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Post by Surfed By on Jul 27, 2004 16:41:04 GMT -5
Mars Express has detected an area of high water vapour over a region of the Red Planet called Arabia Terra. The finding seems to confirm earlier data from the Mars Odyssey spacecraft that the region was "wet".
Vapour was also found to be enhanced in the Tharsis region of Mars. High water vapour areas seem to match bright patches, when Mars is seen from space.
"Increased water vapour correlates with higher albedo on the surface," said mission scientist Dr Dmitri Titov.
The Arabia Terra finding agrees with a map of water-equivalent hydrogen on the Red Planet compiled by Nasa's Mars Odyssey probe. The map is thought to be an indicator of water reservoirs lurking beneath the surface.
Arabia Terra was found to be one of the most significant "reservoirs" of subsurface hydrogen.
This water may mostly be stored as water-ice, although scientists say there could still be stores of liquid water on the planet.
The Marsis radar instrument aboard Mars Express is designed to look for liquid water and ice beneath the Martian surface, but its deployment has been delayed until later in the year.
The Tharsis results were presented at the 35th Committee on Scientific Research (Cospar) scientific assembly here in Paris, France.
The data comes from the probe's Planetary Fourier Spectrometer science instrument, which has also confirmed the presence of methane in Mars' atmosphere.
Tharsis is the equatorial region on Mars that contains some of the planet's great volcanoes, such as Olympus Mons.
Arabia Terra is a 5,000km-wide swathe of cratered terrain to the east and north of Tharsis.
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Post by Surfed By on Jul 27, 2004 16:43:48 GMT -5
Mars scientists in Europe and the United States have detected tantalizing signs of methane gas in the Martian atmosphere, and cannot yet explain why it's there.
Methane is commonly exuded by living organisms and fermentation. It can also belch to the surface during volcanic eruptions, and can be carried by comets that at times have crashed into Earth and other planets.
The amounts of atmospheric methane detected by instruments aboard the European Space Agency's Mars Express spacecraft now orbiting the planet are extremely small -- barely more than 10 parts per billion, but the find is already creating a major buzz among Mars researchers.
Steven Squyres, now famed as the leader of the team guiding the Mars rovers Spirit and Opportunity on their epochal tour of the Martian surface, would not talk to a reporter about the European find this week after a talk to a major astrobiology conference at NASA's Ames Research Center in Mountain View.
But Bernard Foing, an organic chemist on the Mars Express team who also attended the astrobiology meeting, cited three possible major sources for the methane.
First, it could be emerging from a Martian volcano that is unexpectedly erupting right now, even though little or no volcanic activity has been observed on Mars from high-resolution ground-based telescopes on Earth or from orbiters circling the Red Planet.
Second, the gas could have carried into the planet's atmosphere by a grazing comet or asteroid, even by one that hit the surface very recently.
And third -- probably the least likely but certainly the most dramatic of all -- it could be emerging from beneath the Martian surface where some kind of living organisms -- bacteria, perhaps -- might be surviving and nourishing themselves by chewing on rocks containing chemicals that serve as a source of energy.
One thing is certain, however: Wherever the methane comes from, it must be either of relatively recent origin or be continuously replenished, because the gas lasts only a few hundred years or so before it oxidizes into water and carbon dioxide.
"We cannot know more until we find out more," Foing said in an interview, "and that will take many more observations both to confirm that the gas is there and to locate its source on the planet."
The European Space Agency first disclosed the methane find Monday after Vittorio Formasino, the lead scientist for the spacecraft's Planetary Fourier Spectrometer, confirmed that the instrument had indeed detected methane's chemical signature.
"The first thing to understand is how exactly the methane is distributed in the Martian atmosphere," Formasino said. "Based on our experience on Earth, the methane production could be linked to volcanic or hydrothermal activity (sub-surface hot springs) on Mars."
But Formasino added cautiously: "If we have to exclude the volcanic hypothesis, we could still consider the possibility of life."
The first tentative detection of methane in the Martian atmosphere was announced last year by Michael Mumma, a physicist at NASA's Goddard Space Flight Center near Washington, D.C. He found the telltale evidence in observations by ground-based telescopes at Cerro Pachon in Chile and the giant Keck II instrument on Mauna Kea in Hawaii.
Vladimir Krasnopolsky of the Catholic University of America in Washington, D.C., reported Monday that he and his colleagues had also found evidence of Martian methane using the Canada-France-Hawaii telescope atop Mauna Kea.
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Post by Surfed By on Jul 27, 2004 16:46:52 GMT -5
Methane has been discovered on Mars, raising the possibility of past or present life on the Red Planet.
The gas was detected recently using the Planetary Fourier Spectrometer (PFS) on the European Space Agency orbiter Mars Express.
Vittorio Formisano, principal investigator of PFS, said the finding could either be evidence of life or of volcanic activity.
Many more observations and studies were required to identify the source of the methane, he added.
"Eventually we shall perhaps be able to identify the source of methane," he said.
"The source is going to be a rather big issue. The source could be either simply volcanic activity, or life of biological origin.
"I am not stating that there is life now. There is no conclusion yet."
