Early hexagon images from Voyager and ground-based telescopes suffered from poor viewing perspectives. Cassini, which has been orbiting Saturn since 2004, has a better angle for viewing the north pole. But the long darkness of Saturnian winter hid the hexagon from Cassini’s visible-light cameras for years. Infrared instruments, however, were able to obtain images by using heat patterns. Those images showed the hexagon is nearly stationary and extends deep into the atmosphere. They also discovered a hotspot and cyclone in the same region.
A precise value for the rotation period of the interior remains elusive. While approaching Saturn in 2004, Cassini found that the radio rotation period of Saturn had increased appreciably, to approximately 10 hr 45 min 45 sec (± 36 sec). The latest estimate of Saturn's rotation (as an indicated rotation rate for Saturn as a whole) based on a compilation of various measurements from the Cassini, Voyager and Pioneer probes was reported in September 2007 is 10 hr 32 min 35 sec.
The has been orbiting Saturn since 2004, and the mission is expected to come to a close in September 2017. Researchers will continue to study data collected from Cassini to get a better understanding of this curious color change.
I’m nostalgic already about the , which has been orbiting Saturn since 2004 and which is now in its final year. And it seems I’m not the only one. In a statement during last week’s joint of the Division for Planetary Sciences and European Planetary Science Congress (October 16-21, 2016) – in Pasadena, California, space scientist of the Observatoire de Paris and her team also sounded nostalgic about Cassini and how it has let us track the changing seasons on Saturn’s largest moon, Titan. These scientists said: