Systems Engineering Seminar

Orbital Debris Mitigation – Safe Disposal Planning Begins at Concept Design

Presented by:
Scott Hull /591 and Josephine San /591

October 7, 2003, 1:00 p.m.
Building 3 Auditorium

Abstract:
Orbital Debris Mitigation - Safe Disposal Planning Begins at Concept Design

Orbital debris issues have received renewed interest in recent years, both in terms of the on-orbit debris environment and risk to the world population during reentry. NASA policy requires that spacecraft designs allow for limiting their impact both during and after the mission. Designing for safe disposal at the end of a mission is an iterative process of reentry survivability analysis and design modifications, resulting in the selection of an appropriate disposal method.

This seminar focuses on the factors involved in the selection of a disposal method and the planning needed to successfully achieve disposal. The importance of reentry survivability software will be discussed, as well as various approaches to envisioning spacecraft breakup and burnup. Examples of Design for Demise techniques will also be presented for limiting the surviving debris, and thus the risk to the population. Safe Disposal Planning from concept design through the end of the mission implementation will be discussed for several different disposal methods including controlled reentry, uncontrolled reentry, and altering the orbit to achieve a long-term storage orbit. In addition to NASA policies and standards, GSFC procedures, guidelines, and work instructions will be presented.

Biographies:

Scott Hull is an Orbital Debris Engineer in the Guidance, Navigation, and Control Systems Engineering Branch, Code 591. He has three years experience with simulating spacecraft breakup and burnup, and has performed reentry survivability simulations on numerous spacecraft using both DAS and ORSAT software tools. He has worked at GSFC for 13 years, in failure analysis, electronic parts engineering, space science mission operations, and orbital debris control. Current activities include Design for Demise, early mission design for limiting debris generation, and a cooperative effort with the Aerospace Corporation to produce a reentry breakup data recorder. Mr. Hull holds a Bachelor's degree in Materials Engineering from Drexel University.

Josephine San has been working at GSFC for over 16 years in the Guidance, Navigation and Control Area. Her first assignment was to develop, integrate, and test the control flight software for a Two Axis Pointing System for BBXRT. In the next ten years, She developed the attitude determination and control algorithms for SAMPEX, XTE and TRMM, performed control system analysis for numerous spacecraft and launch vehicle, and became the lead engineer for LASERCOM, and TOMS-EP. Then, she concentrated her career in the spacecraft concept design for a numerous projects and for the Integrated Mission Design Center. About two years ago, she began her adventure in the orbital debris mitigation area. Currently, she is the TRMM Reentry Operations Lead Engineer, Orbital Debris Lead Analysis for SDO, ACS Lead Engineer for MMS, and the author of two PGs - GSFC Orbital Debris Mitigation PG and End-of-Mission Planning PG.