Nathan Estell, University of Michigan, Department of Aerospace Engineering; Dylan Ma, University of Michigan, Department of Aerospace Engineering; Patrick Seitzer, University of Michigan, Dept of Astronomy
Keywords: Daytime Imaging, SSA, Optical
Abstract:
Daylight imaging of satellites in Low Earth Orbit (LEO) affords several unique advantages not present in traditional nighttime imaging. For many satellites, there are more passes over a ground observation site in daytime than twilight passes, when the observer must be in darkness and the object in sunlight. During most night time passes the satellite is in Earth’s shadow and thus invisible to optical detection by reflected sunlight. With more frequent observations, more accurate orbital elements can be obtained and uncertainty reduced. There are many challenges to this type of observation, however. Principally, atmospheric scattering produces a background sky many orders of magnitude brighter than at night, greatly reducing SNR and limiting observations to the brightest and largest satellites. Additionally, the astrometric value of observations is reduced for lack of background reference stars.
This project investigates using a commercially available, small-aperture optical system to image satellites in daylight with a CMOS camera. The project demonstrates the custom tracking program, including sun avoidance. Several satellites in LEO were imaged in daylight and tracked for the duration of the pass. We hope this project will prove that low cost optical observations of LEO objects in daylight is feasible, opening the door to widespread usage of this method in SSA.
Date of Conference: September 17-20, 2019
Track: Optical Systems & Instrumentation