Mars Rover Yielding New Clues While Lodged In Martian Soil

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ScienceDaily (June 28, 2009) — NASA's Mars rover Spirit, lodged in Martian soil that is causing traction trouble, is taking advantage of the situation by learning more about the Red Planet's environmental history.

In April, Spirit entered an area composed of three or more layers of soil with differing pastel hues hiding beneath a darker sand blanket. Scientists dubbed the site "Troy." Spirit's rotating wheels dug themselves more than hub deep at the site. The rover team has spent weeks studying Spirit's situation and preparing a simulation of this Martian driving dilemma to test escape maneuvers using an engineering test rover at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
A rock seen beneath Spirit in images from the camera on the end of the rover's arm may be touching Spirit's belly. Scientists believe it appears to be a loose rock not bearing the rover's weight. While Spirit awaits extraction instructions, the rover is keeping busy examining Troy, which is next to a low plateau called Home Plate, approximately 3.2 kilometers (2 miles) southeast of where Spirit landed in January 2004.
"By serendipity, Troy is one of the most interesting places Spirit has been," said Ray Arvidson of Washington University in St. Louis. Arvidson is deputy principal investigator for the science payloads on Spirit and its twin rover, Opportunity. "We are able here to study each layer, each different color of the interesting soils exposed by the wheels."
One of the rover's wheels tore into the site, exposing colored sandy materials and a miniature cliff of cemented sands. Some disturbed material cascaded down, evidence of the looseness that will be a challenge for getting Spirit out. But at the edge of the disturbed patch, the soil is cohesive enough to hold its shape as a steep cross-section.
Spirit has been using tools on its robotic arm to examine tan, yellow, white and dark-red sandy soil at Troy. Stretched-color images from the panoramic camera show the tints best.
"The layers have basaltic sand, sulfate-rich sand and areas with the addition of silica-rich materials, possibly sorted by wind and cemented by the action of thin films of water. We're still at a stage of multiple working hypotheses," said Arvidson. "This may be evidence of much more recent processes than the formation of Home Plate...or is Home Plate being slowly stripped back by wind, and we happened to stir up a deposit from billions of years ago before the wind got to it?"
Team members from NASA's Johnson Space Center in Houston feel initial readings suggest that iron is mostly present in an oxidized form as ferric sulfate and that some of the differences in tints at Troy observed by the panoramic camera may come from differences in the hydration states of iron sulfates.
While extraction plans for the rover are developed and tested during the coming weeks, the team plans to have Spirit further analyze the soil from different depths. This research benefits from having time and power. In April and May, winds blew away most of the dust that had accumulated on Spirit's solar panels.
"The exceptional amount of power available from cleaning of Spirit's solar arrays by the wind enables full use of all of the rover's science instruments," said Richard Moddis of the Johnson team. "If your rover is going to get bogged down, it's nice to have it be at a location so scientifically interesting."
The rover team has developed a soil mix for testing purposes that has physical properties similar to those of the soil under Spirit at Troy. This soil recipe combines diatomaceous earth, powdered clay and play sand. A crew is shaping a few tons of that mix this week into contours matching Troy's. The test rover will be commanded through various combinations of maneuvers during the next few weeks to validate the safest way to proceed on Mars.
Spirit's right-front wheel has been immobile for more than three years, magnifying the challenge. While acknowledging a possibility that Spirit might not be able to leave Troy, the rover team remains optimistic. Diagnostic tests on Spirit in early June provided encouragement that the left-middle wheel remains useable despite an earlier stall.
"With the improved power situation, we have the time to explore all the possibilities to get Spirit out," said JPL's John Callas, project manager for Spirit and Opportunity. "We are optimistic. The last time Spirit spun its wheels, it was still making progress. The ground testing will help us avoid doing things that could make Spirit's situation worse."
Images and further information about Spirit and Opportunity are available at: http://marsrovers.jpl.nasa.gov and http://www.nasa.gov/rovers .
Adapted from materials provided by NASA/Jet Propulsion Laboratory.

Mars Express: Hummocky And Shallow Maunder Crater

Source:

http://www.sciencedaily.com/releases/2007/10/071016131458.htm

Science Daily — The High Resolution Stereo Camera (HRSC) on ESA’s Mars Express orbiter has obtained pictures of the Noachis Terra region on Mars, in particular, the striking Maunder crater.

