A determination of the coefficient J of the second harmonic in the Earth's gravitational potential from the orbit of satellite 1958 β₂

Abstract

From the secular changes in the longitude of the node and the argument of the perigee, the coefficient J in the gravitational potential function was determined to be (1.6232±.0005)×10−3. If the bounding equigeopotential surface of the earth is assumed to be an ellipsoid of revolution, this value of J implies a flattening ƒ of 1/298.32±.05.