Source : Shanghai Daily
SCIENTISTS at the University of Wisconsin-Madison are helping search for evidence of alien life not by looking into outer space, but by studying some rocks on Earth.
Some of the rocks are up to 3.5 billion years old. Scientists are looking for information to understand how life might have arisen elsewhere in the universe and guide the search for life on Mars one day.
"There's a story always hidden in rocks," said geoscientist Clark Johnson, lead investigator for the Wisconsin Astrobiology Research Consortium. "... It's up to (geologists) to be clever enough to find the tools that we need to interrogate those rocks to find what story they preserve."
The project is financed through NASA, which provided a US$7 million, five-year grant that started in January. It was the group's second five- year, US$7 million grant.
They've found new details of microbial life that dates back 2 billion to 3 billion years, before the planet's atmosphere contained oxygen. They've found that microbes then relied more on iron than sunlight for energy.
Eventually their work will be used to interpret data brought back from Mars by the six-wheel spacecraft Curiosity, which landed in August on a two-year mission to determine whether the environment was ever favorable for microbial life.
"It may be that planets spent a long time in a microbial life condition and then only rarely evolved to advanced multicellular complex life," according to Johnson.