Maunder crater lies at 50° South and 2° East, approximately in the center of Noachis Terra.
The impact crater, named after the british astronomer Edward W. Maunder (1851-1928), is located halfway between Argyre Planitia and Hellas Planitia on the southern Highlands of Mars.
With a diameter of 90 kilometres and a depth of barely 900 metres, the crater is not one of the largest impact craters on Mars at present, but it used to be much deeper. It has since been filled partially with large amounts of material.
The west of the crater experienced a major slope failure, during which a large landslide transported loose material eastward, to the inner parts of the crater. The edges of the crater rim that collapsed exhibit gullies which might be associated with the mass transport of the material.
The transition zone from the western rim of the crater to the rather smooth crater floor on the eastern edge shows hummocky terrain. Such terrain exhibits small, irregularly-shaped hills and valleys. The hummocky terrain in the Maunder crater was formed by deposition of landslide debris.
In the east, the crater floor is bounded by a trough, approximately 700 metres deep. The trough may be associated with a landslide on the western edge of the crater. Some gullies can be seen on the upper edge of the trough which is possible evidence for water seepage.
The small, 500 to 2500-metre long, dark features on the crater floor are eye-catching. These features are called Barchan dunes, one of the most abundant dune forms in arid environments. Dunes of this kind are also found on Earth, for example in the West-African Namib desert.
The colour scenes have been derived from the three HRSC-colour channels and the nadir channels. The perspective views have been calculated from the digital terrain model derived from the HRSC stereo channels. The anaglyph image was calculated from the nadir channels and two stereo channels, stereoscopic glasses are required for viewing. The 3-D (anaglyph) picture has been put together from several individual 3-D images of different scenes, enhancing the view over larger areas.
Note: This story has been adapted from material provided by European Space Agency.

Fausto Intilla

www.oloscience.com

Life On Mars 'Pregnancy Test' Successfully Launched

Source:

http://www.sciencedaily.com/releases/2007/09/070917112501.htm

Science Daily — Key components of a new approach to discover life on Mars were successfully launched into space Friday as part of a twelve-day, low-Earth orbit experiment to assess their survivability in the space radiation environment--a prelude future journeys to Mars.

The new approach is based on technology similar to that used in pregnancy test kits. The so-called immunoassays are embodied in the "Life Marker Chip" (LMC) experiment, which has the potential to detect trace levels of biomarkers in the Martian environment. Biomarkers are molecular fingerprints that indicate if life currently is, or ever was, present on Mars.
The LMC experiment has been proposed for the European Space Agency's ExoMars rover mission, which is planned for launch in 2013. The LMC experiment is in the development phase and is led by an international consortium with researchers including Andrew Steele, a staff member of Carnegie's Geophysical Laboratory in the United States, and scientists from the United Kingdom, The Netherlands, and Germany.
For the current mission, the consortium developed a tiny component, measuring only 1.5 inches x 1.6 inches x .5 inch ( 3.8 cm x 4.1 cm x 1.3 cm) and housing over 2000 samples, to test that the key molecular components to be used in the LMC technology can survive the rigors of space.
The experiment was launched from Baikonur Cosmodrome in Kazakhstan as part of the European Space Agency's BIOPAN-6 experiment platform. The LMC components will experience both weightlessness and the harsh space radiation environment while orbiting the Earth 180 times at an altitude of up to 190 miles (308 km) during the 11.8 day mission.
The BIOPAN-6 platform is mounted on the outside of an un-manned Russian FOTON spacecraft. Once in space the BIOPAN-6 platform will open to expose its contents directly to the space environment, testing both their resistance to space radiation and the space vacuum, before closing and returning to Earth on September 25th. The LMC components will then be taken back to laboratories in the United Kingdom and the United States to analyze the effect of the space flight.
The lead members of the consortium involved in the current mission are Deutsches Zentrum für Luft- und Raumfahrt (DLR) (Germany), Cranfield University (UK), Carnegie Institution of Washington (USA) and University of Leicester (UK).
Dr. Andrew Steele from the Carnegie Institution of Washington (USA) and one of the initial experiment proposers said, "in the USA we are currently flying related technology and components within the protected environment of the International Space Station (ISS) but this will be the first time that these types of materials will have flown unprotected in space in a manner similar to a flight to Mars."
Dr. Lutz Richter of DLR (Germany) and the principal investigator for the current experiment said, "This experiment is the culmination of a number of years of hard work and ground based tests to prove the viability of the LMC technology."
Dr. David Cullen, from Cranfield University (UK) and who leads the scientific input into the current experiment, said, "this will be our first space experiment to demonstrate our belief that immunoassay technology will have an important future role in space exploration and the search for life elsewhere in the Solar System."
Dr. Mark Sims from the University of Leicester (UK) and who heads the overall LMC project said, "this mission will be an important stepping stone in our ultimate goal of putting a LMC experiment on the surface of Mars and using it to search for evidence of Life."
A number of other people, organizations and companies have contributed to the experiment and these include Haptogen Ltd. (Aberdeen, UK), Oklahoma State University (USA), LioniX BV (Enschede, NL), Technische Universität München (Germany) and Dr Jan Toporski, formally of Christian-Albrechts-Universität zu Kiel (Germany).
*This release was adapted from a release by Cranfield Health, Cranfield University, Silsoe, Bedfordshire MK45 4DT, United Kingdom.
Note: This story has been adapted from a news release issued by Carnegie Institution.

