Close Examination of Bedrock Reveals More Clues

Image credit: NASA/JPL
Scientists are excited to see new details of layered rocks in Opportunity Ledge. In previous panoramic camera images, geologists saw that some rocks in the outcrop had thin layers, and images sent to Earth on sol 17 (Feb. 10, 2004) now show that the thin layers are not always parallel to each other like lines on notebook paper. Instead, if you look closely at this image from an angle, you will notice that the lines converge and diverge at low angles. These unparallel lines give unparalleled clues that some “moving current” such as volcanic flow, wind, or water formed these rocks. These layers with converging and diverging lines are a significant discovery for scientists who are on route to rigorously test the water hypothesis. The main task for both rovers in coming weeks and months is to explore the areas around their landing sites for evidence in rocks and soils about whether those areas ever had environments that were watery and possibly suitable for sustaining life. This is a cropped image taken by Opportunity’s panoramic camera on sol 16 (Feb. 9, 2004).

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C.

Original Source: NASA/JPL

Both Rovers on the Move

Image credit: NASA/JPL
NASA’s Spirit rover has begun making some of its own driving decisions while its twin, Opportunity, is presenting scientists with decisions to make about studying small spheres embedded in bedrock, like berries in a muffin.

Both rovers are on the move. Late Sunday, Spirit drove about 6.4 meters (21 feet), passing right over the rock called “Adirondack,” where it had finished examining the rock’s interior revealed by successfully grinding away the surface. The drive tested the rover’s autonomous navigation ability for the first time on Mars.

“We’ve entered a new phase of the mission,” said Dr. Mark Maimone, rover mobility software engineer at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. When the rover is navigating itself, it gets a command telling it where to end up, and it evaluates the terrain with stereo imaging to choose the best way to get there. It must avoid any obstacles it identifies. This capability is expected to enable longer daily drives than depending on step-by-step navigation commands from Earth. Tonight, Spirit will be commanded to drive farther on a northeastward course toward a crater nicknamed “Bonneville.”

Over the weekend, Spirit drilled the first artificial hole in a rock on Mars. Its rock abrasion tool ground the surface off Adirondack in a patch 45.5 millimeters (1.8 inches) in diameter and 2.65 millimeters (0.1 inch) deep. Examination of the freshly exposed interior with the rover?s microscopic imager and other instruments confirmed that the rock is volcanic basalt.

Opportunity drove about 4 meters (13 feet) today. It moved to a second point in a counterclockwise survey of a rock outcrop called “Opportunity Ledge” along the inner wall of the rover’s landing-site crater. Pictures taken at the first point in that survey reveal gray spherules, or small spheres, within the layered rocks and also loose on the ground nearby.

NASA now knows the location of Opportunity’s landing site crater, which is 22 meters (72 feet) in diameter. Radio signals gave a preliminary location less than an hour after landing, and additional information from communications with NASA’s Mars Odyssey orbiter soon narrowed the estimate, said JPL’s Tim McElrath, deputy chief of the navigation team.

As Opportunity neared the ground, winds changed its course from eastbound to northbound, according to analysis of data recorded during the landing. “It’s as if the crater were attracting us somehow,” said JPL’s Dr. Andrew Johnson, engineer for a system that estimated the spacecraft’s horizontal motion during the landing. The spacecraft bounced 26 times and rolled about 200 meters (about 220 yards) before coming to rest inside the crater, whose outcrop represents a bonanza for geologists on the mission.

JPL geologist Dr. Tim Parker was able to correlate a few features on the horizon above the crater rim with features identified by Mars orbiters, and JPL imaging scientist Dr. Justin Maki identified the spacecraft’s jettisoned backshell and parachute in another Opportunity image showing the outlying plains.

As a clincher, a new image from Mars Global Surveyor’s camera shows the Opportunity lander as a bright feature in the crater. A dark feature near the lander may be the rover. “I won’t know if it’s really the rover until I take another picture after the rover moves,” said Dr. Michael Malin of Malin Space Science Systems, San Diego. He is a member of the rovers’ science team and principal investigator for the camera on Mars Global Surveyor.

Opportunity’s crater is at 1.95 degrees south latitude and 354.47 degrees east longitude, the opposite side of the planet from Spirit’s landing site at 14.57 degrees south latitude and 175.47 degrees east longitude.

The first outcrop rock Opportunity examined up close is finely-layered, buff-colored and in the process of being eroded by windblown sand. “Embedded in it like blueberries in a muffin are these little spherical grains,” said Dr. Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the rovers’ scientific instruments. Microscopic images show the gray spheres in various stages of being released from the rock.

“This is wild looking stuff,” Squyres said. “The rock is being eroded away and these spherical grains are dropping out.” The spheres may have formed when molten rock was sprayed into the air by a volcano or a meteor impact. Or, they may be concretions, or accumulated material, formed by minerals coming out of solution as water diffused through rock, he said.

