Donna Calhoun, a professor of mathematics, recently concluded her involvement in the Defense Advanced Research Projects Agency’s Atmosphere as a Sensor program, called AtmoSense for short.
“AtmoSense, which began in late 2020, set out to understand the fundamentals of energy propagation from the Earth’s surface to the ionosphere to determine whether the atmosphere can be used as a sensor,” the agency wrote.
The project could help detect natural events, like earthquakes or volcanic eruptions, and manmade atmospheric disturbances, like underground explosions. At one point during testing in 2024, the team detected SpaceX Falcon 9 re-entries, something they hadn’t expected to see.
Calhoun served as the main developer on the software used to run the simulations that detect signals seen in the atmosphere from various terrestrial and space events.
The AtmoSense group shared its results with the defense and scientific communities at a hybrid in-person and virtual workshop April 15-17, 2025, in Daytona Beach, Florida.