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Latest Mars exobiology news:

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07.29.2018Liquid water ponds under Mars ice had already been theoretically found in 1987.
07.25.2018Mars Express detects liquid water pond under Mars' South Pole ice layer.
01.20.2018Curiosity rover spots weird tiny structures on Mars.
11.09.2017Determining how long microorganisms could live on Mars
06.02.2017Curiosity rover science team finds Mars Gale crater lake simultaneously had different conditions favorable for different types of microbes.
05.31.2017Lighter-toned bedrock indicates Mars had liquid water much longer than previously believed.
10.01.2016Discovery in vivo in 2014 of organics on Mars with the SAM intrument of the Curiosity rover.
12.13.2009Scientists say the methane found on Mars is not brought to the planet by meteor strikes.
09.25.2009Scientists see more water ice than expected in fresh craters On Mars.
07.06.2009NASA Phoenix scientific results publications.
07.02.2009Landforms indicate recent warm weather.
11.22.2008Mars: Short-lived bursts of methane percolating to the surface detected.
11.22.2008Vast buried glaciers detected.
05.25.2008Phoenix lands on Mars.
05.23.2008Found evidence of formerly habitable niche on Mars surface is now in academic scientific journal.
12.06.2006MGS provides proof of liquid water flow on Mars again.
11.30.2006News from the famous Tagish Lake meteorite.
12.13.2004Mars exoplanetology and exobiology at LPI/NASA seminar.
08.15.2004The detected/not detected ammonia on Mars found again, at ESA's web site.
07.27.2004No, ammonia not detected on Mars.
07.19.2004Ammonia detected, one more evidence for present life on Mars.
07.19.2004Biological hotspots on Mars? wonders scientist.
03.27.2004Was unofficial now official: methane, a tell-tale sign of life, has been found on Mars.
09.01.2004NASA's Spirit measures ground level temperatures.
07.01.2004NASA's Spirit image shows what looks like muddy soil under the surface dust.
12.10.2002And again probable liquid water on Mars.
09.26.2002Russian study says an Earth bacteria is of Martian origin.
09.04.2002Life in near Martian conditions simulation.
05.30.2002Many scientists discover evidence of water in MGS pictures now.
05.29.2002Gilbert L. Levin: the king has clothes.
05.25.2002Another major Mars water announcement coming soon.
04.14.2002Amino acids artificially created in simulated interstellar conditions.
12.14.2001New evidence of vast amount of water 3 feet below surface in warm regions.
12.06.2001NASA realizes that the Martian climate is not that stable.
12.05.2001Latest new evidence of past life on Mars.

Liquid water ponds under Mars ice had already been theoretically found in 1987:

The report of the detection of liquid water beneath the surface of the Martian south pole ice - see previous news below - actually validates research published by PSI Senior Scientist Stephen Clifford back in 1987, as a paper published in the June 25 issue of Science. The paper demonstrated the theoretical presence of liquid water buried about one mile beneath the layers of ice os the MArtian polar caps.

Clifford said:

"The work I did 30 years ago was basically a theoretical exercise that considered what we then knew about the extensive network of subglacial lakes and channels that exist at the base of the Antarctic and Greenland ice sheets and examined its potential relevance to the Martian polar caps."

"It is certainly gratifying that the MARSIS radar team has now found evidence that demonstrates that this early theoretical work has some connection to reality."

Mars Express detects liquid water pond under Mars' South Pole ice layer:

The European Space Agency (ESA) used radar data from their Mars Express probe, radar signals bounced through underground layers of ice, to identify a pond of liquid water buried below the surface of the ice at the South Pole of Mars. Radar profiles for 29 orbits over the 200 x 200 km study region were used. The pond is about 1.5 km below the ice layer and 20 km wide.

The presence of liquid water below the polar ice layers of Mars has long been suspected, as there are such ponds below the ice layer of the South Pole on Earth, such as Lake Vostok. It is well-known that the melting point of water decreases under the pressure of overlying ice. Moreover, the presence of salts on Mars could further reduce the melting point of water and keep the water liquid even at below-freezing temperatures.

Until now evidence from the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument, MARSIS, the first radar sounder ever to orbit another planet, remained inconclusive. It needed the persistence of scientists working with this subsurface-probing instrument to develop new techniques in order to collect as much high-resolution data as possible to confirm their conclusion.

Analyzing the properties of the reflected radar signals and considering the composition of the layered deposits and expected temperature profile below the surface, the scientists interpret the bright feature as an interface between the ice and a stable body of liquid water, which could be laden with salty, saturated sediments. For MARSIS to be able to detect such a patch of water, it would need to be at least several tens of centimeters thick.

Roberto Orosei, principal investigator of the MARSIS experiment and lead author of the paper published in the journal Science, said:

"This subsurface anomaly on Mars has radar properties matching water or water-rich sediments,"

"This is just one small study area; it is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered."

Andrea Cicchetti, MARSIS operations manager and a co-author on the new paper, added:

"We'd seen hints of interesting subsurface features for years but we couldn't reproduce the result from orbit to orbit, because the sampling rates and resolution of our data was previously too low.".

"We had to come up with a new operating mode to bypass some onboard processing and trigger a higher sampling rate and thus improve the resolution of the footprint of our dataset: now we see things that simply were not possible before."

Dmitri Titov, ESA's Mars Express project scientist, satated:

"The long duration of Mars Express, and the exhausting effort made by the radar team to overcome many analytical challenges, enabled this much-awaited result, demonstrating that the mission and its payload still have a great science potential".

"This thrilling discovery is a highlight for planetary science and will contribute to our understanding of the evolution of Mars, the history of water on our neighbor planet and its habitability."

The research paper can be read online at the ESA website at:

http://sci.esa.int/mars-express/60519-orosei-et-al-2018

Curiosity rover spots weird tiny structures on Mars:

Many popular science websites announced from Jaunary 6, 2018 and on, that the Curiosity rover spotted weird tiny structures on the surface of Mars. For example the above image, captured on January 2, 2018, with Curiosity's Mars Hand Lens Imager (MAHLI). Using an onboard focusing process, the camera software created this product by merging two to eight images previously taken by MAHLI, which is located on the turret at the end of the rover's robotic arm.

Researcher Barry DiGregorio, a fellow for the Buckingham Centre for Astrobiology in the United Kingdom, browsing the images, found it and speculated these may be fossils. DiGregorio is the author of the nonfiction books "Mars: The Living Planet" and "The Microbes of Mars." He said:

"They look remarkably similar to Ordovician trace fossils I have studied and photographed here on Earth. If not trace fossils, what other geological explanations will NASA come up with?"

