NASA Searches for Clues To Alien Life!

By Tim Gaynor
Reuters
4-4-05


CUATRO CIENEGAS, Mexico (Reuters) - With cobalt waters harboring eerie, coral-like formations, this archipelago of lakes in Mexico's searing Chihuahuan desert has always had an other-worldly appearance.

Now top researchers at the U.S. National Aeronautics and Space Administration say the calcified clumps of primitive bacteria lurking in its pools could provide important clues in their search for extraterrestrial life.

The network of 170 cactus-ringed lagoons around the town of Cuatro Cienegas have intrigued evolutionary biologists for decades because their fish, snail and turtle species rival the Galapagos Islands in their uniqueness.

Scientists from NASA's Astrobiology Institute have begun studying the lakes' ancient formations called stromatolites -- rock structures formed by layers of algae that trap silt. Conditions within the stromatolites are similar to those that prevailed on Earth for more than 2 billion years before the dinosaurs evolved.

Studying their organisms could help NASA identify the unique atmospheric conditions created by primitive life on planets orbiting nearby stars and help settle the question of whether we are alone in the universe.

"They may be our best example of what to look for on other planets," said Brad Bebout, a researcher at the NASA Ames Research Center, as he prepared to harvest methane belched out by the organisms in a shallow blue-green pool.

"Most of the time that life has been on Earth, this is what it looked like, not like the plants and animals that you see around you now," he added.

MICROBIAL LIFE

The stromatolites and other colonies of single-celled organisms were marooned in the pools when the sea retreated more than 100 million years ago, leaving a tantalizing glimpse of the life forms that thrived on early Earth and created an atmosphere based on oxygen.

NASA's hunch is that planets around nearby stars could be populated by similar colonies of primitive bacteria, which served as the basis from which complex, multicellular plants and animals that inhabit the Earth later evolved.

Aided by two scuba divers, researchers have taken a range of gas readings, cell and chemical samples from the clusters of bacteria, which look like clumps of coral dropped into the parched desert.

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