The main task for both rovers in coming weeks and months is to explore the areas around their landing sites for evidence in rocks and soils about whether those areas ever had environments that were watery and possibly suitable for sustaining life.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University at http://athena.cornell.edu.

Original Source: NASA/JPL News Release

Opportunity Gets Rolling

Image credit: NASA/JPL
NASA’s Opportunity rover drove about 3.5 meters (11 feet) early Thursday toward a rock outcrop in the wall of a small crater on Mars, and mission controllers plan to send it the rest of the way to the outcrop late Thursday.

Opportunity’s twin, Spirit, successfully reformatted its flash memory on Wednesday. Flash is a type of rewritable memory used in many electronic devices, such as digital cameras, to retain information even while power is off. Problems with the flash memory interfered with Spirit’s operations from Jan. 22 until this week. Engineers prescribed the reformatting to prevent recurrence of the problem.

On Thursday, Spirit’s main assignment is to brush off an area on the rock nicknamed “Adirondack” to prepare for a dust-free examination of its surface. On Friday, controllers at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., plan to have Spirit grind off a small patch of Adirondack?s outer surface and inspect the rock’s interior. Spirit may start driving over the weekend toward a crater about 250 meters (about 270 yards) to the northeast.

For Opportunity, halfway around Mars from Spirit, controllers changed plans Thursday morning. They postponed a trenching operation until the rover gets to an area of its landing-site crater where the soil has a higher concentration of large- grain hematite. That mineral holds high interest because it usually forms under wet conditions. The main science goal for both rovers is to find geological clues about past environmental conditions at the landing sites, especially about whether conditions were ever watery and possibly suitable for sustaining life.

Instead of trenching, Opportunity will be commanded after it next wakes up to drive about 1.5 meters (about 5 feet) farther, possibly to within arm’s reach of one of the rocks in the exposed outcrop.

Before it began driving on Wednesday, Opportunity finished using its alpha particle X-ray spectrometer for the first time. This spectrometer, which assesses what chemical elements are present, took readings on an area of soil that the rover had previously examined with its microscope.

Each martian day, or “sol,” lasts about 40 minutes longer than an Earth day. Spirit begins its 34rd sol on Mars at 3:22 a.m. Thursday, Pacific Standard Time. Opportunity begins its 14th sol on Mars at 3:43 p.m. Friday, PST.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University, Ithaca, N.Y., at http://athena.cornell.edu.

Original Source: NASA/JPL News Release

Rover Sees Spheres in the Martian Soil

Image credit: NASA/JPL
NASA’s Opportunity has examined its first patch of soil in the small crater where the rover landed on Mars and found strikingly spherical pebbles among the mix of particles there.

“There are features in this soil unlike anything ever seen on Mars before,” said Dr. Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the science instruments on the two Mars Exploration Rovers.

For better understanding of the soil, mission controllers at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., plan to use Opportunity’s wheels later this week to scoop a trench to expose deeper material. One front wheel will rotate to dig the hole while the other five wheels hold still.

The spherical particles appear in new pictures from Opportunity’s microscopic imager, the last of 20 cameras to be used on the two rover missions. Other particles in the image have jagged shapes. “The variety of shapes and colors indicates we’re having particles brought in from a variety of sources,” said Dr. Ken Herkenhoff of the U.S. Geological Survey’s Astrogeology Team, Flagstaff, Ariz.

The shapes by themselves don’t reveal the particles’ origin with certainty. “A number of straightforward geological processes can yield round shapes,” said Dr. Hap McSween, a rover science team member from the University of Tennessee, Knoxville. They include accretion under water, but apparent pores in the particles make alternative possibilities of meteor impacts or volcanic eruptions more likely origins, he said.

A new mineral map of Opportunity’s surroundings, the first ever done from the surface of another planet, shows that concentrations of coarse-grained hematite vary in different parts of the crater. The soil patch in the new microscopic images is in an area low in hematite. The map shows higher hematite concentrations inside the crater in a layer above an outcrop of bedrock and on the slope just under the outcrop.

Hematite usually forms in association with liquid water, so it holds special interest for the scientists trying to determine whether the rover landing sites ever had watery environments possibly suitable for sustaining life. The map uses data from Opportunity’s miniature thermal emission spectrometer, which identifies rock types from a distance.

“We’re seeing little bits and pieces of this mystery, but we haven’t pieced all the clues together yet,” Squyres said.

Opportunity’s Moessbauer spectrometer, an instrument on the rover’s robotic arm designed to identify the types of iron- bearing minerals in a target, found a strong signal in the soil patch for olivine. Olivine is a common ingredient in volcanic rocks. A few days of analysis may be needed to discern whether any fainter signals are from hematite, said Dr. Franz Renz, science team member from the University of Mainz, Germany.

To get a better look at the hematite closer to the outcrop, Opportunity will go there. It will begin by driving about 3 meters (10 feet) tomorrow, taking it about halfway to the outcrop. On Friday it will dig a trench with one of its front wheels, said JPL’s Dr. Mark Adler, mission manager.