Leonard David, Space.com columnist, asked Ashwin Vasavada, of the NASA Jet Propulsion Laboratory in Pasadena, what he thought of this. Vasavada reported that the are very small, probably on the order of a millimeter or two in width, with the longest stretching to roughly 5 millimeters.

The feature were first spotted in black and white imagery, and the Curiosity science team found then compelling enough to drive Curiosity back to examine them further, making use of MAHLI, Vasavada said.

Curiosity team member Christopher Edwards, a planetary geologist at Northern Arizona University in Flagstaff, also made note of the plan to wheel Curiosity back to study the dark-toned "stick-like" features.

"This site was so interesting that we backtracked to get to where the rover was parked for this plan," Edwards wrote in a Jan. 3 mission update. "In the work space in front of the rover, we have some very peculiar targets that warranted some additional interrogation."

Vasavada said that they do not rule fossils aout but certainly won't jump to that as their first interpretation.

The features appear angular in multiple dimensions; which could mean that they are related to crystals in the rock, perhaps "crystal molds" that are also found here on Earth, Vasavada said. "Crystals in rock that are dissolved away leave crystal molds."

Pascal Lee, planetary scientist at the Mars Institute and SETI (Search for Extraterrestrial Intelligence) Institute in Mountain View, California. said : "it's hard to tell what the wiggly sticks are, and a strictly mineral origin is, of course, the most plausible."

But on first view of the features, Lee said that as a field geologist, "the immediate thought that came to my mind is bioturbation" - the process through which organisms living in sediments can disturb the structure of these sediments.

Astrobiologist Dirk Schulze-Makuch, a professor at Technical University of Berlin in Germany and adjunct professor at Arizona State University and Washington State University said it could probably be concretions, formations of precipitated minerals.

Curiosity's Chemistry and Camera (ChemCam) and its Alpha Particle X-Ray Spectrometer (APXS) are now inspecting the features for clues as to their nature.

Curiosity rover science team finds Mars Gale crater lake simultaneously had different conditions favorable for different types of microbes:

The NASA Jet Propulsion Laboratory (JPL) at Pasadena, CA, reported on June 2, 2017, that a comprehensive look at findings from the first 3.5 years of NASA's Curiosity rover mission on Mars revealed that the long-lasting lake in Gale crater provided stable environmental conditions on ancient Mars differing significantly from one part of the lake to another.

Previous work had revealed the presence of this lake more than three billion years ago in Mars' Gale Crater. The new study defines the chemical conditions that existed in the lake and, using Curiosity's powerful payload, it determined that the lake was stratified in different conditions favorable for different types of microbes, conditions that existed simultaneously.

Joel Hurowitz of Stony Brook University, Stony Brook, New York, is the lead author of the paper of the findings published in the June 2, 2017, edition of the journal Science. He said that there were "were very different, co-existing environments in the same lake."

"This type of oxidant stratification is a common feature of lakes on Earth, and now we've found it on Mars. The diversity of environments in this Martian lake would have provided multiple opportunities for different types of microbes to survive, including those that thrive in oxidant-rich conditions, those that thrive in oxidant-poor conditions, and those that inhabit the interface between those settings," he said.

First, the differences in the physical, chemical and mineral characteristics of several sites on lower Mount Sharp were a puzzle to the rover science team. Some rocks showed thicker layering with a larger proportion of an iron mineral called hematite, while other rocks showed very fine layers and more of an iron mineral called magnetite. Comparing these properties suggested very distinctive environments of deposition.

Researchers considered whether these differences could have resulted from environmental conditions fluctuating over time or differing from place to place.

"We could tell something was going on," Hurowitz said. "What was causing iron minerals to be one flavor in one part of the lake and another flavor in another part of the lake? We had an 'Aha!' moment when we realized that the mineral information and the bedding-thickness information mapped perfectly onto each other in a way you would expect from a stratified lake with a chemical boundary between shallow water and deeper water."

The paper by Hurowitz and 22 co-authors also documents fluctuations in the climate of ancient Mars. One change happened between the time crater-floor rocks were deposited and the time the rocks that now make up the base of Mount Sharp were deposited. These more recent rocks are exposed at "Pahrump Hills" and elsewhere.

While the lake was present in Gale, climate conditions changed from colder and drier to warmer and wetter. Such short-term fluctuations in climate took place within a longer-term climate evolution from the ancient warmer and wetter conditions that supported lakes, to today's arid Mars.

The science paper is here: http://science.sciencemag.org/content/356/6341/eaah6849

Lighter-toned bedrock indicates Mars had liquid water much longer than previously believed:

Lighter-toned bedrock that surrounds fractures and comprises high concentrations of silica, called "halos", were found in Gale crater on Mars. This, scientists say, indicates that the planet had liquid water much longer than previously believed.

The new finding is reported in a paper published this week in Geophysical Research Letters, a journal of the American Geophysical Union, published on May 31, 2017.:

The abstract reads:

Diagenetic silica enrichment in fracture-associated halos that crosscut lacustrine and unconformably overlying aeolian sedimentary bedrock is observed on the lower north slope of Aeolis Mons in Gale crater, Mars. The diagenetic silica enrichment is colocated with detrital silica enrichment observed in the lacustrine bedrock yet extends into a considerably younger, unconformably draping aeolian sandstone, implying that diagenetic silica enrichment postdates the detrital silica enrichment. A causal connection between the detrital and diagenetic silica enrichment implies that water was present in the subsurface of Gale crater long after deposition of the lacustrine sediments and that it mobilized detrital amorphous silica and precipitated it along fractures in the overlying bedrock. Although absolute timing is uncertain, the observed diagenesis likely represents some of the most recent groundwater activity in Gale crater and suggests that the timescale of potential habitability extended considerably beyond the time that the lacustrine sediments of Aeolis Mons were deposited.

Jens Frydenvang, scientist at Los Alamos National Laboratory and the University of Copenhagen and lead author of the paper, said that "the concentration of silica is very high at the centerlines of these 'halos'. What we're seeing is that silica appears to have migrated between very old sedimentary bedrock and into younger overlying rocks. The goal of NASA's Curiosity rover mission has been to find out if Mars was ever habitable, and it has been very successful in showing that Gale crater once held a lake with water that we would even have been able to drink, but we still don't know how long this habitable environment endured."

"What this finding tells us is that, even when the lake eventually evaporated, substantial amounts of groundwater were present for much longer than we previously thought - thus further expanding the window for when life might have existed on Mars."

