Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA's Cassini Sees Abrupt Turn in Titan's Atmosphere

29.11.2012
Data from NASA's Cassini spacecraft tie a shift in seasonal sunlight to a wholesale reversal, at unexpected altitudes, in the circulation of the atmosphere of Saturn's moon Titan.

At the south pole, the data show definitive evidence for sinking air where it was upwelling earlier in the mission. So the key to circulation in the atmosphere of Saturn's moon Titan turned out to be a certain slant of light. The paper was published today in the journal Nature.


This artist's impression of Saturn's moon Titan shows the change in observed atmospheric effects before, during and after equinox in 2009. Image credit: ESA

"Cassini's up-close observations are likely the only ones we'll have in our lifetime of a transition like this in action," said Nick Teanby, the study's lead author who is based at the University of Bristol, England, and is a Cassini team associate. "It's extremely exciting to see such rapid changes on a body that usually changes so slowly and has a 'year' that is the equivalent of nearly 30 Earth years."

In our solar system, only Earth, Venus, Mars and Titan have both a solid surface and a substantial atmosphere - providing natural laboratories for exploring climate processes. "Understanding Titan's atmosphere gives us clues for understanding our own complex atmosphere," said Scott Edgington, Cassini deputy project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Some of the complexity in both places arises from the interplay of atmospheric circulation and chemistry."

The pole on Titan that is experiencing winter is typically pointed away from Earth due to orbital geometry. Because Cassini has been in orbit around Saturn since 2004, it has been able to study the moon from angles impossible from Earth and watch changes develop over time. Models have predicted circulation changes for nearly 20 years, but Cassini has finally directly observed them happening - marking a major milestone in the mission.

Other Cassini instruments recently obtained images of the formation of haze and a vortex over Titan's south pole, but the data from the composite infrared spectrometer (CIRS) is sensitive to much higher altitudes, provides more quantitative information and more directly probes the circulation and chemistry. The CIRS data, which enable scientists to track changes in atmospheric temperature and the distribution of gases like benzene and hydrogen cyanide, also revealed changes in hard-to-detect vertical winds and global circulation.

Besides the evidence for sinking air, Cassini also detected complex chemical production in the atmosphere at up to 400 miles (600 kilometers) above the surface, revealing the atmospheric circulation extends about 60 miles (100 kilometers) higher than previously expected. Compression of this sinking air as it moved to lower altitudes produced a hot spot hovering high above the south pole, the first indication of big changes to come. The scientists were also able to see very rapid changes in the atmosphere and pinpoint the circulation reversal to about six months around the August 2009 equinox, when the sun shone directly over Titan's equator. The circulation change meant that within two years of equinox, some gases had increased in abundance 100-fold - much more extreme than anything seen so far on Titan.

The results also suggest that a detached layer of haze (first detected by NASA's Voyager spacecraft) may not be so detached after all, since complex chemistry and vertical atmospheric movement is occurring above this layer. This layer may instead be the region where small haze particles combine into larger, but more transparent, clumped aggregates that eventually descend deeper into the atmosphere and give Titan its characteristic orange appearance.

"Next, we would expect to see the vortex over the south pole build up," said Mike Flasar, the CIRS principal investigator at NASA's Goddard Space Flight Center in Greenbelt, Md. "As that happens, one question is whether the south winter pole will be the identical twin of the north winter pole, or will it have a distinct personality? The most important thing is to be able to keep watching as these changes happen."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory manages the mission for NASA's Science Mission Directorate, Washington, D.C. The visual and infrared mapping spectrometer team is based at the University of Arizona, Tucson. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center in Greenbelt, Md., where the instrument was built. JPL is a division of Caltech.

For more information on Cassini, visit http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov .

Jia-Rui Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jccook@jpl.nasa.gov
Elizabeth Zubritsky/Nancy Neal-Jones 301-614-5438/301-286-0039
Goddard Space Flight Center, Greenbelt, Md.
elizabeth.a.zubritsky@nasa.gov /nancy.n.jones@nasa.gov

Elizabeth Zubritsky | EurekAlert!
Further information:
http://www.nasa.gov/cassini
http://saturn.jpl.nasa.gov .
http://www.nasa.gov/mission_pages/cassini/whycassini/cassini20121128.html

More articles from Physics and Astronomy:

nachricht Donuts, math, and superdense teleportation of quantum information
29.05.2015 | University of Illinois College of Engineering

nachricht Physicists precisely measure interaction between atoms and carbon surfaces
29.05.2015 | University of Washington

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Lasers are the key to mastering challenges in lightweight construction

Many joining and cutting processes are possible only with lasers. New technologies make it possible to manufacture metal components with hollow structures that are significantly lighter and yet just as stable as solid components. In addition, lasers can be used to combine various lightweight construction materials and steels with each other. The Fraunhofer Institute for Laser Technology ILT in Aachen is presenting a range of such solutions at the LASER World of Photonics trade fair from June 22 to 25, 2015 in Munich, Germany, (Hall A3, Stand 121).

Lightweight construction materials are popular: aluminum is used in the bodywork of cars, for example, and aircraft fuselages already consist in large part of...

Im Focus: Solid-state photonics goes extreme ultraviolet

Using ultrashort laser pulses, scientists in Max Planck Institute of Quantum Optics have demonstrated the emission of extreme ultraviolet radiation from thin dielectric films and have investigated the underlying mechanisms.

In 1961, only shortly after the invention of the first laser, scientists exposed silicon dioxide crystals (also known as quartz) to an intense ruby laser to...

Im Focus: Advance in regenerative medicine

The only professorship in Germany to date, one master's programme, one laboratory with worldwide unique equipment and the corresponding research results: The University of Würzburg is leading in the field of biofabrication.

Paul Dalton is presently the only professor of biofabrication in Germany. About a year ago, the Australian researcher relocated to the Würzburg department for...

Im Focus: Basel Physicists Develop Efficient Method of Signal Transmission from Nanocomponents

Physicists have developed an innovative method that could enable the efficient use of nanocomponents in electronic circuits. To achieve this, they have developed a layout in which a nanocomponent is connected to two electrical conductors, which uncouple the electrical signal in a highly efficient manner. The scientists at the Department of Physics and the Swiss Nanoscience Institute at the University of Basel have published their results in the scientific journal “Nature Communications” together with their colleagues from ETH Zurich.

Electronic components are becoming smaller and smaller. Components measuring just a few nanometers – the size of around ten atoms – are already being produced...

Im Focus: IoT-based Advanced Automobile Parking Navigation System

Development and implementation of an advanced automobile parking navigation platform for parking services

To fulfill the requirements of the industry, PolyU researchers developed the Advanced Automobile Parking Navigation Platform, which includes smart devices,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International symposium: trends in spatial analysis and modelling for a more sustainable land use

20.05.2015 | Event News

15th conference of the International Association of Colloid and Interface Scientists

18.05.2015 | Event News

EHFG 2015: Securing health in Europe. Balancing priorities, sharing responsibilities

12.05.2015 | Event News

 
Latest News

Quasi-sexual gene transfer drives genetic diversity of hot spring bacteria

29.05.2015 | Life Sciences

First Eastern Pacific tropical depression runs ahead of dawn

29.05.2015 | Earth Sciences

Donuts, math, and superdense teleportation of quantum information

29.05.2015 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>