DENSITY AND MASS DISTRIBUTIONS OF ORBITAL DEBRIS

Area-to-mass ratios for orbital debris tracked by the U.S. Space Comma nd were calculated from observed changes in apogee and perigee altitud e due to atmospheric drag. The area-to-masses observed for the orbital debris were similar to those found for debris from laboratory breakup s, and suggest that much of the debris is composed of crumpled thin pl ates or of insulation material with low effective density. Areas for t he debris objects were derived from radar cross-section data. Object m asses were calculated from the ratio of the RCS-derived area to the ar ea-to-mass ratio. Analysis of the distributions of fragment masses fro m the breakups suggests that in many cases, only a portion of the init ial object breaks up into small fragments. Copyright (C) 1997 Publishe d by Elsevier Science Ltd.