Create a planet in Photoshop

Preparation

There's not much to do to prepare for the planet's creation. All we need is a new document with some background. I've used a 1280x800 document with a space background, created in this tutorial. But it's basically just visual eye candy so you don't need to create it yourself if you're not interested. You can just download the picture below or use any other picture (or even a black background) if you like. Here's the picture i used to see how my planet would look like in a space scene:

Next thing to do is to get some terrain for your planet. You can download it from internet. I've downloaded my texture from here. The planet

Copy and paste the texture on a new layer and with an elliptical marquee tool

from the tools palette draw a circle. To ensure that you're drawing a circle, hold SHIFT while drawing. Make sure you have the texture layer selected and press CTRL+J. This will take whatever is in your selection and transfer to a new layer. Delete the texture layer and position your planet layer whereever you want.

What i've done next is duplicated the planet's layer, moved the duplicate below the original and disabled it like this:

The only thing i've done this for is so that i could easily select the planet in the future. To select it, i just have to CTRL+CLICK on the hidden layer's thumbnail. I might add something to the planet that would change its shape a little and selecting the planet itself would not give me the same circle. You can also save a selection instead of using my method by pressing Select > Save Selection ... and load it whenever you need it. I prefer my method, because ... because i just prefer it :) OK so the next thing we're going to do is make a sphere of this flat circle that we have now. To do that, load the planet's selection by CTRL clicking on the hidden selection layer's thumbnail. Now go to Filter > Distort > Spherize .... Use these settings:

Now our planet starts to look like it's an actual sphere. But it's still flat. Let's fix that by adding some depth. Create another copy of planet's layer by pressing CTRL+J (press CTRL+D to deselect everything first). Name this layer highlights. Go to Filter > Stylize > Emboss ... and use these settings:

Duplicate highlights layer and name the duplicate shadows. Select the shadows layer and press CTRL+L to bring up levels adjustments. Drag the right slider to the left until your planet starts becomes white with some dark shadows like this:

Now hide the shadows layer by pressing an eye next to it and select the highlights. Press CTRL+L and this time drag the left slider to the right until you get something like that:

Enable the shadows again. Set the shadows blending mode to multiply and linear dodge mode for highlights. The result should have some depth now:

As you will probably notice, there's too much depth. If that's the case, lower the opacity of both highlights and shadows layers. In my case i also have some unwanted artifacts on the left side of the planet so i had to erase them from shadow/highlight layers. Select the planet layer with both highlights and shadows and press CTRL+E to merge them. Next thing to do is add some atmosphere. We'll do it with layer styles. Create a new layer on top of everything and load the planet's selection (still remember how to do that? :). Set the foreground color to black and press ALT+BACKSPACE to fill it. Change the new layer's fill to 0. This will hide the contents of the layer, but the layer styles will still be visible. Here's what layers we have so far:

Rename the topmost layer to blue glow and double-click it to open layer styles. Add the following layer styles:

The color, that was used for the shadows, was #847eff, but you should pick the one you like the most :) Also if you used different image and planet proportions than i did, you'll need to play with these layer styles until you get a decent looking result. Now duplicate this layer by pressing CTRL+J and name it white glow. Double-click it and change the styles to these:

And here's how our planet looks now:

Create a new layer on top and name it shadow. Load the planet's selection and fill it with black (ALT+BACKSPACE). Go to Filter > Blur > Gaussian Blur .... Again, if you used similar proportions as i did, apply a ~12px blur. After that, position the shadow layer as shown below:

Now select the planet's layer and both glow layers and press CTRL+E to merge them. Select the shadow layer and go to Layer > Create Clipping Mask. Change its opacity to ~95% and press CTRL+E to merge it with the planet. And there you have it: a planet in Photoshop:

Here's what i've managed to come up with: