For billions of years Earth has absorbed whatever the solar system threw at it. On September 26, 2022 humanity hit back. This episode explains NASA's Double Asteroid Redirection Test, why kinetic impact beat alternatives like gravity tractors and laser ablation, and why the Didymos binary system was the perfect target: a 780 meter primary orbited every 11 hours 55 minutes by the 160 meter moonlet Dimorphos, 6.8 million miles away and no threat to Earth. The hosts describe how photometric light curves let astronomers time the moonlet's orbit like a moth circling a porch light, and why blowing up an asteroid would turn one bullet into an unpredictable shotgun blast.

The episode walks through the 610 kilogram spacecraft, its DRACO camera and SMART Nav autonomy derived from missile technology, the Italian LICIACube that trailed three minutes be ...