Sky Map for Android - A Mobile Planetarium

I originally heard about Android on my first day at Google. A colleague and I were excited about all of the features that would be present in the platform, such as the GPS, compass, and motion sensors. As astronomy buffs, we talked about how cool it would be to use these features in a mobile application that would correctly display the sky based on your location and the direction you're facing.

Fast forward 12 months. We produced a "prototype" of the mapping application consisting of a phone, a compass, a level, and a map, and then convinced several others to join the project. Now that there was some excitement around the project, the real development could begin.

We were able to play around with a T-Mobile G1 test device in the office and were intrigued by all of the sensors that were available. The GPS and clock allowed us to generate maps for the exact time and location, but the compass and accelerometer were what made Sky Map truly interesting. Using these two sensors, the app can determine the exact direction that your phone is facing and display the stars that are visible. If you want to identify that bright star in the west, all you have to do is point the device in that direction and you'll see "Venus" appear on your screen.

Because we do work for Google, it was perfectly natural for us to add a search feature. We decided to use the location features in the Android platform to implement search in an easy-to-use way. You enter the name of an object of interest, like Saturn, and the phone displays an arrow pointing to the object. As you get closer, the color of the arrow goes from blue to red and the app circles the object when you find it. Voila!

This month is a great opportunity to do some planetary observing -- spot the elusive Mercury in the evening, see Jupiter and Neptune in same binocular field, or view Venus shining in the morning skies. Sky Map was designed to help you navigate the night sky, making months like this particularly exciting! Since 2009 is the International Year of Astronomy, there will be plenty of opportunity to show off the application to your friends.

Download Sky Map from the Android Market, and let us know what you think. We'd love to hear from you, both the good and the bad. You can leave comments here or in the Help Forum.

Update: We have updated the version of Sky Map for Android in Android Market. We realize that some users were experiencing crashes or slow start-up times. This new version fixes these issues, so Sky Map should now work fine on all Android-powered phones. (May 13, 2009 10:10 pm PDT)

Posted by Kevin Serafini, Orbiting Software Engineer