New views from Cassini of the bands and swirls of Saturn‘s north pole and of the clouds of Saturn’s moon Titan:
Saturn’s north polar region displays its beautiful bands and swirls, which somewhat resemble the brushwork in a watercolor painting.
Each latitudinal band represents air flowing at different speeds, and clouds at different heights, compared to neighboring bands. Where they meet and flow past each other, the bands’ interactions produce many eddies and swirls.
The northern polar region of Saturn is dominated by the famous hexagon shape (see PIA11682) which itself circumscribes the northern polar vortex – seen as a dark spot at the planet’s pole in the above image – which is understood to the be eye of a hurricane-like storm (PIA14946).
This view looks toward the sunlit side of the rings from about 20 degrees above the ring plane. The image was taken with the Cassini spacecraft wide-angle camera on Sept. 5, 2016 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 728 nanometers.
The view was obtained at a distance of approximately 890,000 miles (1.4 million kilometers) from Saturn. Image scale is 53 miles (86 kilometers) per pixel.
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.
For more information about the Cassini-Huygens mission visit saturn.jpl.nasa.gov and www.nasa.gov/cassini. The Cassini imaging team homepage is at ciclops.org.
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Watching Summer Clouds on Titan
NASA’s Cassini spacecraft watched clouds of methane moving across the far northern regions of Saturn’s largest moon, Titan, on Oct. 29 and 30, 2016.
Several sets of clouds develop, move over the surface and fade during the course of this movie sequence, which spans 11 hours, with one frame taken every 20 minutes. Most prominent are long cloud streaks that lie between 49 and 55 degrees north latitude. While the general region of cloud activity is persistent over the course of the observation, individual streaks appear to develop then fade. These clouds are measured to move at a speed of about 14 to 22 miles per hour (7 to 10 meters per second).
There are also some small clouds over the region of small lakes farther north, including a bright cloud between Neagh Lacus and Punga Mare, which fade over the course of the movie. This small grouping of clouds is moving at a speed of about 0.7 to 1.4 miles per hour (1 to 2 meters per second).
Time-lapse movies like this allow scientists to observe the dynamics of clouds as they develop, move over the surface and fade. A time-lapse movie can also help to distinguish between noise in images (for example from cosmic rays hitting the detector) and faint clouds or fog.
In 2016, Cassini has intermittently observed clouds across the northern mid-latitudes of Titan, as well as within the north polar region — an area known to contain numerous methane/ethane lakes and seas see PIA19657 and PIA17655. However, most of this year’s observations designed for cloud monitoring have been short snapshots taken days, or weeks, apart. This observation provides Cassini’s best opportunity in 2016 to study short-term cloud dynamics.
Models of Titan’s climate have predicted more cloud activity during early northern summer than what Cassini has observed so far, suggesting that the current understanding of the giant moon’s changing seasons is incomplete.
The mission will continue monitoring Titan’s weather around the 2017 summer solstice in Titan’s northern hemisphere.
The movie was acquired using the Cassini narrow-angle camera using infrared filters to make the surface and tropospheric methane clouds visible.
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.
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