Effect of the Earth's Magnetic Field on the Motion of an Artificial Satellite

The effect of the earth's magnetic field on the motion of an artificial satellite moving in a circular orbit in the plane of the magnetic equator of the earth is discussed. Approximate formulas for the current induced in the satellite and for the resulting induction drag are obtained. The current in a conducting satellite of an average size at an altitude of several hundred kilometers is estimated to be of the order of milliamperes. The induction drag may exceed the friction drag for satellites of large dimensions and for elongated satellites.