Abstract: A method for passively stabilizing the attitude of a spinning orbiting body subject to orbital precession to maintain the spin axis orientation of the body essentially fixed and stable relative to the orbital plane. The preferred embodiment comprises selecting a body mass geometry and orbital parameters, including an orbit inclination, an orbital rate and a rate of regression of orbit line of nodes, so that the precessional motion of the body and the orbit are equal and opposite in direction and locating the spin axis of the body in a plane containing the north axis of the body and the orbit normal and between the north axis and the orbit normal, so that the gravity gradient precession of the spin axis equals the regressional motion of the orbit normal to produce a planar equilibrium configuration.

Abstract: A spin-stabilized vehicle comprising a body and three deployable panels. The inner ends of the panels are attached to the vehicle body at points equidistant from each other. Furthermore, the panel surfaces are covered with photovoltaic or solar cells. During transport and ascent of the vehicle, the panels are stowed in packages supported on the body of the vehicle. The packages are controllably deployed radially of the body in the presence of centrifugal force which in effect removes the panels from the packages. When deployed, the panels extend radially from the body of the vehicle. The use of three panels results in a relatively small ripple of the power supplied by the cells as the vehicle rotates thereby providing a relatively high efficiency of cell utilization. In addition, the utilization of panels which radiate radially from the body of the vehicle with storage boxes at the outer panel ends increases the spin moment of inertia improving the stability of the vehicle.