Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

First ’in situ’ composition measurements made in Titan’s atmosphere

01.12.2005


Unique results from the Aerosol Collector and Pyrolyser (ACP) and the Gas Chromatograph Mass Spectrometer (GCMS) have given scientists their first in situ chemical data on Titan’s atmosphere, including aerosols, chemical composition and isotopes.



Two of Titan’s key unknowns are the origin of the molecular nitrogen and methane in the atmosphere, and the mechanisms by which methane is maintained in the face of rapid destruction by photochemistry (chemical processes that are accompanied by or catalysed by the emission or absorption of visible or ultraviolet light).

The GCMS measured chemical composition and isotope abundances from 140 km altitude to the surface and confirmed the primary constituents were nitrogen and methane, and that the haze in the atmosphere is primarily methane.


From isotopic ratio measurements, the Huygens scientists obtained two key findings. The carbon isotope ratio (12C/13C) measured in methane suggests a continuous or periodic replenishment of methane in the atmosphere, but no evidence was found of active biological systems.

The nitrogen isotope ratio (14N/15N) suggests to the scientists that the early atmosphere of Titan was five times denser than it is now, and hence lost nitrogen to space.

Argon 36 was detected for the first time, but not xenon or krypton. However, the argon was found in low abundance, which is especially interesting because of the huge, nitrogen-dominated atmosphere and because about 50% of the mass of Titan is water ice, known to be a potentially efficient carrier of noble gases.

This low abundance implies the atmosphere was condensed or captured as ammonia, instead of nitrogen. The non-detection of the other noble gases, a surprising finding, will also fuel theories of the origin and evolution of Titan’s atmosphere.

The composition of surface vapours obtained by GCMS after landing shows that Huygens landed on a surface wet with methane, which evaporated as the cold soil was heated by the warmer probe. The surface was also rich in organic compounds not seen in the atmosphere, for example cyanogen and ethane, indicating a complex chemistry on Titan’s surface as well as in the atmosphere.

Argon 40 was also detected at the surface and its presence indicates that Titan has experienced in the past, and is most likely still experiencing today, internal geological activity.

Titan’s aerosols play an important role in determining atmospheric thermal structure, affecting the processes of radiative heating and cooling. They can help to create warm and cold layers that in turn contribute to circulation patterns and determine the strengths of winds.

The ACP obtained direct measurements of the chemical make-up of these aerosol particles. From an analysis of the products obtained by pyrolysis (chemical decomposition of organic materials by heating) of aerosols at 600°C, ammonia and hydrogen cyanide were the first molecules identified.

This is of prime importance because ammonia is not present as a gas in the atmosphere, hence the aerosols must include the results of chemical reactions that may have produced complex organic molecules. They are not simply condensates.

Aerosol particles may also act as condensation nuclei for cloud formation, and are the end-products of a complex organic chemistry which is important in astrobiology. Indeed, Titan offers the possibility to observe chemical pathways involving molecules that may have been the building blocks of life on Earth.

Franco Bonacina | alfa
Further information:
http://www.esa.int/SPECIALS/Results_from_Mars_Express_and_Huygens/SEMK1TULWFE_0.html

More articles from Earth Sciences:

nachricht A promising target in the quest for a 1-million-year-old Antarctic ice core
24.05.2018 | University of Washington

nachricht Tropical Peat Swamps: Restoration of Endangered Carbon Reservoirs
24.05.2018 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>