Shape and Motion Estimate of LEO Debris Using Light Curves

Abstract

We succeeded in determining a tri-axial ellipsoidal model of one LEO debris Cosmos 2082 rocket body, its rotational axis direction in the celestial sphere, a compositional parameter, its rotation period and its precession using only light curve data that was obtained by an optical telescope. The brightness of the LEO debris was monitored for 2 days. The method of the least squares fitting is applied to determine these values. The derived axial ratios of the LEO debris is 100:18:18, the coordinates of the rotational axis direction in the celestial sphere are R.A. = 305.8^º and Dec. = 2.6^º and its rotation period is 41 seconds. When the precession is considered, its amplitude and precession period are 30.5^º and 29.4 minutes, respectively. These results show that optical light curve data are sufficient to determine the shape and the motion of LEO debris.