Opportunity’s twin, Spirit, today is reformatting its flash memory, a preventive measure that had been planned for earlier in the week. “We spent the last four days in the testbed testing this,” Adler said. “It’s not an operation we do lightly. We’ve got to be sure it works right.” Tomorrow, Spirit will resume examining a rock called Adirondack after a two-week interruption by computer memory problems. Controllers plan to tell Spirit to brush dust off of a rock and examine the cleaned surface tomorrow.

Each martian day, or “sol,” lasts about 40 minutes longer than an Earth day. Spirit begins its 33rd sol on Mars at 2:43 a.m. Thursday, Pacific Standard Time. Opportunity begins its 13th sol on Mars at 3:04 p.m. Thursday, PST.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University at http://athena.cornell.edu.

Original Source: NASA/JPL News Release

Can the Rovers Find Life on Mars?

Image credit: ESA
Astrobiology Magazine (AM): The first batch of images from Meridiani Planum, showing finely layered bedrock, have scientists pretty excited. What are your initial impressions?

Andrew Knoll (AK): We’ve known for several years, from orbital data, that there are layered rocks on Mars, but Opportunity gives us our first chance to actually go and work directly on some of these rocks in an outcrop. For geologists, you just can’t overemphasize the importance of that.

The fact that they’re sort of tabular suggests that they’re either fairly thin volcanic deposits or sediments. And the prospect of having in situ sedimentary rocks on Mars that we can go up and interrogate is about a best-case scenario, as far as I’m concerned.

AM: What if they turn out to be volcanic ash deposits? Will that make for a less interesting scenario?

AK: Not at all. I think one of the big questions is, What are the predominant processes that have given rise to layered rocks on Mars? There’s no reason to believe that every layered rock on Mars formed in the same way as the ones that Opportunity’s sitting in front of. But to know even how one of those layered rocks formed will be a step in the right direction.

We will also soon know whether the hematite signal in Meridiani that was detected from orbit is resident in those rocks. Remember the reason that we’re at Meridiani Planum is because of this strong signal for a particular form of iron oxide called hematite. It’s very difficult to think about making hematite without some liquid water interactions with rocks. So even if it’s a volcanic rock, it will help to constrain our thinking about one of the most interesting chemical anomalies on the planet.

AM: There’s a river in Spain, the Rio Tinto, where you’ve spent some time doing research. You’ve suggested that the way the iron minerals at Rio Tinto have degraded and transformed over time might shed some light on how the hematite at Meridiani formed. Can you explain the connection?

AK: Let me start at the beginning. The kinds of thinking we bring to the interpretation of iron on Mars will be informed by our experience with oxidized iron on the Earth’s surface. There are a number of ways that iron deposits have formed on our planet. It may be that no one of them is going to be an exact analog for what happened on Mars. But each of them might give tidbits of information that will help us think about Mars.

Now, Rio Tinto is a very interesting place. It’s in southwestern Spain, about an hour west of Seville, maybe another hour east of the Portuguese border. Rio Tinto is actually of historical interest to people in America since Columbus set sail in 1492 from a port at the mouth of the Rio Tinto. But it’s also of interest to mining geologists because it has been a mine at least since the time of the Romans.

What’s being mined there is iron ore. About 400 million years ago hydrothermal processes formed these iron ore deposits. Mostly the iron is in the form of iron sulfide, or fool’s gold. It’s very rich ore. As rainwater percolates down through these deposits, it oxidizes the pyrite and two things happen. One, it forms sulfuric acid. So the water in the river has a pH of about 1; it’s very acidic. And, two, the iron gets oxidized. So the water is about the color of rubies, because of this iron being carried around.

What’s interesting is that if you look at the deposits that are forming from the Rio Tinto today, most of the iron is coming out as iron sulfate minerals, that is, a combination of iron, sulfur and oxygen; and a little bit of it is coming out as a mineral called goethite, which is iron mixed with oxygen and a little bit of hydrogen. Goethite is basically rust.

That’s not what you see at Meridiani on Mars. But what’s interesting about the Rio Tinto deposit is that this process has been taking place for at least 2 million years. And there is a series of terraces that give us a sense of what happens to these deposits over time.

What we find is that after just a few thousand years, all of the sulfate minerals have disappeared and all of the iron is in this material called goethite. But as you go into older and older terraces, by the time you get to terraces that are 2 million years old, much of that goethite has been replaced by hematite, the mineral on Mars. And it’s a fairly coarse-grained hematite, which is also what we see at Mars.

So the first thing we learn at Rio Tinto is that one doesn’t need to think only about processes that deposit coarse-grained hematite from the get-go. It can form during what geologists call diagenesis. That is, it can form by processes that affect the rocks through time, and it can actually do that at low temperatures and without being deeply buried and subjected to high pressure. So in that sense, Rio Tinto shows us another way in which the hematite in Meridiani could have gotten there. It expands the options we consider.

