Over the next decade plans have been advanced for 100,000 new satellites in Low Earth Orbit (LEO, altitude less than 2000 km). This will increase the total number of objects in this orbital regime by at least a factor of 5, including active satellites and debris larger than 10 cm. I'll review why these constellations of satellites are planned, why so many are needed, and what the basic design parameters of a satellite constellation are. The first of these constellations have been launched: SpaceX Starlink satellites and OneWeb satellites. For the appearance of the night sky to the unaided eye and ground and space based optical astronomy, the night sky will never be the same. These new satellites could be brighter than most of the objects in orbit today, producing contamination by satellite streaks in astronomical images. The growing spatial density of objects in LEO leads to an increased risk of collision between objects in LEO and the increase in the space debris population.
23/09/2020
BIO
Patrick Seitzer is a Research Professor (Emeritus) in the Dept of Astronomy of the University of Michigan in Ann Arbor, Michigan. His research interest is optical observations of satellites and space debris, primarily at geosynchronous orbit. This involves surveys for finding objects and then characterizing them using photometry and spectroscopy from both ground-based and space telescopes. He held staff positions at Cerro Tololo Inter-American Observatory in Chile, the Kitt Peak National Observatory in Arizona, and the Space Telescope Science Institute before coming to Michigan.