The "halos" were analyzed by rover Curiosity's science payload, including the laser-shooting Chemistry and Camera (ChemCam) instrument, developed at Los Alamos National Laboratory in conjunction with the French space agency.

The elevated silica in halos was found over approximately 20 to 30 meters in elevation near a rock-layer of ancient lake sediments that had a high silica content.

"This tells us that the silica found in halos in younger rocks close by was likely remobilized from the old sedimentary rocks by water flowing through the fractures," said Frydenvang.

Specifically, some of the rocks containing the halos were deposited by wind, likely as dunes. Such dunes would only exist after the lake had dried up. The presence of halos in rocks formed long after the lake dried out indicates that groundwater was still flowing within the rocks more recently than previously known.

See: "Diagenetic silica enrichment and late-stage groundwater activity in Gale crater, Mars", 30 May 2017, http://onlinelibrary.wiley.com/doi/10.1002/2017GL073323/abstract;jsessionid=0E2D050409242DFF2DB2A63B1FDF8505.f02t01

Experts say life could survive on Mars:

It's been years that I and other say a few things about the possibility of life on Mars. I have been saying that whereas water freezes at 0°C, it is not the case when water is salty and there is no reason to believe Mars water is not salty. I have been saying that whereas many popular websites claim the temperature on Mars is minus 60°C, it is not a constant temperature and temperature charts for Mars show places and times when the temperatures rises above 0°C, up to +15°C. I have been saying that this means that Mars cannot be hostile to life. I have been saying that there are places on Earth more hostile to life where microbial life thrives anyway.

Now on June 7, 2010, researchers at McGill's department of natural resources, the National Research Council of Canada, the University of Toronto and the SETI Institute have discovered that methane-eating bacteria survive in a highly unique spring located on Axel Heiberg Island in Canada's extreme North. Dr. Lyle Whyte, Toronto University microbiologist, explains that the Lost Hammer spring supports microbial life, that the spring is similar to possible past or present springs on Mars, and that therefore they too could support life.

The team says that the subzero water is so salty that it does not freeze despite the cold, and it has no consumable oxygen in it. There are, however, big bubbles of methane that come to the surface, which had provoked the researchers' curiosity as to whether the gas was being produced geologically or biologically and whether anything could survive in this extreme hypersaline subzero environment.

They say that they were surprised that they did not find methanogenic bacteria that produce methane at Lost Hammer. But they did find other very unique anaerobic organisms, organisms that survive by essentially eating methane and probably breathing sulfate instead of oxygen.

It is known for decades that there is at least frozen water on Mars, photos taken by the Mars Orbiter show the formation of new gullies, very likely formed by running water, and it was discovered more recently that methane is produced on Mars.

Dr. Lyle Whyte said: "If you have a situation where you have very cold salty water, it could potentially support a microbial community, even in that extreme harsh environment."

"There are places on Mars where the temperature reaches relatively warm -10 to 0 degrees and perhaps even above 0 degrees C," Whyte said, "and on Axel Heiberg it gets down to -50, easy. The Lost Hammer spring is the most extreme subzero and salty environment we've found. This site also provides a model of how a methane seep could form in a frozen world like Mars, providing a potential mechanism for the recently discovered Martian methane plumes."

Scientists say methane found on Mars isn't brought by meteor strikes:

A paper by scientists at Imperial College of London in Earth and Planetary Science Letters argues that the methane detected in Mars' atmosphere does not come from meteors but from geologic, chemical or biological processes, since meteoritic material subjected to high temperatures did not release enough methane to account for the amount believed to be released on Mars.

The scientists heated meteorite fragments to 1,000C, quantifying the gases produced by measuring how much they absorbed an infrared laser, and then calculated, based on estimates of how many meteorites impact Mars annually, how much methane would be released. They found it was not enough: only 10kg of methane is produced from meteors each year, in contrast to the 100-300 tons that must be produced to keep the atmospheric concentration at its current levels.

Methane was first detected on Mars in 2004. This gas has a limited lifetime in the Martian atmosphere before being degraded by the sunlight, therefore some process must be pumping hundreds of tons of it into the Martian atmosphere annually to keep it at the detected levels.

See: www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V61-4XJP5XV-3&_user=10&_coverDate=11%2F15%2F2009&_alid=1129478045&_rdoc=4&_fmt=high&_orig=search&_cdi=5801&_sort=r&_docanchor=&view=c&_ct=16&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=05e154f67653c567da565dc261f68e68

Scientists see more water ice than expected in fresh craters on Mars:

Several instruments on the Mars Reconnaissance Orbiter in quick succession detected highly pure bright ice exposed in new craters, ranging from 1.5 feet to 8 feet deep at five different Martian sites. The bright ice material fades in months because of sublimation and obscuration by settling dust.

Shane Byrne of the University of Arizona, member of the High Resolution Imaging Science Experiment, or HiRISE; which runs the high-resolution camera on NASA's Mars Reconnaissance Orbiter, said:

"We knew there was ice below the surface at high latitudes of Mars, but we find that it extends far closer to the equator than you would think, based on Mars' climate today. The other surprising discovery is that ice exposed at the bottom of these meteorite impact craters is so pure. The thinking before was that ice accumulates below the surface between soil grains, so there would be a 50-50 mix of dirt and ice. We were able to figure out, given how long it took that ice to fade from view, that the mixture is about one percent dirt and 99 percent ice."

In August 2008, the orbiter's Context camera team examined their images for any dark spots or other changes that weren't visible in earlier images of the same area. Meteorites usually leave dark marks when they crash into dust-covered Mars terrain.

The HiRISE team, which bases its operations at the UA Lunar and Planetary Laboratory, followed up in September 2008 by taking high-resolution images of the dark spots.

Byrne said: "We saw something very unusual when we followed up on the first of these impact craters, and that was this bright blue material poking up from the bottom of the crater. It looked a lot like water ice. And sure enough, when we started monitoring this material, it faded away like you'd expect water ice to fade, because water ice is unstable on Mars' surface and turns directly into water vapor in the atmosphere."

A few days later that September the orbiter's "CRISM" team used their Compact Reconnaissance Imaging Spectrometer for Mars and got the spectral signature of water ice exposed in one of the impact craters, confirming it was really water ice.

Byrne said: "All of this had to happen very quickly because 200 days after we first saw the ice, it was gone, it was the color of dirt. If we had taken HiRISE images just a few months later, we wouldn't have noticed anything unusual. This discovery would have just passed us by."

