- GPS and system hour will help you to stablish the location parameters.
- Compass and accelerometer of the device will indicate you the position of the comet.
- Camera will allow you to precisely align the virtual comet with the real one.
* The efficiency of the process strongly depends on the device sensors precission. Please, use any compass calibration app (f.e. gps essentials).
The comets parameters are obtained from the website of NASA (JPL) . Hyperbolic equations for the comet trajectory have been used with some minor approximations.
Average error lower than 1'', compared with data from heavens-above http://www.heavens-above.com/comet.aspx
The focal length of the camera (width and height angles) has been used to place objects in the screen. If the compass and accelerometers of the device are accurate, this app is also accurate enough.