A Solar Concentrator for Asteroid Deflection: Passive Collection and Surface Sublimation on a 90-Metre Body

This paper computes a deflection system that collects sunlight with a 12 m2 mirror of diameter 3.91 m and focuses 10,126 W onto the surface of a 90 m asteroid of mass 839,747,716 kg. The resulting mass flow of 0.000563 kg per second yields 0.534 N of sublimation recoil and an acceleration of 6.36e-10 m per second squared. Over 2.6 years the system delivers 52.2 mm per second against a requirement of 24.5 mm per second for a 6,500 km displacement with six years of warning, a margin ratio of 2.13 and a computed separation of 13,842 km. This is a computed study of a deflection system for planetary defence, with no targeting or weapon application. It is simulated, not measured.