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. = 305.8o and Dec. = 2.6o and its rotation period is 41 seconds. When the precession is considered, its amplitude and precession period are 30.5o 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.