In the Jewish Midrash, Satan is merely an angel, sent to earth by god, to tempt men and test their faith - it was Christianity that made him a monster, a fallen angel, and the President and CEO of Hell.
We always see things like this and say that looks like... But to me if something should look like something, then it goes to show that it should look like that also from another angle. A cloud that looks like a pig from where you are, might look like a hand giving you the finger if you were somewhere else. If it really is a cosmic hand, then it should look like a hand from a different angle. Unfortunately, we can't look at it from a different angle, because the distance is far too great. But it's safe to assume that it does look nothing like a hand, say from ninety degrees from our position, using the hand itself as the axis.