DART Nudge: First Deliberate Change to an Asteroid’s Path

NASA’s 2022 DART impact on Dimorphos changed its orbit around Didymos by about 33 minutes, aided by ejecta’s recoil that added to the spacecraft’s push; Hera will later weigh Dimorphos and image the crater to refine the physics; the result shows a kinetic-impactor deflection is feasible with enough warning, but depends on accurately measuring the target’s mass and accounting for debris—lessons vital as new near-Earth threats, like 2024 YR4, remain on the radar.