Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Odyssey thermal data reveals a changing Mars

06.06.2003


The first overview analysis of a year’s worth of high-resolution infrared data gathered by the Thermal Emission Imaging System (THEMIS) on NASA’s Mars Odyssey spacecraft is opening Mars to a new kind of detailed geological analysis and revealing a dynamic planet that has experienced dramatic environmental change.

The report by THEMIS’s science team will appear in an upcoming issue of Science and will be released on June 5 in the magazine’s online preview, Science Express.

"THEMIS is creating a set of data that is going to revolutionize our mapping of the planet and our idea of the planet’s geology," said lead author and THEMIS Principal Investigator Philip Christensen, Korrick Professor of Geological Sciences at Arizona State University. "It will keep Mars scientists busy for the next 20 years trying to understand the processes that have produced this landscape."



THEMIS is providing planetary geologists with detailed temperature and infrared radiation images of the martian surface. The images reveal geological details that were impossible to detect even with the high-resolution Mars Orbital Camera on NASA’s Mars Global Surveyor and that have 300 times higher resolution than MGS’s Thermal Emission Spectrometer. Among the significant findings noted in the report is the detection of layers in the martian surface that indicate major changes in past environmental conditions.

"With a visible light camera, I can take a picture of a lava flow, but even with the highest resolution cameras that we have today the smallest thing we can see is the size of a bus and in order to do geology I need to have more detail," said Christensen.

"The camera on Mars Global Surveyor takes exquisite images that show layers, but it doesn’t tell me anything about composition – is it a layer of boulders with a layer of sand on top? I have no way of knowing. With the THEMIS temperature data, I can actually get an idea because the layers vary – and each layer has remarkably different physical properties."

Daytime and nighttime temperature data can allow scientists to distinguish between solid rock and a variety of loose materials, from boulders to sand and dust. As any beach-goer knows, fine-grained sand heats up more rapidly at the surface than solid stone (which transmits more heat inward) but it also cools off more rapidly at night, when solid materials retain heat.

"We have seen layers, each with dramatically different physical properties, in places like Terra Meridiani," Christensen said. "Why do the physical properties in the different layers change? They change because the environment in which those rocks were deposited changed.

"It’s very difficult to say exactly what happened in any particular place, but what we’ve found is that in many places on Mars it hasn’t just been the same old thing happening for year after year for billions of years. These data have been so remarkable and so different from all of our previous experience that it has taken time to sift through the images and figure out what we’re seeing."

Among the details that have stood out so far are kilometer-wide stretches of bare bedrock that Christensen notes were unexpected, given the Mars’ known dustiness. Large areas of exposed rock indicate that strong environmental forces are currently at work, "scouring" from the surface any past sediment as well as any new material that might be falling from the atmosphere.

Also unexpected is the finding that accumulations of loose rock are common on martian hillsides, indicating recent processes of weathering continuing to affect the planet. " If those rocks had been made a billion years ago, they’d be covered with dust," Christensen pointed out. "This shows a dynamic Mars – it’s an active place."

However, despite Odyssey’s past findings of significant martian ice deposits, there are also indications that, in many places on the planet, water may not be one of the active causes behind the observed geological features.

Analyzing the spectra from the ten different bands of infrared light the instrument can detect, the THEMIS team has begun to identify specific mineral deposits, including a significant layer of the mineral olivine near the bottom of a four-and-a-half kilometer deep canyon known as Ganges Chasma. Olivine, Christensen notes, is significant because it decomposes rapidly in the presence of water.

"This gives us an interesting perspective of water on Mars," he said. "There can’t have been much water – ever -- in this place. If there was groundwater present when it was deep within the surface, the olivine would have disappeared. And since the canyon has opened up, if there had ever been water at the surface it would be gone too. This is a very dry place, because it’s been exposed for hundreds of millions of years. We know that some places on Mars have water, but here we see that some really don’t."

Overall, Christensen notes that the emerging diversity and complexity of the planet point to the likelihood of future surprises and keep enlarging the possibilities for discovery on Mars.

"With Odyssey, we are looking at Mars in its entirety, in context. It’s remarkable how much this has already changed our view of the complexity and richness of the planet. We discovered that it has a really dynamic geologic history. It has far more ice and water than we thought -- we’re seeing snow and gullies, layers – and there are also processes involving volcanoes, impact craters and wind. It’s a fascinating place."

In addition to Christensen, the authors on the paper include Joshua L. Bandfield, James F. Bell, Noel Gorelick, Victoria E. Hamilton, Anton Ivanov, Bruce M. Jakosky, Hugh H. Kieffer, Melissa D. Lane, Michael C. Malin, Timothy McConnochie, Alfred S. McEwen, Harry Y. McSween, Greg L. Mehall, Jeffery E. Moersch, Kenneth H Nealson, James W. Rice, Mark I. Richardson, Steven W. Ruff, Michael D. Smith, Timothy N. Titus, and Michael B Wyatt.



###
The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 2001 Mars Odyssey mission for NASA’s Office of Space Science in Washington. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA’s Johnson Space Center, Houston, operate the science instruments. Additional science partners are located at the Russian Aviation and Space Agency and at Los Alamos National Laboratories, New Mexico. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL. Additional information about the 2001 Mars Odyssey is available on the Internet at: http://mars.jpl.nasa.gov/odyssey/

James Hathaway | EurekAlert!
Further information:
http://www.asu.edu/asunews/
http://mars.jpl.nasa.gov/odyssey/

More articles from Physics and Astronomy:

nachricht NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center

nachricht Pluto's hydrocarbon haze keeps dwarf planet colder than expected
16.11.2017 | University of California - Santa Cruz

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: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>