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Current group: sci.astro
Seeing, touching and smelling the extraordinarily Earth-like world
| Andrew Yee | | John Curtis | | Landy |
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| | From: | Andrew Yee | | Subject: | Seeing, touching and smelling the extraordinarily Earth-like world | | Date: | Fri, 21 Jan 2005 18:13:21 -0500 |
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 | European Space Agency
Press Release No. 5-2005
Paris, France 21 January 2005
Seeing, touching and smelling the extraordinarily Earth-like world of Titan
On 14 January ESA's Huygens probe made an historic first ever descent to the
surface of Titan, 1.2 billion kilometres from Earth and the largest of Saturn's
moons. Huygens travelled to Titan as part of the joint ESA/NASA/ASI
Cassini-Huygens mission. Starting at about 150 kilometres altitude, six
multi-function instruments on board Huygens recorded data during the descent and
on the surface. The first scientific assessments of Huygens' data were presented
during a press conference at ESA head office in Paris on 21 January.
"We now have the key to understanding what shapes Titan's landscape," said Dr
Martin Tomasko, Principal Investigator for the Descent Imager-Spectral
Radiometer (DISR), adding: "Geological evidence for precipitation, erosion,
mechanical abrasion and other fluvial activity says that the physical processes
shaping Titan are much the same as those shaping Earth."
Spectacular images captured by the DISR reveal that Titan has extraordinarily
Earth-like meteorology and geology. Images have shown a complex network of
narrow drainage channels running from brighter highlands to lower, flatter, dark
regions. These channels merge into river systems running into lakebeds featuring
offshore 'islands' and 'shoals' remarkably similar to those on Earth.
Data provided in part by the Gas Chromatograph and Mass Spectrometer (GCMS) and
Surface Science Package (SSP) support Dr Tomasko's conclusions. Huygens' data
provide strong evidence for liquids flowing on Titan. However, the fluid
involved is methane, a simple organic compound that can exist as a liquid or gas
at Titan's sub-170 C temperatures, rather than water as on Earth.
Titan's rivers and lakes appear dry at the moment, but rain may have occurred
not long ago.
Deceleration and penetration data provided by the SSP indicate that the material
beneath the surface's crust has the consistency of loose sand, possibly the
result of methane rain falling on the surface over eons, or the wicking of
liquids from below towards the surface.
Heat generated by Huygens warmed the soil beneath the probe and both the GCMS
and SSP detected bursts of methane gas boiled out of surface material,
reinforcing methane's principal role in Titan's geology and atmospheric
meteorology -- forming clouds and precipitation that erodes and abrades the surface.
In addition, DISR surface images show small rounded pebbles in a dry riverbed.
Spectra measurements (colour) are consistent with a composition of dirty water
ice rather than silicate rocks. However, these are rock-like solid at Titan's
temperatures.
Titan's soil appears to consist at least in part of precipitated deposits of the
organic haze that shrouds the planet. This dark material settles out of the
atmosphere. When washed off high elevations by methane rain, it concentrates at
the bottom of the drainage channels and riverbeds contributing to the dark areas
seen in DISR images.
New, stunning evidence based on finding atmospheric argon 40 indicates that
Titan has experienced volcanic activity generating not lava, as on Earth, but
water ice and ammonia.
Thus, while many of Earth's familiar geophysical processes occur on Titan, the
chemistry involved is quite different. Instead of liquid water, Titan has liquid
methane. Instead of silicate rocks, Titan has frozen water ice. Instead of dirt,
Titan has hydrocarbon particles settling out of the atmosphere, and instead of
lava, Titanian volcanoes spew very cold ice.
Titan is an extraordinary world having Earth-like geophysical processes
operating on exotic materials in very alien conditions.
"We are really extremely excited about these results. The scientists have worked
tirelessly for the whole week because the data they have received from Huygens
are so thrilling. This is only the beginning, these data will live for many
years to come and they will keep the scientists very very busy", said
Jean-Pierre Lebreton, ESA's Huygens Project Scientist and Mission manager.
The Cassini-Huygens mission is a cooperation between NASA, ESA and ASI, the
Italian space agency. The Jet Propulsion Laboratory (JPL), a division of the
California Institute of Technology in Pasadena, is managing the mission for
NASA's Office of Space Science, Washington DC. JPL designed, developed and
assembled the Cassini orbiter while ESA operated the Huygens atmospheric probe.
