An Electrostatic Tractor: Coulomb Attraction Between a Charged Spacecraft and a 130-Metre Asteroid

This paper computes an electrostatic tractor in which a spacecraft held at 60,000 V and a 130 m asteroid of mass 2,300,693,020 kg charged to 45,000 V of opposite sign attract one another across a centre separation of 80 m. The Coulomb force of 0.0915 N gives an acceleration of 3.98e-11 m per second squared, which over 7 years delivers 8.79 mm per second against a requirement of 6.29 mm per second for a 2,500 km displacement with nine years of warning, a margin ratio of 1.4 and a computed separation of 3,494.5 km. This is a computed study of a deflection system for planetary defence, with no targeting or weapon application. It is simulated, not measured.