Category: Mars

I made a mention in yesterday’s newsletter that I had a few Gmail invites left over. You know, this is Google’s competitor to Hotmail and Yahoo that gives you a free email address with one GB of space. It’s still in beta, but I’m really impressed with it so far. I made a small mention down at the bottom, but I was still deluged with email requests for a Gmail invite. I had posted 6 invites in the Universe Today forum, and they were snapped up in a few minutes.

Now, I know there are hundreds of you reading this newsletter with some Gmail invites to spare, so I was wondering if you could help out. Visit the forum, head down to the bottom and post any spare invite links that you have. I’ve posted instructions in the forum on how to do this. Do not email me directly asking for an invite.

Here’s a link to the thread in the forum where everyone is posting their invites. Please help out if you can.

Thanks!

Fraser Cain
Publisher
Universe Today

P.S. The Universe Today forum has nearly 3,000 members now from all around the world. Come, hang out, and chat with other space enthusiasts!

This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA?s Mars Express spacecraft, shows the eastern rim of the Martian impact crater Huygens.

The image was taken during orbit 532 in June 2004 with a ground resolution of approximately 70 metres per pixel. The displayed region is centred around longitude 61? East and latitude 14? South.

Huygens is an impact structure, about 450 kilometres wide, located in the heavily cratered southern highlands of Mars. Crater counts of the rim unit of the impact basin indicate that it is almost 4000 million years old.

This implies that this basin was formed in the early history of the planet and indicates a period of heavy bombardment in roughly the first 500 million years of the planet?s lifetime.

The basin shows an inner ring that has been subsequently filled by sediments transported into the crater.

Thia image showa part of the eastern rim of the crater. The rim is heavily eroded and shows a ?dendritic? pattern. This observation suggests surface water run-off.

Dendritic systems are the most common form of drainage system found on Earth. They consist of a main ?river? valley with tributaries with their own tributaries. From above, they look like a tree or a river delta in reverse.

The valley system is blanketed by dark material, which was either transported by a fluid running through the channels or by wind-driven (?aeolian?) processes. Part of the area has been covered by slightly redder material, which implies a different chemical composition.

Original Source: ESA News Release

This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA?s Mars Express spacecraft, shows a part of the southern highlands of Mars, called Promethei Terra.

The image was taken during orbit 368 in May 2004 with a ground resolution of approximately 14 metres per pixel. The displayed region is centred around longitude 118? East and latitude 42? South.

It shows an area in the Promethei Terra region, east of the Hellas Planitia impact basin. The smooth surface is caused by a layer of dust or volcanic ash that is up to several tens of metres thick.

This layer has covered all landforms, and even young impact craters have lost their contours due to in-fill and collapse of their fragile crater walls. This layer has been removed by the wind at some ridges and crater walls.

Although the image was taken at high resolution and show very fine detail, this covering layer leads to a slightly fuzzy appearance.

The large impact crater in the southern part of the image is 32 kilometres wide and up to 1200 metres deep. The dark crater floor is most likely the result of ?deflation?, the geological term for the lifting and removal of loose material.

The dust removed here has accumulated in the southern part of the crater, forming a thick layer. The numerous dark tracks to the north-western and west are ?dust devil? tracks.

These atmospheric ?eddies?, like tornadoes on Earth, remove the uppermost dust layers which have a slightly different colour to the now-exposed surface. The tracks can be more than 20 kilometres long and contrast prominently with the lighter-coloured surroundings.

Dust devil tracks provide short-lived evidence of the ongoing geological and atmospheric activity on Mars, which consists mainly of the transport of dust by wind.

Another sign for this ?aeolian? (wind-related) activity in the area is the existence of small dune fields that have formed in some of the depressions. They can be seen in the crater in the north and in its surroundings (see close-up).

The dust devils are not limited by geomorphological boundaries: for example, their tracks cross the crater rim. Dust devil tracks can also be seen on the thick dust layer in the southern part of the crater.

Due to the thickness of the dust layer, no darker material is exposed here. The dust devil tracks show two distinct directions of movement: east to west and south-east to north-west.