Fausto Intilla

www.oloscience.com

Mars: Mysterious Ridges At The Mouth Of Tiu Valles

Source:

http://www.sciencedaily.com/releases/2007/09/070912111316.htm

Science Daily — Mars Express show the mouth of the Tiu Valles channel system on the red planet.

The mouth of Tiu Valles is an estuary-like landform. On Earth, an estuary is the tidal mouth of a river valley, or the end that meets the sea and fresh water comes into contact with seawater. In such an area, tidal effects are evident.
Tiu Valles is located at approximately 27° North and 330° East. The sun illuminates the scene from the North West, the lower left-hand side in the image.
Tiu Valles originates in the equatorial chaotic terrains at the mouth, at the eastern end of Valles Marineris. The morphology of this chaotic terrain is dominated by large-scale remnant massifs, which are large relief masses that have been moved and weathered as a block. These are randomly oriented and heavily eroded.
From there, the region extends to the north over a distance of 1500 km before terminating in Chryse Planitia. Along with Kasei Valles and Ares Valles, Tiu Valles is one of the major outflow channels entering the Chryse Planitia plain.
The scene in the images covers an area of approximately 140 by 80 km at the mouth of Tiu Valles. The region was made famous in 1997 when rover Sojourner of NASA’s Pathfinder mission landed about 600 km south-west of the mapped area.
Its winding, meandering ridges, bound by depressions, are eye-catching. The exact processes that formed these odd structures are unknown. One possibility is that during floods, water or water-rich surface layers came in contact with lava from the surrounding areas, which then might have led to the formation of these mysterious ridges.
The picture was taken in orbit 3103 on 10 June 2006 with a ground resolution of approximately 16 metres per pixel.
For related images see: http://www.esa.int/SPECIALS/Mars_Express/SEMWZZMPQ5F_0.html
Note: This story has been adapted from a news release issued by European Space Agency.

Fausto Intilla

www.oloscience.com

Opportunity Takes A Dip Into Victoria Crater

Source:

http://www.sciencedaily.com/releases/2007/09/070911212029.htm

Science Daily — NASA's Mars Exploration Rover Opportunity entered Victoria Crater for the first time September 11, 2007. It radioed home information via a relay by NASA's Mars Odyssey orbiter, reporting its activities for the day.

