The Orbital Debris and Micrometeoroid Environment – An Overview Presented to: The Sixth DoD Astrometry Forum Presented by: Michael L. Fudge, ITT Industries, Advanced Engineering & Sciences Division December 6, 2000 Washington, DC

Presentation Topics Micrometeoroid and Orbital Debris Environment Population images Catalog composition and spatial density Growth Regulation/Mitigation Measures Summary of US Government policies Other mitigation measures Effect on Growth

Low Earth Orbit Satellite Population Image courtesy of: Nicholas Johnson, NASA JSC

Total Earth Satellite Population Image courtesy of: Nicholas Johnson, NASA JSC

Composition of Satellite Catalog OPERATIONAL SPACECRAFT 7.5% LAUNCH VEHICLE UPPER STAGES 18% MISSION-RELATED DEBRIS 11% FRAGMENTATION 40.5% NON-OPERATIONAL 23% Image courtesy of: Nicholas Johnson, NASA JSC Note increase in Operational S/C %

LEO Spatial Density Orbcomm Tselina 2 Iridium Globalstar/ Strela3 Image courtesy of: Nicholas Johnson, NASA JSC, P. Anz-Meador, Viking Science & Technology

Debris Growth over Time TOTAL FRAGMENTATION DEBRIS SPACECRAFT ROCKET BODIES MISSION-RELATED DEBRIS Image courtesy of: Nicholas Johnson, NASA JSC

Notes on Growth over Time Note “leveling” of rocket bodies operational debris (in general) fragmentation debris Current driver – operational spacecraft LEO constellations – while controlled, “fratricide” (constellation member vs. constellation member) not a threat

Growth Projections Image courtesy of: Nicholas Johnson, NASA JSC

US Government Policies

Other Mitigation Measures/History 1st true mitigation measures in 1980s ELV Industry “self-policing” in US/Europe to mitigate against fragmentations on-orbit: passivation of upper stages Cessation of many operational debris practices; beginning use of bolt-catchers, lanyards, etc. 1995 NASA Guidelines 1998 US DoD Guidelines FAA Passivation requirement 1999-2000 NOAA, FCC getting involved Present Japanese, French, Russian, ESA guidelines implemented 1996-2000