AM: When geologists say things like “low temperature,” they often mean something different than the rest of us do.

AK: When I say “low temperature,” I’m talking about the temperatures that you and I experience on a daily basis, room temperature. I would guess that most of the Rio Tinto groundwaters are between 20 and 30 degrees Celsius, maybe 70 to 80 degrees Farenheit.

AM: Does the texture of the rock change over time as a mineral goes through the process of diagenesis?

AK: Yes, it does. Although what’s interesting is that while texture at the level of what the microscopic imager can see definitely changes through diagenetic history, larger scale features of deposition that you would see by looking closely at the outcrop with Pancam appear to be persistent. So, even though the rock is going through these changes, it retains sedimentary signatures of its formation, which is exciting. That’s important.

AB: You say that at Rio Tinto you can see a 2-million-year slice that shows you the diagenetic process over time. But the outcrops that Opportunity has seen at Meridiani could be 2 billion years old. Would they still retain any useful information after that long?

AK: Here’s the good news about geology: For sedimentary rocks, in particular, most of the changes that a rock undergoes it undergoes very early in its history. Unless a rock undergoes metamorphism, getting buried and subjected to high pressures and temperature, within at most a few million years of its formation it stabilizes into a form that it will retain indefinitely.

I work, in my day job, on Precambrian rocks on this planet. And I can guarantee you that when I look at a sedimentary rock that’s a billion years old, most of the changes that that rock underwent happened within the first 200 thousand years of its life. And then it stabilizes, and just waits for a geologist.

AM: And we have no reason to believe that physics behaves differently on Mars?

AK: That’s what we have going for us. I’ve said this before in terms of astrobiology: When you’re looking for life beyond our planet, you have no assurance that biology somewhere else will be the same as it is here. But you have pretty good assurance that physics and chemistry will be the same.

AM: Part of what makes Meridiani interesting is that it’s unlike just about any place else on Mars. Even if you’re able to figure out the history of Meridiani, to what extent will you be able to generalize that knowledge to Mars as a whole?

AK: I think it will certainly constrain the way we think about Mars as a whole planet. It may be that, in terms of the overall chemical and rock signature of Mars, that Gusev will turn out to be a better standard-issue Mars surface. That is, most of Mars – in fact, almost all of Mars – is surfaced with basalt, and then covered with fine dust. And that’s what we see at Gusev.

Now, it turns out that if you strip away the signal of hematite from the signatures of surface materials in Meridiani that we’ve gotten from orbit, it’s also mainly basalt. So it’s not a completely anomalous part of the planet. It appears to be a representative part of the planet at heart, with this unique hematite signal layered onto it.

One of the features of the Meridiani iron deposit is that, while it’s local with respect to the whole planet, it’s geographically widespread in that you have thousands of square kilometers that give this signature.

Many people think that hydrothermal processes and groundwater processes will give only small local iron signals, but in fact, the hematite-rich layers in the Rio Tinto deposit, go for several thousand square kilometers. Because these groundwaters spread out in a layer over a wide area.

So the Rio Tinto iron deposits do several things that we should keep in mind at Meridiani. They combine ancient hydrothermal and younger low-temperature processes; they need water; they can be layer forming; and they can be widespread.

They’re not the only set of processes that could to that, by any means. I’m not particularly prejudiced in favor of Rio Tinto as a better analog to Meridiani than anything else. I just think that as we go into this exploration we need to at least keep in our memory file as many different products and processes dealing with iron as we can.

All of the different settings for iron deposition and processes of iron deposition we see on this planet carry chemical and textural signals that Opportunity could detect on Meridiani. We can use those comparisons to help us to figure out how the Meridiani hematite formed.

AM: One of the intriguing aspects of Rio Tinto as a research site is that even though the water in the river is highly acidic, there are bacteria living in it. When you look at the ancient hematite deposits in that region, do you see fossil bacteria?

AK: Yes, you do. In fact, one of the things that attracted me to work with my Spanish colleagues was not that it’s an oddball environment today. While it’s kind of fun to be interested in life on the environmental fringes today, most life – and much of what you can learn about biology today – comes from ordinary organisms living in ordinary circumstances. That’s where 99 percent of the diversity of life is.

On the other hand, there’s a great question that can be asked at Rio Tinto. We can see the processes that formed the Rio Tinto iron deposits going on today; we can see the chemical processes; we can see what biology is in the environment. But the real question that one wants to keep in mind when thinking about Meridiani is: What, if any, signatures of that biology actually get preserved in diagenetically stable rocks?

One is that. If you were lucky enough to have access to a microscope – this would probably be at a resolution beyond what you could hope for from the microscopic imager – you could see individual microbial filaments that have been beautifully preserved. So that’s the first good news is that diagenetically stabilized iron can retain a microscopic imprint of biology.

The better news is that there are two features of biology that get preserved in the more eyeball-level textures in these rocks.

