I realized just last night that when I comb my hair and let it fall into it's natural position, I have Carl Sagan's exact hair! (My girlfriend just looked at me in disdain all like "Fuck you! You're no Carl Sagan!" But she wasn't there, so she doesn't fathom the actual similarities.)
Thanks! It was all done in photoshop, using a number of different photographs of Carl Sagan as reference for the drawing (was tricky to get his smile just right), and a very hi-res hubble photograph (which you can download at [link] most of the images there count as being in the public domain) for the galaxy in the background!