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The Planet Mars: Scientific Findings & Conjectures

Hey there!

This is an old story I just came across on the BBC website. Those pictures are very blurry - are they really dust devils or something more...?

Mars dust devils caught in action

One of the US space agency's robot rovers on the Red Planet has captured whirlwinds, or "dust devils", churning their way across the Martian plain.

Spirit recorded images of the dust devils on 15 and 18 April; and these have now been turned into an animation.

The movies give mission scientists their best look yet at these mysterious planetary phenomena as they swirl across the surface of the Red Planet.

The Spirit rover has been exploring Gusev Crater since January 2004.

It has been using its navigation camera to routinely check for dust devils and began seeing the whirlwinds last month in individual frames captured with the camera.

Kicking dust

Mission scientist Dr Mark Lemmon, a rover team member from Texas A&M University in College Station, said: "We're hoping to learn about how dust is kicked up into the atmosphere and how the wind is interacting with the surface.

"It's exciting that we now have a systematic way of capturing dust devils in movies rather than isolated still images."

Similar phenomena - also called dust devils - occur on Earth. The Martian whirlwinds also resemble the tornadoes and waterspouts seen on our own planet.

The ultimate cause of the Martian phenomena remains unknown, but may be related to rising air heated by sun-warmed rocks and soil.

Intriguingly, rover engineers have noticed unexplained increases in the power available to Spirit.

One possibility is that dust devils passing nearby or above the rover have been cleaning its solar panels.

Source
 
Martian volcanoes 'may be active'

Fields of volcanic cones discovered at the North Pole of Mars suggest the Red Planet could still be geologically active, scientists have said.

The cones, seen in images from Europe's Mars Express probe, have no blemishes from impact craters.

This suggests the volcanoes erupted very recently and that the sites could have ongoing volcanism.

Mars Express scientist Gerhard Neukum presented the results at a conference in Cambridge.

"Mars is a planet that was very recently active - maybe one, or two, or three million years ago. And in some areas, I have the impression it is really ongoing," said Dr Neukum, of the Free University in Berlin, Germany.

Future eruptions

But what cannot be determined is when, if at all, some of these volcanoes might erupt again: "It could be a million years from now, it could be tomorrow," he added.

Dr Neukum acts as the principal investigator for the High Resolution Stereo Camera (HRSC) on Mars Express, which took the images in which the cones were discovered.

There may be 50-100 of the volcanic cones covering a flank of the North Pole about one million square kilometres in area. They are between 300m (980ft) and 600m (1,970ft) tall, said Dr Neukum.

In addition to the North Pole, other regions with recent - and possibly ongoing - activity on Mars include parts of Tharsis - home to the volcano Olympus Mons - parts of Elysium and the so-called highland-lowland boundary.

By counting the number of craters on the surfaces of Solar System objects, scientists can estimate the age of those surfaces.

If they are heavily cratered, they are deemed older, while smoother surfaces are considered younger. This assumes a constant cratering rate since the heavy bombardment that terrestrial planets underwent about four billion years ago.

Fresh cones

The cones appear to be fresh with no discernible evidence of cratering. Dr Neukum admitted it was possible the cones could be ancient features that have been eroded by wind, but added that this was unlikely.

"I don't see any wind-related features in the region. We should see it and we should see the remains of craters somewhere. But we don't," he told the BBC News website.

Volcanic activity appeared to have peaked on Mars at around 1.5 billion years ago, Dr Neukum said, adding: "Mars is still active within certain limits; it's still not dead."

Dr Neukum thinks that volcanic activity strongly influences glacial activity on Mars. This is because on the Red Planet, eruptions also mobilise water.

In some cases, this water freezes and forms glaciers, says Dr Neukum. But other scientists believe glacial activity on the planet is more strongly influenced by the inclination of Mars in its orbit around the Sun.

The Mars Express results were presented at the American Astronomical Society Division of Planetary Sciences meeting in Cambridge, UK.

http://news.bbc.co.uk/1/hi/sci/tech/4219858.stm
 
Water Detection At Gusev Described

Water Detection At Gusev Described - Chemical Proof For Two Wet Scenarios

This mini-panorama was taken by Spirit on Aug. 23, 2005, just as the rover finally completed its intrepid climb up "Husband Hill." The summit appears to be a windswept plateau of scattered rocks, little sand dunes and small exposures of outcrop.
by Tony Fitzpatrick
St Louis MO (SPX) Sep 08, 2005
A large team of NASA scientists, led by earth and planetary scientists at Washington University in St. Louis details the first solid set of evidence for water having existed on Mars at the Gusev crater, exploration site of the rover Spirit.
Using an array of sophisticated equipment on Spirit, Alian Wang, Ph.D., Washington University senior research scientist in earth and planetary sciences in Arts & Sciences, and the late Larry A. Haskin, Ph.D., Ralph E. Morrow Distinguished University Professor of earth and planetary sciences, found that the volcanic rocks at Gusev crater near Spirit's landing site were much like the olivine-rich basaltic rocks on Earth, and some of them possessed a coating rich in sulfur, bromine, chlorine and hematite, or oxidized iron.

The team examined three rocks and found their most compelling evidence in a rock named Mazatzal.

The rock evidence indicates a scenario where water froze and melted at some point in Martian history, dissolving the sulfur, chlorine and bromine elements in the soil. The small amount of acidic fluids then react with the rocks buried in the soil and formed these highly oxidized coatings.

Trench-digging rover


During its traverse from landing site to Columbia Hills, the rover Spirit dug three trenches, allowing researchers to detect relatively high levels of magnesium sulfate comprising more than 20 percent of the regolith - soil containing pieces of small rocks - within one of the trenches, the Boroughs trench. The tight correlation between magnesium and sulfur indicates an open hydrologic system - these ions had been carried by water to this site and deposited.

Spirit's fellow rover Opportunity earlier had detected a history of water at another site on Mars, Meridiani planum. This study (by Haskin et al.) covered the investigation of Spirit rover sols (a sol is a Martian day) 1 through 156, with the major discoveries occurring after sol 80.

After the findings were confirmed, Spirit traversed to the Columbian hills, where it found more evidence indicating water. The science team is currently planning for sol 551 operation of Spirit rover, which is only 55 meters away from the summit of Columbia Hills.

Spirit was on sol 597 on Sept 6 and on the summit of Husband Hill.

"We will stay on the summit for a few weeks to finish our desired investigations, then go downhill to explore the south inner basin, especially the so-called 'home-plate,' which could be a feature of older rock or a filled-in crater," Wang said. "We will name a major geo-feature in the basin after Larry."

This mini-panorama was taken by Spirit on Aug. 23, 2005, just as the rover finally completed its intrepid climb up "Husband Hill." The summit appears to be a windswept plateau of scattered rocks, little sand dunes and small exposures of outcrop.

Wang, Haskin, their WUSTL colleague Raymond E. Arvidson, chair of earth and planetary sciences, and James S. McDonnell Distinguished University Professor, and Bradley Jolliff, Ph.D., research associate professor in earth and planetary sciences, and more than two dozen collaborators from numerous institutions, reported their findings in the July 7, 2005 issue of Nature magazine (Larry A. Haskin et al. Nature 436, 66-69 (7 July 2005) doi:10.1038/nature03640).

The paper was the last one that lead author Haskin, a highly regarded NASA veteran and former chair of earth and planetary sciences at WUSTL, submitted before his death on March 24, 2005.

Buried again and again


"We looked closely at the multiple layers on top of the rock Mazatzal because it had a very different geochemistry and mineralogy," said Wang. "This told us that the rock had been buried in the soil and exposed and then buried again several times over the history. There are chemical changes during the burial times and those changes show that the soil had been involved with water.

"The telltale thing was a higher proportion of hematite in the coatings. We hadn't seen that in any previous Gusev rocks. Also, we saw very high chlorine in the coating and very high bromine levels inside the rock. The separation of the sulfur and chlorine tells us that the deposition of chlorine is affected by water."

While the multilayer coatings on rock Mazatzal indicates a temporal occurrence of low quantity water associated with freezing and melting of water, the sulfate deposition at trench sites indicates the involvement of a large body of water.

"We examined the regolith at different depths within the Big Hole and the Boroughs trenches and saw an extremely tight correlation between magnesium and sulfur, which was not observed previously," Wang said.

"This tells us that magnesium sulfate formed in these trench regoliths. The increasing bromine concentration and the separation of chlorine from sulfur also suggests the action of water. We don't know exactly how much water is combined with that. The fact that the magnesium sulfate is more than 20 percent of the examined regolith sample says that the magnesium and sulfur were carried by water to this area from another place, and then deposited as magnesium sulfate. A certain amount of water would be needed to accomplish that action."

http://www.spacedaily.com/news/mars-wat ... e-05k.html
 
Ice Belt Encircled Mars' Equator

Study: Ice Belt Encircled Mars' Equator

2003 Hubble photo of Mars.
Cambridge, England (UPI) Sep 13, 2005
ESA's Mars Express space probe that entered orbit at the end of 2003 may have found evidence of a band of ice that once spanned the Martian equator.
Scientists says patterns of glacial activity on the planet may be a relic of an ancient belt of ice that formed about five million years ago due to a change in the tilt of Mars. That shift caused moisture from the poles to be deposited as snow at the equator.

The idea is based on work by a team of scientists led by astronomer Jacques Laskar of the Paris Observatory.

Laskar's team has shown the tilt of Mars on its axis can vary between 15 degrees and 40 degrees, largely because of its lack of a significant moon.

Researchers also found that when Mars' tilt changed to about 35 degrees, moisture trapped at the North and South Poles might have been re-deposited in equatorial regions as snow.

Eventually, the poles may have become smaller and a thick belt of ice formed around the tropics.

The study was detailed during the American Astronomical Society's Division of Planetary Sciences meeting this week in Cambridge, England.

Editor's Note: Due to a failure to correct a copy error during today's production, this report was issued with a mistake in the first paragraph where Mars Express was described as a NASA spacecraft. This is obviously not correct, and of course it should have read ESA. The chain on this error is long and goes all the way back to the original news article issued by the UPI news wire. My apologies to all concerned that this error was not picked up earlier by our editor's. SpaceDaily is very much aware that Mars Express is a flagship exploration mission for ESA, and we very much look forward to the momenteous discoveries the MARSIS radar will soon be making.

All rights reserved. © 2005 United Press International. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by United Press International. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of United Press International.

http://www.spacedaily.com/news/mars-wat ... e-05n.html
 
Drilling on Mars to find evidence of ancient organisms

Drilling on Mars to find evidence of ancient organisms: a second genesis of life?

Was there ever life on Mars? The answer to this question would do more than just satisfy curiosity. Researchers from NASA announce a plan to drill on Mars in search of ancient Martian organisms for comparison between life on Mars and life on Earth.

It is already theorized that life on Earth shares a common ancestor with life on Mars brought about by an exchange of material from meteorites. Evidence of life on Mars would strengthen this theory and give insight to origins of life on Earth.

Current research has focused on attaining fossils of Martian life which would only prove that life once existed on the planet. However, scientists from NASA and the SETI Institute believe that they can find out more information from Martian permafrost.

If researchers could discover dead, but intact organisms from Mars, biochemical and genetic analysis could be performed. These methods would provide a way for direct comparison between the life once found on Mars and the life currently found on Earth.

The best place to look for preserved Martian organisms is in the permafrost found on the Southern hemisphere of Mars. Heavily cratered, this terrain dates back to early Martian history when water was abundant and existence of life more likely.

Scientists at NASA have several obstacles to overcome as they plan this study. Mars is under strict planetary protection laws set forth by the Committee on Space Research (COSPAR). Any robotic drilling missions would need to utilize sterile equipment to avoid introducing biological material into the Martian environment.

Also, contamination of samples must be avoided to ensure that biological material taken from the permafrost was of Martian origin.

Before a drilling mission to Mars is underway, more research is needed to develop automated drilling systems or systems for human operation.

In the near future though, NASA hopes to find evidence of life on Mars. Could this evidence represent a second genesis of life, separate from that on Earth? The answers may be in the permafrost.

