Titan Images 2017
|The three images of this table correspond to raw views or
unprocessed images of Saturn's largest moon Titan obtained from the
Cassini spacecraft during the final close flyby of the Opaque Moon on
April 21, 2017. From outer space, one can notice surface features on Titan
in the infrared or near-infrared spectrum. The Titanian atmosphere appears
completely opaque in the visible spectrum. The relatively dark areas found
at low latitudes are dominated by Seif Dunes. Lakes, seas and rivers turn
out to be concentrated in the high latitudes or in the polar regions of
the Orange Moon. In the upper view, one can notice the dark regions of
Fensal and Aztlan. Are Fensal and Aztlan the remnants of ancient seas of
liquid methane or liquid ethane ? How can we explain the dichotomy in the
distribution of surface liquids between the south polar region and the
north polar region or between the low latitudes and the high latitudes ?
Is the hazy atmosphere of the giant moon stable over time ?
Credit for the images: NASA/JPL-Caltech/Space Science Institute.
|This image corresponds to a mosaic view revealing the
lakes and seas located in the high latitudes of the northern hemisphere of
Saturn's largest moon Titan. The images used to assemble this mosaic view
were obtained on February 17, 2017 from the Narrow-Angle Camera of the
Cassini probe during a relatively distant encounter with the Opaque Moon
as the spacecraft was speeding away from Titan. The image was acquired at
a distance of about 150,700 miles or 242,500 kilometers from the giant
moon. The views were captured with a spectral filter sensitive to
wavelengths of near-infrared radiation centered at 938 nanometers. At this
wavelength, one can see through the opaque atmosphere of Titan and discern
landscape features, lakes, seas and even clouds. The image represents an
orthographic projection centered on 68 degrees north latitude and 225
degrees west longitude. An orthographic image is roughly similar to the
image seen by a distant watcher observing with a telescope.
The mosaic view clearly shows the land of lakes, seas and rivers found in the high latitudes of the northern hemisphere. Kraken Mare, Ligeia Mare and Punga Mare can be clearly discerned here. One can notice several prominent cloud streaks evolving at mid-latitudes between 45 and 55 degrees north latitude to the right of the image. A bright cloud patch can also be identified in the area of the lake or sea Punga Mare found to the right of Kraken Mare roughly at center. During this distant encounter, the viewing angle over Kraken Mare and its neighboring pool of liquid hydrocarbons Ligeia Mare appeared better than during previous flybys with a higher contrast so that more details could be discerned regarding landscape features and the shorelines or the boundaries of the surface bodies of liquid. The solar radiations had to go through less haze to reach the lakes or seas and to bounce toward the eye of the Cassini spacecraft. That's why the quality of the image appeared better this time than during previous passes.
This encounter represented one of several "non-targeted" passes of the Opaque Moon in 2017 that enable researchers to monitor and analyze cloud activity in the high latitudes of the northern hemisphere. The engineers did not have to use rocket-thruster firings to orientate the probe for this flyby. The Spring season in the northern hemisphere is about to end and the Summer season in the northern hemisphere is approaching. Does this period of transition imply significant changes in cloud activity in the north polar region ? Probably because researchers are now observing increasing cloud activity in the north polar region. However, some models regarding Titan's meteorology or atmosphere had predicted more cloud activity than what scientists currently observe.
Image Credit: NASA/JPL-Caltech/Space Science Institute.
|The image above reveals, in particular, several elongated
cloud patches evolving around the north polar region of Saturn's largest
moon Titan. One can also notice the famous land of lakes and seas which
appear relatively dark and uniform in this view. Titan's northern
hemisphere is now experiencing the end of the Spring season. The long
Summer season in the area will start very soon during the year of 2017.
The lakes, seas or rivers may be mainly composed of methane, a simple
hydrocarbon. The wispy clouds appear at high altitudes and at high
latitudes. Researchers have noticed an increase in the amount or in the
concentration of clouds in the area but they had expected the development
of more clouds or larger cloud formations in this seasonal configuration.
The sky of the Opaque Moon in the high latitudes of the northern
hemisphere is surprisingly clear in this period of the Titanian year.
Clouds are remarkably dynamic or sporadic. Researchers try to regularly
monitor the atmosphere or the meteorology of Titan in order to have a
correct insight into the level of cloud activity. Are the amount of clouds,
the concentration of clouds or the distribution of clouds in line with the
predictions of the prevailing meteorological model of Titan ?
The view was acquired with the Narrow-Angle Camera of the Cassini probe on October 29, 2016 using a spectral filter sensitive to wavelengths of near-infrared radiation centered at 938 nanometers. The camera is orientated toward the Saturn-facing side of the Hazy Moon. North appears upward and is inclined 3 degrees to the left. The image of Titan's disk was taken at a distance of about 545,000 miles or 878,000 kilometers from the Opaque Moon. The infrared or near-infrared views allow us to discern surface features as well as clouds. One can also notice in this view the dark low-latitude areas which tend to be dominated by Seif Dunes or parallel and linear dunes extending over long distances under the influence of prevailing winds.
Image Credit: NASA/JPL-Caltech/Space Science Institute.
Titan Images 2016
Titan Images 2015
Titan Images 2014
Titan Images 2013
Titan Images 2012
Titan Images 2011
Titan Images 2010
Titan Images 2009
Titan Images 2008
Titan Images 2007
Titan Images 2006
Titan Images 2005, 2004
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