Green Valley High School student teacher Missie Trader, center, and Tara Weatherholt, right, explore Cima Cave during a field trip Wednesday to the lava tube, 25 miles southeast of Baker, Calif., as part of the "Spaceward Bound" program. Photos by Samantha Clemens. Scientists and teachers stand Wednesday at the opening of a lava tube created by molten rock in the Mojave Desert southeast of Baker. Apple Valley, Calif., teachers Frank Cleary and Meg Deppe watch a camera-equipped rover being operated remotely by teachers inside a building Wednesday at the Desert Studies Center at Zzyzx, Calif. Desert Research Institute microbiologist Henry Sun discusses the similarities between Mars and the Mojave Desert while standing Wednesday in the Soda Springs dry lake bed at Zzyzx, Calif.

CIMA CRATER, Calif.

With a headlamp strapped to her pink baseball cap, Missie Trader climbed down a ladder into the darkness of a lava cave and took a step toward understanding what life might be like on Mars.

As she walked into the cave, or "lava tube," as geologists call it, bright light from Wednesday afternoon's sun poured through three holes in its ceiling.

That's where, thousands of years ago, molten rock broke through weak spots on the surface and flowed onto the desert floor. In so doing, it left an empty tube much like water flows from a garden hose and leaves the hose empty when the faucet is shut off.

Inside Cima Cave, 25 miles southeast of Baker, the tube is longer than a boxcar and roughly 15 feet beneath the surface.

"It's amazing. It's definitely something I wouldn't find on my own," said Trader, a 31-year-old graduate student at the University of Nevada, Las Vegas.

The Chicago transplant is working on her master's degree in education. She is a student teacher at Green Valley High School and one of several teachers from Clark County schools who participated last week in the Mojave Desert expedition of "Spaceward Bound," a partnership among Nevada's Desert Research Institute, NASA Ames Research Center and San Jose State University.

The program is aimed at sowing the seeds for future generations to explore Mars.

On this outing, Trader was joined by another UNLV education major and future teacher, Tara Weatherholt, who described the cave experience in one word: "Awesome."

"Our main goal is to show students what it's like to be a real scientist," she said before heading to the back end of the cave.

That's where Penny Boston, an astrobiologist from New Mexico Tech was preparing to show her and Trader how to extract bacterial microbes from the cave's volcanic rock walls.

In all, 40 scientists and 40 teachers from across the nation collaborated in the weeklong, hands-on workshop. The expedition was geared toward teaching teachers about the similarities of volcanic regions on Mars and the Mojave Desert so they go back to their classrooms and inspire their students about exploring Mars, the moon and the space frontier.

For many types of microbes, or single-celled plants, sunlight along with moisture and nutrients are essential ingredients for their survival.

But the bacteria that's glued to the rock inside Cima Cave can survive in darkness. That's because they get energy to live through a chemical process by oxidizing minerals instead of relying on the energy of sunlight to process food, water and carbon dioxide for growth.

Boston said the knowledge gained on how to detect and measure bacteria in cave rocks on Earth will be important in looking for signs of life on Mars.

"On modern Mars, if there is any hope of life, it's in the subsurface," she said.

The atmosphere on Mars is so thin that it affords no protection from the sun's intense ultraviolet radiation. As such, the chances of even the most hardy life forms surviving are remote unless they are in caves or buried deep within Martian soils.

At Zzyzx, about 15 miles southwest of Baker on the salt-crusted Soda Springs dry lake bed, Desert Research Institute microbiologist Henry Sun was studying the other end of the microbial spectrum in a harsh environment where temperatures range from 10 degrees to 120 degrees and only three inches of rain per year fall on the soil that holds microorganisms.

On Wednesday, Sun held a gypsum rock that had been cracked open. He pointed to a green layer.

"This is a microbial community. If you put this under the microscope you will see the green organisms," he explained. "These are single-celled, photosynthetic bacteria, one of the most primitive life forms on Earth. Essentially these are microscopic plants."

Like this stretch of the Mojave Desert, Mars is a desert, which makes the Mojave an excellent place for scientists to rehearse their search for life on Mars.

"The ecology of life on Mars, if there is life on Mars, should be very similar," Sun said. "So we would be expecting to see these kinds of life forms on Mars. ... Microbes living in rocks (are) a very likely candidate in the search for life on Mars."

The Martian search-for-life effort, Sun noted, had its genesis in 1976 when NASA's Viking Mars mission put a pair of landers on the planet.

"The mission was successful, but the results were inconclusive. We are still debating today what those results mean," he said.

The Mars Exploration Rovers project that was launched in 2003 has been relaying priceless data about the planet to scientists on Earth thanks to the mobile robots, Spirit and Opportunity. They landed in January 2004, and their extended missions continue today.

At the Desert Studies Center in Zzyzx, teachers learned how to remotely drive small-scale rovers.

One teacher, A. Carey Sperling of Bridger Middle School in North Las Vegas, said he would like to construct a rover as part of the aerospace and aviation curriculum. His students already take Astronaut Training 101.

"I know a number of my students want to be astronauts, scientists and engineers. So if we're going to be going to Mars, they're the ones who are going to be doing it," he said.

"They really need to know how to do all this stuff," Sperling said, adding that he had "an opportunity to work with the robots. They didn't look that difficult to build."

He said the expedition made him feel "like a hard-core scientist." He also discussed with his colleagues the possibility of arranging a student field trip to the center.

"We can replicate a lot of the science that they're doing with the kids, because a lot of it is not as difficult as it sounds," he said.

"It's very easy for them to take a soil sample and learn how to wash the dirt and look at the water under a microscope and see microbes," Sperling said. "That's something the kids can do and understand and just kind of relate. That's what scientists are going to be doing when they go to Mars to search for life forms or even possibly on the moon, not that we really expect to find much there."

Christie LeBeau, a Bridger Middle School earth science teacher, said educators and students cannot afford to miss the opportunities at Zzyzx, a two-hour drive from the Las Vegas Valley.

"It's definitely interesting to see how this desert, which is right in Las Vegas' backyard, will be the analog for Mars. ... Every Clark County teacher should be bringing their students here for a field trip," LeBeau said. "This is important to put our kids on that pathway."