...aand, a nova in the same system would be pretty damn much brighter, but let's just say it's a smaller eruption/explosion on the surface of the star, that could very well cause a gas burst around a star much similar to what is seen here.
Do you have it on bigger resolution or did you work it on that size? I would suggest working on bigger size, then saving it in uncompressed form and putting a high-quality JPG file to net... That's what I do. If you got it on bigger size, I'd like to see that also.
How did you make the rings of that planet? They are IMO the best single thing in this pic.