Het persbericht van de ESA:
Seeing, touching and smelling the extraordinarily Earth-like world of Titan
21 January 2005 - ESA PR 05-2005.
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.
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.
Bron: http://www.esa.int/SPECIALS/Cassini-Huygens/
En hier een bericht van nu.nl:
Rivieren te zien op foto's Saturnus-maan Titan
Uitgegeven: 21 januari 2005 13:34
Laatst gewijzigd: 21 januari 2005 14:58
AMSTERDAM - Een door erosie ontstaan landschap met afvloeiingskanalen en objecten die op stenen lijken op de oppervlakte. Op Titan is eveneens vulkanische activiteit. De vulkanen spuwen geen lava, maar ijs en ammonia. Dit zijn de eerste indrukken van wetenschappers na het bestuderen van de door ruimtesonde Huygens genomen foto's van Saturnus-maan Titan.
Op 14 januari daalde de Huygens-sonde van de Europese ruimtevaartorganisatie ESA af in de dikke atmosfeer van Saturnus-maan Titan. De sonde remde precies zoals gepland met hitteschild en parachutes en begon zijn meetgegevens te verzenden. In drie uur en 44 minuten verzond Huygens meer dan 474 megabits gegevens.
Blunder
Het was de bedoeling dat de NASA-sonde Cassini het zwakke radiosignaal van Huygens op zou vangen om het vervolgens door te sturen naar de aarde. Door een blunder van ESA negeerde Cassini echter alle data die over één van de twee communicatiekanalen binnenkwamen.
Schakelaar
"Het was niet ingewikkelder geweest dan een schakelaar omgooien," gaf ESA's onderzoeksdirecteur David Southwood toe. "NASA's Cassini heeft alle computeropdrachten die wij leverden perfect uitgevoerd, maar wij zijn de instructie om kanaal A open te zetten vergeten." Door het communicatieprobleem met Cassini ging niet alleen de helft van Huygens' panoramafoto's verloren, maar ook een meting om Huygens' afdaling door de Titan-atmosfeer te volgen mislukte.
Nederlandse astronomen van het JIVE (Joint Institute for VLBI in Europe) gaan nu redden wat er te redden valt. "Met onze metingen kunnen we plaats en snelheid van Huygens van moment tot moment reconstrueren", legt JIVE-astronoom Huib Jan van Langevelde uit op de populair-wetenschappelijke website Kennislink uit.
"Titan's atmosfeer is vooral interessant omdat het een ingevroren versie is van onze eigen atmosfeer", weet Van Langevelde. Op onze aarde ontwikkelde zich leven dat de chemische samenstelling van onze eigen oeratmosfeer compleet veranderde, maar op Titan is het oorspronkelijke mengsel van onder andere stikstof en methaan nog aanwezig.
Seeing, touching and smelling the extraordinarily Earth-like world of Titan
21 January 2005 - ESA PR 05-2005.
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.
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.
Bron: http://www.esa.int/SPECIALS/Cassini-Huygens/
En hier een bericht van nu.nl:
Rivieren te zien op foto's Saturnus-maan Titan
Uitgegeven: 21 januari 2005 13:34
Laatst gewijzigd: 21 januari 2005 14:58
AMSTERDAM - Een door erosie ontstaan landschap met afvloeiingskanalen en objecten die op stenen lijken op de oppervlakte. Op Titan is eveneens vulkanische activiteit. De vulkanen spuwen geen lava, maar ijs en ammonia. Dit zijn de eerste indrukken van wetenschappers na het bestuderen van de door ruimtesonde Huygens genomen foto's van Saturnus-maan Titan.
Op 14 januari daalde de Huygens-sonde van de Europese ruimtevaartorganisatie ESA af in de dikke atmosfeer van Saturnus-maan Titan. De sonde remde precies zoals gepland met hitteschild en parachutes en begon zijn meetgegevens te verzenden. In drie uur en 44 minuten verzond Huygens meer dan 474 megabits gegevens.
Blunder
Het was de bedoeling dat de NASA-sonde Cassini het zwakke radiosignaal van Huygens op zou vangen om het vervolgens door te sturen naar de aarde. Door een blunder van ESA negeerde Cassini echter alle data die over één van de twee communicatiekanalen binnenkwamen.
Schakelaar
"Het was niet ingewikkelder geweest dan een schakelaar omgooien," gaf ESA's onderzoeksdirecteur David Southwood toe. "NASA's Cassini heeft alle computeropdrachten die wij leverden perfect uitgevoerd, maar wij zijn de instructie om kanaal A open te zetten vergeten." Door het communicatieprobleem met Cassini ging niet alleen de helft van Huygens' panoramafoto's verloren, maar ook een meting om Huygens' afdaling door de Titan-atmosfeer te volgen mislukte.
Nederlandse astronomen van het JIVE (Joint Institute for VLBI in Europe) gaan nu redden wat er te redden valt. "Met onze metingen kunnen we plaats en snelheid van Huygens van moment tot moment reconstrueren", legt JIVE-astronoom Huib Jan van Langevelde uit op de populair-wetenschappelijke website Kennislink uit.
"Titan's atmosfeer is vooral interessant omdat het een ingevroren versie is van onze eigen atmosfeer", weet Van Langevelde. Op onze aarde ontwikkelde zich leven dat de chemische samenstelling van onze eigen oeratmosfeer compleet veranderde, maar op Titan is het oorspronkelijke mengsel van onder andere stikstof en methaan nog aanwezig.
Bericht laatst bijgewerkt: 21-01-2005 16:02
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