Topic: [Speculation] Mars, The Kevin Costner Friendly Planet

[SFC Bennie]

http://www.space.com/scienceastronomy/opportunity_evidence_040229.html

Mars: A Water World? Evidence Mounts, But Scientists Remain Tight-Lipped
By Leonard David
Senior Space Writer
posted: 01:00 pm ET
29 February 2004


PASADENA, California -- Evidence that suggests Mars was once a water-rich world is mounting as scientists scrutinize data from the Mars Exploration rover, Opportunity, busily at work in a small crater at Meridiani Planum. That information may well be leading to a biological bombshell of a finding that the red planet has been, and could well be now, an extraterrestrial home for life.

There is a palpable buzz here at the Jet Propulsion Laboratory (JPL) in Pasadena, California that something wonderful is about to happen in the exploration of Mars.

There is no doubt that the Opportunity Mars rover is relaying a mother lode of geological data. Using an array of tools carried by the golf cart-sized robot -- from spectrometers, a rock grinder, cameras and powerful microscopic imager -- scientists are carefully piecing together a compelling historical portrait of a wet and wild world.

Where Opportunity now roves, some scientists here suggest, could have been underneath a huge ocean or lake. But what has truly been uncovered by the robot at Meridiani Planum is under judicious and tight-lipped review.

Those findings and their implications are headed for a major press conference, rumored to occur early next week -- but given unanimity among rover scientists and agreement on how and who should unveil the dramatic findings. Turns out, even on Mars, a political and ego outcrop hangs over science.

Scientific bulls-eye
It is clear that Opportunity's Earth-to-Mars hole in one -- bouncing into a small crater complete with rock outcrop -- has also proven to be a scientific bulls-eye. The robot is wheeling about the crater that is some 70 feet (22 meters) across and 10 feet (3 meters) deep.

It is also apparent that there is a backlog of scientific measurements that Mars rover scientists working Opportunity have pocketed and kept close to their lab coats.

For one, the rover found the site laden with hematite -- a mineral that typically, but not always -- forms in the presence of water. Then there are the puzzling spherules found in the soil and embedded in rock. They too might be water-related, but also could be produced by the actions of a meteor impact or a spewing volcano.

A few spheres have been sliced in half and their insides imaged. Patches of these spherules, or "berries" as some call them, have undergone spectrometer exam to discern their mineral and chemistry makeup. Close-up photos of soil and rock have also shown thread-like features and even an oddly shaped object that looks like Rotini pasta.

Brew of dissolved salts
There is speculation that the soil underneath the wheels of both Spirit and Opportunity rovers contains small amounts of water mixed with salt in a brine. That brew of dissolved salts keeps the mixture well below the freezing point of pure water, permitting it to exist in liquid form.

Opportunity has revisited select spots in the outcrop, drawn there, in part, to look for cross-beds -- sedimentary deposits that are formed in beach, river and sand-dune environments. Using its Rock Abrasion Tool (RAT), the rover has carried out several cleaning and grinding sessions on exposed rock outcrop.

Cross-beds are patterns of curving lines or traces found within the strata of sandstone and other sedimentary rocks. Cross-bedding indicates the general direction and force of the wind or water that originally laid down the sediments.

Right around the corner
Opportunity's research is a "work in progress", said Ray Arvidson, deputy principal investigator for the Mars Exploration Rover (MER) project from Washington University in St. Louis. Data is being gathered to present "a coherent story", he said during a press briefing last Thursday.

"That story is right around the corner," Arvidson told SPACE.com . "But we need to finish this work in progress, finish the set of experiments, get the data down from the spacecraft, processed and analyzed. Then I think that the story will be known," he said.

Arvidson said multiple working hypotheses are still at play. Water is involved, but only on some of the hypotheses. Until coordinated experiments on the outcrop are completed, what the right hypothesis is remains unknown, he added.

Severing the umbilical cord
Mars exploration using the rovers has allowed on-the-spot "discovery driven science", said MER Deputy Project Scientist Albert Haldeman. He likened the Mars robot work now underway to deep ocean research using remotely operated submersibles.

"It turns out that the best way to explore rocks [on Mars] is go look at craters. Mobility buys us the ability to do that. It was the right fit for looking at rocks," Haldeman told SPACE.com . "The discovery from the Microscopic Imager and seeing those spherules?and finding a larger population of spherules and seeing them in the rocks and the outcrop?that progression of discovery influences our thinking."

