NASA has released a series of images taken by the Cassini spacecraft of the huge hurricane in progress at the north pole of the planet Saturn. The eye of this hurricane has a width of about 2,000 km (1,250 miles), about 20 times the average of the hurricanes on Earth, and the winds at its edges reach a speed of around 530 km/h (330 mph).
Hurricanes on Saturn have several characteristics in common with those on Earth such as the presence of clouds in certain areas but there are also substantial differences. The hurricane at the north pole of Saturn shows how on this planet hurricanes are larger and spin faster than the Earth’s ones. On Earth, hurricanes tend to move towards north due to the forces acting on its swirls as the planet rotates while the hurricane on Saturn is locked at the north pole so it can’t go anywhere.
According to the scientists who are studying this hurricane, it has existed for years but the Cassini spacecraft reached the Saturn system in 2004, when its north pole was in darkness because it was winter in its northern hemisphere. Two instruments of the probe, the Composite Infrared Spectrometer (CIRS) and the Visible and Infrared Mapping Spectrometer (VIMS), detected the presence of a large vortex in infrared light but only in August 2009, when there was the equinox on Saturn, it was possible to give it a look at visible light.
A closer study of that big hurricane at the North Pole took a long time because of the Cassini spacecraft’s orbit. Saturn’s polar regions can’t be observed very well from an equatorial orbit so it was necessary to wait for Cassini to move to a more favorable orbit, a slow process that was planned carefully and well in advance.
The Cassini spacecraft has a certain amount of hydrazine to be used as propellant for the maneuvers that bring it near specific areas of the planet Saturn or its satellites but also uses the satellite Titan’s gravity to help in its maneuvers when it flies near it. Eventually, last year Cassini passed over the polar area of the planet and its narrow-angle camera (NAC) took a series of photographs using a combination of spectral filters sensitive to near-infrared wavelengths.
In addition to confirming once again that the Saturn system is really extraordinary, the study of the hurricane at the north pole of the planet will help to improve our knowledge about hurricanes in general, including the Earth’s ones that draw energy from the warm ocean waters.
[ad name=”Google Adsense 468″]
Permalink