Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists Shape First Global Topographic Map of Saturn’s Moon Titan

17.05.2013
Scientists have created the first global topographic map of Saturn’s moon Titan, giving researchers a valuable tool for learning more about one of the most Earthlike and interesting worlds in the solar system.

Titan is Saturn’s largest moon – at 1,600 miles (2,574 kilometers) across it’s bigger than planet Mercury – and is the second-largest in the solar system. Scientists care about Titan because it’s the only moon in the solar system known to have clouds, surface liquids and a mysterious, thick atmosphere.

The cold atmosphere is mostly nitrogen, like Earth’s, but methane on Titan acts the way water vapor does on Earth, forming clouds and falling as rain and carving the surface with rivers. Organic chemicals, derived from methane, are present in Titan’s atmosphere, lakes and rivers and may offer clues about the origins of life.

“Titan has so much interesting activity – like flowing liquids and moving sand dunes – but to understand these processes it’s useful to know how the terrain slopes,” says Ralph Lorenz, of the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., who led the map-design team. “It’s especially helpful to those studying hydrology and modeling Titan’s climate and weather, who need to know whether there is high ground or low ground driving their models.”

Titan’s thick haze scatters light in ways that make it very hard for remote cameras to “see” landscape shapes and shadows, the usual approach to measuring topography on planetary bodies. Virtually all the data we have on Titan comes from NASA’s Saturn-orbiting Cassini spacecraft, which has flown past the moon nearly 100 times over the past decade. On many of those flybys, Cassini has used a radar imager, which can peer through the haze, and the radar data can be used to estimate the surface height.

"With this new topographic map, one of the most fascinating and dynamic worlds in our solar system now pops out in 3-D," says Steve Wall, the deputy lead of Cassini's radar team, based at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "On Earth, rivers, volcanoes, and even weather are closely related to heights of surfaces – we're now eager to see what we can learn from them on Titan."

There are challenges, however. “Cassini isn’t orbiting Titan,” Lorenz says. “We have only imaged about half of Titan’s surface, and multiple ‘looks’ or special observations are needed to estimate the surface heights. If you divided Titan into 1-degree by 1-degree [latitude and longitude] squares, only 11 percent of those squares have topography data in them.”

Lorenz’s team used a mathematical process called splining – effectively using smooth curved surfaces to “join” the areas between grids of existing data. “You can take a spot where there is no data, look how close it is to the nearest data, and use various approaches of averaging and estimating to calculate your best guess,” he says. “If you pick a point, and all the nearby points are high altitude, you’d need a special reason for thinking that point would be lower. We’re mathematically papering over the gaps in our coverage.”

The estimations fit with current knowledge of the moon – that its polar regions are “lower” than areas around the equator, for example – but connecting those points allows scientists to add new layers to their studies of Titan’s surface, especially those modeling how and where Titan’s rivers flow, and the seasonal distribution of its methane rainfall. “The movement of sands and the flow of liquids are influenced by slopes, and mountains can trigger cloud formation and therefore rainfall. This global product now gives modelers a convenient description of this key factor in Titan’s dynamic climate system,” Lorenz says.

The most recent data used to compile the map is from 2012; Lorenz says it could be worth revising when the Cassini mission ends in 2017, when more data will have accumulated, filling some of the gaps in present coverage. “We felt we couldn’t wait and should release an interim product,” he says. “The community has been hoping to get this for a while. I think it will stimulate a lot of interesting work.”

The map, as well as a paper on the project (“A Global Topography Map of Titan”), appear in the journal Icarus and are available online at: http://www.sciencedirect.com/science/article/pii/S0019103513001620.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and ASI, the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the US and several European countries.

The Applied Physics Laboratory, a not-for-profit division of The Johns Hopkins University, meets critical national challenges through the innovative application of science and technology. For more information, visit www.jhuapl.edu.

Michael Buckley | New
Further information:
http://www.jhuapl.edu
http://www.jhuapl.edu/newscenter/pressreleases/2013/130515.asp

More articles from Physics and Astronomy:

nachricht Magnetic nano-imaging on a table top
20.04.2018 | Georg-August-Universität Göttingen

nachricht New record on squeezing light to one atom: Atomic Lego guides light below one nanometer
20.04.2018 | ICFO-The Institute of Photonic Sciences

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: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

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

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>