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       Departments of Mathematical Sciences and Biostatistics
                    The Johns Hopkins University
                                                                       
                           JOINT SEMINAR

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Professor David R. Brillinger          February 17, 2000
Department of Statistics               Room W2017
University of California at Berkeley   School of Hygiene & Public Health
                                       Refreshments: 3:30 p.m.
                                       Seminar: 4:00 p.m.

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      SOME STATISTICAL ASPECTS OF SPACE DEBRIS RISK ASSESSMENT
                                                                        
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                             ABSTRACT

There is now a very substantial amount of space debris circulating the
earth and posing a risk to satellites, space stations, and space craft.
The larger pieces are tracked individually; however the smaller (less than
10 cm.) seem better viewed as a population and sampled.  The sampling takes
place by radar, and estimates of various characteristics of the objects
passing through the beam may be inferred from the return signals.  A variety
of interesting problems involving time series and marked point processes
arise and will be discussed.

Here is a definition of space debris risk assessment: the estimation of the
probability that certain performance variates of a space object of interest
exceed relevant critical levels, within a specified time period, as a
result of collisions with space debris.

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