Reference:

Smith HD and McKay CP.
Planetary and Space Science Journal. 2005. Article in Press.

by Gina M. Buss, Copyright 2005 PhysOrg.com
http://physorg.com/news6505.html
 
Mars 'more active than suspected'

New images of Mars suggest the red planet's surface is more active than previously thought, the US space agency Nasa has announced.
New photographs from Nasa's orbiting spacecraft, Mars Global Surveyor, show new impact craters and gullies.

The agency's scientists also say that deposits of frozen carbon dioxide near the planet's south pole have shrunk for three summers in a row.

They say these changes suggest climate change is in progress.

'Marsquakes'

"To see new gullies and other changes in Mars surface features on a time span of a few years presents us with a more active, dynamic planet than many suspected," said Nasa's Michael Meyer.

The newly released images also show boulder tracks at another site, which were not there two years ago.

Michael Malin, principal investigator for the Mars Orbiter Camera, said it was the first evidence scientists had seen of some kind of seismic activity on the planet.

The Mars Global Surveyor has been orbiting the planet since 1997; Nasa expects it to carry on doing so for another five to 10 years.

http://news.bbc.co.uk/1/hi/sci/tech/4266474.stm

 
Landslips, impacts and eroding ice revealed on Mars

The landscape of Mars is changing faster than thought, earthquakes may be rattling the planet and global climate change may be eroding polar ice, new observations by the Mars Global Surveyor spacecraft show.

The images reveal gullies appearing in sandy dunes, and boulders perched atop a dusty slope one year are in a rubble pile at the bottom the next. Mars is also still being slammed by a few meteorites, as new craters prove. And carbon dioxide ice at the south pole appears to be shrinking, possibly due to global warming.

To mark MGS's eighth full year in orbit, NASA has released a new suite of pictures. An April 2005 picture of a sand dune shows a pair of 800-to-900-metre-long gullies not present in a July 2002 picture. The gullies may have formed after pockets of frozen carbon dioxide in the sand thawed in the spring and caused the sand to flow downhill like a fluid.

In 2000, MGS images caused a stir by revealing gullies up to two kilometres long on crater walls and valleys in regions above 30° latitude. At the time, it was thought that water under pressure near the surface could have sprouted up and cut the gullies. But later research indicated that carbon dioxide or dust avalanches may have been to blame.

Scientists were not able to determine precisely when those gullies formed, but MGS's longevity has enabled it to detect changes. The new images show "at least one type of gulley can form under the current conditions, and that's very exciting", says planetary geologist Jack Mustard at Brown University, Rhode Island, US.

Rolling stones
MGS also saw that more than a dozen boulders rolled down a crater wall in the span of 13 months. The boulders could have been felled by high winds or shaking from a meteorite impact, although the spacecraft did not spot any new craters nearby.

Michael Malin, chief scientist of the spacecraft's Mars Orbiter Camera, adds another theory: "Seismic activity would be my guess." If so, it would be the first evidence of current seismic activity on Mars.

It would suggest "a planet which is still warm enough to have movement in its interior", say Mustard. "That could allow us to contemplate that volcanism is still occurring."

The twin Viking landers had seismic instruments, but neither of them worked properly. The rovers currently working on the surface were not fitted with seismographs because their own movements would interfere with the readings.

Retreating ice caps
Another phenomenon revealed by the MGS images is the growth of pits in the carbon dioxide ice at the Martian south pole. Each year, these escarpments are losing about 3 m. The ice caps may be retreating due to a long-term warming of the planet, researchers suggest. View the changing shape of the ice here (8MB GIF).

Finally, MGS found a crater on Mars that did not exist when the Viking 2 spacecraft flew over the area in 1976. The crater, which is 20 metres in diameter, could have been made by a meteorite less than 1 m across.

These latest images are unlikely to be the last from MGS. Despite its relatively old age, the spacecraft does not show any signs of deterioration and it has enough propellant to last well beyond 2010.

http://www.newscientistspace.com/article.ns?id=dn8029
 
Deciphering Mars: The Future

Deciphering Mars: The Future

'Under the existing strategy, after MSL (illustrated), potential science pathways diverge, contingent on what we find out'.
A Talk by Jack Farmer
Moffett Field (SPX) Sep 27, 2005
The Mars Science Laboratory, to be launched in 2009, is regarded as a keystone mission that marks the transition to the next decade of exploration.
With this mission, to take our exploration for past or present habitable environments and life on Mars to the next level, we will need to respond to discoveries made by the present-decade missions. Under the existing strategy, after MSL, potential science pathways diverge, contingent on what we find out.

I'm going to run through several different scenarios described in a report entitled "Mars Exploration Strategy 2009-2020." This report, published last year by NASA's Mars Science Program Synthesis Group, headed by Dan McCleese, identified a number of alternative exploration pathways. The pathway we follow will come out of what we're learning now.

Continue the Search for Evidence of Past Life. This is an approach we might follow if the present-decade missions going on now confirm that ancient Mars was habitable for extended periods of time.

By this time it is assumed we will have identified a whole bunch of places where we can go to look for fossil biosignatures in ancient rock sequences. I think we've already gotten indications that we might be, at least in part, on this pathway.

Explore for Ancient Hydrothermal Habitats. The discovery of modern or ancient hydrothermal environments in the present decade, might lead us to send missions to this very specific, and highly regarded environment.

Search for Present Life. If we discover modern habitat, say active hydrothermal systems capable of supporting life, we would have to start thinking seriously about in situ life detection and Mars sample return, which is perhaps the most reliable way of detecting life and understanding it. Of course, this discovery would also bring along important planetary protection issues to address: how to mitigate the risks of forward or back contamination.

Explore the Evolution of Mars. This is a pathway we might follow if in the present decade we failed to find evidence for past or present liquid water environments, at least long-lived environments that are capable of supporting life. I don't think we're on this pathway any more. I think we've obliterated this possibility with the results from recent missions.

The nice thing about this pathway analysis is that it was done considering cost constraints, to make it as realistic as possible. For example, for the "search for evidence of past life" pathway, there's a set of missions going out to 2020. This pathway has a Mars sample return in 2016. It's bounded on either side by Mars Scout missions, so that we can afford to do that, because this kind of initial sample return is going to be expensive. Under this scenario, deep drilling comes in 2020.

For the "explore for hydrothermal systems" pathway, there is an alternative set of missions. If we found hydrothermal systems, we'd have a mission in 2013, called the Astrobiology Field Laboratory, that would look for biosignatures in rocks. And out in 2018 deep drilling is identified as a possibility, particularly if we're trying to get into subsurface hydrothermal systems.

The discoveries that have been made just in the last year have somewhat outdated the pathways document. So the community is organizing to develop another set of scenarios that will take into account the discoveries that have occurred, so that the options that we have on the table are truly discovery-driven.

So, to summarize, what have we learned? Mars has had a prolonged aqueous history with widespread surface water during its early period, and hints of a subsurface hydrosphere through much of its younger history, possibly up to the present time. What do we need to know? We still have a lot to learn about the availability of basic nutrients and energy sources in both surface and subsurface environments, essential information for reliable assessment of habitability.

What are the steps we need to take to move toward extant life detection? Ultimately, that's what we're really shooting for. One vital step is to provide flight-ready instrumentation for definitive in-situ life detection at Mars. The astrobiology community is just starting to awaken to the need to develop new approaches to life detection and get them on the discussion table, and to mature those instruments very quickly for flight readiness.

One study has shown that it takes about 8 years from concept to flight, to get an instrument to Mars. So if we want to be out there in the middle of the next decade with a life-detection instrument, we have to be developing that instrumentation now!

We also need to obtain a more thorough understanding of the potential for forward contamination of Mars and how to mitigate against false positives. Carrying some level of "bio-load" with us to Mars is probably unavoidable. We have to know how to deal with that. The whole idea of planetary protection, whether forward to Mars, or backward to the Earth, is still in its infancy as far as actual implementation is concerned.

We need to conduct the first in-situ life detection surveys on the surface of Mars at locations that have proven to be past or present habitable environments. We're still identifying the places to go. Where we want to go may be very difficult to get to and missions will probably need to be specifically designed to go there.

That's technology that needs to be developed as well. If we're going to the subsurface, we have to develop sterile drilling methods to search for subsurface ground water, biochemistry and life.

Eventually, we want to undertake targeted sample returns from high-priority sites where we think we may have detected life, so we can characterize that life in Earth-based labs. But that introduces another whole set of problems, because of the potential for planetary back contamination.

So these are things that have to be dealt with. Now, we have a new presidential initiative. The idea is to get humans to the moon by 2020 and use that as a stepping-stone for humans to Mars by 2030. We'll see what happens. But perhaps one of the most important scientific justifications for sending humans to Mars may be the exploration of the deep subsurface.

It may simply prove impossible - it seems very difficult right now - to drill to multiple-kilometer depths with a robotic system. Maybe that will change, but there will need to be a lot of technology development. It may be much easier to send humans to Mars to run drilling rigs. But we have to be very careful about what we're doing, because the back-contamination issues are really a problem when you talk about human exploration. How do you decontaminate an astronaut?

So there are lots of things to consider for the second decade of exploration. But we're on a path, a phased program of exploration. We've had very interesting discoveries and I think we're going to have a lot more. MRO is going to open a lot of eyes with this new data that we're going to get, data complementary to Mars Express. So I'm very excited about the future of Mars exploration, and I hope you are too!

http://www.spacedaily.com/news/mars-future-05s.html
 
Sailing the planets: Exploring Mars with guided balloons

Sailing the planets: Exploring Mars with guided balloons

Mars rovers, Spirit and Opportunity, have, by now, spent almost two years on the surface of Mars. They traveled several miles each, frequently stopping and analyzing scientific targets with their cameras, spectrometers and other instruments to uncover evidence of liquid water on Mars in the past. Their mission is a smashing success for NASA.

But what if NASA had a platform on Mars that was able to cover these distances in a matter of hours instead and study the rocks on the surface in the same detail as rovers do? Scientific return from such a vehicle would be immense – scientists would be able to study the whole planet in greater detail in a time span of a single year.

While orbiters can look at virtually any point on the surface of a planet, they lack the resolution provided by instruments on rovers or landers. Rovers, on the other hand, have limited mobility and cannot travel very far from their landing site. As the atmosphere of Mars is very thin, an airplane at Mars would last for just an hour until it runs out of fuel.

Global Aerospace Corporation of Altadena, CA proposes that the Mars exploration vehicle combining the global reach similar to that of orbiters and high resolution observations enabled by rovers could be a balloon that can be steered in the right direction and that would drop small science packages over the target sites. The concept being developed by the Global Aerospace Corporation is funded by the NASA Institute for Advanced Concepts (NIAC).

Balloons have been long recognized as unique, scientific platforms due to their relatively low cost and low power consumption. Two balloons flew in the atmosphere of Venus in 1984. In the past the inability to control the path of Mars balloons has limited their usefulness, and therefore scientific interest in their use.

Global Aerospace Corporation has designed an innovative device, called Balloon Guidance System (BGS) that enables steering a balloon through the atmosphere. The BGS is an aerodynamic surface – a wing – that hangs on a several kilometer-long tether below the balloon. The difference in winds at different altitudes create a relative wind at the latitude of the BGS wing, which in turn creates a lifting force. This lifting force is directed sideways and can be used to pull the balloon left or right relative to the prevailing winds.

Floating just several kilometers above the surface of Mars, the guided Mars balloons can observe rock formations, layerings in canyon walls and polar caps, and other features – at very high resolution using relatively small cameras. They can be directed to fly over specific targets identified from orbital images and to deliver small surface laboratories, that will analyze the site at the level of detail rovers would do. Instruments at the balloon's gondola can also measure traces of methane in the atmospheric and follow its increasing concentrations to the source on the ground. This way the search for existing or extinct life on Mars can be accelerated.

http://www.physorg.com/news6816.html
 
Desert RATS Test Robotic Rover

Desert RATS Test Robotic Rover

by Henry Bortman
Moffett Field CA (SPX) Sep 30, 2005

Until earlier this year, when President Bush announced an ambitious blueprint for space exploration, NASA had no plans to send humans back to the moon, or to Mars.
But that didn't stop an intrepid group of scientists, based at NASA's Johnson Space Center in Houston, Texas, from investigating technologies that would be needed for such a mission.