Original Source: ESA News Release

NASA’s Spirit and Opportunity have been exploring Mars about three times as long as originally scheduled. The more they look, the more evidence of past liquid water on Mars these robots discover. Team members reported the new findings at a news briefing today.

About six months ago, Opportunity established that its exploration area was wet a long time ago. The area was wet before it dried and eroded into a wide plain. The team’s new findings suggest some rocks there may have gotten wet a second time, after an impact excavated a stadium sized crater.

Evidence of this exciting possibility has been identified in a flat rock dubbed “Escher” and in some neighboring rocks near the bottom of the crater. These plate-like rocks bear networks of cracks dividing the surface into patterns of polygons, somewhat similar in appearance to cracked mud after the water has dried up here on Earth.

Alternative histories, such as fracturing by the force of the crater-causing impact, or the final desiccation of the original wet environment that formed the rocks, might also explain the polygonal cracks. Rover scientists hope a lumpy boulder nicknamed “Wopmay,” Opportunity’s next target for inspection, may help narrow the list of possible explanations.

“When we saw these polygonal crack patterns, right away we thought of a secondary water event significantly later than the episode that created the rocks,” said Dr. John Grotzinger. He is a rover-team geologist from the Massachusetts Institute of Technology, Cambridge, Mass. Finding geological evidence about watery periods in Mars’ past is the rover project’s main goal, because such persistently wet environments may have been hospitable to life.

“Did these cracks form after the crater was created? We don’t really know yet,” Grotzinger said.

If they did, one possible source of moisture could be accumulations of frost partially melting during climate changes, as Mars wobbled on its axis of rotation, in cycles of tens of thousands of years. According to Grotzinger, another possibility could be the melting of underground ice or release of underground water in large enough quantity to pool a little lake within the crater.

One type of evidence Wopmay could add to the case for wet conditions after the crater formed would be a crust of water-soluble minerals. After examining that rock, the rover team’s plans for Opportunity are to get a close look at a tall stack of layers nicknamed “Burns Cliff” from the base of the cliff. The rover will then climb out of the crater and head south to the spacecraft’s original heat shield and nearby rugged terrain, where deeper rock layers may be exposed.

Halfway around Mars, Spirit is climbing higher into the “Columbia Hills.” Spirit drove more than three kilometers (approximately two miles) across a plain to reach them. After finding bedrock that had been extensively altered by water, scientists used the rover to look for relatively unchanged rock as a comparison for understanding the area’s full range of environmental changes. Instead, even the freshest-looking rocks examined by Spirit in the Columbia Hills have shown signs of pervasive water alteration.

“We haven’t seen a single unaltered volcanic rock, since we crossed the boundary from the plains into the hills, and I’m beginning to suspect we never will,” said Dr. Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the science payload on both rovers. “All the rocks in the hills have been altered significantly by water. We’re having a wonderful time trying to work out exactly what happened here.”

More clues to deciphering the environmental history of the hills could lie in layered rock outcrops farther upslope, Spirit’s next targets. “Just as we worked our way deeper into the Endurance crater with Opportunity, we’ll work our way higher and higher into the hills with Spirit, looking at layered rocks and constructing a plausible geologic history,” Squyres said.

Jim Erickson, rover project manager at JPL, said, “Both Spirit and Opportunity have only minor problems, and there is really no way of knowing how much longer they will keep operating. However we are optimistic about their conditions, and we have just been given a new lease on life for them, a six-month extended mission that began Oct. 1. The solar power situation is better than expected, but these machines are already well past their design life. While they’re healthy, we’ll keep them working as hard as possible.”

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

Original Source: NASA/JPL News Release

Epsom-like salts believed to be common on Mars may be a major source of water there, say geologists at Indiana University Bloomington and Los Alamos National Laboratory. In their report in this week’s Nature, the scientists also speculate that the salts will provide a chemical record of water on the Red Planet.

“The Mars Odyssey orbiter recently showed that there may be as much as 10 percent water hidden in the Martian near-surface,” said David Bish, Haydn Murray Chair of Applied Clay Mineralogy at IU and a co-author of the report. “We were able to show that under Mars-like conditions, magnesium sulfate salts can contain a great deal of water. Our findings also suggest that the kinds of sulfates we find on Mars could give us a lot of insight into the history of water and mineral formation there.”

