ASU Mars camera celebrates a decade's discoveries


February 29, 2012

Ten years ago, on Feb. 19, 2002, the Thermal Emission Imaging System (THEMIS), a multi-band camera on NASA's Mars Odyssey orbiter, began scientific operations at the Red Planet. Since then the camera has circled Mars nearly 45,000 times and taken more than half a million images at infrared and visible wavelengths.

"THEMIS has proven itself a workhorse," says Philip Christensen, the camera's designer and principal investigator. Christensen is a Regents' Professor in the School of Earth and Space Exploration, part of Arizona State University's College of Liberal Arts and Sciences. "It's especially gratifying to me to see the range of discoveries that have been made using this instrument." V00816002 THEMIS' first science image Download Full Image

Highlights of science results by THEMIS over the past 10 years include:

• confirming that hematite is widespread on Meridiani Planum, which led NASA to send one of its Mars Exploration Rovers there

discovering CO2 gas jets at the south polar ice cap in spring

discovering chloride salt deposits across the planet

• making the best global image map of Mars ever done

• identifying safe landing sites for NASA's Mars Phoenix spacecraft by finding the locations with the fewest hazardous boulders

monitoring dust activity in the Martian atmosphere

• discovering that a large impact crater, Aram Chaos, once contained a lake

• discovering that Mars has more water-carved channels than previously thought

discovering dacite on Mars, a more evolved form of volcanic lava not previously known on the Red Planet

THEMIS combines a 5-wavelength visual imaging system with a 9-wavelength infrared imaging system. By comparing daytime and nighttime infrared images of an given area, scientists can determine many of the physical properties of the rocks and soils on the ground.

Mars Odyssey has a two-hour orbit that is nearly “Sun-synchronous,” meaning that Odyssey passes over the same part of Mars at roughly the same local time each day. In September 2008 its orbit was shifted toward an earlier time of day, which enhanced THEMIS' mineralogical detection capability.

Says Christensen, "Both Odyssey and THEMIS are in excellent health and we look forward to years more science with them."

NASA launched the Mars Odyssey spacecraft April 7, 2001, and it arrived at Mars Oct. 24, 2001. On arrival the spacecraft spent several months in a technique called aerobraking, which involved dipping into the Martian atmosphere to adjust its orbit. In February 2002, science operations began.

The Mars Odyssey project is managed by the Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems in Denver built the spacecraft, and JPL and Lockheed Martin collaborate on operating it.

Robert Burnham

Science writer, School of Earth and Space Exploration

480-458-8207

Article on training adaptive teams earns professors, postdoc national recognition


February 29, 2012

Training teams to be more adaptive in new situations can prevent disasters and help recover from crises much more efficiently and quickly. In 2009, US Airways Flight 1549 went down after striking a large flock of birds during its initial climb. With Capt. Chesley “Sully” Sullenberger, the pilot, and his crew’s ability to adapt to the circumstance, the plane was successfully ditched in the Hudson River. One thing we learned from the crew’s emergency response is the importance in training adaptive teams to be resilient and flexible during crises and rare circumstances.  

In their award-winning article, “Training Adaptive Teams,” Nancy Cooke, professor of cognitive science and engineering at ASU’s College of Technology and Innovation, Jamie Gorman, psychology postdoc, and Polemnia Amazeen, associate professor of psychology at ASU’s College of Liberal Arts and Sciences, compared training methods for team coordination in an unmanned aerial vehicle (UAV) ground control simulator. The article received the Jerome H. Ely Human Factors Article Award at the Human Factors and Ergonomics Society annual meeting in Las Vegas. Download Full Image

The experiment outlined in the article compared three training approaches and measured their effectiveness in terms of training adaptive teams. Cross-training, an established method in which team members are trained on the tasks and responsibilities of fellow team members, relies heavily on shared knowledge. Perturbation training is a new method in which team interactions are constrained to provide new coordination experiences during task acquisition. Both approaches and the more traditional procedural approach were assigned to 26 teams. The teams flew nine simulated UAV missions, and three were critical tests of the team’s ability to adapt to novel situations. The researchers measured team performance, response time to novel events and shared knowledge.

The results showed that perturbation-trained teams significantly outperformed teams in two out of three critical test missions, an outcome that was somewhat surprising according to Cooke.

“The prevalence of a cross-training approach in real-world applications leads a lot of people to think that it is the most effective way to train a highly adaptive team,” said Cooke. “However, perturbation training, which is done by throwing roadblocks into the process like system or communications breakdowns, teaches teams to be flexible and know what to do in very rare circumstances. That kind of resiliency is what leads to more adaptive teams.”

Perturbation training is amenable to simulation-based training, where trainers can manipulate distractions, unique scenarios and unforeseen breakdowns. Such interruptions provide interaction experiences that teams can transfer to real-world solutions.

“Adaptation is all about being able to bend and adjust in accordance with change,” said Cooke. “Responding to unknown circumstances and perturbations in a manipulated environment pushes teams to decide, plan, think and act under conditions they have never experienced. That’s where the real-world application comes in; perturbation training allows teams to be highly adaptable in any situation that comes their way.”