[This story summarizes a report from the San Francisco Chronicle of March 17, 1998, written by David Perlman; and a posting at NASA's Space Sciences Laboratory web site, http://science.msfc.nasa.gov/newhome/headlines/ast12mar98_1.htm. CNI News thanks Stig Agermose for bringing this information to our attention.]
American and Russian scientists, seeking clues to possible life on Jupiter's moon Europa, have found an astonishing array of living organisms in layers of Antarctic ice hundreds of thousands of years old.
The Galileo spacecraft has returned evidence of water ice and slush covering much of the surface of Europa. To assess whether that slush or the possible liquid water underneath might hold life, researchers have been exploring deep Antarctic ice cores more than 100,000 years old.
The ice cores were drilled more than a mile deep by Russian scientists at their Vostok research station at Antarctica. In some of the corings, scientists have detected a variety of bacteria, algae, fungus spores and diatoms. The frozen organisms may have been carried to Earth inside ancient comets, the scientists believe.
U.S. astronomer Richard Hoover of NASA's Marshall Space Flight Center and his research partner Sabit S. Abyzov of the Russian Institute of Microbiology in Moscow are working at NASA's Jet Propulsion Laboratory in Pasadena, California to analyze samples from the ice cores.
"We've seen some really bizarre things that we've never seen before," Hoover said. "We're exploring a new world. Until we get a lot more experience, we're going to see brand new things all the time."
Researchers have already given some of the strange microbes nicknames, such as Mickey Mouse, Klingon, porpoise, sphere, and leftover turkey.
"There are all sorts of microorganisms in the ice. Some are readily recognizable as cyanobacteria, bacteria, fungi, spores, pollen grains, and diatoms, but some are not recognizable as anything we've ever seen before," Hoover said.
Also working with the team at JPL is microbiologist Kenneth Nealson, a member of JPL's new astrobiology division. NASA has announced that astrobiology is a new discipline aimed at studying the evolution of planets and life both within and beyond the solar system.
The scientists are using JPL's extremely sensitive Environmental Scanning Electron Microscope (ESEM) to study the new microbes and also to determine if any of the material in the ice may have come from space. "There are some dust particles with unusual spectra," Hoover said, "which may be cosmic dust particles."
Of great importance is the fact that Abyzov and his Russian colleagues have been able to revive and culture a variety of organisms that have apparently been locked in the ice for over 100,000 years.
"What is clearly going on is that when microorganisms freeze, they shut down and go into this anabiotic state," Hoover explained. The anabiotic state is a form of suspended animation. Hypothetically, organisms in an anabiotic state could travel through space on a comet for thousands or even millions of years before landing on a hospitable world like the earth, where they might revive and flourish.
When Galileo first sent back photographic evidence of water ice on Europa last year, scientists were quick to speculate on possible life there.
"The combination of interior heat, liquid water and infall of organic material from comets and meteorites means that Europa has the key ingredients for life," declared Brown University geologist James Head, a member of the Galileo team, when the latest images from Europa were released in early March, 1998.
Hoover goes even further, noting that some of the clearest images of Europa's icy regions show colored material. Some spots on the slush, he said, seem to be reddish, some bear a green tint and some are golden brown.
"I get excited in Antarctica when I see golden brown ice," Hoover said, "because to me golden brown means diatoms, and that's what shows up in the ice cores from Vostok, too. It's a safe guess that colors like that could come from biology anywhere."
The drilling at Vostok station reached 3,610 meters deep, where the ice is some 400,000 years old, and then was deliberately stopped. The reason for stopping is that 100 meters further down is a huge, recently discovered warm-water lake that may be a completely uncontaminated reservoir of extremely ancient life.
NASA scientists and Russian colleagues are jointly planning to design a completely sterile robotic life-detecting instrument that can reach the lake and emerge with uncontaminated water samples. The device has already been named a "Cryobot," and teams from both nations will be meeting in San Diego this summer to discuss strategies for building it.
"That lake is one of the most precious resources on Earth," Hoover said. "It's the best analogue of Europa we have, and when we hunt for life down there, we'll have to be as careful about contamination as we would be when we bring back samples from the planets."
NASA has already begun discussing ways to send a similar robotic probe to Europa to search for life there.
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