Based on the principle of compound pendulum,the measurement method and corresponding equipment for the centroidal deviation and the rotary inertia of rocket projectile were described.
On condition that the front body shape of the projectile is unchangeable,a formula is obtained for determining the relation between the optimum boattail angle and the supersonic flight region.
If the incoming projectile were a white dwarf—a superdense star that packs the mass of the sun into a body a hundredth the size—the residents of Earth would be treated to quite a fireworks show.