Here's a great Android app for all of you space nerds out there: Google Sky Map. Just like Google Maps and Google Goggles help you discover what's around you, Google Sky Map for Android phones shows you what's happening in the night sky. The app uses the phone's orientation sensors to pinpoint your location and map out the night sky as you see it. You can explore planets, constellations, and stars by pointing your phone to different parts of the sky — the display will move with your hand providing info about what you're pointing the phone at. Or, if you're looking for a specific star or planet, use the app to search, and Sky Map will direct you to the point in the sky you're looking for.
To download, search for "Sky Map" in the Android Market, or download from Google's site. And if you want to keep exploring from the galaxy, don't forget about Google Earth's Sky Feature.