Where is Io – Astronomy in your pocket¶ ↑

Description¶ ↑

Where is Io is an Android application that calculates many of the ephemeris (positions of the planets / moons) for the Solar System. It originally focussed on the moons of Jupiter, but since has branched out to support rise and set for the planets, and more is coming.

For the moons of Jupiter it numerically calculates the positions of all the moons as well the Earth and Jupiter, does the projection from Earth’s perspective, and pulls it all together in a familiar spiral graph.

This is available in the Android Market if you search for “Where is Io”.

More information on the project can be found at dague.net/where-is-io

Building¶ ↑

The source tree is an eclipse project, and should be buildable in eclipse with the following caveat:

For my convenience I added an ndk builder for the .c code. The ndk build environment doesn’t mix super cleanly with eclipse, so if you want to build this yourself you’ll need to mess with .externalToolBuilders/JNI Builder.launch

Authors¶ ↑

Sean Dague - maintainer

Additional Contributors:

* Keith McGerald
* Martin Staehling

License¶ ↑

The code for the code Android application is under GPLv3.

The application also includes the work of Johannes Gajdosik as found in the Stellarium source tree. Those files are provided under the revised BSD license that they are licensed under. I did a jni wrapper on this code for the application.