Haldeman said the next step will be severing the umbilical cord between Opportunity and the crater it's exploring. The robot would wheel itself out of that site and onto the expansive terrain of Meridiani Planum.

"That umbilical cord?that's hard to break. It's more than even just a tension within the science team," Haldeman said.

Tantalizing hints
Scientists are carefully analyzing the rock data gleaned by the Opportunity rover. "We really want to understand that we've got those figured out right," Haldeman said. Up to now they have offered some "tantalizing hints", he said, that speak to a possible relationship with water.

Piecing together the story of what Opportunity has found involves great care and deliberation, Haldeman said, based on a wide-range of viewpoints and levels of expertise. "We want to be cautious," he explained.

More to the point, the science output from Mars must withstand scrutiny by experts outside the rover investigation teams.

"There are lots of geologists out there who are looking at these pictures and they are starting to drool," Haldeman said. "The American taxpayer that spent $800 million on this deserves a thorough analysis," Haldeman said.

Slippery slope leading to life
One scientist eagerly awaiting the news from Mars, particularly from Opportunity, is Gilbert Levin. He is Chairman of the Board and Executive Officer for Science of Spherix Incorporated in Beltsville, Maryland.

Levin is a former Viking Mars lander investigator. He has long argued that his 1976 Viking Labeled Release (LR) life detection experiment found living microorganisms in the soil of Mars.

In 1997, Levin reported that simple laws of physics require water to occur as a liquid on the surface of Mars. Subsequent experiments and research have bolstered this view, he said, and reaffirms his Viking LR data regarding microbial life on Mars.

Levin detailed his Mars views in a SPACE.com phone interview and via email.

"It's hard to image why such bullet-proof evidence was denied for such a long time, and why those so vigorously denying it never did so by meeting the science, but merely by brushing it away," Levin said.

"Of course, now that it must be acknowledged by all that there is liquid water on the surface of Mars," Levin added, "this starts those denying the validity of the Mars LR data down the slippery slope leading to life."

Mars mud
Levin points to Opportunity imagery that offers conclusive proof of standing liquid water and running water on a cold Mars.

Other images show the rover tracks clearly are being made in "mud", with water being pressed out of that material, Levin said. "That water promptly freezes and you can see reflecting ice. That's clearly ice. It could be nothing else," he said, "and the source is the water that came out of the mud."

As for the spherical objects found at the Opportunity site, Levin has a thought.

"I wonder on Mars if it can rain upwards," he said. The idea is that subsurface water comes up through the soils and then freezes when it gets to the surface.

"Maybe these little spherules form just like raindrops form up above," Levin explained.

Levin said that brine on Mars is a code word for liquid water. He senses that great care is being taken by rover scientists because the liquid water issue starts the road to life.

"That's the monument that they are afraid to erect without real due process," Levin concluded.  

[Flasheyes]

add this to the mystery...

NASA's Opportunity rover sent back new images from Mars showing that small spheres previously found on the surface also exist below, in a trench the rover dug. Hints of salty water were also found in the trench, but much more analysis is needed to learn the true composition.

Meanwhile Opportunity's twin rover, Spirit, is about to dig a trench of its own in order to investigate soil that sticks to its wheels, suggesting the fine-grained material might be moist.  
 
     Images
 
 

 
Opportunity made this close-up images of spherules embedded in the wall of a trench it dug with one wheel. These spheres are more reflective than those previously found on the Martian surface.
 
 
 
 
 

 
Opportunity's microscopic imager shows the partial 'clodding' or cementation of sand-sized grains within a trench wall. This image represents an area about 1.2 in. (3 cm) across.
 
 
 
 
     More Stories
 
 
 Rover Opportunity Digs in on Mars

 
 
 
 
 Opportunity to Burrow Under Martian Surface

 
 
 
 
 New Insight into Martian Winds

 
 
 
 
 Mystery Continues: Scientists Baffled by Spheres on Mars

 
 
 
 
 Mars Rovers Update: Opportunity Has Power Problems

 
 
 

 

In a press conference today, officials said the soil at both locations could contain small amounts of water mixed with salt in a brine that can exist in liquid form at very low temperatures.

The scientists stressed that only miniscule amounts of water would be needed to create the brine.

Water is the main thing scientists are searching for at Mars, because all life as we know it requires liquid water.

