More than 2,500 active satellites now orbit the Earth, and amateur astronomers and other observers are seeing more every month.1 Historically, satellite communication involved geosynchronous (GEO) spacecraft—large systems that have become increasingly capable over the years. But now nongeosynchronous-orbit (NGSO) communications constellations, including low-Earth-orbit (LEO) and medium-Earth-orbit (MEO) satellites, are taking to the skies, and their number could soon soar. If current satellite internet proposals become reality, about 50,000 active satellites will orbit overhead within ten years. Even if the most ambitious plans do not come to pass, the satellites will be manufactured and launched on an unprecedented scale.