Opportunity drove far enough in -- about four meters (13 feet) -- to get all six wheels past the crater rim. Then it backed uphill for about three meters (10 feet). The driving commands for the day included a precaution for the rover to stop driving if its wheels were slipping more than 40 percent. Slippage exceeded that amount on the last step of the drive, so Opportunity stopped with its front pair of wheels still inside the crater.
"We will do a full assessment of what we learned from the drive today and use that information to plan Opportunity's descent into the crater," said John Callas, rover project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Once Opportunity begins its extended exploration inside the crater, the rover will investigate layered rocks exposed on the interior slope.
NASA's Mars Exploration Rover Opportunity entered Victoria Crater during the rover's 1,291st Martian day, or sol, (Sept. 11, 2007). The rover team commanded Opportunity to drive just far enough into the crater to get all six wheels onto the inner slope, and then to back out again and assess how much the wheels slipped on the slope.
The driving commands for the day included a precaution for the rover to stop driving if the wheels were slipping more than 40 percent. Slippage exceeded that amount on the last step of the drive, so Opportunity stopped with its front pair of wheels still inside the crater. The rover team planned to assess results of the drive, then start Opportunity on an extended exploration inside the crater.
Note: This story has been adapted from a news release issued by NASA, Jet Propulsion Laboratory.

Fausto Intilla

www.oloscience.com

Mars-Bound Phoenix Returns First Photo From Trip

Source:

http://www.sciencedaily.com/releases/2007/09/070911213517.htm

Science Daily — A camera flying aboard The University of Arizona-led Phoenix Mars Lander took its first picture during cruise and sent it back to Earth on Sept. 6. The lander's Robotic Arm Camera took the photo looking into the Robotic Arm's scoop. Both instruments are encased in a protection biobarrier, to ensure no Earth organisms are carried to Mars.

"It is a nice, clean picture with good sharp focus. One of these days it will be filled with Martian dirt," said Peter Smith, Phoenix principal investigator at the UA. "We have special pride in this, as it is a UA-German product."
The Robotic Arm Camera took an image of the Robotic Arm scoop using its red LED (Light-Emitting Diode) lamp. Human eyes see this image only in shades of gray, so the picture has been enhanced in false color to better represent what the camera sees.
Images from the Robotic Arm Camera, one of five imaging instruments on the lander, will be the only pictures taken and returned to Earth until Phoenix approaches and lands on Mars on May 25, 2008. Additional images will be taken by the Robotic Arm Camera later in the cruise stage.
The Robotic Arm Camera check was one of a series of instrument tests being completed as Phoenix cruises toward the red planet. Phoenix was about 57 million miles from Earth when the image was sent back. It is traveling at 76,000 miles per hour in relation to the sun.
On Mars, the Robotic Arm will dig trenches, scoop up soil and water-ice samples and deliver them to several instruments on the lander's deck for chemical and geological analysis.
The Robotic Arm Camera, built by the UA and Max Planck Institute, is attached to the Robotic Arm just above the scoop and will provide close-up, full-color images of the Martian surface, prospective soil and water-ice samples, samples collected in the scoop before delivery to the lander's science deck, and of the floor and side walls of the trenches. Phoenix's Robotic Arm was provided by the Jet Propulsion Laboratory, and the arm's scoop was manufactured by Honeybee Robotics of New York.
Phoenix launched from Cape Canaveral Air Force Station, Fla., on Aug. 4. It will fly to a site farther north than any previous Mars landing.
The solar-powered lander will robotically dig to underground ice and will run laboratory tests assessing whether the site could have ever been hospitable to microbial life. The instruments will also look for clues about the history of the water in the ice. They will monitor arctic weather as northern Mars' summer progresses toward fall, until solar energy fades and the mission ends. The Phoenix mission is led by Peter Smith of The University of Arizona, Tucson, with project management at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and development partnership at Lockheed Martin, Denver. International contributions are provided by the Canadian Space Agency; the University of Neuchatel, Switzerland; the Universities of Copenhagen and Aarhus, Denmark; the Max Planck Institute, Germany; and the Finnish Meteorological Institute.
Note: This story has been adapted from a news release issued by National Aeronautics And Space Administration.