Every year for nearly a decade, they have trekked out to remote desert locations to conduct research on equipment and procedures that might some day be used by off-world explorers. The skunkworks project, known as Desert RATS (Research and Technology Studies), has just completed its eighth field season, on a barren cattle ranch near the rim of Meteor Crater, some 40 miles outside Flagstaff, Arizona.

It's hard to find places on Earth that simulate Martian conditions. But the Arizona high desert comes close enough for the experiments the Desert RATS team conducted during the first two weeks of September.

According to Joe Kosmo of Johnson Space Center, who has led the Desert RATS effort since its inception, Meteor Crater is an ideal test site because if you "strip away the vegetation, put the atmospheric pressure at 100,000 feet, and put the sun a little farther away, essentially you're encountering the kind of terrain you'd see on Mars," Rough, slightly hilly desert hard pack, with an assortment of rocks and boulders strewn about. And dust (red, of course). Dust everywhere, blowing around in heavy gusts, making dust devils and coating everything in site.

This year's two-week field test focused on the interaction between a pair of "astronauts" (actually, space-suited scientists) and a rover named SCOUT (Science Crew and Operations Utility Testbed).

When astronauts travel to the moon or Mars, they will be going to do pretty much the same things a geologist does when exploring a field site on Earth: walking around, observing land formations, taking pictures and collecting rock and soil samples. But unlike on Earth, where even at the most remote locations, help is usually not far away, off-world explorers will have severely limited resources. Moreover, they will want to investigate as much terrain as possible, so conserving energy to focus on scientific tasks will be important.

"We're trying to augment the human-machine cooperative working relationship so that the machines can do a lot of the tedious tasks," says Frank Delgado, project lead for SCOUT. For example, by using SCOUT to drive explorers "to the location where they need to do their science, when they get there, they're a lot fresher."

SCOUT looks like an oversized dune buggy. Its design is loosely based on the Moon Buggy used by astronauts on the Apollo 15, 16 and 17 missions back in the 1970s. Its seats are built to accommodate two passengers wearing bulky spacesuits. Its joystick and computer touch screen are optimized for easy use by heavily gloved hands. And it is tricked out with an eclectic array of cameras, speakers and a host of communications gear. Its maximum ground speed: 6 miles per hour.

SCOUT had its first real-world test during the 2004 Desert RATS field season, but in that initial shakedown it was driven under manual control. "We basically focused on having somebody drive it from onboard," says Delgado. "So if you needed to get to a crater or somewhere to collect some rocks, they would jump onboard, and they'd drive it."

This year the RATS team tried out several automated modes of operation, including tele-operation, voice commands and gesture recognition. The field tests, which were highly successful, were the first ever that involved such complex interaction between humans and a semi-autonomous robotic assistant.

One type of tele-operation involved operating the rover in real- or near-real-time from a remote location. The operators used a joystick and a set of switches, knobs and buttons to control the rover as though they were onboard. Delgado's team was able to tele-operate SCOUT in this way both from a Desert RATS command center located about a half-mile from the test site and from a control center about 1200 miles away at the Johnson Space Center in Houston.

This is a feasible approach for operating a robotic rover on the moon from a lunar base or even from Earth. It could also be used by humans operating a rover from a local command base on Mars. It wouldn't be possible to tele-operate a Mars rover from Earth in real-time, however, because it takes too long for radio-command signals to get from one planet to the other.

Earth-based scientists could tele-operate a rover on Mars using batch commands, however. For example, "You can say, Go to waypoint 1, take a picture; go to waypoint 2, take a panorama; go to waypoint 3; and then come back home.' And it will do that automatically," says Delgado.

This is similar to the way in which mission controllers operate the Spirit and Opportunity rovers currently exploring Mars. But sending commands to Spirit and Opportunity requires first going through a laborious process of translating science-team requests into a sequence of arcane commands in a specialized language that the rovers can understand. SCOUT can understand direct voice commands.

Perhaps the most intriguing mode of operation that Delgado's team successfully tested was a procedure known as "human following," in which the rover followed one of the scientists as he explored on foot. To initiate human following, the scientist stood in front of the rover and said, "SCOUT, follow me." Onboard the rover, Delgado explains, is a pair of stereo cameras and a computerized shape-recognition system that knows "what a person should look like.

It locks onto them and as they walk around in front of the vehicle, the cameras will swivel to that direction. If they walk away from the vehicle, the vehicle actually follows them, like a pack mule. So if they're doing some sort of geological expedition and they're going to go out a half mile or a mile, the vehicle will be right there for them to get back on, instead of them having to walk all the way back."

Delgado's engineers also got SCOUT to respond to commands issued in the form of gestures. One of the scientists stood in front of the rover and put out his arm, as though signaling for a left turn. SCOUT recognized the gesture and turned on its lights. When the scientist bent his arm at a 90-degree angle, SCOUT turned the lights back off.

This was only a proof of concept, but it holds great promise. For example, says Delgado, an astronaut could point to an interesting rock and say, " Take a picture of that.' [The rover] will see where their finger's pointing and it'll turn the cameras in that direction and take a picture."

Although future missions to the moon and Mars will utilize vehicles with SCOUT-like capabilities, SCOUT was built as a testbed, and not as a prototype of a rover for a future mission. "There's a lot of basic functionality in the vehicle," Delgado explains, "that's there to support some of the concepts that we're trying to develop - the autonomous operations, tele-operations, obstacle avoidance, human following."

But features like rubber tires with air in them, or the rover's aluminum frame "would never be flown to the moon or to Mars." Moreover, the computer systems on SCOUT are built from off-the-shelf components. Hardware used on vehicles intended for spaceflight have to be specially designed for protection against dust, intense radiation and other severe conditions.

Still, the lessons learned in testing SCOUT will no doubt be applied to designing whatever rovers do get built to accompany humans on their return to the moon, and eventually to Mars.

http://www.spacedaily.com/news/mars-robot-05b.html

 
Mars Rovers May Yet Make Major Discoveries

Mars Rovers May Yet Make Major Discoveries

So far, Opportunity has driven more than 3 1/2 miles across Mars; while Spirit has driven 3 miles, the Monitor said.
Washington (UPI) Oct 03, 2005
NASA scientists in Washington have stopped making predictions about the Mars rovers Spirit and Opportunity as the devices continue to navigate across Mars.
Both devices represent a remarkable engineering feat as they continue to function nearly 1 1/2 years past their predicted expiration date, the Christian Science Monitor reported Monday.

Now the mission's lead scientist, Steve Squyres, believes the biggest discoveries lie ahead for the rovers. But, at the same time, Squyres is aware both machines continue to operate in an environment in which temperatures rise and fall daily by more than 200 degrees F.

Since the rovers have continued to function long after their projected expiration, scientists have stopped predicting when they will stop working. So far, Opportunity has driven more than 3 1/2 miles across Mars; while Spirit has driven 3 miles, the Monitor said.

Squyres says he believes they've lasted this long only because Martian windstorms have unexpectedly wiped away dust accumulating on their solar panels.

All rights reserved. © 2005 United Press International. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by United Press International.. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of United Press International.

http://www.spacedaily.com/news/mars-mers-05zzzze.html
 
Frozen Microbes Reveal How To Test For Martian Life

Frozen Microbes Reveal How To Test For Martian Life

"We tested equipment that we are developing to look for life on Mars and discovered a rare and complex microbial community living in blue ice vents inside a frozen volcano," remarked Hans E.F. Amundsen of Physics of Geological Processes (PGP) at the University of Oslo, Norway, and leader of the international AMASE team.

AMASE, the Arctic Mars Analog Svalbard Expedition, is designing devices and techniques to find life on Mars. Their test ground is Svalbard, (Norway) an area with a geology that is analogous to some Martian geology.

"The instruments detected both living and fossilized organisms, which is the kind of evidence we'd be searching for on the Red Planet," he continued. The AMASE expedition will be featured on Norwegian TV on October 6.

Science leader of AMASE, Andrew Steele of the Carnegie Institution's Geophysical Laboratory, explained that "ice-filled volcanic vents, such as these, are likely to occur on Mars and may be a potential habitat for life there."

The carbonate rocks found within the approximately 1-million-year-old Sverrefjell volcano on Svalbard are similar to carbonate rosettes found in the Martian meteorite ALH84001 and may have been produced by common processes. The blue ice, trapped in the volcanic vents, may represent samples of water that formed identical carbonate deposits in the Sverrefjell volcano.

The scientists detected living and fossilized microbiota, in the ice and on the surfaces and cracks of other volcanic rocks, using their integrated life-detection strategy successfully tested by AMASE in 2004. "Our instrument, designed by scientists at the Jet Propulsion Lab (JPL), detected minute quantities of aromatic hydrocarbons from microorganisms and lichens present in the rocks and ice," said Arthur Lonne Lane of JPL who made his 2nd voyage with the AMASE team.

Steele's team from Carnegie deployed a suite of instruments to detect and characterize low levels of microbiota. "We performed several successful tests with a miniaturized instrument fitted with special protein microarray chips," says Steele. "Our results showed that we were able to maintain sterile sampling procedures without introducing contamination from humans."

Coring of the blue-ice vents and surface glacial ice involved developing a detailed procedure for sterilization of the ice-coring tool. "The organisms found in ice are survivors! Small ecosystems in the ice have apparently adapted to extremely cold conditions," says Liane Benning, University of Leeds. The ice and rock samples will be characterized further in labs at the Carnegie, the Smithsonian Institution, PGP, Penn State, and University of Leeds.

This summer's AMASE expedition also involved interdisciplinary studies of the world's northern-most thermal springs above sea level, rock weathering and pattern formation, and biota in glacial ice by the physicists, geologists, chemists, and biologists on the team.

The AMASE group sampled sedimentary rocks that are roughly 780 million-year-old, which contain remarkable remains of microbial structures that still maintained morphologic structure.

"These rocks hold potential chemical markers of fossilized life. If there is similar evidence in ancient rocks on Mars, our equipment will be able to find it," says Marilyn Fogel, biogeochemist and astrobiologist at Carnegie.

The Arctic Mars Analog Svalbard Expedition (AMASE 2005) team comes from the following institutions: Physics of Geological Processes, University of Oslo; The Carnegie Institution of Washington, Geophysical Laboratory and Department of Terrestrial Magnetism; NASA Jet Propulsion Laboratory; University of Leeds; University of Oxford; Universidad de Burgos, Spain; The Smithsonian Institution; Penn State University; Geological Institute, University of Oslo and Idaho National Laboratory. The expedition photographer was Kjell Ove Storvik and expedition artist was Eamonn Shaw. AMASE 2005 included reporters from Die Zeit and Norwegian radio (NRK P2) and a film crew from Norwegian television (NRK1-Schrödingers Katt).

http://www.physorg.com/news6982.html
 
Mars' Climate In Flux: Mid-latitude Glaciers

Source: Geological Society of America
Date: 2005-10-18
Mars

--------------------------------------------------------------------------------

Mars' Climate In Flux: Mid-latitude Glaciers
New high-resolution images of mid-latitude Mars are revealing glacier-formed landscapes far from the Martian poles, says a leading Mars researcher.

Conspicuous trains of debris in valleys, arcs of debris on steep slopes and other features far from the polar ice caps bear striking similarities to glacial landscapes of Earth, says Brown University's James Head III. When combined with the latest climate models and orbital calculation for Mars, the geological features make a compelling case for Mars having ongoing climate shifts that allow ice to leave the poles and accumulate at lower latitudes.

"The exciting thing is a real convergence of these things," said Head, who presented the latest Mars climate discoveries on Sunday, 16 October, at the Annual Meeting of the Geological Society of America in Salt Lake City.