Mechanically speaking, both rovers are performing better than engineers promised and they might last into summer, well beyond the 90 days they were designed for, said Steven Squyres, principal investigator for the Mars Exploration Rover (MER) project from Cornell University.

Mission officials have long known that if all goes well, the rovers would indeed exceed the three-month life span that was considered a minimum design criteria. The robots face a host of threats, from frigid temperatures to high doses of radiation and wind-blown dust that can coat their solar panels, eliminating their source of power.

"These vehicles are holding up spectacularly," Squyres said today. But he cautioned that "projections are very difficult to make." Still, he said all signs point to a lifetime "that could be considerably longer" than the original plan and that he hoped to be still doing rover science in the summer.

Opportunity's spheres

At Meridiani Planum near the equator of Mars, Opportunity has examined its self-dug trench. More data is yet to be returned that should help scientists understand mysterious BB-sized spheres they've found strewn on the surface everywhere in the vicinity and embedded in a rock wall.

Now those spheres have been found in the trench.

Unlike those on the surface, the spheres in the wall of the trench are "polished and shiny," said geochemist Albert Yen of NASA?s Jet Propulsion Laboratory. No one knows why.

Yen said it's not surprising that the buried spheres are different from those at the surface, since they experience different conditions. Some coating could be responsible for the higher reflectivity of the long-buried spheres below. He said it was not due to just an effect of lighting.

In the broader sense, the spheres could have been formed in a volcano or a meteor impact, or they might be the result of running water. Those are the three hypothesis researchers have been working with for several days now. Each is still a possibility.

Spirit's travels

On the other side of Mars, Spirit has begun to encounter rocks ejected from a modest impact crater toward which it is headed. The rocks could prove interesting as a way to study the interior of Mars, explained Dave Des Marais of NASA's Ames Research Center.

The destination, called Bonneville crater, was carved out long ago by a space rock impact. Computer models show that rocks would have been carved from the crater in a reverse manner, the lower stuff being tossed higher and farther from the crater. Des Marais described it as similar to a flower opening.

"A lot of the older, deeper material gets thrown out farther," he said.

Spirit is starting to see rocks that could be those older ones. Finding out for sure will take weeks, in a two-pronged effort. Spirit will catalogue the compositions and colors of several rocks along the way. Then when it reaches the crater, scientists hope to see some exposed layers in the crater wall, then match their colors up with the tossed-out rocks.

"This is a bit of a wish," Des Marais said, "but I think it's a real possibility."

First, however, scientists want to study fine-grained soil that's sticking to Spirit's wheels. The rover will dig a trench to see whether the slightly cemented stuff exists below or is a surface phenomenon.

Des Marais said the material could be stuck together by a process where water and salt collect at the surface and form a cement. The salt is drawn upward in a continual process. Then the water evaporates, leaving the salt behind. If that is what's going on, then there should be more salt at the surface than below.

The trench is not expected to become a well, however.

"I wouldn't expect to see a pool of water," he said.

 http://www.space.com/missionlaunches/rover_update_040219.html    

[SFC Bennie]

http://www.space.com/scienceastronomy/opportunity_evidence_040229.html

Mars: A Water World? Evidence Mounts, But Scientists Remain Tight-Lipped
By Leonard David
Senior Space Writer
posted: 01:00 pm ET
29 February 2004


PASADENA, California -- Evidence that suggests Mars was once a water-rich world is mounting as scientists scrutinize data from the Mars Exploration rover, Opportunity, busily at work in a small crater at Meridiani Planum. That information may well be leading to a biological bombshell of a finding that the red planet has been, and could well be now, an extraterrestrial home for life.

There is a palpable buzz here at the Jet Propulsion Laboratory (JPL) in Pasadena, California that something wonderful is about to happen in the exploration of Mars.

There is no doubt that the Opportunity Mars rover is relaying a mother lode of geological data. Using an array of tools carried by the golf cart-sized robot -- from spectrometers, a rock grinder, cameras and powerful microscopic imager -- scientists are carefully piecing together a compelling historical portrait of a wet and wild world.

Where Opportunity now roves, some scientists here suggest, could have been underneath a huge ocean or lake. But what has truly been uncovered by the robot at Meridiani Planum is under judicious and tight-lipped review.

Those findings and their implications are headed for a major press conference, rumored to occur early next week -- but given unanimity among rover scientists and agreement on how and who should unveil the dramatic findings. Turns out, even on Mars, a political and ego outcrop hangs over science.

