Saturn’s “mysterious hexagon” turns gold from blue after the last 4 years and nobody has an answer to why.
Said to be a mystery, this 32,190km (20,000 miles) wide hexagon in Saturn’s north pole was first seen 30 yrs ago, by Voyager Mission in 1981-1982, and revisited since 2006 by the Cassini mission. Its size is twice the diameter of Earth and is said to be made of band of upper atmospheric wind with polar cyclone in the center. Along the rim of the hexagon, is a jet stream of air, blasting eastward at speeds of 321km/hr (200 mph).It rotates at the same rate the Saturn rotates on its axis 10hr 39m 24s and have no longitudinal shift like other clouds in the atmosphere.
Image Credit: NASA/JPL-Caltech/Space Sci 1
These two natural color images from NASA’s Cassini spacecraft show the changing appearance of Saturn’s North Polar Region between 2012 and 2016.
Scientists are investigating potential causes for the change in color of the region inside the north-polar hexagon on Saturn. The color change is thought to be an effect of Saturn’s seasons. In particular, the change from a bluish color to a more golden hue may be due to the increased production of photochemical hazes in the atmosphere as the north pole approaches summer solstice in May 2017,” NASA says.
Researchers think the hexagon, which is a six-sided jet stream, might act as a barrier that prevents haze particles produced outside it from entering. During the polar winter night between November 1995 and August 2009, Saturn’s north polar atmosphere became clear of aerosols produced by photochemical reactions — reactions involving sunlight and the atmosphere. Since the planet experienced equinox in August 2009, the polar atmosphere has been basking in continuous sunshine, and aerosols are being produced inside of the hexagon, around the north pole, making the polar atmosphere appear hazy today.
Other effects, including changes in atmospheric circulation, could also be playing a role. Scientists think seasonally shifting patterns of solar heating probably influence the winds in the Polar Regions.
Both images were taken by the Cassini wide-angle camera.
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 Caltech 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.
For more of Saturn, here’s a video of its hexagonal storm.