It may not be Google Earth, but Google's latest application for its Android operating system is headed in the direction of at least one Earth's layers--up.
Google Sky Map uses your exact whereabouts, including the direction you're facing and the tilt of your handset, to show you the stars and planets all around. Because the Android phone is an extremely portable device, unlike your desktop or even laptop, Sky Map can heavily lean on the phone's built-in GPS and its accelerometer. This lets you point the phone like a remote to see the sky above. Yet Sky Map isn't bound by such paltry limitations as "up" and "down." With Sky Map activated and the G1 calmly resting by my elbow, I can turn my head to gaze at Australia and the south pole.
Sky Map beams out the location of stars, constellations, planets, and the horizon by default, but you'll be able to change those settings, plus track Messier Objects if you like. Although the screen gets crowded with constellations, labels, names, and numbers, the design team has managed to keep the interface easy to read and control.
With navigating the map equivalent to moving the phone, panning outer space with the track ball or finger isn't supported. Instead, if you're looking for a star in particular, you find it the Google way: by searching.
Pressing "Menu" and then "Search" brings up the search bar, which is prepopulated with planetary suggestions. Instead of Sky Map shifting its face to show you your planet, it produces a blue arrow that induces you to swivel and tilt the phone until you're pointed right at it, and gradually turns to red as you get closer. Compelling you to reorient is a nice acknowledgment of orbit paths. When it comes to search, planets and constellations are your best bet, and we recommend nailing the spelling.
Sky Map for Android may not have a ton of features, especially for those expecting an experience like Google Earth (Windows|Mac), or even Microsoft's Worldwide Telescope. However, it has plenty of cool factor, and its interactive nature has practical application and appeal for urban and hilltop stargazers. Download it free from the Android Market on your phone.