Space-based visible space object photometry: Initial results

One of the objectives of the Midcourse Space Experiment surveillance experi ments is to collect photometric and radiometric data on a selected set of r esident space objects from the long-wavelength infrared through the short w avelength ultraviolet region of the spectrum. This was done using the Spati al Infrared Imaging Telescope III, Space-Based Visible (SBV), ultraviolet a nd visible imager, and spectrographic imager instrument packages onboard th e spacecraft. Analysis of these data will primarily emphasize 1) constructi on and validation of phenomenological models for a broad range of resident space object classes, for example, spin- and three-axis stabilized satellit es, rocket bodies, and orbital debris, over a wide range of solar phase ang les and 2) discrimination between classes of resident space objects and ide ntification of discriminating characteristics within a resident space objec t class. We concentrate on the initial results from the SBV instrument. We provide an overview of the surveillance data collected to date, discuss its limitations, and present examples of the data collected on tao classes of resident space objects.