A method of estimating spin rate, coning rate, and coning half-angle of a spinning space vehicle using the data from a single-axis magnetometer mounted transversely on spin axis of the vehicle was described. In addition, estimates were available for the angle between total annular momentum vector of the vehicle and local magnetic field vector. Hybrid optimization strategy and a mathematical model of rotary projectile were used; the model contains genetic algorithm and gradient optimization, for the genetic algorithm's character of global optimization and gradient optimization's character of searched ability local region. This method was verified to have feasibility by experiment.