Microbes Offer Clues to Chance of Life on Mars

Microbes dubbed “SLiME” that are found deep within the earth may provide clues about the potential for life on Mars, U.S. scientists at the Pacific Northwest Laboratory said Thursday.

They said they found the microbes in ground water deep below the surface at the Department of Energy’s Hanford site in Washington state. Unlike most other life forms, the microbes do not depend on photosynthesis, or the use of light to produce essential complex organic materials.

The scientists called it a subsurface lithoautotrophic microbial ecosystem--SLiME. They found that the microbes might be able to live on rocks alone as long as they are rich in basalt and iron.

The microbes appear to be hydrogen-eating bacteria that get their chemical energy from an interaction between ground water and the iron in basalt, a rock on Earth and Mars, the researchers said.

In theory, the basalt finding could indicate that microbes could exist in the Martian subsurface if, as some scientists now believe, not all the Martian ground water is frozen.