Science. 1990 Mar 9;247(4947):1206-8. doi: 10.1126/science.247.4947.1206.
The rotation rates of the interiors of the outer planets are normally derived from their periodic radio emissions. However, recent observations of both Jupiter and Saturn have revealed surface features with periods close to those derived for the interiors. In the study reported here, this process is carried one stage further, with the derivation of a rotation rate for the spot associated with Satum's polar hexagon, which is simultaneously within and more accurate than the Saturnian radio period.
外行星内部的自转速度通常是通过它们的周期性射电辐射来推断的。然而，最近对木星和土星的观测揭示了一些表面特征，其周期与从内部推断出的周期非常接近。在本研究中，这个过程又向前推进了一步，推导出了与土星极区六边形相关的斑点的自转速度，这个速度既在土星的射电周期内，又比土星的射电周期更准确。
