* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Post Info
TOPIC: Titan


L

Posts: 131433
Date:
RE: Titan
Permalink  
 


This natural colour view of Saturn's moon Titan was taken with the wide-angle camera aboard the Cassini spacecraft on the 25th August, 2009, when the spacecraft was approximately 174,000 kilometres away.

ti250809b.jpg
Expand (61kb, 1024 x 768)
Credit: NASA/JPL/Space Science Institute


This view shows the moon with a slightly darker northern hemisphere and a slightly lighter southern hemisphere. Titan's atmosphere has a seasonal hemispheric dichotomy. The switch between dark and bright occurred over the course of a year or two around the last equinox.
The image scale is 10 kilometres per pixel.

__________________


L

Posts: 131433
Date:
Permalink  
 

Cassini observes seasonal changes on Saturn's moon
Disappearing lakes evaporate away from Saturn's moon, Titan, reveals NASA's Cassini spacecraft. Cloud-piercing radar images of the haze-covered moon, presented Tuesday in a pair of studies by Alex Hayes of the California Institute of Technology and Jonathan Lunine of the University of Rome Tor Vergata, show methane lakes growing and shrinking in recent years in the moon's South Pole region, where temperatures range around -190 degrees Fahrenheit.

Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

NASA Cassini Radar Observes Seasonal Change in Titan's North Pole
Characterising seasonal variations in Titan's volatile system is a primary goal of the Cassini spacecraft's Equinox and Solstice missions. Two related studies report new observations by the Cassini radar instrument peering through Titan's thick atmosphere with repeat coverage. Images of the surface at different times show lakes shrinking and disappearing over the course of one to several Earth years. A mosaic of the south polar region, highlighting areas of observed change, is included with this release. The observations are of interest because they represent Cassini's initial glimpses into Titan's active hydrocarbon-based hydrologic cycle and can be used to test models of Titan's climate. The two related studies are presented by Alex Hayes, of the California Institute of Technology, and Dr. Jonathan Lunine, of the University of Rome Tor Vergata, at the American Astronomical Society's Division for Planetary Sciences meeting now under way in Fajardo, Puerto Rico.

Images of two areas in which small hydrologic features are observed to change. Each column shows the initial and later image of a region, in addition to a ratio which accentuates areas of change.

Hayes_PR_C hangeMosaic.pdf
Caption for Hayes_PR_ChangeMosaic.pdf: Stereographic projection of Synthetic Aperture Radar (SAR) imagery of Titan's south polar region obtained between Sep. 2005 and July 2009. The Cassini radar has observed 60% of this area and 9% has repeat coverage. Areas where changes have been detected are outlined in red.

Hayes_PR_S mallLakesChange_v2.pdf
Caption for Hayes_PR_SmallLakeChange.pdf: Areas where the Cassini radar has observed transient surface liquid in Titan's south polar region. The top two images are located near (60S, 210W) and were obtained in December 2007 and May 2009. Empty lake features are outlined in red and filled lakes, observed in the 2007 image, are outlined in cyan. The lake features disappear between observations. The bottom row consists of images near (69S, 90W) obtained in Oct. 2007 and Dec. 2008. Empty lake features observed in Dec. 2008 are outlined in red. The empty lake features in the bottom-left section of the image are dark in Oct. 2007, consistent with liquid-filled lakes. In the Dec. 2008 image the brightness of these features are indistinguishable from the empty lakes in the upper-right section of the image (which are bright in both observations), suggesting surface change.