Scientific bulls-eye
It is clear that Opportunity's Earth-to-Mars hole in one -- bouncing into a small crater complete with rock outcrop -- has also proven to be a scientific bulls-eye. The robot is wheeling about the crater that is some 70 feet (22 meters) across and 10 feet (3 meters) deep.

It is also apparent that there is a backlog of scientific measurements that Mars rover scientists working Opportunity have pocketed and kept close to their lab coats.

For one, the rover found the site laden with hematite -- a mineral that typically, but not always -- forms in the presence of water. Then there are the puzzling spherules found in the soil and embedded in rock. They too might be water-related, but also could be produced by the actions of a meteor impact or a spewing volcano.

A few spheres have been sliced in half and their insides imaged. Patches of these spherules, or "berries" as some call them, have undergone spectrometer exam to discern their mineral and chemistry makeup. Close-up photos of soil and rock have also shown thread-like features and even an oddly shaped object that looks like Rotini pasta.

Brew of dissolved salts
There is speculation that the soil underneath the wheels of both Spirit and Opportunity rovers contains small amounts of water mixed with salt in a brine. That brew of dissolved salts keeps the mixture well below the freezing point of pure water, permitting it to exist in liquid form.

Opportunity has revisited select spots in the outcrop, drawn there, in part, to look for cross-beds -- sedimentary deposits that are formed in beach, river and sand-dune environments. Using its Rock Abrasion Tool (RAT), the rover has carried out several cleaning and grinding sessions on exposed rock outcrop.

Cross-beds are patterns of curving lines or traces found within the strata of sandstone and other sedimentary rocks. Cross-bedding indicates the general direction and force of the wind or water that originally laid down the sediments.

Right around the corner
Opportunity's research is a "work in progress", said Ray Arvidson, deputy principal investigator for the Mars Exploration Rover (MER) project from Washington University in St. Louis. Data is being gathered to present "a coherent story", he said during a press briefing last Thursday.

"That story is right around the corner," Arvidson told SPACE.com . "But we need to finish this work in progress, finish the set of experiments, get the data down from the spacecraft, processed and analyzed. Then I think that the story will be known," he said.

Arvidson said multiple working hypotheses are still at play. Water is involved, but only on some of the hypotheses. Until coordinated experiments on the outcrop are completed, what the right hypothesis is remains unknown, he added.

Severing the umbilical cord
Mars exploration using the rovers has allowed on-the-spot "discovery driven science", said MER Deputy Project Scientist Albert Haldeman. He likened the Mars robot work now underway to deep ocean research using remotely operated submersibles.

"It turns out that the best way to explore rocks [on Mars] is go look at craters. Mobility buys us the ability to do that. It was the right fit for looking at rocks," Haldeman told SPACE.com . "The discovery from the Microscopic Imager and seeing those spherules?and finding a larger population of spherules and seeing them in the rocks and the outcrop?that progression of discovery influences our thinking."

Haldeman said the next step will be severing the umbilical cord between Opportunity and the crater it's exploring. The robot would wheel itself out of that site and onto the expansive terrain of Meridiani Planum.

"That umbilical cord?that's hard to break. It's more than even just a tension within the science team," Haldeman said.

Tantalizing hints
Scientists are carefully analyzing the rock data gleaned by the Opportunity rover. "We really want to understand that we've got those figured out right," Haldeman said. Up to now they have offered some "tantalizing hints", he said, that speak to a possible relationship with water.

Piecing together the story of what Opportunity has found involves great care and deliberation, Haldeman said, based on a wide-range of viewpoints and levels of expertise. "We want to be cautious," he explained.

More to the point, the science output from Mars must withstand scrutiny by experts outside the rover investigation teams.

"There are lots of geologists out there who are looking at these pictures and they are starting to drool," Haldeman said. "The American taxpayer that spent $800 million on this deserves a thorough analysis," Haldeman said.

Slippery slope leading to life
One scientist eagerly awaiting the news from Mars, particularly from Opportunity, is Gilbert Levin. He is Chairman of the Board and Executive Officer for Science of Spherix Incorporated in Beltsville, Maryland.

Levin is a former Viking Mars lander investigator. He has long argued that his 1976 Viking Labeled Release (LR) life detection experiment found living microorganisms in the soil of Mars.