One is that you sometimes get little bubbles forming because of gas emanation from metabolism. And some of those will actually roof over with iron minerals and can be preserved through diagenesis. And that’s pretty much true through most sedimentary rocks that we find in the geologic column. You can get preserved gas spaces and those gas spaces are invariably associated with biological production of gases.

AM: How invariably?

AK: In our experience on Earth, it’s pretty much 100 percent. What you’d want to ask is: What processes other than biology might give rise to gases within a sediment on a planet? That’s something that you can do experiments on. I don’t know that anyone’s bothered to do them on this planet. Because, frankly, biology is so pervasive that that’s the main game in town, anyway. But one could do the experiments.

The other thing, which I feel even more strongly about, is that many times, where there are microbial populations, they form these beautiful groups of filaments that just string out across the surface. They almost look like the mane of a horse. Now the great thing is that, when minerals are deposited in these environments, they actually nucleate on these strings of filaments, and you get beautiful sedimentary textures that, again, look like the mane of a horse.

You can see them in Yellowstone Park, in both siliceous and carbonate-precipitating strings. If you go to places like Mammoth Springs, you can see it happening today. And if you hike into the hinterland, you can see ancient examples of that, beautiful signatures preserved in the rock.

In Rio Tinto, you can see iron depositing on these filaments; and in the 2 million year old terraces, you can see these filamentous iron textures. And there, again, I know of no process other than biology that could form those. So that’s truly something to keep your eyes out for whenever you’re looking at a precipitated rock on Mars.

AM: And you could see these with Pancam?

AK: If you took a Pancam to Rio Tinto or Yellowstone Park, they would jump out at you. Absolutely.

AM: If it turns out that the bedrock at the Opportunity landing site is made up of sedimentary deposits, does that mean that when those sediments were laid down, there had to be liquid water around?

AK: Very likely.

AM: So if they were sedimentary, and Pancam saw some sort of texture that on Earth is indicative of biology, would that mean that Opportunity had come close to finding evidence of life on Mars?

AK: Those are big ifs, but it would be a big day.

Let’s back up a second, because it gets to a little bit of philosophy about how you actually look for these things. A couple of years ago, NASA embarked on a funding campaign to essentially try and anticipate any kind of suggestively biological signature that might be found in any kind of exploration of another planet so that we wouldn’t be seen to be scratching our heads.

But the plain fact is that you can’t anticipate anything you might see. So what I think is a more realistic scenario is that you do your exploration, and if, in the course of that exploration, you find a signal that is (a) not easily accounted for by physics and chemistry or (b) reminiscent of signals that are closely associated with biology on Earth, then you get excited.

What will happen then, I can guarantee you, is that 100 enterprising scientists will go into the lab and see how, if at all, they can simulate what you see – without using biology. And I think that’s the right thing to do. For things where the stakes are so high, I think one wants to be as careful and sober about this as you can be. And certainly that means knowing a lot more about the generative capacity of physical and chemical processes to implant both chemical and textural signatures in a rock than we know about today.

Absent astrobiology, nobody would waste their time doing these things because, on Earth, we know that there has been biology for most of the planet’s history. Biology is everywhere. Biology is pre-eminent in the signals that it imparts to sedimentary rocks. So who is going to spend five years of their time as a young scientist trying to generate a signal by abiological means that’s closely associated with biology? However, you switch to Mars and there are a lot more reasons to do that kind of thing.

AM: If one of the MER rovers found a rock that seemed to contain evidence of martian biology, would NASA want go back to that spot and bring it home?

AK: You bet. Depending on what we find in Meridiani – not to prejudice what we find – it may make it either a very high-priority site for NASA to return with more sophisticated equipment and be a very top priority site for sample return; or we may write it off.

That’s the whole reason for this sort of incremental work. I actually like the whole architecture of NASA’s plan to go one step at a time, do each step carefully, and in step two build on what you learned in step one. It makes sense.

AM: I realize I’m asking you to speculate, here, but what do you think are the odds that Mars was once a living world?

AK: I really don’t know. But everything we’ve learned in the last few years suggests to me that water may have been episodic rather than persistent on Mars. And that lowers the probability for biology.

If water is present on the Martian surface for 100 years every 10 million years, that’s not very interesting for biology. If it’s present for 10 million years, that’s very interesting.

It is certainly not a given that we will find that Mars was a biological planet. Half of my brain keeps trying to throw out a percentage, and I know it’s such a meaningless thing to do – I think I’m just going to not do it.

But I can tell you that one of the best chances we’re going to get for a number of years to address that question is right here in the iron deposits of Meridiani.

