About 40 years ago, a team of New Zealand researchers drove past the place where Diane M. McKnight and her graduate students now live in bright yellow pup tents. The tire tracks are still there.
Change, Ms. McKnight says, comes very slowly around F6, one of four field camps in the Dry Valleys just west of McMurdo Station, the main U.S. research base in Antarctica. And that is very helpful for scientists modeling basic ecological and biological processes that might be found on distant planets, says Ms. McKnight, a professor of civil, environmental, and architectural engineering at the University of Colorado at Boulder.
About 98 percent of the Antarctic land mass is buried in ice or snow. The Dry Valleys, along the coast near the Ross Sea, are exceptional not only because the continent itself is visible but also because the surrounding hills make the area comparatively warm. Ms. McKnight and her students are among a couple of dozen members of research teams who spend weeks living here during the Antarctic summer season. For researchers, the arid and nearly lifeless Dry Valleys serve as an analogue for Mars, she says.
Fittingly, the area looks like a moonscape, an expanse of brown volcanic soil dotted with stones and boulders. In the distance rise gently sloped snow-capped hills.
Water running off the hills follows a path through the middle of the F6 tent site and into Lake Fryxell, and it’s that meltwater that is one of the site’s main attractions. Bright orange boxes sit along the stream, connected to tubes that measure the flow of water and the microbes carried in it.
The lack of anything else—grass, trees, animals—is crucial, says Emily Bernzott, a graduate student from Pennsylvania State University who is working on Ms. McKnight’s team. “In some ways it’s more of a simplified system, and in some ways it’s more complicated,” Ms. Bernzott explains. The system is simpler because there’s no plant or animal life, but more complicated because the exchanges of materials between water and soil don’t follow the rules seen almost everywhere else in the world.
Ms. McKnight says some of the most fascinating interactions in the Dry Valleys involve the cyanobacteria, diatoms, and other bacteria around the lake and streams. They form algae mats that sit freeze-dried during the winter, then revive months or even years later, in a matter of just 10 or 15 minutes, when exposed to water, she says. “That just-add-water approach to looking for life on Mars is a good way to go,” she says.
A few miles to the west, Joseph S. Levy has similar thoughts as he watches the streams around his own tent site fill Lake Hoare.
Mr. Levy is a postdoctoral research associate at Oregon State University who specializes in both polar and planetary studies. As he motions toward the hilltops, he describes the value of the system as a lab for showing how water and nutrients move through a cold, dry ecosystem, feed organisms that live in the soil, and then deposit the results of the biological processes into the lakes below.
Like Ms. Bernzott, he puts great value on the lack of complicating interactions. “It’s a simple system to understand,” Mr. Levy says, and that simplicity can help inspire “insights into how more complicated systems work at temperate latitudes.”
The lessons in hydrology, he says, have clear—and hopeful—implications for the possibility of life on other planets, including Mars, where conditions are extremely cold and extremely dry, but with enough atmospheric humidity to form liquid water.
“Every day, Antarctica starts looking more like Mars to me, and Mars starts looking more like Antarctica,” Mr. Levy says, standing before a stark panorama of barren brown earth and bright blue sky. “So it keeps me optimistic.”