"For decades people have been saying that deposits at mid and equatorial latitudes look like they are ice-created," said Head. But without better images, elevation data and some way of explaining it, ice outside of Mars' polar regions was a hard sell.

Now high-resolution images from the Mars Odyssey spacecraft's Thermal Emission Imaging System combined with images from the Mars Global Surveyor spacecraft's Mars Orbiter Camera and Mars Orbiter Laser Altimeter can be compared directly with glacier features in mountain and polar regions of Earth. The likenesses are hard to ignore.

For instance, consider what Head calls "lineated valley fill." These are lines of debris on valley floors that run downhill and parallel to the valley walls, as if they mark some sort of past flow. The same sorts of lines of debris are seen in aerial images of Earth glaciers. The difference is that on Mars the water ice sublimes away (goes directly from solid ice to gas, without any liquid phase between) and leaves the debris lines intact. On Earth the lines of debris are usually washed away as a glacier melts.

The lines of debris on Mars continue down valleys and converges with other lines of debris - again, just like what's seen on Earth where glaciers converge.

"There's so much topography and the debris is so thick (on Mars) that it's possible some of the ice might still be there," said Head. The evidence for present day ice includes unusually degraded recent impact craters in these areas - just what you'd expect to see if a lot of the material ejected from the impact was ice that quickly sublimed away.

Another peculiarly glacier-like feature seen in Martian mid-latitudes are concentric arcs of debris breaking away from steep mountain alcoves - just as they do at the heads of glaciers on Earth.

As for how ice could reach Mars lower latitudes, orbital calculations indicate that Mars may slowly wobble on its spin axis far more than Earth does (the Moon minimizes Earth's wobble). This means that as Mars' axis tilted to the extremes - up to 60 degrees from the plane of Mars' orbit - the Martian poles get a whole lot more sunshine in the summertime than they do now. That extra sun would likely sublime water from the polar ice caps, explains Head.

"When you do that you are mobilizing a lot of ice and redistributing it to the equator," Head said. "The climate models are saying it's possible."

It's pure chance that we happen to be exploring Mars when its axis is at a lesser, more Earth-like tilt. This has led to the false impression of Mars being a place that's geologically and climatically dead. In fact, says Head, Mars is turning out to be a place that is constantly changing.

###
Lineated Valley Fill at the Dichotomy Boundary on Mars: Evidence for Regional Mid-Latitude Glaciation View abstract: glaciation
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Chamber Helps To Reproduce Conditions On Mars

Chamber Helps To Reproduce Conditions On Mars

"In a set of short term experiments ranging from one day to nearly two weeks in duration, quite a few microorganisms survived the harsh environment," said Thomas. His experiments were conducted with environmental conditions in the chamber (shown) set as it may be possible to make them in the future, rather than as they are believed to exist today.
Greenville IN (SPX) Oct 28, 2005
A little bit of mars has landed at SHOT, and it's open for business. Developed with support from the NASA Institute for Advanced Concepts (NIAC), the SHOT Martian Environment Simulator faithfully recreates the atmosphere, temperature and light spectrum found on the red planet.
Researchers from across the nation recently have begun conducting experiments inside the device's 5,673 cubic centimeter (346.2 cubic inch) pure quartz central chamber, which is a test bed for experimental ecopoiesis. Ecopoiesis is the starting-up of a planetary ecosystem based on Earth life. It also is a component of terraforming -- the creation of an Earth-like planetary environment.

"This new test bed opens up a world of planetary conditions for biologists and mineralogists to explore," Said, SHOT Chief Scientist Paul Todd, Ph.D. "Scientists can put simple life forms in it to determine their ability to survive on planets such as Mars."

To simulate the environment, the quartz test chamber is filled with the gas composition found on Mars -- more than 95 percent of which is carbon dioxide. The chamber can maintain the gas at as little as 10 millibars of atmospheric pressure. Earth's atmospheric pressure is 1,000 millibars.

The entire chamber is housed in an enclosure that uses liquid nitrogen to lower the temperature to minus 211 degrees Fahrenheit (minus 135 Celsius). Internal heaters raise it to a daytime Martian temperature of 78.8 degrees Fahrenheit (26 Celsius). A 1,000-watt xenon-arc lamp simulates the solar light spectrum that reaches the planet's surface.

"Replenishment of life support consumables for humans on planetary surfaces may enable long duration occupancy and exploration," said NIAC Director Robert A. Cassanova, Ph.D. "The SHOT team, led by Dr. Paul Todd, is exploring the concept of ecopoiesis which may eventually lead to the evolution of plant species that will thrive on planetary surfaces and provide these essential consumables for explorers."

SHOT has assembled an all-star team of Mars scientists to ensure that the system faithfully recreates the conditions that are the most interesting to researchers studying extremophiles -- organisms that are able to survive in extremely harsh environments. The scientific advisory committee includes Christopher P. McKay, Ph.D., and Lynn Rothschild, Ph.D., NASA Ames Research Center; Andrew Schuerger, Ph.D., University of Florida; Lawrence Kuznetz, Ph.D., NASA Johnson Space Center; Penelope J. Boston, Ph.D., New Mexico Institute of Mining and Technology and president of Complex Systems Research, Inc.; and David J. Thomas, Ph.D., Lyon College.

An associate professor of biology at the Batesville, Arkansas campus of Lyon College, Thomas recently concluded his first set of experiments in the chamber's red simulated Martian soil.

"In a set of short term experiments ranging from one day to nearly two weeks in duration, quite a few microorganisms survived the harsh environment," said Thomas. His experiments were conducted with environmental conditions in the chamber set as it may be possible to make them in the future, rather than as they are believed to exist today.

"If we can find a way to warm mars by four degrees Celsius, we can start a runaway greenhouse effect that will melt the ice cap and any other water frozen on the planet's surface.

The condition limiting life on Mars is dryness," said Thomas, who also serves as editor of Marsbugs, an online astrobiology newsletter.

Researchers interested in conducting experiments in the chamber at SHOT headquarters, or in installing a SHOT Martian Environment Simulator in their own laboratories, are encouraged to call 812-923-9591 x246 for more information.

Founded in 1988 as the result of a successful science fair entry, SHOT is an engineering and product development company. Its 27 full-time engineers, scientists and technicians are professional inventors.

The company specializes in providing a multidisciplinary systems approach to design challenges. SHOT mechanical, electrical, software, chemical, thermal, structural and systems engineers work as an integrated team – often together with the company's in-house chief scientist.

It serves several government agencies, universities and a growing list of commercial customers. SHOT has developed research payloads for seven space shuttle missions and three sub-orbital rocket flights.


http://www.spacedaily.com/news/mars-atmosphere-05e.html
 
life could exist on Mars

Methane found in desert soils bolsters theories that life could exist on Mars

Evidence of methane-producing organisms can be found in inhospitable soil environments much like those found on the surface of Mars, according to experiments undertaken by scientists and students from the Keck School of Medicine of the University of Southern California and the University of Arkansas and published online in the journal Icarus.

These results, they say, provide ample impetus for similar "biodetection experiments" to be considered for future missions to Mars.

"Methane-producing organisms are the ones most likely to be found on Mars," notes Joseph Miller, Ph.D., associate professor of cell and neurobiology at the Keck School and one of the study's lead researchers. "And, in fact, methane was detected on Mars last year."

Methane is considered to be a biological signature for certain living organisms that metabolize organic matter under conditions of low or no oxygen. Terrestrial methanogens (methane-producers) are typically found in environments largely protected from atmospheric oxygen, such as peat bogs, oceanic methane ices and anoxic levels of the ocean. But they had not previously been detected in an arid desert environment.

To see if methane could be found in Mars-like soil, the investigators collected soil and vapor samples from the arid environment of the Mars Desert Research Station in Utah, and then compared them with vapor samples taken from the Idaho High Desert and soil samples from Death Valley, the Arctic and the Atacama desert in Chile. Three of five vapor samples from the Utah site showed the presence of methane; there was no methane found in any of the vapor samples from Idaho. Similarly, while five of 40 soil samples from Utah produced methane after the addition of growth medium to the samples-indicating that the methane was being given off by a biological organism, most likely a bacterium-none of the other soil samples showed signs of methane production.

Finding methane in the Utah desert is no guarantee that methane-producers exist on Mars, admits Miller, who has previously analyzed data from the Viking Lander missions and found that soil samples taken in the 1970s from the Martian surface exhibited a circadian rhythm in what appeared to be nutrient metabolism, much like that present in terrestrial microbes. However, Miller says, this recent experiment does provide "proof of principle [in that] it improves the case that such bacteria can and might exist on the Martian surface." And that, he adds, surely warrants further investigation during future missions to Mars.

In conclusion, the researchers write, "The detection of methane, apparently of biological origin, in terrestrial desert regolith bodes well for future biodetection experiments in at least partially analogous Martian environments."

http://www.physorg.com/news7724.html

Source: University of Southern California
 
Work Bolsters Life On Mars Theories

Work Bolsters Life On Mars Theories

"Methane-producing organisms are the ones most likely to be found on Mars," noted Joseph Miller, associate professor of cell and neurobiology in the Keck School and one of the study's lead researchers.
By Lori Oliwenstein
Los Angeles CA (SPX) Nov 04, 2005
A Keck School scientist and his collaborators are the first to find methane-producing bacteria in arid desert soils, providing a springboard for future experiments on the distant planet.
"Methane-producing organisms are the ones most likely to be found on Mars," noted Joseph Miller, associate professor of cell and neurobiology in the Keck School and one of the study's lead researchers.

Evidence of methane-producing organisms can be found in inhospitable soil environments much like those found on the surface of Mars, according to experiments undertaken by scientists and students from the Keck School of Medicine of USC and the University of Arkansas and published online in the journal Icarus.

The results, they said, provide ample impetus for similar "biodetection experiments" to be considered for future missions to Mars.

"Methane-producing organisms are the ones most likely to be found on Mars," noted Joseph Miller, associate professor of cell and neurobiology in the Keck School and one of the study's lead researchers. "And, in fact, methane was detected on Mars last year."

Methane is considered to be a biological signature for certain living organisms that metabolize organic matter under conditions of low or no oxygen.

Terrestrial methanogens (methane-producers) are typically found in environments largely protected from atmospheric oxygen, such as peat bogs, oceanic methane ices and anoxic levels of the ocean. But they previously had not been detected in an arid desert environment.

To see if methane could be found in Mars-like soil, the investigators collected soil and vapor samples from the arid environment of the Mars Desert Research Station in Utah and then compared them with vapor samples taken from the Idaho High Desert and soil samples from Death Valley, the Arctic and the Atacama desert in Chile.

Three of five vapor samples from the Utah site showed the presence of methane; there was no methane found in any of the vapor samples from Idaho. Similarly, while five of 40 soil samples from Utah produced methane after the addition of growth medium to the samples – indicating that the methane was being given off by a biological organism, most likely a bacterium – none of the other soil samples showed signs of methane production.

Finding methane in the Utah desert is no guarantee that methane-producers exist on Mars, said Miller, who previously has analyzed data from the Viking Lander missions and found that soil samples taken in the 1970s from the Martian surface exhibited a circadian rhythm in what appeared to be nutrient metabolism, much like that present in terrestrial microbes.

However, Miller said, this recent experiment does provide "proof of principle [in that] it improves the case that such bacteria can and might exist on the Martian surface." And, he added, that surely warrants further investigation during future missions to Mars.

In conclusion, the researchers wrote, "The detection of methane, apparently of biological origin, in terrestrial desert regolith bodes well for future biodetection experiments in at least partially analogous Martian environments."


http://www.spacedaily.com/news/mars-life-05za.html
 
Simulations Show Liquid Water Could Exist on Mars



University of Arkansas researchers have become the first scientists to show that liquid water could exist for considerable times on the surface of Mars.

Image: This Petri dish contains the Mars soil stimulant used in the experiments inside the simulation chamber. Note the layers of ice and dust and the darkening of the dust. Also, water has flowed out onto the surface and in some places lies over dry soil. The mud forms a seal and helps retain water. Photos courtesy of Derek Sears.

