Not every graduate student can say he sent his dissertation project 422 million miles as a means to earn a doctor of philosophy degree. But Peter H. Smith can. 

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The world peered over his shoulder as Smith led the NASA-funded Phoenix Mars Mission last summer from The University of Arizona campus, where he has been a senior research scientist at the Lunar and Planetary Laboratory since 1978. He earned a master's degree in 1977 from the UA's College of Optical Sciences.

The Phoenix's laboratory was open for all to see through the mission's Web site, which posted images as soon as they were beamed to Earth from Mars. Researchers and the public saw them at the same time.

The announcement on July 30, 2008, that the Phoenix team had discovered water ice on the Red Planet set into motion the activities leading to Smith's receiving a Ph.D. in optical sciences from the UA on May 16. His paper for the prestigious journal "Science" on that significant discovery – "Water at the Phoenix Landing Site" – served as his dissertation.

Smith has a long history as a planetary scientist and especially with capturing images of Mars. His camera on the Mars Pathfinder mission in 1997 sent back stunning images of the equatorial region of the planet. He designed that camera to record all the nuances of the planet so often thought of as merely one color – red.

Smith built cameras for the next two planned missions to Mars, but one crashed on the surface at landing and the following mission was canceled. But from the ashes of those missions arose "Phoenix," which put the UA, Tucson and all of Arizona on the map as a hotbed of planetary exploration.

Phoenix's goal was to determine the habitability of the northern polar region of Mars. The instruments aboard the tiny craft – seated on a platform about the size of a breakfast table – analyzed soil samples by sniffing and tasting to determine if that place on the planet could ever have supported life. Discovering that there once had been liquid water was a key finding for the science team.

"We found the most habitable zone on Mars of the six landed missions" that NASA has sent there, Smith said. In addition to the water ice, Phoenix's findings included calcium carbonate, a clear sign on Earth of the presence of liquid water; perchlorates, both oxidizers and potential energy sources, were a "huge surprise" that Smith said were unexpected and are found only in hyperarid places on Earth. The team's observations of the Martian polar weather – dust devils, ground fog and snow – have provided rich data for scientists to develop new models of the planet's weather patterns.

Smith will continue his planetary research at UA as the Thomas R. Brown Distinguished Chair of Integrated Science.

Given the twists and turns that have made Mars research so challenging, Smith quips, "Mars is the irony-rich planet." The lessons and discoveries of Phoenix will add to the body of knowledge about the planet and provide incentive for further exploration.

Phoenix Lander Worked Like a Champion

The Phoenix Mars Lander surpassed its original three-month mission, lasting five months after landing in the Martian northern plains on May 25, 2008.

Phoenix returned more than 30,000 images. It took 29,799 images that provided panoramic views of the landing site and weather information with its Surface Stereo Imager. It took 2,322 images with its Robotic Arm Camera. Phoenix even took views down to the atomic level with the first atomic force microscope ever used beyond Earth.

Phoenix's Robotic Arm was critical to the mission. It executed 53 dig sequences and dug in 12 different areas, scooping soil at one place more than 7 inches deep.

The arm successfully delivered soil into six of eight tiny ovens in the TEGA, or the Thermal and Evolved-Gas Analyzer, which heated soil samples to 1,800 degrees Fahrenheit. The arm delivered seven samples to the optical microscope instrument and four samples to the lander's wet chemistry lab.

The lander was to have lasted 90 Martian solar days, or sols. Remarkably, it performed science during 149 sols of its total 152-sol lifetime. Temperatures ranged from a high of minus 3.28 degrees Fahrenheit to a low of minus 143.86 degrees Fahrenheit.

More about what Phoenix accomplished can be found the on the Phoenix Mission Web site.

Phoenix was last seen in an image taken by the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment, or HiRISE, camera, operated by Alfred McEwen's team at the UA, on Dec. 21, 2008. More pictures aren't possible until sun again shines on the northern polar plains.

Mission managers deem chances that the lander can be revived when Martian spring arrives at northern Mars in October 2009 as "very unlikely."

Nevertheless, they'll ask the Mars Odyssey orbiter to hail Phoenix just to be sure.

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