The scientists learned that magnesium sulfate salts are extremely sensitive to changes in temperature, pressure and humidity. For that reason, the scientists argue that information contained in the salts could be easily lost if samples were brought back to Earth for study. Instead, they say, future missions to Mars should measure the properties of the salts on site.

The existence of magnesium sulfate salts on Mars was first suggested by the 1976 Viking missions and has since been confirmed by the Mars Exploration Rover as well as the Odyssey and Pathfinder missions. One way to quash remaining doubts that the salts are really there, however, would be to equip a Martian rover with an X-ray diffractometer — an instrument that analyzes the properties of crystals. Coincidentally, such a device could also be used to examine magnesium sulfate salts on Mars. Bish and collaborators from NASA Ames and Los Alamos are currently developing a miniaturized X-ray diffractometer with NASA funding.

Some magnesium sulfate salts trap more water than others. Epsomite, for example, has the most water in it — 51 percent by weight — while hexahydrite and kieserite have less (47 percent and 13 percent by weight, respectively). The proportion of water to magnesium sulfate affects the chemical properties of the different salts.

While varying temperature, pressure and humidity inside an experimental chamber, the scientists studied how the different magnesium salts transform over time.

When temperature and pressure inside an experimental chamber were lowered to Mars-like conditions (minus 64 degrees Fahrenheit, and less than 1 percent of Earth’s normal surface pressure), crystals of epsomite initially transformed into slightly less watery hexahydrite crystals and then became disorganized, but they still contained water. In contrast, “kieserite doesn’t let go of its water very easily, even at very low pressure and humidity or at elevated temperatures,” Bish said.

But when the scientists increased humidity inside the experimental chamber, they found that kieserite transformed into hexahydrite and then epsomite, which have more water.

Bish and his Los Alamos colleagues believe that the proportion and distribution of hexahydrite, kieserite and other magnesium sulfate salts on Mars may hold a record of past changes in climate and whether or not water once flowed there. However, kieserite might not be preserved through cycles of wetting and drying because of its ability to rehydrate to hexahydrite and epsomite, which can then become amorphous through drying.

Los Alamos National Laboratory geologists David Vaniman, Steve Chipera, Claire Fialips, William Carey and William Feldman also contributed to the study. It was funded by LANL Directed Research and Development Funding and NASA Mars Fundamental Research Program grants.

Original Source: Indiana University News Release

Engineers on NASA’s Mars Exploration Rover team are investigating possible causes and remedies for a problem affecting the steering on Spirit.

The relay for steering actuators on Spirit’s right-front and left-rear wheels did not operate as commanded on Oct. 1. Each of the front and rear wheels on the rover has a steering actuator, or motor, that adjusts the direction in which the wheels are headed independently from the motor that makes the wheels roll. When the actuators are not in use, electric relays are closed and the motor acts as a brake to prevent unintended changes in direction.

Engineers received results from Spirit today from a first set of diagnostic tests on the relay. “We are interpreting the data and planning additional tests,” said Rick Welch, rover mission manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “We hope to determine the best work-around if the problem does persist.”

Spirit and its twin, Opportunity, successfully completed their three-month primary missions in April and five-month mission extensions in September. They began second extensions of their missions on Oct. 1. Spirit has driven more than 3.6 kilometers (2.2 miles), six times the distance set as a goal for mission success. It is climbing into uplands called the “Columbia Hills.”

JPL’s Jim Erickson, rover project manager, said, “If we do not identify other remedies, the brakes could be released by a command to blow the fuse controlling the relay, though that would make those two brakes unavailable for the rest of the mission.” Without the steering-actuator brakes, small bumps or dips that a wheel hits during a drive might twist the wheel away from the intended drive direction.

“If we do need to disable the brakes, errors in drive direction could increase. However, the errors might be minimized by continuing to use the brakes on the left-front and right-rear wheels, by driving in smaller segments, and by adding a software patch to reset the direction periodically during a drive,” Erickson said. Engineers believe the steering-brake issue is not related to excessive friction detected during the summer in the drive motor for Spirit’s right-front wheel, because the steering actuator is a different motor.