Julie Chittenden, a graduate student with the Arkansas Center for Space and Planetary Sciences, and Derek Sears, director of the Space Center and the W.M. Keck Professor of Planetary Sciences, will report their findings in an upcoming issue of the Geophysical Research Letters.

"These experiments will help us understand how water behaves on Mars," Chittenden said.

Researchers have debated whether or not liquid water could exist on the surface of Mars because of the low temperatures and pressures found on the planet. Based on previous experiments and hypotheses, scientists have speculated that pure water on the planet's surface would evaporate from solid to gas, bypassing the liquid phase, at the low pressures found on Mars - 7 millibars as opposed to about 1,013 millibars on Earth. However, the planet's surface sports features like gullies and channels that look as though they might have been created by the movement of liquid. Terrestrial experiments designed to simulate Mars-like conditions have been performed to help answer this question of whether or not liquid water exists on Mars, but until this point they have only been done with pure water at high pressures.

Chittenden and Sears used a planetary environmental chamber in the W.M. Keck Laboratory for Space Simulation to simulate the conditions found on Mars - an atmosphere of carbon dioxide, 7 millibars of pressure and temperatures from zero degrees Celsius to 25 degrees below - and examined the evaporation rates of brine solutions expected to be found on Mars. Most water on Earth contains salts that leech into the water when it comes in contact with soil, and similar processes might be expected to occur in any surface water found on the Red Planet. Salts in the water lower the freezing point of the solution.

The University of Arkansas team placed the salt solutions in the planetary environmental chamber simulating Mars-like conditions, and then measured the evaporation rates at varying temperatures.




Image: This hydrogen distribution map from Los Alamos National Laboratories shows where hydrogen that may be tied up in water exists on Mars. Photos courtesy of Derek Sears.

"There's a huge decrease in the evaporation rate the colder it gets, more than anyone realized," Chittenden said. With the dissolved sodium and calcium in the water, the freezing point for the brine mixtures drops to 21 degrees below zero Celsius for salt water and 50 degrees below zero for water containing calcium chloride.

Temperatures on Mars vary between 125 degrees below zero Celsius and 28 degrees above at different latitudes and different times of the day. Thus, there is a possibility that liquid water could exist on the planet's surface at different locations and times of day.

"Brine formation could considerably increase the stability of water on Mars by both extending the temperature range over which liquid water is stable to negative-40 degrees Celsius and by decreasing the evaporation rates by two orders of magnitude," the researchers wrote.

Source: University of Arkansas

http://www.physorg.com/news7981.html
 
Making the Red Planet Green

Making the Red Planet Green By Rachel Metz
Story location: http://www.wired.com/news/technology/0, ... 02,00.html

02:00 AM Nov. 15, 2005 PT

Inside a chamber about the size of a small fridge in Greenville, Indiana, scientists are taking the first steps toward creating human settlements on Mars.

The chamber, called the Martian Environment Simulator, was put together by scientific engineering company SHOT and NASA's Institute for Advanced Concepts. Scientists are using it to determine how to grow plants in greenhouses on other planets, and hope it will eventually aid people living and working on Mars, as well as provide insight to the evolution of planetary life.

Not bad for a company whose start was inspired by a high school science fair project. One of SHOT's founders, John Vellinger, won an Indiana science fair in the early 1980s with a project on accommodating chicken embryos in space. This later led him to team up with Kentucky Fried Chicken engineer Mark Deuser on similar space shuttle experiments. Eventually, Vellinger and Deuser set out on their own with SHOT, which stands for space hardware optimization technology.

Since then, the company has worked with NASA on various vessels for space exploration, leading up to their current project on sustaining life in Mars.

If Martian settlements come to fruition, "you don't want to be existing based on resupply from Earth every so often -- you want to be able to grow your own food and live off the land," said NIAC director Robert Cassanova.

To do that, researchers must start small. They're currently experimenting with microorganisms, seeing how they react in conditions close to those on Mars, and slowly ramping them up to those of the red planet.

Their initial findings -- which showed some of these earthly microorganisms could survive for weeks in near-Mars conditions -- were reported at the American Society for Gravitational and Space Biology conference in Reno, Nevada, during the first week of November.

These organisms aren't exactly a vegetable patch, but they could be an important first step toward growing something on Mars. It's not an easy task, because plants are fickle and the planet isn't very flora- and fauna-friendly. Though its atmosphere is 95 percent carbon dioxide -- good for growing plants -- its pressure is less than 1 percent of that on Earth. Also, more ultraviolet light hits the surface of the planet than on Earth, and temperatures average around 32 degrees during the day.

Such conditions led researchers to focus on strains of earthly cyanobacteria, which can withstand harsh temperatures and tend to live far enough down in soil that they can avoid UV light damage but still perform photosynthesis, said SHOT chief scientist Paul Todd. Scientists are also testing a mix of cyanobacteria and soil bacteria known as "desert varnish," which includes organisms that live in the desert here on Earth and can also tolerate Mars' dry conditions.

"They've been pretty specially selected because of the extreme environments they can live in, and in some cases they're called extremophiles," Todd said.

These extremophiles are put into the simulator, a cryogenic cabinet containing a 6-liter quartz cylinder where the Martian environment is re-created.

The microorganisms sit in Earth soil that resembles Martian soil, with carbon-dioxide levels and temperatures consistent with conditions there. Martian days and nights are about as long as those on Earth, so the temperature and cycles of light and dark in the simulator are consistent with that, but seasons are twice as long, Todd said.

Unlike most other similar systems, the SHOT simulator can re-create Mars' day-to-night temperature and pressure cycles, he said. Researchers are conducting a five-week period of day-night cycles at approximately twice the pressure of that at the surface of Mars in the presence of a water-saturated environment, Todd said. Over time, scientists will bring these levels closer to Martian conditions so they can determine what microorganisms can survive best in such a harsh environment.

So far, "we've been able to take samples that have been in the chamber for a couple of weeks and detect what, for the moment, we'll call signs of life," Todd said.

Not everyone thinks human colonies on Mars are possible or very smart. Norm Sleep, a Mars expert and planetary scientist at Stanford University, said seeing what kinds of organisms can grow in a simulated Martian environment is a positive step toward learning about the evolution of life, but doing so to sustain human life on Mars is a mistake. Robots like current Mars rovers are more useful, he said.

We shouldn't be messing with Mars' environment, even in a greenhouse, Sleep said. It "makes about as much sense as a drug company using their clean room as a homeless shelter on the weekends."

Todd acknowledged concerns about contaminating Mars with Earth organisms. He also pointed out the usefulness of studying these bacteria -- they use carbon dioxide and are good at performing photosynthesis and producing oxygen under a wide variety of conditions.

"Research of this type has the potential of ultimately contributing to means of addressing global change," he said.
 
Seasonal Red Planet: NASA’s Spirit Rover Completes One Full Martian Year

By Tariq Malik
Staff Writer
posted: 22 November
7:00 a.m. ET



NASA’s Spirit rover currently exploring Mars completed one full swing around the Sun Monday, giving researchers a year-long look at the Martian seasons.



“We feel like, weather-wise, we’ve just about seen it all,” said Sharon Laubach, the rover’s integrating sequence team chief, in a telephone interview. “We’ve gone through all the seasons, we’ve survived Martian winter and gone through conjunction…yes, we’re having a party.”



While both Spirit and its robotic twin Opportunity hit the one Earth year mark of their mission in January, researchers said the Nov. 21 Martian anniversary holds far more significance for the long-lived rovers.



“It’s a big, important milestone,” said Steve Squyres, principal investigator of the rover’s science mission at Cornell University in Ithaca, New York in an earlier interview. “We’ll have acquired an entire year’s worth of observations.”



One Mars year is longer than Earth’s (about 687 Earth days), with Spirit hitting its anniversary on the 670th sol – or Martian day – of its mission. Spirit has rolled across 3.3 miles (5.4 kilometers) of Martian terrain at its landing site inside the planet’s Gusev crater.



Opportunity will complete its first Martian year exploring the plains of Meridiani Planum on Dec. 11, mission scientists said. Both rovers touched down on Mars in January 2004 on a primary mission that spanned 90 days.



Martian weather



Spirit and Opportunity are currently experiencing the final days of Martian summer and preparing for the onset of autumn, mission managers said.



During its first Martian year, Spirit found dust devils swirling across the planet’s landscape and frost settling on the its surface, researchers said, adding that the fringes of a major dust storm may have brushed Opportunity last month.



“So the planet, though it seems dead, does have a vibrant atmosphere,” explained Amitabha Ghosh, an atmospheric scientist and rover science team member with Gaithersburg, Maryland’s Tharsis, Inc.



Ghosh is using the mast-mounted Miniature Thermal Emissions Spectrometer (Mini-TES) aboard both rovers to study atmospheric changes depending on the Martian season.



“There are some really seasonal phenomena, like the dust devils,” Squyres said.



Mars researchers initially hoped to find many dust devils roaming across the Martian surface, but had to wait until early spring on the planet before the first whirlwinds were caught by Spirit’s cameras.



The infrared Mini-TES instrument, which is also used by geologists to determine Martian rock and soil minerals, records the temperature changes, dust levels and water vapor in Mars’ atmosphere. Mars researchers can also use each rover’s panoramic camera, which sits next to Mini-TES on the mast, to record dust devils, clouds and wind – which has apparently brushed the robot’s solar arrays clean from time to time.



“[We’re] trying to continue these routine measurements and, more importantly, look for patterns,” Ghosh told SPACE.com.



In general, Opportunity’s landing site seems to run a bit warmer than Spirit’s – about 4 to 6 degrees Celsius – while the surface temperatures at both sites hit their peak at noon local time, he said, citing rover observations.



Building a comprehensive understanding of Martian weather will be critical for future red planet expeditions, since wind, dust storms and other atmospheric phenomena can factor into a mission’s landing, Ghosh added.



A large dust storm that cropped up at Meridiani Planum in 2003 flung dust all the over to Spirit’s Gusev Crater landing site and reduced the density of the air there, forcing mission planners to alter the rover’s timeline for opening its parachute during descent.



Meanwhile, the weather on Mars should begin to turn as the landing sites for Spirit and Opportunity head further into fall.



In about 104 Martian days, or sol 775, rover handlers hope to have both rovers on Sun-facing inclines to maximize the amount of sunlight striking their solar arrays, Laubach said. The technique helped the rover mission weather the last Martian winter.



Spirit is currently rolling down Haskin Ridge as it descends from the summit of Husband Hill and makes its way toward a feature dubbed ‘Home Plate.’ Opportunity, meanwhile, continues to creep around Erebus Crater.



A far-off record



Despite their accomplishments, Spirit and Opportunity have a long way to go to set an endurance record on Mars. Both mission times pale in comparison with NASA’s twin Viking missions.



Viking 1 and Viking 2, both of which set down on Mars in the summer of 1976, spent several years recording Mars from their stationary landing spots. Viking 2’s mission ended in April of 1980 about 1,281 Martian days after landing when its batteries failed. Viking 1, however, continued to function until Nov. 13, 1982, more than four Earth years after arriving on Mars.



While their longevity is impressive, the Viking missions had a powerful – literally – advantage over Spirit and Opportunity. Both landers relied on radioisotope thermal generators (RTGs) that converted heat from decaying plutonium into electricity instead of solar arrays.



Dust buildup has gradually degraded the amount of power available from the solar arrays aboard Spirit and Opportunity. Both rovers were initially able to generate about 900 watt hours of power from the available sunlight, though dust has clouded their solar panels.



Spirit’s solar arrays currently produce about 650 watt hours while Opportunity’s generate up to 700 watt hours, Laubach said. A minimum of 300 watt hours is required for Spirit to function, though Opportunity can operate on slightly less, she added.



If Spirit and Opportunity continue to perform as they have for the last few weeks, it’s entirely possible that they could make it through January 2006 and their second Earth anniversary exploring the red planet, mission managers said.



“Though certainly they could die tomorrow, that’s just a fact,” Laubach said, adding that she and other rover team members have been amazed at the mission’s science output so far and hope for continued success. “We certainly haven’t seen everything there is on Mars.”