He said that to find highly pure ice far closer to the equator because of random meteor impacts was unexpected. How far water ice extends toward the equator depends largely on how much water has been available in the Martian atmosphere in the recent past, Byrne said: "The ice is a relic of a more humid climate not very long ago, perhaps just several thousand years ago."

Byrne and 17 co-authors are reporting the findings in the September 25 edition of the journal Science.

Landforms indicate recent warm weather:

Dr. Matthew Balme, from The Open University, U-K., led new research on the high resolution images of Mars from NASA's HiRISE (High Resolution Imaging science Experiment) which is onboard the Mars Reconnaissance Orbiter (MRO). By studying detailed images of equatorial landforms, his team found landscapes formed by melting of ice-rich soils.

His research, funded by the UK's Science and Technology Facilities Council (STFC) and published in Earth and Planetary Science Letters indicates that the Martian surface experienced "freeze thaw" cycles as recently as 2 million years ago, and that Mars was locked in permafrost conditions for billions of years as had been previously thought but had a significantly warmer weather in its recent past.

The high resolution images he studied were previously interpreted to be the result of volcanic processes, but they show a variety of interesting landforms, features that are instead caused by the expansion and contraction of ice, and by thawing of ice-rich ground. These landforms observed are in an outflow channel thought to have been active as recently as 2 million to 8 million years ago. Since the landforms exist within, and cut across, the pre-existing features of the channel, this suggests that they too were created within this timeframe.

The pictures show polygonally patterned surfaces, branched channels, blocky debris and mound/cone structures, features that are all similar to landforms on Earth typical of areas where permafrost terrain is melting. It demonstrates not only that there was ice near the Martian equator in the last few million years, but also that the ice melted to form liquid water and then refroze, and this probably happened for many cycles.

Given that liquid water seems to be essential for life, these kinds of environments could be a great place to look for evidence of past or dormant life on Mars.

Short-lived burst of methane fumes percolating to the surface detected:

Planetary scientists at NASA's Goddard Flight Center say they detected hotspots of methane gas emission, as extremely localized plumes whose concentration fades quickly in time. An atmosphere-wide distribution that's stable in time would indicate a balance between geological sources and destruction by sunlight but such localized sources might suggest much more active sources: NASA team leader, Michael Mumma, suggested that subterranean bacteria could be producing these short lived bursts.

Vast buried glaciers detected:

Scientific American is reporting that data from the Mars Reconnaissance Orbiter point to vast glaciers buried beneath thin layers of crustal debris. Data from the surface-penetrating radar on MRO revealed that two well-known mid-latitude features are composed of solid water ice. One is about three times the size of the City of Los Angeles.

News from the famous Tagish Lake meteorite:

William Jeffs
Johnson Space Center, Houston
281-483-5111

11.30.06
RELEASE: J06-103

NASA Scientists Find Primordial Organic Matter in Meteorite

NASA researchers at Johnson Space Center, Houston have found organic materials that formed in the most distant reaches of the early Solar System preserved in a unique meteorite. The study was performed on the Tagish Lake carbonaceous chondrite, a rare type of meteorite that is rich in organic (carbon-bearing) compounds.

Organic matter in meteorites is a subject of intense interest because this material formed at the dawn of the Solar System and may have seeded the early Earth with the building blocks of life. The Tagish Lake meteorite is especially valuable for this work because much of it was collected immediately after its fall over Canada in 2000 and has been maintained in a frozen state, minimizing terrestrial contamination. The collection and curation of the meteorite samples preserved its pristine state.

In a paper published in the Dec. 1 issue of the journal Science, the team, headed by NASA space scientist Keiko Nakamura-Messenger, reports that the Tagish Lake meteorite contains numerous submicrometer hollow organic globules.

"Similar objects have been reported from several meteorites since the 60's. Some scientists believed these were space organisms, but others thought they were just terrestrial contamination," said Nakamura-Messenger. The same bubble-like organic globules appeared in this freshest meteorite ever received from space. "But in the past, there was no way to determine for sure where these organic globules came from because they were simply too small. They are only 1/10,000 inch in size or less."

In 2005, two powerful new nano-technology instruments were installed in the scientists' laboratory at Johnson Space Center. The organic globules were first found in ultrathin slices of the meteorite with a new JEOL transmission electron microscope. It provided detailed structural and chemical information about the globules. The organic globules were then analyzed for their isotopic compositions with a new mass spectrometer, the Cameca NanoSIMS, the first instrument of its kind capable of making this key measurement on such small objects.

The organic globules in the Tagish Lake meteorites were found to have very unusual hydrogen and nitrogen isotopic compositions, proving that the globules did not come from Earth.

"The isotopic ratios in these globules show that they formed at temperatures of about -260° C, near absolute zero," said Scott Messenger, NASA space scientist and co-author of the paper. "The organic globules most likely originated in the cold molecular cloud that gave birth to our Solar System, or at the outermost reaches of the early Solar System."

The type of meteorite in which the globules were found is also so fragile that it generally breaks up into dust during its entry into Earth's atmosphere, scattering its organic contents across a wide swath. "If, as we suspect, this type of meteorite has been falling onto Earth throughout its entire history, then the Earth was seeded with these organic globules at the same time life was first forming here." said Mike Zolensky, NASA cosmic mineralogist and co-author of the paper.

The origin of life is one of the fundamental unsolved problems in natural sciences. Some biologists think that making a bubble-shape is the first step on the path to biotic life. "We may be a step closer to knowing where our ancestors came from," Nakamura-Messenger said.

- end -

Original release at: www.nasa.gov/centers/johnson/news/releases/2006/J06-103.html

Those few scientists who claim that there is no organic matter on Mars should try to explain what miracle would have preserved that planet from such contamination.

Mars exoplanetology and exobiology at LPI/NASA seminar:

More than a hundred of scientists participated in the "Second Conference on Early Mars: Geologic, Hydrologic, and Climate Evolution and the Implications for Life" conference on October 11-15 in Jackson Hole, Wyoming, hosted by the Lunar and Planetary Institute (LPI), NASA, and NASA's Mars Program Office.

LPI planetary scientist Steve Clifford said: "One of the most significant new findings reported at the meeting was that it appears Mars underwent many of its most important changes much earlier in its history than previously thought." On the fast core formation, the development of the crustal dichotomy and the fast decline in the geothermal system heat flow, he said:

"Surprisingly, all of these events appear to have occurred within the planet's first 50 million to 100 million years of existence," and this was related to the discovery of the potential role played by large impacts during this same period.