Meanwhile, the team continues to use Spirit’s robotic arm and camera mast to study rocks and soils around the rover, without moving the vehicle until the cause of the anomaly is understood and corrective measures can be implemented.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Science Mission Directorate, Washington. Additional information about the project is 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

This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA?s Mars Express spacecraft, shows the Claritas Fossae tectonic grabens and part of the Solis Planum plains.

The image was taken during orbit 508 in June 2004 with a ground resolution of approximately 40 metres per pixel. The displayed region is the eastern part of Claritas Fossae and the western part of Solis Planum at longitude 260? East and latitude of about 28? South.

The diffuse blue-white streaks in the northern parts of the scene are clouds or aerosols.

The Claritas Fossae (?fossa? is Latin for trough) region is characterised by systems of ?grabens? running mainly north-west to south-east. These can be traced several hundred kilometres up to the northern Tharsis shield volcanoes.

A graben forms when a block of the planet?s crust drops down between two faults, due to extension, or pulling, of the crust.

Grabens are often seen together with features called ?horsts?, which are upthrown blocks lying between two steep-angled fault blocks.

A ?horst and graben? system can occur where there are several parallel faults.

Geographically, the grabens separate the eastern volcanic plains of the Solis Planum region from the western Daedalia Planum lava plains.

The lava blankets of the Solis Planum area cover the eastern parts of the older Claritas Fossae ridge and surround some of the higher ground.

The geological history of this region can be reconstructed by analysing the layers of tectonic grabens, impact craters, volcanic features and even small valley networks.

The complexity of this superposition record suggests that some of the events took place at the same time.

The detailed view of the large southern impact crater shows patches of dark material which are located near the central and marginal parts of the impact crater floor. This material may be of volcanic origin.

The HRSC experiment on ESA?s Mars Express mission is led by the Principal Investigator Prof. Gerhard Neukum of the Freie Universit?t Berlin, who also designed the camera. The experiment?s science team consists of 45 Co-Investigators from 10 nations.

The camera was developed at the German Aerospace Centre (DLR) and built in co-operation with industrial partners EADS Astrium, Lewicke Microelectronic GmbH and Jena-Optronic GmbH). The HRSC is operated by DLR Institute of Planetary Research through ESA?s European Space Operations Centre, Darmstadt.

The systematic processing of image data is carried out at DLR. The images shown here were processed by the FU Berlin group in co-operation with DLR, Berlin.

Original Source: ESA News Release

Image credit: ISECCo
Ray and some friends built Mars Base Zero a few years ago on a borrowed plot of land just outside Fairbanks, Alaska. It’s a fairly normal looking greenhouse 11 metres (36 feet) long, and two-thirds as wide. One half of the cylindrical roof is clear plastic, and the other half is well insulated. There’s also a small apartment attached to one end for Ray to live in while he tends to his Martian garden.

Inside you’ll find a healthy crop of potatoes, carrots, cabbage, tomatoes, and plenty of other produce to make a vegan smile – mostly, though, you’ll find potatoes. Through several years of experimentation, Ray has learned that a single human requires about 80 square metres (864 square feet) of soil to grow enough food to survive.

Assuming you’re willing to eat a lot of potatoes.

“We tried growing wheat, but we could have gotten several pounds of potatoes for an area that gave me just a cupful of wheat. I’m guessing that 4-5 chickens would eat the same amount as me. We might try fish, though.”

Collins is one of the original co-founders of the International Space Exploration and Colonization Co. (ISECCo); a non-profit organization hoping to contribute knowledge to the human exploration of space. Instead of building rockets in their garages, the ISECCo team decided to do something much lower budget: Closed Ecological Life Support System Research. Sort of like Biosphere II, but without all the fancy ecosystems… and drama.

They started in 1988, and built a series of experiments leading up to Mars Base Zero – a $30,000 investment. Maintaining the experiment has only cost $900 this year, since they planted the crops in May 2004. Ray figures he’s put $40,000 of his own money into the various experiments since 1988.