Original Source: Astrobiology Magazine

Closeup Look at Martian Soil

Image credit: NASA/JPL
This magnified look at the martian soil near the Mars Exploration Rover Opportunity’s landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured by the rover’s microscopic imager on the 10th day, or sol, of its mission and roughly approximates the color a human eye would see. Scientists are intrigued by the perfectly round pebbles, which most likely were formed by one of two geologic processes. The first, accretion, is the same mechanism by which pearls take shape in oysters: concentric layers of material build up around a “seed.” The seed, in this case, may be either waterborne particles or volcanic ash. In the second process, droplets of material are sprayed into the air, by either volcanic eruptions or asteroid impacts. The examined patch of soil is 3 centimeters (1.2 inches) across. The large, circular pebble in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed. This color composite was obtained by merging images acquired with the orange-tinted dust cover in both its open and closed positions. The blue tint at the lower right corner is a tag used by scientists to indicate that the dust cover is closed.

Original Source: NASA/JPL News Release

Columbia Astronauts Get Mountains on Mars

Image credit: NASA
NASA Administrator Sean O’Keefe today announced the martian hills, located east of the Spirit Mars Exploration Rover’s landing site, would be dedicated to the Space Shuttle Columbia STS-107 crew.

“These seven hills on Mars are named for those seven brave souls, the final crew of the Space Shuttle Columbia. The Columbia crew faced the challenge of space and made the supreme sacrifice in the name of exploration,” Administrator O’Keefe said.

The Shuttle Columbia was commanded by Rick Husband and piloted by William McCool. The mission specialists were Michael Anderson, Kalpana Chawla, David Brown, Laurel Clark; and the payload specialist was Israeli astronaut Ilan Ramon. On February 1, 2003, the Columbia and its crew were lost over the western United States during re-entry into Earth’s atmosphere.

The 28th and final flight of Columbia was a 16-day mission dedicated to research in physical, life and space sciences. The Columbia crew successfully conducted approximately 80 separate experiments during their mission.

NASA will submit the names of the Mars features to the International Astronomical Union for official designation. The organization serves as the internationally recognized authority for assigning designations to celestial bodies and their surface features.

An image taken by the Mars Global Surveyor Mars Orbiter Camera of the Columbia Memorial Station and Columbia Hills is available on the Internet at: http://www.jpl.nasa.gov/mer2004/rover-images/feb-02-2004/captions/image-10.html.

For information about NASA and the Mars mission on the Internet, visit: http://www.nasa.gov.

The Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Additional information about the project is available on the Internet at: http://marsrovers.jpl.nasa.gov.

Twin Rovers Examining at the Same Time

Image credit: NASA/JPL
Each of NASA’s two Mars Exploration Rovers is using its versatile robotic arm for positioning tools at selected targets on the red planet.

Also, a newly completed 360-degree color panorama from Opportunity shows a trail of bounce marks coming down the inner slope of the small crater where the spacecraft came to rest when it landed on Mars nine days ago.

Opportunity extended its arm early today for the first time since pre-launch testing. “This was a great confirmation for the team,” said Joe Melko of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. Melko is mechanical systems engineer for the arm, which is also called the instrument deployment device.

Mission controllers at JPL are telling Opportunity to use two of the instruments on the arm overnight tonight to examine a patch of soil in front of the rover. A microscope on the arm will reveal structures as thin as a human hair and a Moessbauer Spectrometer will collect information to identify minerals in the soil, according to plans. Tomorrow, the rover will be told to turn the turret at the end of the arm in order to examine the same patch of soil with another instrument, the alpha particle X-ray spectrometer, which reveals the chemical elements in a target.

Spirit is now in good working order after more than a week of computer-memory problems. It is brushing dust off of a rock today with the rock abrasion tool on its robotic arm. After the brushing, Spirit will use the microscope and two spectrometers on the arm to examine the rock.

“We’re moving forward with our science on the rock Adirondack,” said JPL’s Jennifer Trosper, Spirit mission manager. Reformatting of Spirit’s flash memory was postponed from today to tomorrow. The reformatting is a precautionary measure against recurrence of the problem that prevented Spirit from doing much science last week.

Later in the week, Spirit will grind the surface off of a sample area on Adirondack with the rock abrasion tool to inspect the rock’s interior. After observations of Adirondack are completed, the rover will begin rolling again. “We are already strategizing how to drive far and fast,” Trosper said.

Observations by each rover’s panoramic camera help scientists choose where to drive and what to examine with the instruments on each rover’s arm. Dr. Jeff Johnson, a rover science team member from the U.S. Geological Survey’s Astrogeology Team, Flagstaff, Ariz., said that 14 filters available on each rover’s panoramic camera allow the instrument to provide much more information for identifying different types of rocks than can be gleaned from color images such as the new panoramic view.

“By looking at the brightness values in each of these wavelengths, we can start to get an idea of the things we’re interested in, especially to unravel the geological history of these landing sites,” Johnson said.

The main task for both rovers in coming weeks and months is to find clues in rocks and soil about past environmental conditions, particularly about whether the landing areas were ever watery and possibly suitable for sustaining life.

Each martian day, or “sol” lasts about 40 minutes longer than an Earth day. Spirit begins its 31st sol on Mars at 1:23 a.m. Tuesday, Pacific Standard Time. Opportunity begins its 11th sol on Mars at 1:44 p.m. Tuesday, PST. The two rovers are halfway around Mars from each other.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University, Ithaca, N.Y., at http://athena.cornell.edu.

