Step 1:

Creat a new (500x500px) image.

Step 2:

Select the brush tool and select a decent size. Go to the brushes palette and add a texture. I'm using a rocky texture, but it won't make a difference. Make sure the blending mode is set to 'Multiply.'

Now brush all over your canvas.
Once you cover all your canvas, change the brush's texture to something different, then brush it over the canvas again. Do this a third time if you wish. You should have something similiar to this:

Step 3:

Now your done with that, create a new 500x500px canvas (or the same size as the last one).

Step 4:

Make sure you have the defualt black and white colors selected. Then on the background layer, hit alt+backspace to fill it with black.
Now create a new layer and use the elliptical marquee tool while holding shift to click and drag a perfect circle. Leave about 40px on the edge for the atmosphere of the planet.
Hit alt+backspace to fill this selection with whatever color you want (I used magenta).

Step 5:
Select the texture image you made in steps 1-2. Press 'V' or select the move tool to click and drag it onto the new image you made in step 3. Make sure it's covering the whole canvas.

Step 6:
This is a little bit tricky if your a newbie, it's hard to explain so i'll try my best. With layer 2 (the texture layer) selected, hold ctrl then click on layer 1's THUMBNAIL (the little image next to its name) this will create an elliptical selection.
Hit ctrl+shift+i then hit delete. Now hit ctrl+shift+i again. Don't deselect it yet.

Step 7:
Now go to filters>distort>spherize. Then use the defualt. Now hit ok, the ctrl+d to deselect the image.

Step 8:
Now Move layer 2 BELOW layer 1. Now we are going to make our atmosphere.
On Layer 1 double click it and apply these settings (make the glows whatever color you want your planet to be):

Step 9:
Now on LAYER 2 (the texture layer) go to image>adjustments>hue/saturation.
In the bottom right of the dialog box is a check box that says 'colorize.' Make sure it is checked.
Now mess around with the settings until you get a color you like. Like this:

Step 10:
Now you could be done with it and call this a planet. But it would look more realistic if you added a shadow to it. So create a NEW layer. Then use a black to transparent gradient. And click and drag it to where you want your light to come from. Then hit 'ctrl+t', right click, then select 'warp'.

Step 11:
Move the gradient around a little and presto! Your done!

I hope you learned something from this tutorial and incorperate it into your own ideas!

Wow, great tutorial! Thanks a lot. I'm definitely going to try this one soon. And of course welcome to CrystalXP!

Thanks, glad you like it  

I think I am going to have to try this one this evening.  Looks interesting  Will post results

Good tutorial, though I think it could have been written a little simpler.  Not a problem though

I am a total noob to all this but I wanted to have a go, thank you for having something for begginers.

It took me a litle while but I learned a lot of it! Here's my result

 Tnx a lot! I finally got it now! before i don't know how to do the shadow.
   

The only thing that bothhiners me is the shadow thingy. I got confused.

Are you using photoshop cs? or cs 2?

Hey, nice tutorial, i had a try at it here are my results    

Hahh! I did it!
It's awsome! I love this tuto  Here is my first result : the Planet Hell

I've made a whole picture based on this tuto and want you to  tell me your  opinion

It's better in full size

Pretty cool result you have there. I think that the 'glow' around the planets looks a bit weird in your image though. It's a bit too visible and isn't very realistic.

Yeah, Gruzz have a right. Try to decrease Spread and Size of Outer Glow And I think that mountains behind city are too much blured  

I like the city dome and reflections

BTW below is my planet. I've made it couple months ago, not with that tutorial, byt by myself

Great tutorial!!  

i know.. but couldn't do anything special for the mountains...

you're right.. i'll correct the planets...

Can someone tell me how to create Textures? cuz i don't have so much presets, and the blue planet is a piece os s**t i think....

I've take my textures from Celestia3D program (virtual space). There is a lot of hi res textures Just look here
Link 1
or here
Link 2

cool thanks! useful site

No problem bro

Great work man!!!

awsm tut man...am kinda new here..but u all rock...thx a milln

That kind of speaking is not really allowed.  There are too many people that need to use online translators to read the posts.  SMS style language does not translate.

I don't really get this step. Can anyone tell it to me in a simple easier way?

I'll try to. Usually step by step approach works best, so here we go.

- Select layer 2, it will now turn blue on the layer window.
- While holding Ctrl, click on the thumbnail of layer 1. This will make the area of layer 1 selected. Make sure that layer 2 is still blue, this is the layer you are actually going to work on!
- Use Ctrl + Shift + I to inverse your selection. Now hit the delete key. This will delete a part of layer 2 if you did it correctly.
- Use Ctrl + Shift + I again to inverse your selection back. Don't deselect it and continue with the rest of the tutorial.

Thanks. so simple. But, when I drag the texture layer on to the "circle" layer, and position it, it moves my elliptical shape I made