In 1997, Levin reported that simple laws of physics require water to occur as a liquid on the surface of Mars. Subsequent experiments and research have bolstered this view, he said, and reaffirms his Viking LR data regarding microbial life on Mars.

Levin detailed his Mars views in a SPACE.com phone interview and via email.

"It's hard to image why such bullet-proof evidence was denied for such a long time, and why those so vigorously denying it never did so by meeting the science, but merely by brushing it away," Levin said.

"Of course, now that it must be acknowledged by all that there is liquid water on the surface of Mars," Levin added, "this starts those denying the validity of the Mars LR data down the slippery slope leading to life."

Mars mud
Levin points to Opportunity imagery that offers conclusive proof of standing liquid water and running water on a cold Mars.

Other images show the rover tracks clearly are being made in "mud", with water being pressed out of that material, Levin said. "That water promptly freezes and you can see reflecting ice. That's clearly ice. It could be nothing else," he said, "and the source is the water that came out of the mud."

As for the spherical objects found at the Opportunity site, Levin has a thought.

"I wonder on Mars if it can rain upwards," he said. The idea is that subsurface water comes up through the soils and then freezes when it gets to the surface.

"Maybe these little spherules form just like raindrops form up above," Levin explained.

Levin said that brine on Mars is a code word for liquid water. He senses that great care is being taken by rover scientists because the liquid water issue starts the road to life.

"That's the monument that they are afraid to erect without real due process," Levin concluded.  

[Flasheyes]

add this to the mystery...

NASA's Opportunity rover sent back new images from Mars showing that small spheres previously found on the surface also exist below, in a trench the rover dug. Hints of salty water were also found in the trench, but much more analysis is needed to learn the true composition.

Meanwhile Opportunity's twin rover, Spirit, is about to dig a trench of its own in order to investigate soil that sticks to its wheels, suggesting the fine-grained material might be moist.  
 
     Images
 
 

 
Opportunity made this close-up images of spherules embedded in the wall of a trench it dug with one wheel. These spheres are more reflective than those previously found on the Martian surface.
 
 
 
 
 

 
Opportunity's microscopic imager shows the partial 'clodding' or cementation of sand-sized grains within a trench wall. This image represents an area about 1.2 in. (3 cm) across.
 
 
 
 
     More Stories
 
 
 Rover Opportunity Digs in on Mars

 
 
 
 
 Opportunity to Burrow Under Martian Surface

 
 
 
 
 New Insight into Martian Winds

 
 
 
 
 Mystery Continues: Scientists Baffled by Spheres on Mars

 
 
 
 
 Mars Rovers Update: Opportunity Has Power Problems

 
 
 

 

In a press conference today, officials said the soil at both locations could contain small amounts of water mixed with salt in a brine that can exist in liquid form at very low temperatures.

The scientists stressed that only miniscule amounts of water would be needed to create the brine.

Water is the main thing scientists are searching for at Mars, because all life as we know it requires liquid water.

Mechanically speaking, both rovers are performing better than engineers promised and they might last into summer, well beyond the 90 days they were designed for, said Steven Squyres, principal investigator for the Mars Exploration Rover (MER) project from Cornell University.

Mission officials have long known that if all goes well, the rovers would indeed exceed the three-month life span that was considered a minimum design criteria. The robots face a host of threats, from frigid temperatures to high doses of radiation and wind-blown dust that can coat their solar panels, eliminating their source of power.

"These vehicles are holding up spectacularly," Squyres said today. But he cautioned that "projections are very difficult to make." Still, he said all signs point to a lifetime "that could be considerably longer" than the original plan and that he hoped to be still doing rover science in the summer.

Opportunity's spheres

At Meridiani Planum near the equator of Mars, Opportunity has examined its self-dug trench. More data is yet to be returned that should help scientists understand mysterious BB-sized spheres they've found strewn on the surface everywhere in the vicinity and embedded in a rock wall.

Now those spheres have been found in the trench.

Unlike those on the surface, the spheres in the wall of the trench are "polished and shiny," said geochemist Albert Yen of NASA?s Jet Propulsion Laboratory. No one knows why.

Yen said it's not surprising that the buried spheres are different from those at the surface, since they experience different conditions. Some coating could be responsible for the higher reflectivity of the long-buried spheres below. He said it was not due to just an effect of lighting.

