I like the idea. It's a vary cute composition

The shadows on the dog and the "bone" don't mach. And using refine selection and Decontaminate color is a good idea for removing that green fur on the kitty. And you can tweak the exposure a bit so all the segments mach. A soft color overlay might do the job.

Thanks Nichev for taking the time to make some helpful advice. I worked on the changes you suggested, I think it made the work better.

I like what you've done, author! Really love the lights and color too.

Not bad, but the star field looks phony.

Thank you!
And also I will make improvement on stars. Thank you for suggestion!

Good luck author! You should find this tutorial helpful, although there are plenty of usable star field pics out there.
http://gallery.artofgregmartin.com/tuts_arts/making_a_star_field.html

Wow, this is awesome! I'll working and practicing on this Thank you very much!

Hawks are much larger, and the red flesh tones of the hand sources could be toned down, but it's a good effort.

Thanks CMKY. I had not noticed how red the hand is, you are right. About the size of the hawk, though, all the doghawks I have ever seen have been quite small.

LOL @ Doghawks...okay author, you win that one.

This is a good study in proportioning. I'm kind liking it.

The light source is from the right, so the Earth should be flipped accordingly.

I know the Earth looks way too big and the craters way too small but it was not meant to be realistic. More of a, Dog in a space suit standing in front of a wallpaper, thing. But as CMYK46 mentioned, I messed up the lighting and positioning a bit

Thank you for the comments! I'll try and fix it ASAP

if we can see the curvature of the moon then we should see the same shadow on the earth (easy fix)
good luck