He said simulations indicate that the very largest of these impacts may have blown away a significant fraction of the early Martian atmosphere. Impacts that produced the largest craters might have affected the climate on a regional and global scale, creating transient environmental conditions capable of sustaining continuous rainfall lasting from years to decades.

He added: "There now appears to be overwhelming evidence that early Mars was water-rich – and may have possessed standing bodies of water and ice that ranged from large seas to a primordial ocean, perhaps covering a third of the planet."

Supporting evidence ranges from orbital observations of extensive layered terrains within, and possible paleoshorelines surrounding, the northern plains to on-the-spot investigations of the mineralogy and sedimentary record recently discovered by the Opportunity rover in Meridiani Planum.

"The implications of these findings are just beginning to be absorbed by the Mars community, yet they have already substantially revised our understanding of the planet's early evolution."

Lynn Rothschild, a scientist in the Ecosystem Science and Technology Branch of NASA's Ames Research Center said: "Life is incredible and the envelope for what we know about where life can live - data from planet Earth - is ever expanding and is far beyond what we might have hypothesized. There is a difference in perspective between planetary folks and biologists regarding where life might thrive. Organisms don't look for a global average. As a microbe, just give me 100 microliters of liquid water and I am happy. In any case, I certainly don't need an ocean! So think microenvironment."

The scientists agreed that the Odyssey and Spirit recent mission have shown evidence for Water and energy for microorganisms. The results indicate that there were both large bodies of liquid water on Mars and there were fluids carrying oxidizing and reducing gradients through the near surface which resulted in precipitation of the blueberries. Some wondered for how long the favorable conditions for life existed.

Panspermia was also much discussed. The scenario which appeared in the recent years gained support: life could have originated on Mars and was transferred to the Earth, and then went extinct on Mars.

Jack Farmer, an astrobiologist at Arizona State University in Tempe, said in an interview to Space.com that the idea that Mars could have played host to Earth-launched microbes, as well as being a planet where a second genesis might have also taken place "are both contenders for an origin of Martian life and deserve serious consideration."

"I also think the idea of a ‘War of the Worlds' on Mars between life forms that originated there and those that arrived from Earth is a serious possibility. And that prospect, he continued, raises some key questions: Who would win? Is there the possibility for a competitive co-existence between life forms that originated on a different basis?"

"The good news is these alternative hypotheses appear to be testable in the context of future missions. But this discussion also points, again, to the importance of planetary protection and the potential for back-contamination arising from a Martian sample return."

Read space.com's article at http://www.space.com/scienceastronomy/mars_life_041213.html

The meeting's website: http://www.lpi.usra.edu/meetings/earlymars2004

See also here and here.

The "not found" ammonia on Mars found at ESA's website:

Here is a good one.

ESA's Professor Formisano found ammonia on Mars, said BBC News. Then, Nature magazine said Formisano now insists he has not discovered ammonia on Mars (see previous news on this page).

On the ESA web site, the contrary was published:

http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=34633

"One composite PFS spectrum generated from over 1600 measurements. Revealed is the detail of the existing data and indicates some of the unanswered questions. The gaseous species are indicated: CO, CO2, H2O, HDO, NH3, S is for solar line. The solar spectrum is essentially unknown in half of the PFS region - these are the first space measurements at medium spectral resolution of the solar spectrum. To determine if a line is of solar, or Martian origin is a challenging task. There are many regions with features detected that are not yet identified."

Ammonia is practically proof that there is existing life on Mars (in addition to the many other evidence, see the rest of the Mars section).

Here is the spectrum published by ESA showing ammonia, from their http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=34633 page:

Ammonia not found on Mars:

After the announcement by ESA's Dr. Formisano that his team has detected ammonia on Mars, journalists wanted to know more: indeed the discovery of ammonia would practically be evidence of present life since conditions on Mars degrade ammonia fast and there is no geological process which may produce it constantly.

However, Formisano has now insisted to science magazine Nature that he has not detected ammonia. He has only "optimistically suggested that his team might have done so" in a recent conference abstract.

Another scientist, Mike Mumma, said his team has spent ten years looking for ammonia and never seen it, and that Formisano cannot see it because the Mars Express instrument is not fit to see it.

Ammonia detected, one more evidence for current life on Mars:

The spectral signature of ammonia has been tentatively detected by the Planetary Fourier Spectrometer (PFS) sensor on board the Mars Express probe of the European Space Agency.

Exactly as methane, a previously detected clue of biological activity, ammonia cannot survive more than a few hours in the Martian atmosphere. This means it must be constantly produced.

Methane and ammonia are interpreted by opponents of the life on Mars theory as coming from active volcanoes. But no active volcano of volcanic hotspot has been found on Mars despite intensive search. The only known alternative is that ammonia and methane are biological products, probably from Martian microbes.

Professor Vittorio Formisano, responsible scientist for the Fourier spectrometer, is expected to release details of new findings from the PFS at an international conference being held next week in Paris.

The detection of ammonia comes just a few months after methane was found in the Martian atmosphere. Methane is another gas with a possible biological origin.

Ammonia is that it is a compound of nitrogen and hydrogen. Nitrogen is rare in the Martian environment. Because no ordinary form of terrestrial life can exist without it, the presence of ammonia is one more of the increasing number of evidence that there is some sort of biological activity on Mars today still.

A NASA scientist said, "there are no known ways for ammonia to be present in the Martian atmosphere that do not involve life."

(See announcement cancellation above).

Biological hotspots on Mars? Scientists wonders:

Science Frontiers report under the headline "Biological Hot Spots on Mars?" the research of M.J. Mumma of the NASA's Goddard Space Flight Center concerning the detection traces of gases in the atmosphere of Mars via the spectroscope.

As reported in my Mars section, Mumma has recently combined the results from two earth-based infrared telescopes, indicating that traces of methane, a gas which could not persist under Martian conditions exists in traces that strongly suggest biological sources. Mumma adds that the Martian methane is concentrated over one of the two regions near the equator that are extraordinarily rich in water mixed with the soil.

(Was) unofficial: methane, a tell-tale sign of life, found on Mars:

(Was) unofficial, (later confirmed in worldwide science media): methane, a tell-tale sign of life, has been found on Mars.

A leak from both NASA sources and ESA sources allowed several press agencies to learn that scientists at both NASA and ESA (European Space Agency) have independently discovered tantalizing sign that methane exists in the atmosphere of Mars.

This is a strong signal of life on Mars, it is a byproduct of biological metabolism and the scientists are quite excited since it is important evidence, and most would say a definitive proof, that alien microbes are living on Mars.

