This project is about a star pointer which allows you to see the sky with the stars and constellations. The star pointer was an embedded board PIC, connected to a computer with RS-232. Then, we developed a simulator on Android operating system. The computer received the orientation information of the PIC board or the simulator. With those, we could compute the celeste map and then display it. You could see the stars, constellation, the moon (with its different waxes and wanes) and the sun. More information about stars or constellations were available just by clicking on their images. We also created a search engine to find the stars and constellations.
Sky visualisation with basic projection
The sky is actually a complete sphere from which we can only see a little part at a given time. To represent that sphere on a flat computer screen, it is necessary to project coordinates from spherical representation to planar representation. Lots of technics exist in order to accomplish that, but only the simplest one was used on this project. Spherical coordinates are simply taken as polar coordinates on a mathematic XY plan, which is then displayed with a zoom factor on the rectangular screen. Movements then consist of rotating around the central point, moving up or down and zooming to see more stars.
Configure settings to access PIC controller settings and use queries for accessing large database
To communicate with the PIC controller, a various number of parameters need to be specified. In order to be quite flexible and use different type of "star pointer", you can choose values to the different settings. Star2 contains more than 120'000 stars visible with a telescope from Earth ground. To facilitate which stars the user want to display, he can use queries to filter the desired stars.
Mathematic operations all over the application
Mathematics are present in almost every part of the project. Projection of sky from a sphere to a plan uses mathematics. Computation of star coordinates from generic static ones to current sky specific ones uses mathematics. Gathering altitude and azimuth angles from X, Y and Z vectors coming from hardware accelerometers embedded on star pointer uses mathematics. Computing universal time based on local time and abstract epoch notion uses mathematics. All the needed formulas were discovered by ourselves during the development process. With all of this, you can compute the necessary information if you want to point a specific star !