Debris model validation and interpretation of debris measurements using ESA's proof tool

During the last years a number of observation campaigns to monitor the Eart h's space debris environment using radar and optical sensors have been perf ormed. In addition, space debris models like the ESA MASTER Model have been developed based on the simulation of debris generating events. To validate the models using the results of a measurement campaign, a filter has to be applied to transform the object data into detection rates considering the observation scenario and the instrument parameters. PROOF (Program for Rada r and Optical Observation Forecasting, developed under ESA-ESOC contract) i s such a filter and thus a link between models and measurements, This paper addresses validation aspects of the MASTER-99 debris population using the PROOF tool. Besides, emphasis is given to the method of PROOF and on the de monstration of the consistency of its results. It is shown in this context that the sensitivity of the modelled instruments matches measured threshold s for both instrument types (telescope and radar). For the validation of th e MASTER-99 model, PROOF has been applied for the simulation of the latest TIRA and Haystack beam-park experiments. The comparison shows that the mode lling of the space debris environment shows some deficiencies in the 80 deg rees inclination band and at altitudes of 900-1000km. For the GEO region, d ata from the ESA Space Debris Telescope have been used. The PROOF results r eveal a lack of decimetre sized GEO objects in the MASTER model. (C) 2001 I nternational Astronautical Federation. Published by Elsevier Science Ltd.