Because methane would be degraded by the intense ultraviolet radiation on Mars it has a relatively short photochemical lifetime. The implication is that organisms are living nowadays on Mars.

Neither NASA nor the European Space Agency (ESA) have announced the findings publicly yet, but specialists who have seen the data believe the discovery is genuine and could not resist talking around. So did Professor Formisano, of the Institute of Physics and Interplanetary Science in Rome, lead scientist of the ESA research on Mars.

The finding has been independently confirmed by Michael Mumma of NASA's Goddard Space Flight Centre in Maryland, who used powerful spectroscopic telescopes based on Earth.

This team has also said they detected variations in the concentrations of methane, with a peak coming from the ancient Martian seabed of Meridiani Planum, where the NASA rover Opportunity is exploring Mars currently. Asked whether the continual production of methane is strong evidence of a biological origin of the gas, Dr Mumma said: "I think it is, myself personally."

Both teams of scientists are now busy validating their results before their respective organizations are prepared to go public on the implications.

Spirit takes ground level temperature measurements:

The Spirit rover has taken ground level temperature measurement on Mars for the first time, NASA said Friday. Scientist Phil Christensen, the scientist tasked with the temperature readings, has stated:

"On the ground, the warmest temperature is around five degrees Celsius and the coldest is -15 degrees Celsius."

Let me add that in terms of seasons, it is only the beginning of spring on Mars at this time, not mid-summer.

Spirit images show what looks like muddy soil under the surface dust:

PASADENA, California, January 6, 2004 -- The rock-strewn floor of Mars's Gusev Crater blossomed into sharp view Tuesday with the release of the most detailed image ever obtained from the planet, taken by the rover Spirit's panoramic camera in a tantalizing foretaste of things to come.

One of the main composite images from the Spirit lander revealed a mysterious substance right at the rover's feet, which NASA scientists described as "strangely cohesive clay-like material" with unexpected textures. This soil material was exposed when the Spirit lander dragged its empty air bags across the Martian surface to retract them.

Lead rover scientist Steve Squyres of Cornell University, who is the manager of the mission at the Jet Propulsion Laboratory (JPL), has said: "The way the surface has responded is bizarre, I don't understand it. I don't know anybody on my team who understands it... It looks like mud, but it can't be mud."

The material appears to have been mashed and clumped, like moist and viscous mud, and was broken away in pieces at some spots. Squyres said one of the Viking landers of the 1970s might have seen something like it elsewhere on Mars. The small wheeled robot from the pathfinder also raised similar comments when people noticed it left what had the appearance of moist tracks.

Earth microbe is probably of Martian origin:

See full article here.

Life in simulated Mars conditions:

Tim Kral, a researcher at the University of Arkansas in Fayetteville, and his colleagues, have shown that methanogen microorganism can grow in atmospheric and soil conditions that resemble those on Mars, and that it suggests that life can thrive on Mars.

Methanogens survived in a thin atmosphere of hydrogen and carbon dioxide and in a special brew of volcanic ash altered to simulate the properties of Martian soil, including its density, grain size and magnetic properties. Methanogens, which thrive in some of the most inhospitable places such as peat bogs and sea floor vents, tap their energy not from the sun but from the oxidation of inorganic matter, in their case hydrogen and carbon dioxide.

Chris McKay of NASA's Ames Research Center in Moffett Field, California, noted that the Mars' atmospheric density is only a fraction of that in the test, which was half of the Earth's air pressure. He also said "But its an important step in the right direction and of course the particular microorganisms that they used are interesting since if there is subsurface life on Mars our best guess would be that it would be methanogens."

The Arkansas team plans to do more tests to simulate Mars conditions more closely, with increasingly lower atmospheric pressures, lower temperatures and high doses of radiation.

"Certainly they are getting results that look interesting, in terms of atmospheric testing, but terraforming, that's a pretty big leap" said Steve Theison, an astronomer at the University of Maryland in College Park.

"Still, the discovery of extremophiles has opened up windows to possible life forms in extreme sites in other solar systems, and also Europa and certainly Mars as well," said Theison.

"In that sense, this is really provocatively interesting. I look forward to seeing what happens when they get this as close to Mars conditions as possible," Theison said.

Numerous scientists now discover evidence of water on Mars in MGS images:

As the scientific Magazine Nature has now published the confirmed results from the Mars Odyssey probe that there are vast amounts of ice water melted in the 1st meter of Martian grounds near and under the pole, several scientist have acquired a "new look" at satellite pictures of Mars and have also suddenly "discovered" evidence of water based on their "new look" at the pictures, often adding some "we knew it" statements.

Not so long ago, the matter appeared much more controversial; I remember:

"...meanders and channels are not clear evidence for rivers, and flat "lakebeds" may simply be sediment traps for the giant gas and dust clouds," as conclusion from a researcher who proposed a completely dry Mars. They may be, but the argument was not an argument against presence of water whatsoever.

Other scientists had opposite view, and more surprises might come up:

"Contrary to what a lot of people say, our experiments show that water can exist in liquid form on the surface of Mars. This has a lot of implications about the possibility of life," scientist Kuznetz said in 2000, knowing about it thanks to spacesuits tests performed back in the 60s.

"In Valles Marineris, there could be a set of conditions where the sun angle, depth and temperature is just right, and where the atmospheric pressure is just high enough to sustain pools of water," he also said in 2000.

I just ask, is that it?

Internet mass media have widely reported the results f the Mars Odyssey water presence measurements, adding various and sometimes inconstant statements about the amount of water frozen in the soil: we have learned that if that ice melted, Mars would be covered with a 1.500 meter deep ocean, or a 300 meters deep ocean, or it would create a lake twice as big as Lake Michigan. The bottom-line is, the detection is only effective down to one meter below the surface and only speculation can me made about the quantity of water that probably exists deeper in the soil, which cannot be detected with the current method.

Gilbert L. Levin: The king has clothes.

While the announcement I referred to on 05.25.2002 has now be posted widely as "Mars water announcements" in the mass media of the Internet (BBC, space.com, etc.,) the "surprising" result would not surprise much those who have listened to Gilbert L. Levin or read the full story behind the Viking 1977 experiments on this site.

Today, Levin said to space.com:

"I am surprised that no mention was made of putting the Pathfinder data and the Odyssey data together," Levin told SPACE.com. "Pathfinder found the surface temperature of Mars to exceed freezing, and Odyssey reports near-surface ice over wide regions... including the Pathfinder landing area, and the Viking landing areas."