Mars
 
: NASA/Jet Propulsion Laboratory
Date: 2005-11-27
http://www.sciencedaily.com/releases/20 ... 121622.htm

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Meet The First Woman To Drive On Mars
If it weren't for severe motion sickness, Dr. Ashley Stroupe might already have several space shuttle flights under her belt. The child of an aerospace engineer, Stroupe devoured all things space-related during her childhood. Her higher education path literally led to the stars; astronomy was her first choice as an undergraduate, but the solitude of that profession lost out to the lure of robotics, where she would have the opportunity to help build and operate spacecraft that might one day visit the planets she studied through telescopes.

Right before the Mars Exploration Rovers made history, Stroupe joined JPL, and what a time to join the ranks. Holiday excursions were cut short or non-existent and the lab simmered over from the heat of anticipation. Last-minute meetings to ensure all was well filled restless hours as the world prepared to focus on the dramatic rover landings.

While the rovers were getting their "land legs," Stroupe was getting used to working in an oversized sandbox. Deep in the corners of an aging building that was part of the original bones of JPL, toddler robots train for possible future missions. Intended to precede humans to Mars, these petite teams carry and integrate structural components, simulating remote habitat building.

"We want to send robots ahead of astronauts to build a safe habitat that's already there when they arrive," said Stroupe. "Especially for Mars, if you have to wait six months for a rescue, you want to make sure it's safe when you go."

Giving robots the ability to build habitats and search for resources takes work. Rovers need a very specific set of instructions. "A robot doesn't make assumptions," Stroupe explained. "The real challenge is figuring out how to translate what we want it to do into step-by-step instructions, then run the commands and see what it does. It's what I imagine it would be like to watch a child take its first step or go off to school. You get personal satisfaction from having caused that."

From a JPL Sandbox to Mars

As the promise of the two veteran rover explorers on Mars grew, Earthlings who worked on the project were called to work on different missions. Just a few hundred feet down the road from the sandbox in a nondescript eight-story building, Stroupe switched from prototypes to actual rovers on Mars.

Initially, Stroupe was among a team of experts who interpreted data sent back by the rovers - analyzing the machines' movements and activities. When still more engineers moved on to other projects, the mission team began to recruit new drivers; experience driving on Mars wasn't necessary - training would be provided. Stroupe was accepted and driving school began.

Getting Your Rover Driver's License

As with any driver's education class, you don't just hop into the driver's seat at JPL. Stroupe shadowed a team of eight expert rover drivers. Like responsible parents, skilled drivers hand down knowledge to the newbies, including certain tricks and styles suited to the distinct personalities and unique environments of each rover.

"It's like trying to drive a car by writing a computer program," Stroupe said. "We have to tell it to turn a certain amount, drive a defined distance, take a picture or use its autonavigation function that allows it to reach goals on its own - all while ensuring its safety."

Training with robotics experts at Carnegie Mellon University, Stroupe was well prepared to take on the hefty job of handling the rovers. Still, realizing the enormity of actually controlling a rover on Mars is nothing less than awe-inspiring to her.

It Takes a Team to Raise a Robot

When someone casually mentioned to her that she was the first woman to drive a rover on Mars, it came as a surprise to Stroupe. After all, nearly half of the rover team is made up of women. Still, the title makes her proud and she hopes it will be inspiring to other people who want to be "firsts" in their fields.

"The most personal satisfaction is getting to work with these rovers and this incredible team. You can't do a project with just one or two people. It's such a rare opportunity for me as an engineer to work with scientists and engineers and feel like I'm making a real, significant contribution to forwarding science and our understanding of our solar system and universe. It's incredibly rewarding," she beamed. "And whether anybody ever knows my name or not, they'll see my [rover] tracks - I guess I have made my mark on Mars!"
 
Desert Find Lends More Strength to Theories of Possible Life on Mars



A University of Arkansas researcher has found methane-producing microorganisms in an unexpected place - arid desert soils. This finding strengthens the possibility that such microorganisms can exist under the conditions found on Mars and points the way to possible future experiments for detection of life on a distant planet.

Tim Kral, professor of biological sciences in the J. William Fulbright College of Arts and Sciences, along with researchers from the University of Southern California reported their findings online in the journal Icarus.

"You don't commonly find organisms such as methanogens in dry areas," said Kral. "But finding them in a dry area on Earth is especially significant because the surface of Mars is dry."

Researchers collected five vapor samples each from the Mars Desert Research Station in Utah and from the Idaho High Desert, as well as 40 soil samples from the Utah site, one from Death Valley, Calif., 19 from the Arctic Circle and one from the Atacama Desert in Chile. The samples were sent to Kral for analysis in his laboratory, where he has previously grown and monitored methanogens.

Examination of the vapor samples from the sites found that three of the five gas samples contained methane, indicating the possible presence of methanogens in the soil. In addition, five of the 40 soil samples from Utah produced methane when they were treated with a growth medium, again indicating the presence of methanogens.

Methanogens are found in anaerobic environments on Earth, from hot springs to the deep ocean to the intestinal tracts of humans and animals. Methanogens do not require oxygen to survive; instead, these tiny creatures breathe carbon dioxide and hydrogen gas, producing methane as a waste product. This unique form of respiration makes methanogens potentially viable residents of Mars, whose atmosphere is predominantly composed of carbon dioxide with practically no oxygen.

Methane, a gaseous compound of carbon and hydrogen, recently has been found in the atmosphere of Mars. Methane is unstable in the presence of ultraviolet sunlight and can be completely destroyed in the atmosphere in only a few hundred years. Its presence in the Martian atmosphere can only be explained if there is some process on Mars that is continually creating it.

Two potential scenarios could explain the presence of the gas, Kral said. Either the methane is being produced by living organisms, which would mean that some type of methanogens already inhabit the planet, or the methane is being made below the planet's surface by subsurface volcanic activity. The presence of such volcanic activity would mean that there is a source of energy and warmth below the surface -- two factors that are indicators that liquid water may also exist below the surface.

Finding methanogens in dry, arid climates shows that they may be able to exist in the limited water conditions found on Mars. The researchers suggest that collection methods used in the desert study could be modified for use in future biodetection experiments on Mars.

Source: University of Arkansas


http://www.physorg.com/news8513.html
 
Radar reveals ice deep below Martian surface

The first ever underground investigation of another planet has been performed by a radar antenna aboard Europe's Mars Express spacecraft. The instrument probed two kilometres below the Martian surface and found tantalising hints of liquid water pooling in a buried impact crater.

The MARSIS antenna was deployed successfully in June 2005 after a series of glitches. It works by sending radio pulses towards the Red Planet and then analysing the time delay and strength of the pulses that bounce back. The radio waves that penetrate the surface rebound when they encounter a sub-surface boundary between materials with different electrical properties - such as rock and water.

But aside from one Apollo 17 radar experiment on the Moon in 1972 - which yielded mixed results - the technique had never been tested.

"This is very experimental," says William T K Johnson, MARSIS manager at NASA's Jet Propulsion Laboratory in Pasadena, California, US. "We wondered - can we see anything in the subsurface? The answer to that is yes."

Ice bowl
Johnson and colleagues have now revealed subsurface measurements of two regions in the planet's northern hemisphere – the mid-latitude lowlands called Chryse Planitia and the northern polar cap.

They believe a 250-kilometre-wide circular structure that lies between 1.5 and 2.5 kilometres below the surface of Chryse Planitia is an impact crater that was buried with volcanic ash or soil several billion years ago. The team sees no radar boundaries in material that fills the bowl of the crater and the radar signals lose no strength when passing through it. That suggests the infill must contain a large proportion of ice, which is transparent to radar.

Substantial amounts of ice in the soil would make sense given the crater's location in what appears to be a basin where ancient rivers once converged. "If the water could be captured in a basin and preserved for several billion years, it may still be there," says MARSIS co-leader Jeff Plaut of NASA's Jet Propulsion Laboratory in Pasadena, California, US.

Intriguingly, the signal reflected from the bottom of the crater is so strong and appears so flat that it may be liquid water. "If you put water there, that's what the signal might look like," Johnson told New Scientist. But he cautions the data is based on only one pass over the region and could be caused by another material.

Rare pass
MARSIS also studied the northern polar cap and found what appear to be layered deposits of nearly pure water ice stretching down 1.8 kilometres below the surface, with an icy layer of sand underneath. These layers - which include varying amounts of dust - may reveal clues about the geologic processes that shaped Mars, says Johnson: "Maybe we have a history of Mars in how thick the layers are."

The researchers are encouraged that such interesting features have emerged from only three data-gathering passes. MARSIS has only been able to make this small number of observations because the results can only be obtained under special circumstances.

It can only study the subsurface when it is closest to Mars - just 26 minutes of each 7-hour orbit – and when it is also on the planet's "night" side. That is because energetic electrons in the sunlit portions of the planet's outer atmosphere, or ionosphere, block the radar's longest, ground-penetrating wavelengths.

For the last several months, these conditions have not existed at all. But, the conditions are now right again and will remain so until May 2006. The next study regions are in the southern hemisphere, including the south pole.

But gathering the data is only the first step – it then has to be interpreted, which can take scientists months. That is because radar signals travel at different speeds through the ionosphere depending on their wavelength, and the ionosphere itself varies in size depending on the Sun's activity.

"The ionosphere is always around pestering us," says Johnson. He adds that so far the ionosphere has prevented the instrument's longest wavelengths – which could reach down as far as five kilometres - from returning data.

http://www.newscientistspace.com/article.ns?id=dn8397
 
Buried craters and underground ice - Mars Express uncovers depths of Mars



For the first time in the history of planetary exploration, the MARSIS radar on board ESA's Mars Express has provided direct information about the deep subsurface of Mars. First data include buried impact craters, probing of layered deposits at the north pole and hints of the presence of deep underground water-ice.

Image: These MARSIS 'radargram' images show echoes obtained from an approximately 250 km diameter circular structure in the subsurface of Mars, interpreted to be a buried impact basin. In both orbits, which are spaced about 50 km apart, MARSIS detected a series of arc-shaped reflectors that have no apparent source in the surface topography or geology. In the lower image, a linear reflector nearly parallel to the surface is seen embedded in the arcs. This reflection may be coming from the floor of the basin. The time delay to the linear reflector suggests a depth of 1.5-2.5 km. Credits: ASI/NASA/ESA/Univ. of Rome/JPL

The subsurface of Mars has been so far unexplored territory. Only glimpses of the Martian depths could be deduced through analysis of impact crater and valley walls, and by drawing cross-sections of the crust deduced from geological mapping of the surface.

With measurements taken only for a few weeks during night-time observations last summer, MARSIS - the Mars Advanced Radar for Subsurface and Ionospheric Sounding - is already changing our perception of the Red Planet, adding to our knowledge the missing 'third' dimension: the Martian interior.

First results reveal an almost circular structure, about 250 km in diameter, shallowly buried under the surface of the northern lowlands of the Chryse Planitia region in the mid-latitudes on Mars. The scientists have interpreted it as a buried basin of impact origin, possibly containing a thick layer of water-ice-rich material.

To draw this first exciting picture of the subsurface, the MARSIS team studied the echoes of the radio waves emitted by the radar, which passed through the surface and then bounced back in the distinctive way that told the 'story' about the layers penetrated.

These echo structures form a distinctive collection that include parabolic arcs and an additional planar reflecting feature parallel to the ground, 160 km long. The parabolic arcs correspond to ring structures that could be interpreted as the rims of one or more buried impact basins. Other echoes show what may be rim-wall 'slump blocks' or 'peak-ring' features.

The planar reflection is consistent with a flat interface that separates the floor of the basin, situated at a depth of about 1.5 to 2.5 km, from a layer of overlying different material. In their analysis of this reflection, scientists do not exclude the intriguing possibility of a low-density, water-ice-rich material at least partially filling the basin.

"The detection of a large buried impact basin suggests that MARSIS data can be used to unveil a population of hidden impact craters in the northern lowlands and elsewhere on the planet," says Jeffrey Plaut, Co-Principal Investigator on MARSIS. "This may force us to reconsider our chronology of the formation and evolution of the surface."