In the broader sense, the spheres could have been formed in a volcano or a meteor impact, or they might be the result of running water. Those are the three hypothesis researchers have been working with for several days now. Each is still a possibility.

Spirit's travels

On the other side of Mars, Spirit has begun to encounter rocks ejected from a modest impact crater toward which it is headed. The rocks could prove interesting as a way to study the interior of Mars, explained Dave Des Marais of NASA's Ames Research Center.

The destination, called Bonneville crater, was carved out long ago by a space rock impact. Computer models show that rocks would have been carved from the crater in a reverse manner, the lower stuff being tossed higher and farther from the crater. Des Marais described it as similar to a flower opening.

"A lot of the older, deeper material gets thrown out farther," he said.

Spirit is starting to see rocks that could be those older ones. Finding out for sure will take weeks, in a two-pronged effort. Spirit will catalogue the compositions and colors of several rocks along the way. Then when it reaches the crater, scientists hope to see some exposed layers in the crater wall, then match their colors up with the tossed-out rocks.

"This is a bit of a wish," Des Marais said, "but I think it's a real possibility."

First, however, scientists want to study fine-grained soil that's sticking to Spirit's wheels. The rover will dig a trench to see whether the slightly cemented stuff exists below or is a surface phenomenon.

Des Marais said the material could be stuck together by a process where water and salt collect at the surface and form a cement. The salt is drawn upward in a continual process. Then the water evaporates, leaving the salt behind. If that is what's going on, then there should be more salt at the surface than below.

The trench is not expected to become a well, however.

"I wouldn't expect to see a pool of water," he said.

 http://www.space.com/missionlaunches/rover_update_040219.html    

[SFC Bennie]

http://www.space.com/scienceastronomy/opportunity_evidence_040229.html

Mars: A Water World? Evidence Mounts, But Scientists Remain Tight-Lipped
By Leonard David
Senior Space Writer
posted: 01:00 pm ET
29 February 2004


PASADENA, California -- Evidence that suggests Mars was once a water-rich world is mounting as scientists scrutinize data from the Mars Exploration rover, Opportunity, busily at work in a small crater at Meridiani Planum. That information may well be leading to a biological bombshell of a finding that the red planet has been, and could well be now, an extraterrestrial home for life.

There is a palpable buzz here at the Jet Propulsion Laboratory (JPL) in Pasadena, California that something wonderful is about to happen in the exploration of Mars.

There is no doubt that the Opportunity Mars rover is relaying a mother lode of geological data. Using an array of tools carried by the golf cart-sized robot -- from spectrometers, a rock grinder, cameras and powerful microscopic imager -- scientists are carefully piecing together a compelling historical portrait of a wet and wild world.

Where Opportunity now roves, some scientists here suggest, could have been underneath a huge ocean or lake. But what has truly been uncovered by the robot at Meridiani Planum is under judicious and tight-lipped review.

Those findings and their implications are headed for a major press conference, rumored to occur early next week -- but given unanimity among rover scientists and agreement on how and who should unveil the dramatic findings. Turns out, even on Mars, a political and ego outcrop hangs over science.

Scientific bulls-eye
It is clear that Opportunity's Earth-to-Mars hole in one -- bouncing into a small crater complete with rock outcrop -- has also proven to be a scientific bulls-eye. The robot is wheeling about the crater that is some 70 feet (22 meters) across and 10 feet (3 meters) deep.

It is also apparent that there is a backlog of scientific measurements that Mars rover scientists working Opportunity have pocketed and kept close to their lab coats.

For one, the rover found the site laden with hematite -- a mineral that typically, but not always -- forms in the presence of water. Then there are the puzzling spherules found in the soil and embedded in rock. They too might be water-related, but also could be produced by the actions of a meteor impact or a spewing volcano.

A few spheres have been sliced in half and their insides imaged. Patches of these spherules, or "berries" as some call them, have undergone spectrometer exam to discern their mineral and chemistry makeup. Close-up photos of soil and rock have also shown thread-like features and even an oddly shaped object that looks like Rotini pasta.

Brew of dissolved salts
There is speculation that the soil underneath the wheels of both Spirit and Opportunity rovers contains small amounts of water mixed with salt in a brine. That brew of dissolved salts keeps the mixture well below the freezing point of pure water, permitting it to exist in liquid form.

