Circles And Hexagons

Image Credit: NASA/JPL-Caltech/Space Science Institute

October 9, 2017 – Saturn’s cloud belts generally move around the planet in a circular path, but one feature is slightly different. The planet’s wandering, hexagon-shaped polar jet stream breaks the mold — a reminder that surprises lurk everywhere in the solar system.

This atmospheric feature was first observed by the Voyager mission in the early 1980s, and was dubbed “the hexagon.” Cassini’s visual and infrared mapping spectrometer was first to spy the hexagon during the mission, since it could see the feature’s outline while the pole was still immersed in wintry darkness. The hexagon became visible to Cassini’s imaging cameras as sunlight returned to the northern hemisphere.

This view looks toward the northern hemisphere of Saturn — in summer when this view was acquired — from above 65 degrees north latitude. The image was taken with the Cassini spacecraft wide-angle camera on June 28, 2017 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 752 nanometers.

The view was acquired at a distance of approximately 536,000 miles (862,000 kilometers) from Saturn. Image scale is 32 miles (52 kilometers) per pixel.

The Cassini spacecraft ended its mission on September 15, 2017.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.