MARSIS also probed the layered deposits that surround the north pole of Mars, in an area between 10º and 40º East longitude. The interior layers and the base of these deposits are poorly exposed. Prior interpretations could only be based on imaging, topographic measurements and other surface techniques.

Two strong and distinct echoes coming from the area correspond to a surface reflection and subsurface interface between two different materials. By analysis of the two echoes, the scientists were able to draw the likely scenario of a nearly pure, cold water-ice layer thicker than 1 km, overlying a deeper layer of basaltic regolith. This conclusion appears to rule out the hypothesis of a melt zone at the base of the northern layered deposits.


To date, the MARSIS team has not observed any convincing evidence for liquid water in the subsurface, but the search has only just begun. "MARSIS is already demonstrating the capability to detect structures and layers in the subsurface of Mars which are not detectable by other sensors, past or present," says Giovanni Picardi, MARSIS Principal Investigator.

"MARSIS holds exciting promise to address, and possibly solve, a number of open questions of major geological significance," he concluded.

These findings appear on line in Science, on 30 November 2005, in an article entitled 'Radar soundings of the subsurface of Mars'.

Source: ESA

http://www.physorg.com/news8588.html
 
Rover should 'target old rocks'


A French scientist believes Europe's next mission to Mars should target some of the oldest rocks on the planet if it wants to find evidence of past life.

Jean-Pierre Bibring has identified areas that were in contact with water just after the planet's formation.

In one such region, known as Marwth Vallis, conditions could have been stable long enough for life to start.

Prof Bibring is pushing for Europe's ExoMars rover, an 580m-euro robotic vehicle, to be sent there in 2011.

He said: "Marwth Vallis is a good site, too, because the altitude is close to zero.

"You have to have a site very low on Mars for the parachutes to work."

Persistent water

The scientist from the Institute of Space Astrophysics, Orsay, was speaking here at the Fall Meeting of the American Geophysical Union.

He made his remarks as Europe's space ministers gathered in Germany to approve the ExoMars rover. An official announcement signing off the project will be made on Tuesday.

ExoMars will carry a drill and a suite of instruments to study surface materials for evidence of past or present biology.

And when mission managers come to decide where to send the rover, they will be listening closely to Prof Bibring's views.

He is the principal investigator on Omega, an instrument on the Mars Express orbiter that is mapping the minerals in the Red Planet's surface rocks.

It can see materials that were formed over long time periods in the presence of large amounts of liquid water.

What is fascinating is that these hydrated minerals - so called because they contain water in their crystalline structure - were produced in the first few hundred million years after the planet was created. In other words, the rocks they make up are more than four billion years old.

Benign for life

Crucially, these are not the sulphate minerals seen by the US Mars rovers but a different class of hydrated minerals, known as phyllosilicates - more familiarly called clay minerals.

In Bibring's opinion, it is far more likely that ExoMars will find evidence of life laid down in these rocks than if it were to look at the sulphates documented by the US vehicles.

Phyllosilicates trace the moment when liquid water was perennial and persistent - something not necessary to make sulphates. To make clay minerals requires long-standing bodies of water and [for life to form] you need that - at least with the experience we have from Earth."

This puts Marwth Vallis and other clay locations - such as Arabia Terra, Terra Meridiani, Syrtis Major, and Nili Fossae - high on the list of possible ExoMars targets.

And it pushes down the list the sulphate locations such Meridiani Planum and Gusev Crater currently being inspected by the US Mars rovers. Their sulphates were formed in acidic conditions - a challenging environment for any lifeform to evolve.

It is a point echoed last week by US rover scientist Dr Andrew Knoll of Harvard University.

He observed: "Life that had evolved in other places or earlier times on Mars, if any did, might adapt to Meridiani conditions, but the kind of chemical reactions we think were important to giving rise to life on Earth simply could not have happened at Meridiani."

Jean-Pierre Bibring says the instruments on ExoMars should be equipped to look for large carbon molecules in amongst the clays of Marwth Vallis as a possible signature of past life.
http://news.bbc.co.uk/1/hi/sci/tech/4502018.stm
 
UK signs up to Euro Mars mission

The UK is to play a key role in Europe's next mission to Mars.

The government is to invest 108m euros (£73.2m) to give Britain a major share in building the robotic probe.

European Space Agency (Esa) member states approved funding for the ExoMars mission at the agency's minsterial meeting in Berlin.

The rover will explore the surface of the Red Planet, in search of traces of life, past and present.

The mission is a key milestone in the Aurora programme, Esa's vision to send spacecraft and eventually astronauts to the Moon and Mars.

'Improve understanding'

In the near-term, it focuses on robotic missions: ExoMars set for 2011, followed by an international Mars sample return mission.

Speaking at the ministerial meeting, science minister Lord Sainsbury said: "As a major contributor, the UK will have a leading role in this programme which is set to improve our understanding of Mars and the Solar System."

Ministers approved funding for the 2006-2011 phase of the Aurora programme on Tuesday.

The bulk of the money will be used to develop ExoMars, with the rest being used for basic research into future missions to the Moon and Mars.

The UK is contributing 101m euros (£68.5m) to ExoMars and 7m euros (£4.7m) to the core research activities out of a total subscription of around 750m euros (£508m).

This will give British industry a large share of the work, allowing them to build on the expertise gained during the ill-fated Beagle 2 mission.

Beagle was designed to search for signs of life on the Red Planet but it did not survive entry and landing on Mars on Christmas Day 2003.

David Parker, director of space science at the British National Space Centre, said the mission would build on the heritage of Beagle 2.

"Imagine a spacecraft landing on Mars using parachutes and airbags, maybe a rocket system of some sort," he told the BBC News website.

"Once it has landed it's going to allow a rover to drive out onto the surface.

"But it's not just going to explore over the surface because it will have a drill and other instruments that can actually probe beneath the surface for the first time, and that's what's really special in this mission."

Tough choices

Subscribing to the Aurora programme has meant difficult decisions on other areas of the UK space budget.

The UK has signed up to a new system to manage data from environmental satellites called Global Monitoring for Environment and Security (GMES).

But it is contributing only about 4% (8.9m euros/£6m) of the total Esa budget of 200m euros. The UK space lobby has called for far greater investment in GMES, requesting a 16% contribution to the total budget.

Nick Veck of the UK space trade association, UKISP, said it was a lost opportunity for British industry.

"It seems rather bizarre that the UK wishes to lead on climate change but has snubbed this important programme that would help," he told the BBC News website.

Mike Healy, director of Earth Observation, Navigation and Science, UK, at EADS Astrium said industry was very disappointed by the decision.

"I cannot understand how the UK can be championing the cause of climate change but is going in at a level that is not much more than Finland, Switzerland and Sweden," he said.

The UK is committing 374.3m euros (£254m) to Esa's science programme, representing about 18% of the total Esa science programme budget.

It is also investing 205m euros (£139m) to a series of earth observation missions. The first such satellite, the ice-monitoring probe, Cryosat, was lost on launch in October.

Sources close to the talks are confident Cryosat will be re-built but a final decision will not be made until February.

http://news.bbc.co.uk/1/hi/sci/tech/4503680.stm
 
Extreme bugs back idea of life on Mars
10:31 07 December 2005
NewScientist.com news service
Kelly Young and David L Chandler
Methane-producing microbes have been discovered in two extreme environments on Earth - buried under kilometres of ice in Greenland and living in hot, dry desert soil. The findings lend weight to the idea that similar organisms may have lived on Mars.

Live microbes making methane were found in a glacial ice core sample retrieved from three kilometres under Greenland by researchers from the University of California, Berkeley, US. It is the first time such archaea have been found at that depth, says Buford Price, one of the research team, which published its results in the Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.0507601102).

Scientists had already noticed that the concentrations of methane in the lowest 90 metres of the ice core was 10 times as high as that at other depths. Now the Berkeley scientists have found the likely cause - correspondingly higher levels of microbes that produce methane, known as methanogens.

Areas of high methane concentration in the Martian atmosphere have been spotted by Europe’s Mars Express spacecraft, but its origin is uncertain. A renewable source of methane would be needed, as otherwise ultraviolet light from the Sun would have destroyed it within 340 years. The methane could come from a geological source, such as unseen volcanic activity, or biological sources such as methanogens.

Poor-man’s borehole
Price’s group used the data from Greenland to devise a scenario on Mars, in order to guide future missions. The methanogens in the ice cores existed at -10°C, but could produce more methane in warmer conditions. In order to account for the methane seen on Mars, they calculated the bugs would have to live at 0°C or above.

This temperature is likely to occur between 150 metres and 8 kilometres beneath the Martian surface, depending on the rock type. It would then take between 15 years and 30,000 years for that methane to percolate up to the surface.

“In my opinion, there’s no way in my lifetime that NASA will find a way of drilling a borehole 150 metres deep [on Mars],” Price told New Scientist. “But the poor-man’s borehole is just looking at what’s been thrown out of a crater.”

So a spacecraft could be sent to a large crater where higher levels of atmospheric methane have been detected. The lander could then drill a shorter distance down into the crater to try to find evidence of life.

Desert dwellers
Another new study, reported in the journal Icarus (vol 178, p 277), has also discovered methanogens in a harsh environment on Earth. Researchers studied dozens of soil and vapour samples from five different desert environments in Utah, Idaho and California in the US, and in Canada and Chile.

Of these, five soil samples and three vapour samples from the vicinity of the Mars Desert Research Station in Utah were found to have signs of viable methanogens. The methane in the vapour samples was 300 times higher than background levels.

One of the team, Timothy Kral of the University of Arkansas, US, told New Scientist that dry conditions usually kill this type of microbe: "So finding them in a dry place is not what everyone would have expected."

Methanogens require anaerobic (oxygen-free) environments to survive, and most combine carbon dioxide and hydrogen to generate energy. Kral explains that their samples were collected from possible anaerobic settings such as dry-channel deposits 70 centimetres underground.

The surface of Mars is also very dry, so the finding helps support the idea that the methane detected there could be an indicator of current microbial activity.

The lesson for Mars, says Andrew Knoll, a biogeochemist at Harvard University, US, and a member of the Mars rover science team, is that methanogenesis may be possible there, but only when the right conditions of a limited-oxygen environment and availability of nutrients occur.

http://www.newscientistspace.com/article.ns?id=dn8428

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Weblinks
P Buford Price, University of California, Berkeley
http://www.physics.berkeley.edu/research/price/
Tim Kral, University of Arkansas
http://spacecenter.uark.edu/280.htm#[email protected]
Proceedings of the National Academy of Sciences
http://www.pnas.org
Icarus
http://icarus.cornell.edu/
 
Paving The Way For Women To Mars

When the first female astronauts set foot on Mars, they may spare a thought for the 24 women who paved the way for lengthy space trips by giving three months of their lives to space science, two months of which involved staying in bed.

From March to May and from September to November, two different groups of 12 volunteers from eight European countries - the Czech Republic, Finland, France, Germany, the Netherlands, Poland, Switzerland, and the United Kingdom - took part in the Women International Space Simulation for Exploration (WISE) campaign on behalf of the European Space Agency (ESA), the French space agency (CNES), the Canadian Space Agency (CSA) and the US National Aeronautics and Space Administration (NASA).

They gathered at the MEDES Space Clinic in Rangueil Hospital in Toulouse, France, to take up an extraordinary challenge: a 60-day campaign of female bedrest. For two months, they had to lie down and undertake all daily activities in beds tilted at an angle of 6 degrees below horizontal, so that their heads were slightly lower than their feet.

This unusual position induces physiological changes similar to those experienced by astronauts in weightlessness.

The last volunteers of the second WISE campaign got up on 30 November, and are now undergoing rehabilitation and medical tests lasting until 20 December. Similar tests were conducted in the pre-bedrest period for comparison.

MEDES, the French Institute for Space Medicine and Physiology, organised the selection of the volunteers and provided medical, paramedical and technical staff to support the extensive science experiments.