Opportunity has revisited select spots in the outcrop, drawn there, in part, to look for cross-beds -- sedimentary deposits that are formed in beach, river and sand-dune environments. Using its Rock Abrasion Tool (RAT), the rover has carried out several cleaning and grinding sessions on exposed rock outcrop.

Cross-beds are patterns of curving lines or traces found within the strata of sandstone and other sedimentary rocks. Cross-bedding indicates the general direction and force of the wind or water that originally laid down the sediments.

Right around the corner
Opportunity's research is a "work in progress", said Ray Arvidson, deputy principal investigator for the Mars Exploration Rover (MER) project from Washington University in St. Louis. Data is being gathered to present "a coherent story", he said during a press briefing last Thursday.

"That story is right around the corner," Arvidson told SPACE.com . "But we need to finish this work in progress, finish the set of experiments, get the data down from the spacecraft, processed and analyzed. Then I think that the story will be known," he said.

Arvidson said multiple working hypotheses are still at play. Water is involved, but only on some of the hypotheses. Until coordinated experiments on the outcrop are completed, what the right hypothesis is remains unknown, he added.

Severing the umbilical cord
Mars exploration using the rovers has allowed on-the-spot "discovery driven science", said MER Deputy Project Scientist Albert Haldeman. He likened the Mars robot work now underway to deep ocean research using remotely operated submersibles.

"It turns out that the best way to explore rocks [on Mars] is go look at craters. Mobility buys us the ability to do that. It was the right fit for looking at rocks," Haldeman told SPACE.com . "The discovery from the Microscopic Imager and seeing those spherules?and finding a larger population of spherules and seeing them in the rocks and the outcrop?that progression of discovery influences our thinking."

Haldeman said the next step will be severing the umbilical cord between Opportunity and the crater it's exploring. The robot would wheel itself out of that site and onto the expansive terrain of Meridiani Planum.

"That umbilical cord?that's hard to break. It's more than even just a tension within the science team," Haldeman said.

Tantalizing hints
Scientists are carefully analyzing the rock data gleaned by the Opportunity rover. "We really want to understand that we've got those figured out right," Haldeman said. Up to now they have offered some "tantalizing hints", he said, that speak to a possible relationship with water.

Piecing together the story of what Opportunity has found involves great care and deliberation, Haldeman said, based on a wide-range of viewpoints and levels of expertise. "We want to be cautious," he explained.

More to the point, the science output from Mars must withstand scrutiny by experts outside the rover investigation teams.

"There are lots of geologists out there who are looking at these pictures and they are starting to drool," Haldeman said. "The American taxpayer that spent $800 million on this deserves a thorough analysis," Haldeman said.

Slippery slope leading to life
One scientist eagerly awaiting the news from Mars, particularly from Opportunity, is Gilbert Levin. He is Chairman of the Board and Executive Officer for Science of Spherix Incorporated in Beltsville, Maryland.

Levin is a former Viking Mars lander investigator. He has long argued that his 1976 Viking Labeled Release (LR) life detection experiment found living microorganisms in the soil of Mars.

In 1997, Levin reported that simple laws of physics require water to occur as a liquid on the surface of Mars. Subsequent experiments and research have bolstered this view, he said, and reaffirms his Viking LR data regarding microbial life on Mars.

Levin detailed his Mars views in a SPACE.com phone interview and via email.

"It's hard to image why such bullet-proof evidence was denied for such a long time, and why those so vigorously denying it never did so by meeting the science, but merely by brushing it away," Levin said.

"Of course, now that it must be acknowledged by all that there is liquid water on the surface of Mars," Levin added, "this starts those denying the validity of the Mars LR data down the slippery slope leading to life."

Mars mud
Levin points to Opportunity imagery that offers conclusive proof of standing liquid water and running water on a cold Mars.

Other images show the rover tracks clearly are being made in "mud", with water being pressed out of that material, Levin said. "That water promptly freezes and you can see reflecting ice. That's clearly ice. It could be nothing else," he said, "and the source is the water that came out of the mud."

As for the spherical objects found at the Opportunity site, Levin has a thought.

"I wonder on Mars if it can rain upwards," he said. The idea is that subsurface water comes up through the soils and then freezes when it gets to the surface.

"Maybe these little spherules form just like raindrops form up above," Levin explained.

Levin said that brine on Mars is a code word for liquid water. He senses that great care is being taken by rover scientists because the liquid water issue starts the road to life.

