NASA's DART Mission Changes Didymos Asteroid System's Orbit in Historic Planetary Defense Test
On September 26, 2022, NASA's DART (Double Asteroid Redirection Test) impacted the asteroid Dimorphos, demonstrating the effectiveness of kinetic impact methods in planetary defense. The collision shortened Dimorphos's orbital period around its parent body, Didymos, by 33 minutes and altered the entire binary system's heliocentric orbit.
Researchers led by Rahil Makadia measured these changes through stellar occultation methods, capturing 22 events between October 2022 and March 2025. The DART impact reduced the speed of the Didymos system by approximately 11.7 micrometers per second, indicating that even small changes can accumulate over time to significantly alter trajectories, crucial for future planetary defense strategies.
