This tutorial is fairly complex and relies on the presumption that you are familiar with many of the blending modes and tools of photoshop already. However, it also is optimised for maximum potential of experimentation, so that you may learn from the tutorial rather than following it to the letter. PLEASE try and learn something from this, for this is why i make these tutorials available.

I hope you find this useful.

On a black background make a new layer. Using the circular marquee tool and holding down shift draw a circle out, then fill with a colour of your choice, i chose white, purely for convenience. Call this white layer, circle.

Now on a new layer, find a planet texture you like to use and paste it down. Select the circle layer by holding down ctrl and clicking on the layer circle. Invert selection by going to select -> inverse. Now delete the texture outside the circle.

Select the circular texture layer and spherize to 100% twice. Label your texture layer, planet texture.

Now try different methods to heat up the surface. Try duplicating the texture and setting to overlay. Do that again and then duplicate and set to multiply. Repeat that final step, that gave me a fairly good result. That gets us the boiled skin of the planet.

Selecting the best texture next is a key part to this tutorial. It must have lots of cracks for a start, and it helps if they are dark or black cracks. I chose the texture on the left for this particular instance.

Now what you do is to paste your texture over your planet, and call the new layer cracktexture. The closer the texture is to the size of the planet the better, so if the canvas is 1000*1000 and your planet is 900*900, then a texture that fits exactly on the canvas of 1000*1000 is perfect.

Now since your textures cracks are black, and an exploding planet has white hot magma etc, you'll need to change the colors a little. So selecting your cracktexture layer hit ctrl+i to inverse the colors, thus achieving the desired effect. Then set the crack texture layer to hard light. Desaturate it also, we'll bring up the colors next.

Now to make this texture fit the planet. Ctrl+click your circle layer to select the circle shape, go to select -> inverse and delete the crack texture outside the planet. Like earlier, spherize to 100% twice. Instant fit huh.

Except the colors are a little off and not exxaggerated enough, so we'll solve that by duplicating our cracktexture layer twice, setting the middle layer to multiply and the top layer to vivid light (you need photoshop7 im afraid). This should accentuate all previous effects and make it look like the image on the left, dead sexy.

Now the colors need fixing now, make it look like it's melting down and about to explode. So selecting your original cracktexture layer (the hardlight one), hit ctrl+u and use the following values.

Colorize = check
hue = 35
saturation = 50
lighting = -20

Select the multiply cracktexture layer, and use

Hue = 20
Saturation = 25
Lighting = -35

Now i'd leave the top one alone as not to disturb effect anymore, and as vivid light is a delicate layer mode.

This part is the tedious bit. Create a new layer above all else an label Rays. Grab your magic wand tool, and choose the nearest crack texture layer. Click on a white part of layer (the crack part), now switch to the rays layer and fill this selection with white. Repeat the process for as much of the white cracks as you can, so you end up effectively painting over the initial cracks, and achieve something similar to the image on the left.

This is pretty much the end part, make sure nothing is selected. Choose your rays layer and run a radial blur zoom filter on it with your own settings, make the white rays come out. To enhance these, duplicate the rays layer, set to overlay. Then use the ctrl+u settings of

Hue = 35
Saturation = 25
Lighting = -50

Duplicate this overlay layer and set to color burn. This will accentuate colors.

Try adding textures to the rays, brushing around the cracks and light to add atmosphere, debris etc. Try different layer modes and styles, go wild, this is all experimentation.