Source California Institute of Technology

__________________


L

Posts: 131433
Date:
Permalink  
 

Global view of valleys on Titan show North-South divide
A team of international scientists led by Mirjam Langhans, from the German Aerospace Centre (DLR), will present first results of a global analysis of spatial patterns, occurrence and origin of river channels on Titan at the European Planetary Science Congress in Potsdam, Germany, on Wednesday 16 September.
To date scientists have focused their investigations on single channels due to the fact that radar and spectral data have only been captured for some narrow areas of the surface below the thick nitrogen atmosphere of this mysterious moon of Saturn. This data jigsaw puzzle is increasingly being filled in through further fly bys of Titan by NASA's Cassini spacecraft. Now, for the first time, the DLR team has developed a global perspective of the deposits of liquid hydrocarbons, such as methane and ethane, and their effected forms of erosion.
Beside the Earth, Titan is the only body in the Solar System where liquids directly have been proved to exist. The moon's exceptionally thick atmosphere, where chemical reactions occur at freezing temperatures of -179 degrees Celsius, makes this second largest moon of the Solar System of special interest for planetary science.
The DLR scientists have compiled a global map of Titan, which combines all radar data and details the surface of Titan down to 300 meters in size. Furthermore, data in near infrared wavelengths have been captured for a wide band around the equator by Cassini's Visual and Infrared Mapping Spectrometer (VIMS) with a resolution of up to 300 meters per pixel.
On this equatorial band, bright continent areas and extensive dune regions can be distinguished. Dark spots on the continent areas are of special interest, because they are supposed to be fluvial deposits. Additional radar data show channels precisely linked to them, which are dry, canyon-like, and broadly distributed.
Towards the north pole, the picture is much richer. There is a dense network of branching, active river systems similar to those on Earth. They are visible down to small tributaries on radar images and can be seen flowing into multiple lakes. Contrastingly, hardly any channels are found at the south pole.

"The observations of the extensive river structures at the north pole have led the team to a fascinating conclusion: there must be heavy and frequent rain of liquid hydrocarbons. Furthermore the measured channels provide first clues about the composition and relative age of different regions of Titan" - Mirjam Langhans.

Source

__________________


L

Posts: 131433
Date:
Permalink  
 

Global view of valleys on Titan show North-South divide

__________________


L

Posts: 131433
Date:
Permalink  
 

Exploring A Moon By Boat
The first nautical exploration of an extraterrestrial sea could come as soon as 2022, if a team of researchers can convince NASA to try sailing a boat on an alien world.

"The overwhelming reaction I get from scientists and engineers is, 'Oh, that's really cool.' I mean, people are just instantly kind of excited and intrigued to say, 'Could we really go do this?' " - Ellen Stofan, a planetary geologist at Proxemy Research in Maryland and an honorary professor at University College London.

Source

__________________


L

Posts: 131433
Date:
Permalink  
 

Unravelling the Chemistry of Titan's Hazy Atmosphere
Research study provides information about how a key molecule in Titan's atmosphere may be formed and offers clues to the evolution of Titan's and Earth's atmospheres


Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

UH Manoa team unravels the chemistry of Titan's hazy atmosphere
A team of University of Hawai'i at Mnoa researchers led by Ralf Kaiser, physical chemist at UH Manoa, unravelled the chemical evolution of the orange-brownish coloured atmosphere of Saturn's moon Titan, the only solar system body besides Venus and Earth with a solid surface and thick atmosphere. The UH Manoa team, including Xibin Gu and Seol Kim, conducted simulation experiments mimicking the chemical reactions in Titan's atmosphere utilising crossed molecular beams in which the consequence of a single collision between molecules can be followed.

Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

Since its discovery by Dutch astronomer Christiaan Huygens in 1655, Saturn's most massive moon, Titan, has been known as a place of mystery and intrigue. The large, cloud-enshrouded moon is such a scientific enigma that for the past five years, it has been targeted by NASA's Cassini spacecraft with more than 60 probing flybys. One of its latest findings could be a valuable asset to future generations of space explorers hunting for materials to whip up a barbecue.

"Titan's atmosphere is extremely rich in an assortment of hydrocarbon chemicals, including propane, which we use to fill our barbecue tanks. Titan's atmospheric inventory would fuel about 150 billion barbecue cookouts" - Cassini scientist Conor Nixon of the University of Maryland, College Park.

Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

Astronomer finds evidence of weather on Titan
Saturns moon, Titan, has long been the subject of excited rumours about possible extra-terrestrial life, and now it seems that the moon is shrouded in fog as well as mystery.

"Look! Titan has fog at the south pole. I first realised this a year ago, but it took me until now to finally have the time to be able to put all of the pieces together into a scientific paper that is convincing enough that I can now go up to any person in the street and say: Titan has fog at the south pole!" - Astronomer Mike Brown.

Read more

__________________
«First  <  112 13 14 15 1649  >  Last»  | Page of 49  sorted by
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard