Thanks, I'll give it a try.
Well, so I cheated.
I'm a newbie tho. Radial gradient on the Nasa coronal mass ejection loop pic, blended onto a casserole or pizza dish we had some time ago. I ended up using a soft edge brush inside and around the loops, and blurring also the right side photo "line" edge of the nasa photo . . . the bottom edge is in the edge of the glass so it blends right in, you can still see the left edge at least a bit.
Not sure what else to have done, though, but at least you can see my sense of humor here . . . ! Most of the links to previous homeworks in this thread were busted, so I could see very few of people's work.