For the past four months, the Phoenix Mars Lander has been roaming the Red Planet collecting soil samples in search of signs of water and life. But the seasons are changing on Mars and time is running out for the UA-built craft, which will soon be crippled by the planet’s freezing winter temperatures.

At this likely end to the mission, scientists are examining the last pieces of data from the lander. On Friday, the principal investigators of the exploration of Mars gathered at the UA’s Phoenix Science and Operations Center to discuss their recent discoveries on the popular National Public Radio program “”Science Friday.””

Ira Flatow, the host of “”Science Friday,”” asked university scientists and principal investigators Peter Smith and Alfred McEwen about the Phoenix mission and what is known about the fourth planet from the Sun. Joining the discussion were William Hartmann, the senior scientist at the Planetary Science Institute and Steven Squyres, the principal investigator of the Mars Exploration Rover Mission.

The live broadcast, sponsored by Arizona Public Media, was recorded in front of an audience of about 200 curious followers of the exploration of Mars, including President Robert Shelton.

“”This is huge publicity for the University of Arizona,”” Shelton said. “”It is a tremendous opportunity for Tucson and the state of Arizona. The entire state should be proud of this Mars mission.””

Shelton called the Phoenix mission “”the most exciting mission to Mars ever in the history of human kind.””

During the one-hour broadcast, the panelists answered questions from the audience and discussed many aspects of Mars, including the planet’s craters, polar ice caps, atmosphere and soil.

While more is understood about our neighboring planet with each mission, one discovery has proved troubling for Phoenix scientists: the soil is nothing like they expected.

Phoenix’s instruments have been unable to analyze the soil because of its clumpy composition. Over the course of the mission, scientists have struggled to fill the lander’s Thermal and Evolved Gas Analyzer with samples of soil and ice.

The TEGA instrument is a crucial part of Phoenix’s mission. The TEGA is used to “”bake”” soil samples in its ovens and then “”sniff”” any gases that they might release in order to analyze the soil’s contents.

Although scientists have tried to improvise solutions, they have found themselves in sticky situations: samples cling to a screen above the TEGA instrument, and Phoenix lacks the ability to reliably pass samples into the TEGA.

“”We’re still trying to learn a better way of doing this,”” Smith said. “”Martian materials have been a very difficult set of challenges.””

Smith reported that there was no way of anticipating the “”devilish”” composition of the soil from the information the team had while building Phoenix. Smith joked about the tricky and unexpected nature of planetary exploration.

“”We read the travel brochure,”” Smith said. “”But it didn’t say anything about this. It didn’t get down into the details that would help us design our instruments properly.””

Although Phoenix was unable to answer many questions scientists had about Martian soil, it has been able to provide a tremendous amount of weather information. From Phoenix’s position in the polar planes, it beams daily weather updates back to Earth and has given scientists a first-time look into the onset of the frigid Martian winter.

Another aspect of the mission, the High Resolution Imaging Experiment (HiRISE), will continue to aid NASA scientists long after the Phoenix Lander is gone.

The UA-created HiRISE provides detailed images of the surface from the Mars Reconnaissance Orbiter, allowing scientists to map it. HiRISE is currently guiding another NASA craft across the treacherous rocky surface of the planet. The Mars Exploration Rover Opportunity, which landed in 2004, is exploring Victoria Crater and will move to a larger crater soon.

Steve Squyres, the Opportunity mission’s principal investigator, commented on the importance of HiRISE in steering the rover.

“”We wouldn’t dare try this if we didn’t have the HiRISE data,”” Squyres said. “”What HiRISE does is provide us with a spectacular road map that tells us how to get from here to where we’re going. With the HiRISE data as a guide, we can do better than 100 meters in a day.””

Opportunity has lasted far past its projected lifespan of 90 days and will explore Mars as long as it is able, Squyres said. He also said that a future NASA rover mission, called the Mars Science Laboratory, is planned to launch in 2009.

“”This rover is bigger and more powerful,”” Squyers said. “”It’s got a very powerful scientific payload that can detect trace abundances of organic molecules, if they’re there.””

In terms of future exploration, scientists hope to be able to bring back carefully-selected rocks so that they will be able to analyze them in controlled environments.

In response to one of Flatow’s questions at the discussion asking Smith what he would do with the Mars mission if he had a blank check, Smith, who believes much of the Martian history can be read through the ice layers, said he would wish to further analyze the composition of the icy soil by drilling into the planet’s surface.