Fausto Intilla

www.oloscience.com

Mars Rovers Survive Severe Dust Storms, Ready For Next Objectives

Source:

http://www.sciencedaily.com/releases/2007/09/070907165711.htm

Science Daily — Two months after sky-darkening dust from severe storms nearly killed NASA's Mars exploration rovers, the solar powered robots are awake and ready to continue their mission.
Opportunity's planned descent into the giant Victoria Crater was delayed, but now the rover is preparing to drive into the 800-meter-diameter crater (half-mile-diameter) as early as Sept. 11.
Spirit, Opportunity's rover twin, also survived the global dust storms. The rovers are 43 months into missions originally planned to last three months. On Sept. 5, Spirit climbed onto its long-term destination called Home Plate, a plateau of layered bedrock bearing clues to an explosive mixture of lava and water.
"These rovers are tough. They faced dusty winds, power starvation and other challenges -- and survived. Now they are back to doing groundbreaking field work on Mars. These spacecraft are amazing," said Alan Stern, associate administrator of NASA's Science Mission Directorate, Washington.
Victoria Crater contains an exposed layer of bright rocks that may preserve evidence of interaction between the Martian atmosphere and surface from millions of years ago, when the atmosphere might have been different from today's. Victoria is the biggest crater Opportunity has visited.
Martian dust storms in July blocked so much sunlight that researchers grew concerned the rovers' daily energy supplies could plunge too low for survival. Engineers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., put Opportunity onto a very low-energy regimen of no movement, few observations and reduced communication with Earth. Skies above both rovers remain dusty but have been clearing gradually since early August.
Dust from the sky has been falling onto both rovers' solar panels, impeding their ability to collect energy from the sun. However, beneficial wind gusts removed some of the new buildup from Opportunity almost as soon as it accumulated.
Opportunity drove to the lip of Victoria Crater in late August and examined possible entry routes. This week, Opportunity has been driving about 40 meters (about 130 feet) toward its planned entry point. The route will provide better access to a top priority target inside the crater: a bright band of rocks about 12 meters (about 40 feet) from the rim. "We chose a point that gives us a straight path down, instead of driving cross-slope from our current location," said Paolo Bellutta, a JPL rover driver plotting the route. "The rock surface on which Opportunity will be driving will provide good traction and control of its path into the crater."
For its first foray into the crater, Opportunity will drive just far enough to get all six wheels in; it will then back out and assess slippage on the inner slope. "Opportunity might be ready for that first 'toe dip' into the crater as early as next week," said JPL's John Callas, rover project manager. "In addition to the drives to get to the entry point, we still need to conduct checkouts of two of Opportunity's instruments before sending the rover into the crater."
The rover team plans to assess if dust has impaired use of the microscopic imager. If that tool is working, the team will use it to observe whether a scanning mirror for the miniature thermal emission spectrometer (Mini-TES) can function accurately. This mirror is high on the rover's camera mast. It reflects infrared light from the landscape to the spectrometer at the base of the mast, and it also can be positioned to close the hole in the mast as protection from dust. The last time the spectrometer was used, some aspects of the data suggested the instrument may have been viewing the inside of the mast instead of the Martian landscape.
"If the dust cover or mirror is no longer moving properly, we may have lost the ability to use that instrument on Opportunity," said Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the rovers' science instruments. "It would be the first permanent loss of an instrument on either rover. But we'll see."
The instrument already has provided extensive valuable information about rocks and soils in the Meridiani region where Opportunity works. "Mini-TES has told us a lot about the rocks and soils at Meridiani, but we've learned that the differences among Meridiani rocks are often too subtle for it to distinguish," Squyres said. "The same instrument on Spirit, at Gusev Crater, has a much more crucial role for us at this point in the mission because there is such diversity at Gusev." Researchers will rely heavily on a different type of instrument, Opportunity's alpha particle X-ray spectrometer, for analysis of rocks at the bright-band target layer in the crater.
The Jet Propulsion Laboratory manages the Mars Exploration Rover project for NASA's Science Mission Directorate. For images and information about the rovers, visit: http://www.nasa.gov/rovers.
Note: This story has been adapted from a news release issued by NASA/Jet Propulsion Laboratory.

Fausto Intilla
www.oloscience.com

Up, Up And Away -- To Venus

Source:

http://www.sciencedaily.com/releases/2007/08/070829170644.htm

Science Daily — Scientists hope to learn more about climate changes here on Earth by studying Venus. A prototype balloon could eventually study the planet’s surface and examine its atmosphere and the bizarre winds and chemistry within it. A team of JPL, ILC Dover and NASA Wallops Flight Facility engineers designed, fabricated and tested the balloon.

