Astronomer tracks decaying Starlink orbits to measure atmospheric density

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An astronomer is monitoring the gradual orbital decay of Starlink satellites as a method to study Earth's upper atmosphere. As satellites sink lower over time due to atmospheric drag, their rate of descent provides data on atmospheric density at high altitudes. This approach effectively turns the large Starlink constellation into a distributed sensor network for atmospheric research. The project aims to create a so-called 'planetary barometer' capable of tracking changes in the upper atmosphere over time. The work highlights an unexpected scientific use for the thousands of commercial satellites already in low Earth orbit.

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