Original Source: NASA/JPL News Release

Spirit is Fully Recovered

Image credit: NASA/JPL
NASA’s Mars Exploration Rover Spirit is healthy again, the result of recovery work by mission engineers since the robot developed computer-memory and communications problems 10 days ago.

“We have confirmed that Spirit is booting up normally. Tomorrow we’ll be doing some preventive maintenance,” Dr. Mark Adler, mission manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., said Sunday morning.

Spirit’s twin, Opportunity, which drove off its lander platform early Saturday, will be commanded tonight to reach out with its robot arm early Monday, said JPL’s Matt Wallace, mission manager. Opportunity will examine the soil in front of it over the next few days with a microscope and with a pair of spectrometer instruments for determining what elements and minerals are present.

For Spirit, part of the cure has been deleting thousands of files from the rover’s flash memory — a type of rewritable electronic memory that retains information even when power is off. Many of the deleted files were left over from the seven- month flight from Florida to Mars. Onboard software was having difficulty managing the flash memory, triggering Spirit’s computer to reset itself about once an hour.

Two days after the problem arose, engineers began using a temporary workaround of sending commands every day to put Spirit into an operations mode that avoided use of flash memory. Now, however, the computer is stable even when operating in the normal mode, which uses the flash memory.

“To be safe, we want to reformat the flash and start again with a clean slate,” Adler said. That reformatting is planned for Monday. It will erase everything stored in the flash file system and install a clean version of the flight software.

Today, Spirit is being told to transmit priority data remaining in the flash memory. The information includes data from atmospheric observations made Jan. 16 in coordination with downward-looking observations by the European Space Agency’s Mars Express orbiter. Also today, Spirit will make new observations coordinated with another Mars Express overflight and will run a check of the rover’s miniature thermal emission spectrometer.

Spirit will resume examination of a rock nicknamed Adirondack later this week and possibly move on to a lighter-colored rock by week’s end.

Each martian day, or “sol” lasts about 40 minutes longer than an Earth day. Spirit begins its 30th sol on Mars at 12:44 a.m. Monday, Pacific Standard Time. Opportunity begins its 10th sol on Mars at 1:05 p.m. Monday, PST. The two rovers are halfway around Mars from each other.

The main task for both Spirit and Opportunity in coming weeks and months is to find geological clues about past environmental conditions at their landing sites, particularly about whether the areas were ever watery and possibly suitable for sustaining life.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University, Ithaca, N.Y., at http://athena.cornell.edu.

Original Source: NASA/JPL News Release

James Cameron’s Plans for Mars

Image credit: James Cameron
As an artist and filmmaker, James Cameron is credited on major Hollywood productions in virtually all roles: writer, director, producer, editor, visual effects, actor, art director, and even crew. Cameron wrote and directed such science fiction classics as “Terminator 2: Judgement Day” (1991), “The Abyss” (1989), and “Aliens” (1986). He received an Academy Award for Best Director for 1997’s “Titanic,” which was also the largest grossing film in history.

Astrobiology Magazine’s Executive Producer, Helen Matsos, sat down with James Cameron and discussed his project slate. During their discussions, Cameron shared how he became interested in Mars and his unique renderings commissioned to represent the key stages in a future human mission to the red planet. As Cameron said about his directorial view: “I think that any kind of exploration should always try to acquire the highest level of imaging. That’s how you engage people — you can put them there, give them the sense that they’re standing there on the surface of Mars.”

The Design Reference Mission (DRM) covers Earth launch to Mars landing, Mars cruise to Mars launch, and Earth return. The mission entails sending cargo ahead, docking the crew at the space station, then meeting up with the cargo supplies once on Mars.

Cameron underscored the need to illustrate the details for each stage of the DRM. And whether deploying a crew or robotic explorers, the mission needed to connect more to a shared human story of discovery. A future Astrobiology Magazine feature will highlight Cameron’s reflections on making such a mission come to life, but this director’s preview offers tantalizing visual cues to what is going on robotically today on Mars.

“The [1997] Sojourner Rover became a character to millions of people, a protagonist in a story. How long is it going to survive, could it perform its mission? It wasn’t anthropomorphic in any way, there was absolutely no emotion in a little solar powered machine that was being commanded from eighty million miles away, and yet people thought of it as a character. The reason we thought of it as a character is that it represented us in a way. It was our consciousness moving that vehicle around on the surface of Mars. It’s our collective consciousness — focused down to that little machine – that put it there. So it was a celebration of who and what we are.”

“It takes our entire collective consciousness and projects it there – to that point in time and space. That’s what the Sojourner Rover did.”

“I was involved in a private company that was going to try to land two rovers on the Moon. That collapsed in the dot com crash – they ran out of money. I’m loosely involved with people who are going to be doing future robotic missions to Mars. I’m involved in terms of imaging, and of how imaging might be improved in terms of story telling. I’ve been very interested in the Humans to Mars movement –the ‘Mars Underground’ — and I’ve done a tremendous amount of personal research for a novel, a miniseries, and a 3-D film.”

