Automatic True North detection during absolute magnetic declination measurement

Abstract

Abstract. Absolute magnetic measurements are of great importance in magnetic observatories. They allow not only instrument calibration but also data quality checking. They require the Vertical and the geographic North as reference directions, usually determined by means of a level and by pointing an azimuth mark respectively. We present here a novel system able to measure the direction of the magnetic field, of the Vertical and True-North. A design of a North-seeker is proposed taking into account sensor bias as well as misalignment errors. Different methods are derived from this model and measurement results are presented. A measurement test at high latitude is also shown.