Slightly smaller than Earth, Venus is often regarded as Earth's sister planet. Both have similar densities, chemical compositions and gravities. However, its atmosphere is nearly 100 times thicker than Earth's, which causes blazing temperatures at the surface. By flying in the cool skies above Venus, the balloons would avoid that environment.
"The surface is hot enough to melt lead, which is why we can't study it for long from a lander," said Kevin Baines, JPL principal investigator for a proposed mission to Venus. "Without extreme and costly refrigeration methods, a lander would cook at those temperatures in just a few hours, but a balloon can stay in a benign environment, studying the planet for days, weeks or even months."
The spherical balloon, 18 feet in diameter, is about the size of an inflatable children's jumper. Its aluminum coating reflects sunlight to protect the balloon from becoming too hot as it flies in Venus’ upper atmosphere. Its outer transparent layer of the balloon is made of polytetrafluorethylene, also known as Teflon, the non-stick material found in cookware and on clothing. The material is highly resistant to the sulfuric acid found in clouds surrounding Venus. “The sun shines through the Teflon and reflects off the aluminum, and that keeps the balloon from overheating,” said Jeff Hall, JPL's lead balloon engineer.
The balloon's second layer has a mylar film similar to those shiny helium balloons found in a grocery store. The mylar is used to prevent gas from leaking out. The next layer is made of a Vectran fabric that provides the strength to keep the balloon from bursting due to internal pressure. The innermost layer has a polyurethane coating that enables all sections of the balloon to be glued together.
More details about the design, fabrication and testing of the balloon are reported in a paper published in the journal Advances in Space Research..
The proposed mission would have two balloons, one at a tropical latitude, the other at a polar latitude. Each helium-filled balloon would fly about 56 kilometers (about 35 miles) above Venus' oven-hot surface, in temperatures about the same as a spring afternoon in Los Angeles. It would take about four days for the helium superpressure balloons to fly completely around the planet. After the balloons are launched from Earth, they would arrive on the night side of Venus.
"The winds at that altitude are very strong, more than 320 kilometers per hour (about 200 miles an hour), and will blow the balloons around the planet," Hall said. "Engineers would not have control of where the balloons travel. Once the balloon starts flying, it is totally dependent on the winds."
Each balloon would have quite a roller coaster ride, moving up and down about a half a mile in altitude as they ride gravity waves generated by Venus’ mountainous terrain.
"This was one of the surprises of the Vega balloon mission the Soviet Union flew more than two decades ago," Baines said. "Enormous gravity waves appear to rise up more than 30 miles into the upper atmosphere, causing unexpected depositions of energy generated at the surface and producing strong vertical movements of air. We want to ride these waves, measuring their effect on Venus' bizarre high-speed winds."
Scientists believe the Venus balloons could also help us learn more about climate changes here on Earth. “Venus is a place where global warming has gone amuck,” Hall said. “It’s about the same size as our planet, but the surface is about 900 degrees Fahrenheit, and we want to find out why.”
Scientific instruments aboard the balloons would analyze the composition of Venus' atmosphere. The pressure cooker atmosphere around Venus quickly changes and is filled with specific gases, such as helium and neon, which do not interact chemically with other materials, allowing researchers to trace the formation of Venus over time. Noble gases can help scientists determine the geological history of the planet, which could lead to answers about current climate changes.
"Those gases will tell us if Venus and Earth were twin planets. Indications from previous missions suggest that Venus and Earth were quite similar at the beginning," Baines said.
Various studies indicate Venus once had oceans of water much like those on Earth, but now the planet is dry. According to Baines, Venus began as an oasis with conditions favorable for life in its first billion years. "Venus now has an extreme climate. It changed from being wet and wild, to dry and dead, and it seems to have happened in the last three billion years. We'd like to find out how this global transformation happened."
The current explanation for the dry atmosphere and extremely hot surface temperature is that Venus does not have a magnetic field to provide protection from solar winds. Those winds smash into the top of the atmosphere and drag off hydrogen that is needed for water.
A payload weighing more than 40 kilograms (about 90 pounds) would fly with each balloon to help transmit data back to Earth. Included in this payload would be a flight computer, radio transmitter and 9 kilograms (20 pounds) of electric batteries to power the equipment. Also included is a suite of science instruments:
A gas chromatograph mass spectrometer to measure the amounts of gases on Venus and to sniff for volcanic smoke.
An atmospheric structure instrument would measure the pressures and temperatures of the atmosphere and the vertical winds as the balloons bob up and down. This instrument also includes a nephelometer instrument to measure the size and density of cloud particles through light reflections.
A lightning detector to measure the power and frequency of nearby lightning strikes in the atmosphere.
A microphone to record any nearby sounds in the atmosphere, including thunder.
Ground-based radio telescopes using an interferometric technique would be used to measure how each balloon moves around the atmosphere. "We'd be able to tell its velocity within one inch per second of movement over an hour," Baines said. The telescopes would also use the Doppler effect to complete a set of 3-D measurements of each balloon's movements.
The company that built the airbags for the Mars Exploration Rover mission, ILC Dover, Frederica, Del., also helped design and build the balloons. The balloons are folded into small packages to fit inside the launch rocket that also include high pressure helium tanks and valves. Once the balloons reach the planet, the heavy tanks would drop away so the balloon could float away.
The balloon mission would likely end one of two ways: it might run out of battery power, when the balloons would be unable to communicate with ground controllers, or if a balloon develops a leak, it would eventually lose altitude and overheat the payload until it stops working. Hall and his team of engineers in JPL’s Aerobot laboratory have tested the prototype and determined it can float for up to 12 days without leaking any helium gas. A 12-day flight would be long enough to allow the balloons to circumnavigate the planet three times.
Note: This story has been adapted from a news release issued by NASA/Jet Propulsion Laboratory.