The only purpose of Mars Base Zero is to understand how much space is required, and which crops to grow to keep an astronaut well fed. If you could seal it up tight, and ship it to Mars, Ray figures that it would get enough sunlight on Mars to have the plants nearly growing as well as they do in Alaska.

Ray began this experiment on September 17, and he’s been keeping a detailed log of the food he’s been eating – the potatoes he’s been eating – and the, um, “waste” he’s been generating. He hasn’t lost any weight so far, but he has to eat several kilograms of food every day just to maintain. A nutritionist probably wouldn’t be too pleased with his diet so far, but Ray’s aware of the inadequacies and has new crops planned for next time around. If everything goes well, he’ll stay in for at least 30 days, and maybe as long as 60 days if the potatoes hold out. His wife is expecting to deliver their second child in December, so Ray’s got a hard deadline anyway.

Normally they plant in the spring, and then harvest in the fall. But Ray would like to try planting continuously, and keep it going as long into the winter as he can afford to pay for lights and heat. Eventually he hopes they’ll get to the point that it’s a year round operation.

And then they’ll take the experiment to the next level… underground.

ISECCo plans to build an underground dome, called Nauvik (Eskimo term for “nurturing place”), twice the same area as the greenhouse, but seal it completely off from the Earth’s environment. Water, air and other nutrients would be carefully monitored, and the plants would be grown by powerful lamps – the electricity bill alone will probably run $5,000 a month. The advantage is that they could simulate a lunar or Martian environment; even experimenting with different air pressures to see how the plants react. With the heat from the lamps, Ray expects one of the most difficult challenges will be keeping it cool.

It’ll be an expensive proposition. Especially without government or NASA funding. “We responded to a NASA request-for-proposal that was looking for unique ideas in closed system life support.” Ironically, the agency complained that their idea was “too unique”.

Maybe the astronauts weren’t willing to eat that many potatoes.

Written by Fraser Cain

NASA’s Mars Global Surveyor, starting its third mission extension this week after seven years of orbiting Mars, is using an innovative technique to capture pictures even sharper than most of the more than 170,000 it has already produced.

One dramatic example from the spacecraft’s Mars Orbiter Camera shows wheel tracks of NASA’s Mars Exploration Rover Spirit and the rover itself. Another tells scientists that no boulders bigger than about 1 to 2 meters (3 to 7 feet) are exposed in giant ripples created by a catastrophic flood.

Those examples are available online at http://www.msss.com/mars_images/moc/2004/09/27/ and http://mars.jpl.nasa.gov/mgs. In addition, about 24,000 newly catalogued images that Mars Global Surveyor took between October 2003 and March 2004 have been added to the Mars Orbiter Camera Image Gallery at http://www.msss.com/moc_gallery/. These include additional pictures of the Mars Exploration Rover sites seen from orbit.

“Over the past year and a half, the camera and spacecraft teams for Mars Global Surveyor have worked together to develop a technique that allows us to roll the entire spacecraft so that the camera can be scanned in a way that sees details at three times higher resolution than we normally get,” said Dr. Ken Edgett, staff scientist for Malin Space Science Systems, San Diego, Calif., which built and operates the Mars Orbiter Camera. The technique adjusts the rotation rate of the spacecraft to match the ground speed under the camera.

“The image motion compensation is tricky and the spacecraft does not always hit its target. However, when it does, the results can be spectacular,” Edgett said.

The Mars Orbiter Camera acquires the highest resolution images ever obtained from a Mars-orbiting spacecraft. During normal operating conditions, the smallest objects that can be resolved on the martian surface in these images are about 4 to 5 meters (13 to 16 feet) across. With the adjusted-rotation technique, called “compensated pitch and roll targeted observation,” objects as small as 1.5 meters (4.9 feet) can be seen in images from the same camera. Resolution capability of 1.4 meters (4.6 feet) per pixel is improved to one-half meter (1.6 feet) per pixel. Because the maneuvers are complex and the amount of data that can be acquired is limited, most images from the camera are still taken without using that technique.

