Physics and Astronomy
Dugan, Owen (School: Dugan Homeschool)
SpaceX’s Starlink satellite network promises world-wide high-speed internet access. With up to 42,000 satellites to be deployed, however, the Starlink satellite network will significantly degrade ground-based astronomical research and imaging due to trails (e.g., light reflections or emissions) from passing satellites. Removing the effects of satellite trails on night sky images is recognized as difficult because accurately identifying satellite trails is challenging and satellite trails effect not only the brightness measurements of stars they pass in front of but also the brightness measurements of stars in the vicinity of the satellite trails. Novel algorithms were developed and coded to accurately identify and remove satellite trails and reduce their effects on photometry. Platesolving is used to identify stars within an image, and an algorithm is employed to determine the radius of each star identified. Identified star brightnesses are replaced with median image brightness values. Satellite trails are identified by examining each possible line traversing the image, with recursive sizing using area interpolation implemented for large images to reduce processing time. Area and/or cubic interpolation is employed to optimize satellite trail modeling to within a tenth of a pixel. A Gaussian brightness profile is developed for the satellite trail to account for satellite trail effects across the entire image. The code returns original star brightnesses to the image and the satellite trail is removed by applying the additive inverse of the fitted Gaussian to every pixel in the image. Significant reductions in the effects of satellite trails on images captured using Earth-based equipment are observed while improving image photometric accuracy.