November 12, 1999: Volume 47, Number 10

Ballston Lake Ecology May Help in Search for ET Life

Microbial life from the depths of Ballston Lake may shed some light on the kinds of life forms that NASA scientists should look for on Mars and elsewhere.

Paul Gremillion, assistant professor of civil engineering, traveled to Kennedy Space Center in Florida recently to speak to scientists on "Understanding Biological Artifacts of Extreme Environments."

He related the highly unusual water chemistry and microbial ecology of Ballston Lake with some of the ongoing work at NASA, including the search for evidence of microbial activity on Mars and exploration of the perennially ice-covered oceans of Europa, a moon of Jupiter.

He presented this talk to a group of scientists and engineers working in ecological programs at the Merritt Island space facility and on the Mars and lunar colonization program.

Gremillion, who specializes in chemical systems found in lakes, was invited by a former colleague who directs life sciences support for shuttle missions.

NASA recently lost a Mars probe – the Climate Orbiter — that was to aid in the investigation of life on Mars. Its sister ship – the Polar Lander – is to land on Dec. 3. Scientists are designing a probe to penetrate the ice and sample the water on Europa, Gremillion said. The next mission to Europa is planned for launch in November 2003.

"I wanted to tie in the unusual environment of Ballston Lake with some of the things that they study," Gremillion said. "Nobody there studies lakes, but they do a lot of biological and ecological work on odd systems, like looking for evidence of what microbial evidence on Mars might look like. If life exists or existed, it stands to reason that it may be astonishingly different than on Earth."

For example, scientists might expect microbial life on Mars to be photosynthetic but not use oxygen, much like some of the microbes Gremillion, his students and colleagues have found in Ballston Lake.

NASA scientists are investigating microbes found in extreme environments on earth, like those found near hydrothermal vents on the ocean floor, Gremillion said. "These life forms are not the typical base of the food chain, the chlorophyll-bearing algae," he said.

On the surface, Ballston Lake is like any other. But the south end is deep and narrow; there is not adequate wave action to circulate the water column, as happens in most lakes. About 18 meters down, you'll find the chemocline – a chemical stratification of oxygen-depleted water that has high levels of iron and low levels of sulfate. In other words, the environment at and below the chemocline is extreme, Gremillion said. Yet, there are life forms – microscopic bacteria — that thrive there.

Gremillion is one of a number of faculty and students doing research under the Ballston Lake Initiative, a multidisciplinary research project examining the natural processes and effects of human impact on the lake. Project director in John Garver, director of environmental studies.

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