The main objective of the WISE campaign has been to assess the roles of nutrition and physical exercise with adapted equipment in countering the adverse effects of prolonged microgravity conditions, in order to develop the counter-measures that will be required when future astronauts venture beyond the Earth orbit to explore other worlds.

The data collected by the international science teams during the WISE study will improve our knowledge of muscle condition, blood parameters, cardiovascular condition, coordination of movements, changes in endocrine and immune systems, metabolism, bone status, as well as psychological wellbeing.

This will serve not only the future of human spaceflight, but our everyday lives on Earth too, by providing clues as to how to deal with osteoporosis, fight the ''metabolic syndrome", which affects millions of sedentary workers who take insufficient physical exercise, assist recovery of bedridden patients, or prevent some cardiovascular conditions.

Twelve scientific teams from 11 countries - Belgium, Canada, Denmark, France, Germany, Italy, the Netherlands, Sweden, Switzerland, the United Kingdom and the United States - are involved in the study. It will take them several months to analyse their data and start publishing their findings. In order to answer certain scientific questions, a follow-up of the volunteers will continue for three more years.

"The WISE campaign has now come to a successful conclusion and I look forward to further campaigns in the future where there is this degree of international involvement and complexity", said Didier Schmitt, Head of the Life Sciences Unit in ESA's Directorate of Human Spaceflight, Microgravity and Exploration.

"Planning for future research is already under way with a programme of bedrest campaigns being prepared, covering the next three years. This will be a combination of short-term, intermediate and long-term bedrest studies, lasting 5, 21 and 60 days, respectively.

A research announcement covering this period is due to be released in the near future as part of the European programme for Life and Physical Sciences and Applications using the ISS (ELIPS). A further two bedrest studies are planned, one in Berlin and the other at the DLR in Cologne and they have already been selected as part of the ESA Microgravity Applications Programme (MAP). These studies are currently awaiting the necessary funding, also from the ELIPS Programme."

To mark the completion of the WISE 2005 campaigns, ESA, CNES and MEDES are to hold a press conference, together with representatives from NASA and CSA, science teams and volunteers from the second WISE campaign, at the "Cité de l'Espace" in Toulouse on 13 December.

Source: ESA

http://www.physorg.com/news8958.html
 
Hundreds Of Auroras Detected On Mars


Auroras similar to Earth's Northern Lights appear to be common on Mars, according to physicists at the University of California, Berkeley, who have analyzed six years' worth of data from the Mars Global Surveyor.
The discovery of hundreds of auroras over the past six years comes as a surprise, since Mars does not have the global magnetic field that on Earth is the source of the aurora borealis and the antipodal aurora australis.

According to the physicists, the auroras on Mars aren't due to a planet-wide magnetic field, but instead are associated with patches of strong magnetic field in the crust, primarily in the southern hemisphere. And they probably aren't as colorful either, the researchers say: The energetic electrons that interact with molecules in the atmosphere to produce the glow probably generate only ultraviolet light - not the reds, greens and blues of Earth.

"The fact that we see auroras as often as we do is amazing," said UC Berkeley physicist David A. Brain, the lead author of a paper on the discovery recently accepted by the journal Geophysical Research Letters. "The discovery of auroras on Mars teaches us something about how and why they happen elsewhere in the solar system, including on Jupiter, Saturn, Uranus and Neptune."

Brain and Jasper S. Halekas, both assistant research physicists at UC Berkeley's Space Sciences Laboratory, along with their colleagues from UC Berkeley, the University of Michigan, NASA's Goddard Space Flight Center and the University of Toulouse in France, also reported their findings in a poster presented Friday, Dec. 9, at the American Geophysical Union meeting in San Francisco.

Last year, the European spacecraft Mars Express first detected a flash of ultraviolet light on the night side of Mars and an international team of astronomers identified it as an auroral flash in the June 9, 2005, issue of Nature. Upon hearing of the discovery, UC Berkeley researchers turned to data from the Mars Global Surveyor to see if an on-board UC Berkeley instrument package - a magnetometer-electron reflectometer - had detected other evidence of auroras.

The spacecraft has been orbiting Mars since September 1997 and since 1999 has been mapping from an altitude of 400 kilometers (250 miles) the Martian surface and Mars' magnetic fields. It sits in a polar orbit that keeps it always at 2 a.m. when on the night side of the planet.

Within an hour of first delving into the data, Brain and Halekas discovered evidence of an auroral flash - a peak in the electron energy spectrum identical to the peaks seen in spectra of Earth's atmosphere during an aurora. Since then, they have reviewed more than 6 million recordings by the electron reflectometer and found amid the data some 13,000 signals with an electron peak indicative of an aurora. According to Brain, this may represent hundreds of nightside auroral events like the flash seen by the Mars Express.

When the two physicists pinpointed the position of each observation, the auroras coincided precisely with the margins of the magnetized areas on the Martian surface. The same team, led by co-authors Mario H. Acuña of NASA's Goddard Space Flight Center and Robert Lin, UC Berkeley professor of physics and director of the Space Sciences Laboratory, has extensively mapped these surface magnetic fields using the magnetometer/reflectometer aboard the Mars Global Surveyor.

Just as Earth's auroras occur where the magnetic field lines dive into the surface at the north and south poles, Mars' auroras occur at the borders of magnetized areas where the field lines arc vertically into the crust.

Of the 13,000 auroral observations so far, the largest seem to coincide with increased solar wind activity.

"The flash seen by Mars Express seems to be at the bright end of energies that are possible," Halekas said. "Just as on Earth, space weather and solar storms tend to make the auroras brighter and stronger." Depiction of surface magnetic fields on Mars These are not boils on Mars, but a way of depicting the surface magnetic fields on the planet to emphasize their ability to shield the surface from the solar wind. The greater the bulge, the stronger and more protective the magnetic field. Note that most of the remaining magnetic fields are in the southern hemisphere. (Credit: David Brain/SSL)

Earth's auroras are caused when charged particles from the sun slam into the planet's protective magnetic field and, instead of penetrating to the ground, are diverted along field lines to the pole, where they funnel down and collide with atoms in the atmosphere to create an oval of light around each pole. Electrons are a big proportion of the charged particles, and auroral activity is associated with a physical process still not understood that accelerates electrons, producing a telltale peak in the spectrum of electron energies.

The process on Mars is probably similar, Lin said, in that solar wind particles are funneled around to the night side of Mars where they interact with crustal field lines. The ultraviolet light is produced when the particles hit carbon dioxide molecules.

"The observations suggest some acceleration process occurs like on Earth," he said. "Something has taken the electrons and given them a kick."

What that "something" is remains a mystery, though Lin and his UC Berkeley colleagues lean towards a process called magnetic reconnection, where the magnetic field traveling with the solar wind particles breaks and reconnects with the crustal field. The reconnecting field lines could be what flings the particles to higher energies.

The surface magnetic fields, Brain said, are produced by highly magnetized rock that occurs in patches up to 1,000 kilometers wide and 10 kilometers deep.

These patches probably retain magnetism left from when Mars had a global field in a way similar to what occurs when a needle is stroked with a magnet, inducing magnetization that remains even after the magnet is withdrawn. When Mars' global field died out billions of years ago, the solar wind was able to strip the atmosphere away. Only the strong crustal fields are still around to protect portions of the surface.

"We call them mini-magnetospheres, because they are strong enough to stand off the solar wind," Lin said, noting that the fields extend up to 1,300 kilometers above the surface. Nevertheless, the strongest Martian magnetic field is 50 times weaker than the field at the Earth's surface. It's hard to explain how these fields are able to funnel and accelerate the solar wind efficiently enough to generate an aurora, he said.

Brain, Halekas, Lin and their colleagues hope to mine the Mars Global Surveyor data for more information on the auroras and perhaps join with the European team operating the Mars Express to get complementary data on the flashes that could solve the mystery of their origin.

"Mars Global Surveyor was designed for a lifetime of 685 days, but it has been very valuable for more than six years now, and we are still getting great results," Lin observed.

The work was supported by NASA. Coauthors with Brain, Halekas, Lin and Acuña are Laura M. Peticolas, Janet G. Luhmann, David L. Mitchell and Greg T. Delory of UC Berkeley's Space Sciences Laboratory; Steve W. Bougher of the University of Michigan; and Henri Rème of the Centre d'Etude Spatiale des Rayonnements in Toulouse.

http://www.spacedaily.com/news/mars-atmosphere-05g.html
 
Microbes under Greenland Ice may be preview of what scientists find under Mars' surface



A University of California, Berkeley, study of methane-producing bacteria frozen at the bottom of Greenland's two-mile thick ice sheet could help guide scientists searching for similar bacterial life on Mars.

Methane is a greenhouse gas present in the atmospheres of both Earth and Mars. If a class of ancient microbes called Archaea are the source of Mars' methane, as some scientists have proposed, then unmanned probes to the Martian surface should look for them at depths where the temperature is about 10 degrees Celsius (18 degrees Fahrenheit) warmer than that found at the base of the Greenland ice sheet, according to UC Berkeley lead researcher P. Buford Price, a professor of physics.

This would be several hundred meters - some 1,000 feet - underground, where the temperature is slightly warmer than freezing and such microbes should average about one every cubic centimeter, or about 16 per cubic inch.

While Price is not expecting any time soon a mission to Mars to drill several hundred meters beneath the surface, methanogens (methane-generating Archaea) could just as easily be detected around meteor craters where rock has been thrown up from deep underground.

"Detecting this concentration of microbes is within the ability of state-of-the-art instruments, if they could be flown to Mars and if the lander could drop down at a place where Mars orbiters have found the methane concentration highest," Price said. "There are oodles of craters on Mars from meteorites and small asteroids colliding with Mars and churning up material from a suitable depth, so if you looked around the rim of a crater and scooped up some dirt, you might find them if you land where the methane oozing out of the interior is highest."

Price and his colleagues published their findings last week in the Early Online edition of the journal Proceedings of the National Academy of Sciences, and presented their results at last week's meeting of the American Geophysical Union in San Francisco.

Variations in methane concentration in ice cores, such as the 3,053-meter-long (10,016-foot-long) core obtained by the Greenland Ice Sheet Project 2, have been used to gauge past climate. In that core, however, some segments within about 100 meters, or 300 feet, of the bottom registered levels of methane as much as 10 times higher than would be expected from trends over the past 110,000 years.

Price and his colleagues showed in their paper that these anomalous peaks can be explained by the presence in the ice of methanogens. Methanogens are common on Earth in places devoid of oxygen, such as in the rumens of cows, and could easily have been scraped up by ice flowing over the swampy subglacial soil and incorporated into some of the bottom layers of ice.

Price and his colleagues found these methanogens in the same foot-thick segments of the core where the excess methane was measured in otherwise clear ice at depths 17, 35 and 100 meters (56, 115 and 328 feet) above bedrock. They calculated that the measured amount of Archaea, frozen and barely active, could have produced the observed amount of excess methane in the ice.

"We found methanogens at precisely those depths where excess methane had been found, and nowhere else," Price said. "I think everyone would agree that this is a smoking gun."

Biologists at Pennsylvania State University had earlier analyzed ice several meters above bedrock that was dark gray in appearance because of its high silt content, and identified dozens of types of both aerobic (oxygen-loving) and anaerobic (oxygen-phobic) microbes. They estimated that 80 percent of the microbes were still alive.

Though methane has been detected in Mars' atmosphere, ultraviolet light from the sun would have broken down the amount observed in about 300 years if some process was not replenishing the methane, Price noted. While interaction of carbon-bearing fluid with basaltic rock might be responsible, methanogens might instead take in subsurface hydrogen and carbon dioxide to make the methane, he said.

If methanogens are responsible, Price calculated that they would occur in a concentration of about one microbe per cubic centimeter at a depth of several hundred meters, where the temperature - about zero degrees Celsius (32 degrees Fahrenheit) or a bit warmer - would allow just enough metabolism for them to keep alive, just as the microbes in the Greenland ice sheet are doing.

Source: University of California - Berkeley


http://www.physorg.com/news9051.html
 
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