“In doing this fictional story about the first humans to Mars — a subject that has been done in the movies, but never done very well, I think — people in the Hollywood community have no idea of what that means. The average person walking around has no idea of what’s involved. I called up NASA and said ‘who’s in charge of Mars?’ It turns out that NASA has (scientists studying Mars) everywhere, but there’s no one person in charge. It’s taken me years to ferret around and talk to everybody.”

In the course of designing this project, we never got past the design stage, although we will eventually. Right now it’s just, ‘what’s everything going to look like?’ What it looked like was determined by how it worked, and how it worked was determined by the mission architecture. ”

“The thing I found about human mission architectures for going to Mars is that if you change one piece or one assumption, it has a ripple effect through the whole thing, and it looks different coming out the other end. You do things differently, your spacecraft are configured differently, your surface mission looks different, the time you spend on the planet looks different. So a certain set of fundamental assumptions had to be made and then we had to design everything for what it was going to look like.”

“I wanted it to be highly realistic. Obviously I don’t think we can predict now, twenty-some years before the fact, exactly how it is going to be done, but we can make a set of very plausible assumptions. We got involved in the design of it, and predicated it on a series of assumptions, and then I went to JSC (Johnson Space Center) to talk to some of the people in the human exploration and development group. I asked, ‘Does this look like what you guys thought?’ They had created overall architectural guidelines in the DRM – the Design Reference Mission – but there were no pictures. Nobody knew what it was really going to look like.”

I said, ‘Look, this is our proposal for what a Hab would look like, and what a pressurized rover would look like, and we made certain assumptions based on how we operate deep submersibles, for example, in terms of how the manipulators would work taking samples and so on.’ And they said, ‘Hey, this is neat! Thanks! If you ever want to get out of filmmaking, come here and hang with us.’

The stages of the Cameron’s Mars Reference Design take a crew and cargo ship from a heavy-lift launch to the flat, red plains of Mars. See the slideshow version.

A Biconic Aeroshell and Fairing is used to transport payloads into space atop a heavy launch vehicle. A single cargo mission will preceed the crew to Mars. The cargo mission provides all the necessary equipment a Mars crew will require to explore the Martian surface for 500 to 600 days.

Included in this cargo are the Cargo Landing Vehicle (CLV), an In Situ Propellant Production Plant Reactor and two inflatable surface Habitats (Hab). This cargo will be placed in the Biconin Aeroshell and will Aerobraking to slow its descent into the martian atmosphere. A heavy-lift launch vehicle will deliver the Crew Transfer Vehicle (CTV) into low Earth orbit (LEO). The CTV will deploy in orbit and rendezvous with the crew at the International Space Station (ISS).

The CTV comprises several systems:an inflatable habitat called the TransHab; the Crew Lander and Rover; and the Aeroshell. The petals of the Aeroshell deploy and lock in place. After cruise, the CTV will tumble end-over-end during Trans-Mars Injection (TMI), creating a 0.38 times earth gravity environment, identical to conditions on Mars. The Crew Lander and Rover, along with their aeroshell will separate from the CTV and enter into the martian atmosphere.

Upon successful aerobraking in the Mars’ atmosphere, the Biconic aeroshell will fall away as large parachutes further assist to slow the CLV in its powered landing. The crew will use steering flaps and reaction control thrusters to guide their entry. During descent, the packed Habs are jettisoned.

The jettisoned Habs will inflate during its independent descent, providing airbag protection to the Cargo Modules housed inside. The aeroshell itself is jettisoned and large parachutes are used to slow the Crew Lander and Rover during descent.

The Crew Lander and Rover will use powerful engines to hover before landing. The Rover’s variable suspension will be capable of absorbing the shock of landing as well as increasing the Rover’s ground clearance. In addition to the Rover’s descent engines, the vehicle will serve as transport and mobile laboratory. A robotic manipulator and crane will allow the crew to interact remotely with the surface. Forward and dorsal docking tunnels simplify crew transfers to the Hab. Power will come from crygenic fuel tanks and a photovoltaic array. The vehicle’s port side includes a centrifugal blower to keep dust to a minimum.

On the surface, the crew must locate both Habs and transport them to the CLV site. The Crew Lander/Rover docks with one of the Habs via the forward hatch. The Mars Mission Base will have a modular design of components that allow for several geometric configurations and expansion.

After landing, the In Situ Propellant Production (ISPP) plant deploys nuclear reactors to power the production of water, oxygen and methane using hydrogen and carbon dioxide as raw materials.

The CLV and ISPP will provide liquid oxygen and methane (LOX/CH4) propellant to the Ascent Crew vehicle. The Ascent Crew vehicle will rendezvous with the Earth Return Vehicle in orbit around Mars.

Original Source: Astrobiology Magazine