"That's the monument that they are afraid to erect without real due process," Levin concluded.  

[Flasheyes]

add this to the mystery...

NASA's Opportunity rover sent back new images from Mars showing that small spheres previously found on the surface also exist below, in a trench the rover dug. Hints of salty water were also found in the trench, but much more analysis is needed to learn the true composition.

Meanwhile Opportunity's twin rover, Spirit, is about to dig a trench of its own in order to investigate soil that sticks to its wheels, suggesting the fine-grained material might be moist.  
 
     Images
 
 

 
Opportunity made this close-up images of spherules embedded in the wall of a trench it dug with one wheel. These spheres are more reflective than those previously found on the Martian surface.
 
 
 
 
 

 
Opportunity's microscopic imager shows the partial 'clodding' or cementation of sand-sized grains within a trench wall. This image represents an area about 1.2 in. (3 cm) across.
 
 
 
 
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 Mystery Continues: Scientists Baffled by Spheres on Mars

 
 
 
 
 Mars Rovers Update: Opportunity Has Power Problems

 
 
 

 

In a press conference today, officials said the soil at both locations could contain small amounts of water mixed with salt in a brine that can exist in liquid form at very low temperatures.

The scientists stressed that only miniscule amounts of water would be needed to create the brine.

Water is the main thing scientists are searching for at Mars, because all life as we know it requires liquid water.

Mechanically speaking, both rovers are performing better than engineers promised and they might last into summer, well beyond the 90 days they were designed for, said Steven Squyres, principal investigator for the Mars Exploration Rover (MER) project from Cornell University.

Mission officials have long known that if all goes well, the rovers would indeed exceed the three-month life span that was considered a minimum design criteria. The robots face a host of threats, from frigid temperatures to high doses of radiation and wind-blown dust that can coat their solar panels, eliminating their source of power.

"These vehicles are holding up spectacularly," Squyres said today. But he cautioned that "projections are very difficult to make." Still, he said all signs point to a lifetime "that could be considerably longer" than the original plan and that he hoped to be still doing rover science in the summer.

Opportunity's spheres

At Meridiani Planum near the equator of Mars, Opportunity has examined its self-dug trench. More data is yet to be returned that should help scientists understand mysterious BB-sized spheres they've found strewn on the surface everywhere in the vicinity and embedded in a rock wall.

Now those spheres have been found in the trench.

Unlike those on the surface, the spheres in the wall of the trench are "polished and shiny," said geochemist Albert Yen of NASA?s Jet Propulsion Laboratory. No one knows why.

Yen said it's not surprising that the buried spheres are different from those at the surface, since they experience different conditions. Some coating could be responsible for the higher reflectivity of the long-buried spheres below. He said it was not due to just an effect of lighting.

In the broader sense, the spheres could have been formed in a volcano or a meteor impact, or they might be the result of running water. Those are the three hypothesis researchers have been working with for several days now. Each is still a possibility.

Spirit's travels

On the other side of Mars, Spirit has begun to encounter rocks ejected from a modest impact crater toward which it is headed. The rocks could prove interesting as a way to study the interior of Mars, explained Dave Des Marais of NASA's Ames Research Center.

The destination, called Bonneville crater, was carved out long ago by a space rock impact. Computer models show that rocks would have been carved from the crater in a reverse manner, the lower stuff being tossed higher and farther from the crater. Des Marais described it as similar to a flower opening.

"A lot of the older, deeper material gets thrown out farther," he said.

Spirit is starting to see rocks that could be those older ones. Finding out for sure will take weeks, in a two-pronged effort. Spirit will catalogue the compositions and colors of several rocks along the way. Then when it reaches the crater, scientists hope to see some exposed layers in the crater wall, then match their colors up with the tossed-out rocks.

"This is a bit of a wish," Des Marais said, "but I think it's a real possibility."

First, however, scientists want to study fine-grained soil that's sticking to Spirit's wheels. The rover will dig a trench to see whether the slightly cemented stuff exists below or is a surface phenomenon.

Des Marais said the material could be stuck together by a process where water and salt collect at the surface and form a cement. The salt is drawn upward in a continual process. Then the water evaporates, leaving the salt behind. If that is what's going on, then there should be more salt at the surface than below.

The trench is not expected to become a well, however.

"I wouldn't expect to see a pool of water," he said.

 http://www.space.com/missionlaunches/rover_update_040219.html