"Any physicist would tell you that, given water ice near the surface, a surface temperature above freezing, and a total atmospheric pressure above the triple point, liquid water must exist in the soil above the ice. Maybe only as moisture for part of the day, but the liquid water is enough to sustain the microorganisms the Viking Labeled Release experiment found."

The Odyssey findings clearly support, in Levin's view, that Viking provided data establishing the presence of liquid water on Mars under Martian surface conditions.

"The King has clothes! And as their blinders are gradually removed, even the most reticent scientists will suddenly discover that they knew all along that there is life on Mars," Levin told SPACE.com.

More on the Viking experiment story and life on Mars in the rest of my Mars section.

Meanwhile, I will continue to contemplate my still undiscovered favourite lake, at the equator, deep within Valles Marinensis where the air pressure may be high enough to ...

Another Mars water announcement coming soon:

Dr. Jim Garvin, Lead Scientist of NASA's Mars Exploration Program said that a major announcement is forthcoming about the presence of water ice just under the surface of Mars. Garvin made his comments at a Mars Exploration Breakfast sponsored on Capitol Hill by Lockheed Martin and Ball Aerospace on May 22, 2002.

The announcement depends on the process required to get the results reviewed and then published in a scientific journal. Garvin said that this was also being done out of respect for the principal investigator behind the announcement "who has been waiting twenty years" for this data.

Based on Garvin's hints, this could certainly be in reference to Professor William V. Boynton at the University of Arizona Lunar and Planetary Laboratory (regular visitors of my web site) who directed the design and construction of the Gamma Ray Spectrometer (GRS) now onboard the Mars Odyssey spacecraft. An earlier version of this instrument, built by Boynton, was aboard the ill-fated Mars Observer mission which stopped as it approached Mars in 1993.

In a press release in February 2002 Boynton said "I am really excited about finally getting to see real Mars data. I started this project in 1985, and now we are down to just hours before we see the results. I can imagine it must be like giving birth, except here we have a 17-year gestation period."

Garvin could also be referring, more likely, Bill Feldman, Los Alamos National Laboratory, whose team built the neutron spectrometer which is also aboard Odyssey. This instrument is designed to map the abundance of water in the upper meter of Mars' soil. Feldman's team also had a similar instrument aboard Mars Observer.

Garvin showed some new images, very similar to an earlier neutron graphic of Mars' south pole released in March 2002, which suggest that there is a lot of water just under the surface of Mars' northern polar regions as well. The view shown by Garvin was looking straight down at the north pole of Mars. The region where water ice is suspected to exist at the north pole extend much further to the equator (i.e. the deep blue portions of the image, indicative of soil enriched in hydrogen, was much larger) than they do in the initial neutron images of the south pole.

Earlier this year NASA scientists were stunned when the first data from Odyssey seemed to be showing abundant water ice just under the surface of Mars in the southern regions of the planet. According to a NASA statement issued at the time "the high hydrogen content is most likely due to water ice, though the amount of ice cannot be quantified yet. Further analysis will be conducted to confirm the interpretation."

NASA has scheduled a Space Science update for next Thursday, 30 May at 12:00 noon EDT- which is highly suggestive of the time a press embargo would lift for an article appearing in that week's issue of Science magazine.

The American Geophysical Union is holding its annual meeting in Washington, DC next week. There is a session starting at 1:30 EDT - just after the Space Science Update at NASA headquarters is going to conclude, a few blocks away, Boynton and Feldman will be presenting a number of jointly-authored papers: "Near-surface Ice on Mars: Early Results from the 2001 Mars Odyssey Gamma Ray Spectrometer (GRS) Instrument Suite" and "Global Distribution of Martian Volatiles During Northern Winter: Mars Odyssey Neutron Spectrometer Results."

Amino acid created artificially in simulated interstellar environment:

Amino acids obtained under conditions similar to those of the interstellar environment reinforce the theory that the first living organism on Earth were formed starting from organic molecules coming from interstellar clouds.

The work is originating from Dutch, French researchers and German who succeeded in producing them by photosynthesis and is announced by the magazine "Nature" in its March 28 issue.

In the laboratory of astrophysics of Leiden, in the Netherlands, the chemists recreated a medium similar to that they thinks existed four billion and half years ago around our planet, i.e. vacuum and cold (- 260°C). They placed there a frozen mixture composed of water, ammonia, methanol, carbon monoxide and carbon dioxide. This mixture, which represents grains of interstellar dust, was then irradiated with an ultraviolet ray lamp playing the part of the Sun.

The results of the experiment indicates that the organic molecules necessary for life on Earth can originate from space, and be brought to earth by meteorites or comets.

The components of the primitive atmosphere, very different from the current atmosphere, could transform them into organic compounds under the action of the ultraviolet rays of the Sun. These molecules then could dissolve in the water then react chemically between them, creating more complex compounds, proteins, glucids, lipids.

New evidence of water on Mars 3 feet under the surface in warm regions:

Leonard David, Senior Space Writer and Robert Roy Britt, Senior Science Writer have just announced that the Mars Odyssey spacecraft has uncovered preliminary yet tantalizing evidence for water near the surface of Mars and away from the permanently frozen north polar ice cap.

Readers of this site might have been convinced already, and maybe convinced of the presence of at least microbial surviving life on Mars as explained in the Mars section. All scientists already knew there is water ice in the Northern polar cap. Nevertheless, the announcement of this "discovery" is an important one as the scientific community was still divided on the possibility that water might exist on Mars, particularly so near to the surface.

A wide acceptance of the presence of water ice near the surface in warmer regions of the planet will be a remarkable and long-sought finding that would have broad implications in the debate about the presence of life on Mars today, for the search for extraterrestrial life and for the feasibility of human exploration of Mars.

The data, collected during tests of Odyssey's neutron spectrometer, show signs of hydrogen, which may or may not mean there is water. Hydrogen is one component of water but also exists alone and in other substances.

NASA researchers stressed that the findings are preliminary. They aren't sure exactly what the new data tell them, but they were optimistic enough to discuss the research this week at a meeting of the American Geophysical Union in San Francisco.

The detection of hydrogen points to the possibility that there is water ice within 3 feet (1 meter) of the surface, said James Garvin, lead scientist for the Mars Exploration Program at NASA Headquarters in Washington, D.C.

Particularly telling, is this phrase seen on the space.com web site about the discovery: "Such ice might melt in summer months and would be reachable by robotic or human explorers. It might even support microbial life, as researchers have found on Earth that wherever there is water, there is life."

