Jupiter's Decametric Rotation Period

The mean value of Jupiter's rotation period over an assumed 11.86-year drift cycle was found to be 9h55m29 ~73 ± 0 s04. The position of source A in a central-meridian-longitude system based on the new rotation period displayed a correlation with the Jovicentric declination of the Earth distinctly higher than its anticorrelation with the sunspot number, substantiating an earlier suggestion that the observed drift is a geometrical effect due to Jupiter's changing aspect in its orbit around the Sun. A model consist- ing of a single curved emission sheet fixed to the magnetic field can be made to account for the observed drifts of sources A and B