AJISAI Spin Parameters Determination using Graz kHz Satellite Laser Ranging Data

We determined the spin rate and direction of the spherical satellite AJISAI as well as its slow down between 2003/10 and 2005/06 using Graz full rate kHz satellite laser ranging data. The high density of the kHz data results in a precise scanning of the satellite's retro-reflector panel orientation during the spin motion. Applying spectral analysis methods, the resulting frequencies allow to identify the arrangement of the involved laser retro reflector panels at any instant in time during the pass. Using this method, we calculated the spin rate with a high accuracy (RMS of 0.000403 Hz), and the slow down of the spin rate during the investigated period with a magnitude of 0.0077497 Hz / year. We obtained these results in near real time from automatically performed analysis procedures during routine SLR tracking, i.e. day and night observation, without any additional hardware.