NASA's DART spacecraft successfully altered the orbital path of asteroid Didymos around the Sun by impacting its moonlet Dimorphos in September 2022, marking the first human-made change to a celestial body's heliocentric orbit and validating kinetic impact as a planetary defense technique.
NASA's DART spacecraft successfully altered the orbital velocity of asteroid Dimorphos by impacting it in 2022, reducing its 12-hour orbit around its larger companion Didymos by 32 minutes—the first human-caused change to a celestial object's orbit. Follow-up observations using stellar occultations confirmed the impact also changed the asteroids' joint orbit around the sun by approximately 150 milliseconds, with implications for future planetary defense strategies.