EXTRATERRESTRIAL:
Spirit, Stardust zero in on off-earth life
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NASA engineers enjoyed a double portion of jubilation Sunday and Monday as the robot Spirit began sending pictures from Mars and the Stardust probe sent a snapshot of the Wild-2 comet and collected a thimbleful of dust from the comet's tail, which is to be returned to Earth for analysis in 2006. While both technological marvels promise to expand human knowledge of the universe, the quest that underlies both expeditions is the quest for life beyond earth.
As an article in Monday's edition of Space.Com says, "As NASA prepares to set twin robots loose on the Martian surface and makes plans to send another in 2007, the agency's long term goal is clear: Determine whether the red planet does or ever did harbor life."
The Stardust probe is part of the same quest for life. Proponents of the panspermia theory suggest that comets could be a transmission belt for organic material or even living microorganisms from planet to planet. Many articles supporting that theory can be found in Brigham Klyce's Cosmic Ancestry website. Stardust could confirm this theory if it finds organic material in the comet's tail.
Hope for finding evidence of Mars life is bolstered by the discovery of bacteria living in extreme environments on earth in conditions similar to Mars. A recent issue of the journal Astrobiology says a bacteria discovered under the Siberian permafrost grows and reproduces in conditions as chilly as 14 degrees Fahrenheit (-10 degrees Celsius). Scientists figure that at certain times in the history of Mars, the tilting of its pole to a more oblique angle would have caused the north polar cap to warm enough to for such organisms to thrive.
Some scientists are already convinced that Mars harbors life based on evidence sent back by the first Mars landers and photos of the Mars surface taken by the Mars orbiter. An article in Cosmic Ancestry says, "The evidence sent back from Mars by two Viking Landers in 1976 and 1977 was not clear cut. In fact, NASA's first press release about the Viking tests announced that the results were positive. The 'Labelled Release' (LR) experiments had given positive results. But after lengthy discussions in which Carl Sagan participated, NASA reversed its position, mainly because another experiment detected no organics in the soil. Yet Gilbert V. Levin, the principal designer of the LR experiment, still believes the tests pointed to life on Mars. When the same two experiments were run on soil from Antarctica, the same conflicting results were obtained (LR - positive; organics - negative.) Soil from Antarctica definitely contains life. The test for organics was negative because it is far less sensitive than the LR experiment. The same problem could have caused the organics test on Mars to give a false negative."
Some scientists say changing spots on Mars photographed by the Mars Orbiter camera show growing vegetation, like a mould. "'We cannot find anything else to explain it,' said evolutionary biologist Tibor Gánti, one of three Hungarian scientists issuing the report. The team studied 60,000 photographs taken by the Mars Global Surveyor Probe before concluding that the organisms lived by photosynthesis." NASA asserts, however, that the spots are created by frost melting, uncovering patches of darker sand.
UFO enthusiasts need no convincing that Mars harbors life, perhaps event the ruins of an ancient civilization, such as the famous face and pyramids on Mars, which NASA insists are natural formations. George Filer in a recent edition of Filer's Files reports, "An engineer Norman M. Bryden has sent me some extraordinary images of possible extraterrestrial artifacts on Mars. Many of these images show structures that appear as vegetation with root like structures spreading out from them like banyan trees. We know that water exists on Mars and that the seeds of life can spread throughout the universe. There is no satisfactory natural explanation for these structures, unless we are looking at some sort of growing moulds or vegetation."
While we must wait until January 2006 for analysis of Stardust's comet dust, the probe's onboard analyzer sent back tantalizing results early in its mission. In April, 2001, Stardust's German-made analyzer caught a few particles of interstellar dust that turned out to be "complex organic compounds, and not the expected minerals," according to an article in Cosmic Ancestry. "This is the conclusion of the team from Max-Planck Institute, Garching, that manages the mass-spectrometer, CIDA, on NASA's Stardust spacecraft. 'The first in-situ chemical analysis of interstellar dust particles produces a puzzling result: These cosmic particles consist mostly of 3-dimensionally cross-linked organic macro-molecules, so-called polymeric-heterocyclic-aromates. They rather resemble tar-like substances than minerals.'
"It is the size of these molecular fragments with nuclear masses of up to 2000... which surprised us as much as the seemingly absence of any mineral constituents.... Only organic molecules can reach those sizes," the article said.
Among all the dramatic information coming out of these two probes, the most meaningful would be final proof that Earth is not an oasis of life in a sterile universe, but part of an ever-changing cosmic network of life permeating every corner of the universe.
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