Successful Kinetic Impact into an Asteroid for Planetary Defense

NASA’s Double Asteroid Redirection Test (DART) mission is the first full-scale test of a technology to deflect an asteroid. While no known asteroid poses a threat to Earth for at least the next century, the catalog of near-Earth asteroids is incomplete for the size of objects that would produce regional devastation if such an impact occurred1,2. An experimental test of a kinetic impactor was identified as the highest priority space mission related to asteroid deflection or disruption1. Here we report the first demonstration of an autonomous kinetic impact into a near-Earth asteroid called Dimorphos, whose size is representative of asteroids to which we remain vulnerable due to current deficiencies in the asteroid catalog3. While past missions have utilized impactors to investigate the properties of small bodies4,5, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. The successful impact of the DART spacecraft with Dimorphos and the resulting change in Dimorphos's orbit6 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if we one day discover an asteroid threat.