Step 1.
Make a space bakground by adding some noise and using craquelure.

Step 2.
On a new layer, draw a circle. Fill it with white. Run some of those odd shaped brushes around the edges with the opacity turned down to something like 35.

Step 4.
Gaussian blur the shape by like 60. Just make sure you can't tell it used to be a pointed shape. Unhide the fire layer, center the two, and merge them together.

Step 5.
Make yet another layer. Draw a circle hiding most of the white. Fill it with black. Guassian blur it by 4 or so.

Step 6.
Add another layer and fill it all with black. Set that layer's mode to screen. Render a lens flare. Put the lens flare on the edge of the sun. I personaly desaturate the lens layer to make it the same as the sun, white.