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Charles Gammie and colleagues wrote the HARM code to tackle the extreme physics close to a spinning black hole. Twenty years later, it is performing a similar task in three dimensions in 1/10,000th of the time.
James Stone started developing Athena in the mid-2000s, building on several years’ work on numerical methods for compressible magnetohydrodynamics in shocks. A couple of incarnations later, AthenaK is ready to face the exascale computing future.
Gary Ferland has been developing the photoionization code Cloudy for 45 years. The model has steadily been expanding in its coverage of parameter space, and focuses on the microphysics of irradiated environments.