Fausto Intilla

www.oloscience.com

Mars Exploration Rovers Resume Driving

Source:

http://www.sciencedaily.com/releases/2007/08/070829170103.htm

Science Daily — After six weeks of hunkering down during raging dust storms that limited solar power, both of NASA's Mars Exploration Rovers, Spirit and Opportunity, have resumed driving.

Opportunity advanced 13.38 meters (44 feet) toward the edge of Victoria Crater on Aug. 21. Mission controllers were taking advantage of gradual clearing of dust from the sky while also taking precautions against buildup of dust settling onto the rover.
"Weather and power conditions continue to improve, although very slowly for both rovers," said John Callas of NASA's Jet Propulsion Laboratory, Pasadena, Calif, project manager for the rovers. With the improved energy supplies, both rovers are back on schedule to communicate daily. Opportunity had previously been conserving energy by going three or four days between communications.
No new storms have been lifting dust into the air near either solar-powered rover in the past two weeks. Skies are gradually brightening above both Spirit and Opportunity. "The clearing could take months," said rover Project Scientist Bruce Banerdt. "There is a lot of very fine material suspended high in the atmosphere."
As that material does settle out of the air, the powdery dust is accumulating on surfaces such as the rovers' solar panels and instruments. More dust on the solar panels lessens the panels' capacity for converting sunlight to electricity, even while more sunlight is getting through the clearer atmosphere.
Opportunity's daily supply of electricity from its solar panels reached nearly 300 watt-hours on Aug. 23. That is more than twice as much as five weeks ago, but still less than half as much as two months ago. It is enough to run a 100-watt bulb for three hours.
One reason the rover team chose to drive Opportunity closer to the crater rim was to be prepared, if the pace of dust accumulation on the solar panels increases, to drive onto the inner slope of the crater. This would give the rover a sun-facing tilt to maximize daily energy supplies. The drive was also designed to check performance of the rover's mobility system, so it included a turn in place and a short drive backwards.
The next day, a favorable wind removed some dust from Opportunity's solar panels, providing a boost of about 10 percent in electric output. This forestalled the need to hurry to a sun-facing slope. The team is still excited to get Opportunity inside Victoria Crater to examine science targets on the inner slope that were identified in June, shortly before dust storms curtailed rover activities. An estimate of how soon Opportunity will enter the crater will depend on assessments in coming days of how dust may be affecting the instruments and of how much energy will be available.
On Spirit, dust on the lens of the microscopic imager has slightly reduced image quality for that instrument, although image calibration can compensate for most of the contamination effects. The team is experimenting with ways to try dislodging the dust on the lens. Spirit's solar arrays are producing about 300 watt hours per day as dust accumulation on them offsets clearing skies. