Spectral response of Experimental Geodetic Satellite determined from high repetition rate SLR data Original Research Article

The design of the retroreflector array (RRA) of the fast spinning Experimental Geodetic Satellite (Ajisai) allows to determine orientation of its spin axis by means of frequency analysis. Moving spectral analysis (MSA) of the simulated Satellite Laser Ranging (SLR) data gives information about frequencies which can be obtained for the whole range of the incident angle between the laser beam vector and the spin axis of the spacecraft. This frequency signal changes as the incident laser beam crosses consecutive rings of the RRA. Knowledge about spectral response of Ajisai allows successful application of MSA to the Graz 2 kHz SLR data (2003–2011) and determination of 78 spin axis orientation values. The obtained results show that the spin axis of Ajisai is stable around RA 15h22m24.0s, Dec 88.05° (J2000.0 celestial reference frame), and is almost parallel to the spin axis of Earth.