This probably deserves it's own thread, but...ah well.
Another program for planets and hell even galaxies. It's just way too cool. It's free, get it here: http://www.shatters.net/celestia/download.html

And for a crapload of awesome add-ons to make everything waaaay more detailed go here: http://www.celestiamotherlode.net/

Google Earth also has alot more than meets the eye. I'm confused myself since I just got it, I'm not sure how to get the detailed images, even after doing so once.

Time to hit the help forums. These are two programs I'm gonna know everything about, sooner or later.

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