The scientist said methane could only exist for a few hundred years in the Martian atmosphere.
This meant there could still be life or volcanic activity now on the Red Planet.
Formisano added: "In my opinion it is most likely of volcanic origin, but I need many more observations.
"For the moment, we can only say there is evidence of methane, and we have the possibility of accumulating more data and eventually finding the source."
Colin Pillinger, chief scientist of missing Mars probe Beagle 2, said the discovery could be evidence of "past life or even current life".
He said he believed the gas was unlikely to be the production of volcanic activity alone.
Scientists on Mars Express have previously detected frozen water at the Martian south pole, which they said confirmed the possibility that Mars once harboured life.
Last week, Nasa announced that its Mars rover Opportunity had discovered what was once a salty sea on the Red Planet.
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Post by Mike Hawkins on Aug 3, 2004 21:28:00 GMT -5
[glow=red,2,300]LIFE ON MARS? - YES!!!![/glow] "All factors necessary to constitute a habitat for life as we know it exist on current-day Mars," explained Gilbert Levin, executive officer for science at Spherix Incorporated of Beltsville, Maryland.
Levin made his remarks here Monday at the International Symposium on Optical Science and Technology, the 49th annual meeting of Society of Photo-Optical Instrumentation Engineers (SPIE).
Provocative find:
Levin has a long-standing interest in time-weathered Mars and the promise of life today on that distant and dusty world.
NASAs 1976 Viking mission to Mars was geared-up to look for possible martian life. And it was Levins Labeled Release experiment that made a provocative find: The presence of a highly reactive agent in the surface material of Mars.
Levin concluded in 1997 that this activity was triggered by living microorganisms lurking in the martian soil -- a judgment he admits has not been generally accepted by the scientific community.
Now roll forward to 2004. Consider the findings of Spirit and Opportunity, the golf-cart sized robots wheeling over Mars at Gusev Crater and Meridiani Planum.
"Those rovers have been absolutely sensational, pouring out thousands of images. Those images have lots of information in them. And Ive tried to deduce something in there relative to life...and I think I found a lot," Levin told SPACE.com.
Squeezed out of the soil
In perusing rover imagery, Levin reports there is clear evidence for liquid water existing under Martian environmental conditions. "The images should be reviewed against the background of surface temperatures as varying from below to above freezing reported by both Spirit and Opportunity," he explained.
Levin points to the potential for mud puddles on Mars, showing an image of clearly disturbed martian soil after rover airbags bounced across Mars surface. Possible standing water and sinkholes can also be seen in rover imagery, according to his analysis. In some pictures, the often-discussed "blueberries, " tiny spheres of material, disappear as if submerged underneath mud-like surroundings, he added.
Then there are tracks left by the machines as they roll across the martian terrain. Self-taken shots by the robots show what Levin said appears to be water squeezed out of the soil which then freezes into a whitish residue left in embedded tread marks.
Similarly, Levin added, are images taken by Opportunity of the results from an operation of the robots Rock Abrasion Tool, or RAT. The center of that particular RAT hole is largely white, possibly indicating the formation of frost since the hole was drilled, he noted.
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Post by Mike Hawkins on Aug 3, 2004 21:30:38 GMT -5
[glow=red,2,300]Organisms there now?[/glow] "The evidence presented strongly indicates the presence of liquid water or moisture at the Mars Exploration Rover sites," Levin reported at the SPIE meeting. "Mars today could support many forms of terrestrial microbial life."
Other scientists are cautious to point out that the presence of water does not guarantee life. Rather, it means one crucial ingredient exists.
There is clear evidence for frost or ice on Mars, the former Viking experimenter stated. At some point of the day -- when temperatures climb above freezing -- theres going to be moisture..."and thats enough to support microorganisms," he said.
None of the many new findings about Mars revealed by Spirit and Opportunity, Levin concluded, conflict with, or render untenable, his long-held belief that the Viking Labeled Release experiment in 1976 detected living microorganisms in the soil of Mars.
"I contend that today you could take a great many Earth microorganisms, put them on Mars, and theyd grow," Levin said. "And I think there are organisms there now. They may have come from Earth. They may have originated on Mars. They may have come from a third place that populated both Mars and Earth."
Rocks can be kicked up from one planet by an asteroid impact, drift through space for eons, then land on the other. Other studies have shown that these rocks could potentially transport life, in a dormant phase, from one planet to the other.
Levin said that he thinks the "greatest speculation" would be to say there can be no life on Mars.
Moon used as Earth bio-shield
If indeed Mars is rife with life, care should be taken in hauling back to Earth specimens of rock and surface materials from the red planet. NASA (news - web sites) has indicated that, next decade, robotic craft could be dispatched to gather and return to Earth select samples of Mars for detailed laboratory study.
Could those bits of Mars, perhaps laden with martian microbes, act as dangerous cargo?
As a precaution, Levin advocates a kind of bio-shield strategy for Earth -- but using the Moon.
The new NASA vision to reestablish a human presence on the Moon is good timing, Levin said. "Bring samples of Mars not to Earth but to the Moon," he said. "There we would have built a scientific laboratory in which scientists could examine the samples and determine whether or not there is a hazard."
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