Variation of Area-to-Mass-Ratio of HAMR Space Debris Objects

TL;DR

This paper investigates the variability of the area-to-mass ratio in high area-to-mass ratio space debris objects using multi-year optical observations and a normalized orbit determination method to understand their dynamical behavior.

Contribution

It introduces a normalized orbit determination setup to analyze the variation of area-to-mass ratios in HAMR space debris over time using sparse optical data.

Findings

Area-to-mass ratios are not stable over time.

Orbit determination method is validated with multiple objects.

Optical data over several years reveals dynamical properties of HAMR objects.

Abstract

An unexpected space debris population has been detected in 2004 Schildknecht et al. (2003, 2004) with the unique properties of a very high area-to-mass ratio (HAMR) Schildknecht et al. (2005a). Ever since it has been tried to investigate the dynamical properties of those objects further. The orbits of those objects are heavily perturbed by the effect of direct radiation pressure. Unknown attitude motion complicates orbit prediction. The area-to-mass ratio of the objects seems to be not stable over time. Only sparse optical data is available for those objects in drift orbits. The current work uses optical observations of five HAMR objects, observed over several years and investigates the variation of their area-to-mass ratio and orbital parameters. A normalized orbit determination setup has been established and validated with two low and two of the high ratio objects, to ensure, that comparable orbits over longer time spans are determined even with sparse optical data.