Mars Global Surveyor began orbiting Mars on Sept. 12, 1997. After gradually adjusting the shape of its orbit, it began systematically mapping the planet in March 1999. The Mars Orbiter Camera’s narrow-angle camera has now examined nearly 4.5 percent of Mars’ surface, including extensive imaging of candidate and selected landing sites for surface missions. The Mars Orbiter Camera also includes a wide-angle camera that observes the entire planet daily.

“Mars Global Surveyor has been productive longer than any other spacecraft ever sent to Mars, since it surpassed Viking Lander 1’s longevity earlier this year and has returned more images than all past Mars missions combined,” said Tom Thorpe, project manager for Mars Global Surveyor at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. The mission will complete its 25,000th mapping orbit on Oct. 11.

Principal goals for the orbiter’s latest mission extension, beginning Oct. 1, include continued weather monitoring to form a continuous set of observations with NASA’s next Mars mission, Mars Reconnaissance Orbiter, scheduled to reach the red planet in 2006; imaging of possible landing sites for the Phoenix 2007 Mars Scout lander and 2009 Mars Science Laboratory rover; continued mapping and analysis of key sedimentary-rock outcrop sites; and continued monitoring of changes on the surface due to wind and ice. Because the narrow-angle camera has imaged only a small fraction of the surface, new discoveries about surface features are likely to come at any time. The extension runs two years, through September 2006, with a budget of $7.5 million per year.

Dr. James Garvin, NASA’s chief scientist for Mars and the Moon, said, “Mars Global Surveyor continues to catalyze new science as it explores Mars at scales compatible with those that our Mars Exploration Rovers negotiate every day, and its extended mission will continue to set the stage for upcoming observations by the Mars Reconnaissance Orbiter.”

Additional information about Mars Global Surveyor is available online at: http://mars.jpl.nasa.gov/mgs/. In addition to semi-annual releases of large collections of archived pictures, the Mars Orbiter Camera team posts a new image daily and last year began soliciting public suggestions for camera targets on Mars. These materials can be viewed online at http://www.msss.com . For more information about NASA and other space science programs on the Internet, visit http://www.nasa.gov.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Global Surveyor mission for NASA’s Science Mission Directorate, Washington, D.C. JPL’s industrial partner is Lockheed Martin Space Systems, Denver, which built and operates the spacecraft.

Original Source: NASA/JPL News Release

Image credit: ESA
Recent results from the ASPERA-3 instrument on board Mars Express confirm that a very efficient process is at work in the Martian atmosphere which could explain the loss of water. Water is believed to have once been abundant on the Red Planet. Professor Rickard Lundin, leader of the ASPERA-3 team, describes these findings in a paper published in the latest issue of ?Science?.

Mars is bombarded by a flood of charged particles from the Sun, commonly called the ?solar wind? and consisting of electrons and alpha particles. The solar wind erodes the atmosphere of Mars, and is believed to have stripped away a large amount of water that was present on the planet about 3.8 billion years ago. Geological evidence, as recently confirmed by images from the High Resolution Stereo Camera (HRSC) onboard Mars Express, indicates that water flows and even an ocean in the Northern hemisphere shaped the surface of Mars.

Today, water still exists on the Red Planet, but less than in the past. Observations made earlier this year by the OMEGA instrument on Mars Express showed that Mars has vast fields of perennial water ice, stretching out from its south pole.

The ASPERA-3 instrument on board Mars Express aims to answer the question of whether the solar wind interaction with the upper atmosphere of Mars contributes to the depletion of water. It is measuring a process called ?solar wind scavenging?, or the slow ?invisible? escape of volatile gases and liquid compounds which make up the atmosphere and hydrosphere of a planet. Using plasma spectrometers and a special imager to detect energetic neutral atoms, ASPERA-3 is making global and simultaneous measurements of the solar wind, the inflow of energetic particles, and also the ?planetary wind?, which is the outflow of particles from the Martian atmosphere and ionosphere.

Aspera 3 has established that the solar wind penetrates through the ionosphere and very deeply into the Martian atmosphere down to an altitude of 270 kilometres. This seems to be the reason for the acceleration processes that cause the loss of atmosphere on Mars.

Original Source: ESA News Release