For further information, please contact:
ESA Media Relations Division
Tel: +33(0)1.53.69.7155
Fax: +33(0)1.53.69.7690
Related links
* Exploring Saturn and Titan
http://www.esa.int/SPECIALS/Cassini-Huygens/index.html
* Huygens raw images
http://esamultimedia.esa.int/docs/titanraw/index.htm
* Sounds of Titan
http://www.esa.int/esaCP/SEM85Q71Y3E_index_0.html
* NASA's Cassini-Huygens site
http://saturn.jpl.nasa.gov
* Italian Space Agency (ASI)
http://www.asi.it
Related articles
* Islands, rivers and methane springs - latest images of Titan
http://www.esa.int/esaCP/SEM48881Y3E_index_0.html
* Huygens lands in Titanian mud
http://www.esa.int/esaCP/SEM5YW71Y3E_index_0.html
* View from ten kilometres high
http://www.esa.int/esaCP/SEMA6U71Y3E_index_0.html
* New images from Titan
http://www.esa.int/SPECIALS/Cassini-Huygens/SEMC8Q71Y3E_0.html
* First images from Titan
http://www.esa.int/esaCP/SEMBQO71Y3E_index_0.html
* Europe reaches new frontier -- Huygens lands on Titan
http://www.esa.int/esaCP/SEMQ1QQ3K3E_index_0.html
* Radio astronomers confirm Huygens entry in the atmosphere of Titan
http://www.esa.int/esaCP/SEM8ZK71Y3E_index_0.html
IMAGE CAPTIONS:
[Image 1:
http://www.esa.int/export/esaCP/SEMHB881Y3E_index_1.html]
This mosaic of three frames provides unprecedented detail of the high ridge area
including the flow down into a major river channel from different sources.
Credits: ESA/NASA/JPL/University of Arizona
[Image 2:
http://www.esa.int/export/esaCP/SEMHB881Y3E_index_1.html#subhead1]
A single image from the Huygens DISR instrument of a dark plain area on Titan,
seen during descent to the landing site, that indicates flow around bright
'islands'. The areas below and above the bright islands may be at different
elevations.
Credits: ESA/NASA/JPL/University of Arizona
[Image 3:
http://www.esa.int/export/esaCP/SEMHB881Y3E_index_1.html#subhead2]
A single Huygens DISR image that shows two new features on the surface of Titan.
A bright linear feature suggests an area where water ice may have been extruded
onto the surface. Also visible are short, stubby dark channels that may have
been formed by 'springs' of liquid methane rather than methane 'rain'.
Credits: ESA/NASA/JPL/University of Arizona
[Image 4:
http://www.esa.int/export/esaCP/SEMHB881Y3E_index_1.html#subhead3]
A view of Titan from the VIMS instrument on the Cassini orbiter. The Huygens
probe landed in the small red circle on the boundary of the bright and dark
regions. The size of the circle shows the field of view of the Huygens DISR
imager from an altitude of 20 kilometres.
Credits: ESA/NASA/JPL/University of Arizona
[Image 5:
http://www.esa.int/export/esaCP/SEMHB881Y3E_index_1.html#subhead4]
Panel of scientists presenting Huygens results.
Credits: ESA-P. SEBIROT
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| | From: | John Curtis | | Subject: | Re: Seeing, touching and smelling the extraordinarily Earth-like world of Titan (Forwarded) | | Date: | 22 Jan 2005 05:39:48 -0800 |
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| Andrew Yee wrote:
>
> New, stunning evidence based on finding atmospheric argon 40
indicates that
> Titan has experienced volcanic activity generating not lava, as on
Earth, but
> water ice and ammonia.
>
Basaltic lava requires liquid water to form silicates.
Granitic lava requires free oxygen to form silica.
Absence of liquid water or free oxygen from Titan's surface
suggests that silicon may be exiting the volcano in its
primordial form as silane (SiH4) ice.
Silane was detected on Jupiter and Saturn:
http://arxiv.org/PS_cache/physics/pdf/9906/9906037.pdf
John Curtis
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| | From: | Landy | | Subject: | Re: Seeing, touching and smelling the extraordinarily Earth-like world of Titan (Forwarded) | | Date: | Sun, 23 Jan 2005 09:37:32 +1100 |
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| > Basaltic lava requires liquid water to form silicates.
Nonsense. Pesence of water in the source rock (mantle
lherzolites) lowers the melting temperature but is not
necessary to form basaltic magmas. Likewise water is
not required for the crystallization of silcate minerals
from a silicate magma. A multitude of unpressurized
crystallization experiments demonstrate this.
> Granitic lava requires free oxygen to form silica.
Also nonsense. Free oxygen? Granitic magma has much
bound oxygen - no free oxygen. The silicon is already
present as silica in the magma (not lava).
Surely a more logical explanation of the lack of silcate
magmas on a plantary body is that the body contains very
little silica in the first place. Occams razor.
cheers
Bill
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