Design and construction of a high resolution, portable and low-cost positioner by a star tracking system

In normal observation procedures, the position of the observer is specified by GPS and celestial positions of an object will be calculated. But in some situations, like small zenith angle FOVs, GPS doesn't work. Therefore in this study, the work is investigated in reverse of usual procedures. Comparison between the local position of a few stars in a typical picture and their reference positions in J2000 is used for determining our location coordinates. Longitude, Latitude and North direction are determined by the procedure. The stars are identified using their unique patterns with neighbor stars. The direction of the sky photography is determined by a designed inclinometer which is harmonious to a camera. For the purpose, it was corrected atmospheric refraction effect, relativistic aberration. It was used half seconds exposure time images to obtain the best results. Therefore this positioning system is used to obtain longitude and latitude with an accuracy of less than 0.503 and 0.816 arc-minutes respectively. Total weight of the system is 4.7 kg, which makes it quite portable.