What we need to do now is get rid of the atmosphere that's on the dark side of the part of the planet, because there is no visible atmosphere on dark sides of celestial bodies.
Select the eraser tool and pick a big fuzzy brush. Set the opacity to 75% and flow to 100% and start erasing smoothly until you have a soft, smooth-looking atmosphere. Mine looks like this
Now we have the base file for a planet. You can apply any texture that you want to this, so go right ahead and save it as a PSD to preserve layer configurations.
Texturing the Planet.
At this moment, you should have 2 documents open in Photoshop:
- Texture file
- Base planet file
In the texture file, you should have your texture selected. Go ahead and bring it into the base planet file, and place the layer between the base and the atmosphere layer. Of course, our texture is 4 times bigger than our planet, so you will resize it to fit the planet (remember to hold down the shift key in order to keep the proportions). If you aren't very good at resizing and end up with a texture that is slightly bigger than the planet, ctrl+click (or apple+click) the base layer, invert it (ctrl+shift+I for pc, apple+shift+I for macs) and then hit the delete key or the backspace key.
Take the texture layer, rename it to "land" and set it to screen. That should look something like this.
NOTE: If you need an "accessory" planet, which is a happen that happens to be far away from the viewer and lots of detail is unnecessary, you can use this. However, we will use a lot of detail for really nice close-ups.
What we will do now is have a nice uniform land texture that won't get in the way with our clouds. So what we do is set the land layer to 33% opacity, duplicate it, rotate it 90 degrees clock-wise, duplicate it again, and flip it again in the same direction. Then link all of the 3 layers together and merge them. Now go ahead and set this layer to Overlay or Soft Light (the choice is up to you). My texture looks like so.
Note: if you wish to use this as your final planet, you might want to do some brightness/contrast adjustments to make it look sharper and more realistic:
I use -50 for brightness, +50 for contrast, and then desaturated it a bit (-50 in hue/saturation controls.