Even more compelling: "The quantity of hydrogen detected was so startling - suggesting a huge concentration relative to what Feldman saw with a similar instrument on Lunar Prospector, which surveyed the Moon -- that researchers may task Odyssey to begin mapping crustal water ice during the first week January..."

It is also noteworthy that the real science program of the probe is not even started yet, as Odyssey is still in the middle of aerobraking, a task that will be completed around mid-January.

The hydrogen detection was made during the first test of Odyssey's neutron spectrometer, a subsystem of a gamma ray spectrometer instrument. The test pass covered an area from the equator to the north pole. The resolution of the observations were at 100 kilometers or more.

The northern ice cap shrinks in summer to as little as 1,000 kilometers in diameter. In winter, it ranges as far south as 60 degrees latitude. Odyssey detected hydrogen farther south, at 55 degrees. The poles are at 90 degrees and zero represents the equator. "This pass suggested that hydrogen was enriched in a high-latitude region extending from around 55 degrees North to near to the edge of the north polar cap, and that it was not enhanced over the north polar permanent cap," Garvin said. "This suggests, in a most preliminary sense, that if the hydrogen in the northern high latitudes is water, that there is ice in the upper meter or so of this region ... and that it is masked by a carbon dioxide frost cover on the permanent cap."

Just weeks ago, one top Odyssey scientist said the prospects for finding water near the surface of Mars represented a longshot. All that seems to have changed now.

Just one year ago I have located this site, on which NASA offers no comment.

NASA's Global Surveyor sees possible climate change on Mars:

There is no need to add much comment to this news item, I will simply reproduce the NASA announcement, to the word:

Mary Hardin
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone: 818/354-0344)

Tim Tawney
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/614-6573)

RELEASE: 01-240

NASA'S GLOBAL SURVEYOR SEES POSSIBLE CLIMATE CHANGE ON MARS

The planet Mars we know today is a cold, dry, desert world, but suppose the Martian climate is changing even now, year to year and decade to decade?

New observations by NASA's Mars Global Surveyor spacecraft are expanding understanding of the Martian climate and may indicate the climate is changing significantly even today. This suggests even larger climate changes have occurred during the planet's recent history and may again in its future. The observations were made during a full Martian year, 687 Earth days.

If this is so, Mars might someday become warmer and wetter, as some scientists suggest it was during its early history. Papers detailing these observations are published in the Dec. 7, 2001, issue of Science magazine.

"If the environment of Mars has really changed by as much and over as short a time-scale as our observation implies, there should be attributes of Mars reflecting these changes that may be measurable by landers," said Dr. Michael Malin, principal investigator for Global Surveyor's camera system at Malin Space Science Systems, San Diego. "If Mars had a higher atmospheric pressure in the not-too-distant past, it is more likely that water was present as a liquid near the surface."

Liquid water is required to support known forms of life, and the presence of liquid water on Mars would make it more likely life may once have existed there.

"Detecting evidence of climate change and variability on Mars using Mars Global Surveyor data is an important aspect of telling us where to go on the surface this decade," said Dr. James Garvin, NASA's Lead Scientist for Mars Exploration, Headquarters, Washington. "Clearly, the polar regions are a good place where we would like to look for hydrothermal vents to see if they exist on Mars."

Images from Global Surveyor's camera system show that pits -- often referred to as the "Swiss cheese" terrain -- at the southern polar ice cap of Mars have dramatically increased in diameter, indicating the material has evaporated rapidly compared to last year.

"The amount of change is much larger than any previous change we've seen on Mars and it is much larger than can be explained by the evaporation of water ice. We have calculated the only material that could have changed this much is carbon dioxide ice, what we know as dry ice," said Malin. "This means the Mars environment we see today may not be what it was a few hundred years ago, and may not be what will exist a few hundred years in the future."

A separate observation is providing more detail about the behavior of carbon dioxide in the Martian atmosphere. Carbon dioxide is a "greenhouse gas" believed to warm climates when its atmospheric concentration increases. The spacecraft's laser altimeter and radio tracking system have made precise measurements of the amount and density of carbon dioxide snow in both polar regions. This information gives scientists the first global measurement of the seasonal exchange of carbon dioxide between the atmosphere and surface.

Due to the tilt of the planet, Mars has seasons just like Earth. Scientists have long known the most important seasonal change on Mars is the autumn and winter "freezing out" of carbon dioxide from the atmosphere in the form of dry-ice frost and snow. The evaporation of the surface frost in spring and summer returns carbon dioxide to the atmosphere. Over the course of a Martian year, as much as a quarter of the atmosphere freezes out, but until now scientists didn't know precisely where and how much dry-ice frost and snow would pile up on the surface.

"We have measured how deep the dry-ice snow got on Mars over the course of a year. We have also measured the corresponding tiny change in the gravity field due to carbon dioxide being transported from one pole to the other with the seasons," said Dr. Maria Zuber, deputy principal investigator of the laser altimeter, at the Massachusetts Institute of Technology, Cambridge, and NASA's Goddard Space Flight Center, Greenbelt, Md.

"Snow on Mars is denser than snow on Earth and is really more like ice than snow. Understanding the present carbon dioxide cycle is an essential step towards understanding past Martian climates," Zuber said.

NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif., manages the Mars Global Surveyor mission for NASA's Office of Space Science, Washington. JPL is a division of the California Institute of Technology, Pasadena.

Latest new evidence of life on Mars in the past:

The book "Inside The Red Planet" by Dr Heather Couper and Nigel Henbest tells about the new conclusive evidence that life existed on Mars.

It explains how three Martian meteorites have now been analyzed by NASA scientists at the Johnson Space Centre in Houston, and how they found fossilized bacteria in them.

Some of the best new evidence comes from the Nakhla meteorite which landed in Egypt in 1911. The microfossils inside it are better than similar findings in meteorite ALH 84001 in 1996.

It becomes more and more accepted that life may have originated on Mars four billion years ago and then arrived on Earth, despite a recent widely reported announcement of a scientist that basically said he will check the meteorites in the future but there was no life on Mars.

NASA's Dr Everett Gibson quoted in the book says: "We opened it in a clean lab and inside it found samples of clays which are probably in the 600 to 700-million-year-old time frame. Within these carbonates and clays are structures and features that are even larger and better preserved than those we saw in 84001."

The scientific community has still to reassess the 1976 Viking in situ life detection experiments at the new lights of all the recent discovery, maybe it will then finally appear to all that there is still today at least a dormant bacterial life on Mars.

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