Spinning Slower: How the DART Impact Changed Asteroid Didymos

Researchers analyzed twenty years of light-curve data to determine that asteroid Didymos slowed its rotation by 0.18 seconds after the DART impact. This change, confirmed through detailed modeling and bootstrap tests, is best explained by slight reshaping of the asteroid, likely small landslides triggered by falling ejecta. The result provides new insight into how kinetic-impact missions can alter not just orbits but also asteroid spin states.