Three-Body Problem and an Unrecognized Oscillatory Motion of the Earth

Building on the classical three-body problem, this paper introduces the concept of a ”center of acceleration” in the Sun–Earth–Moon system. This center is shown to move with the frequency of the Moon’s orbit and induces an additional radial oscillation in the Earth’s trajectory, independent of barycentric motion. Using Dopplergram data from the Solar Dynamics Observatory (SDO), this oscillation was measured to have an amplitude exceeding 25,000 kilometers.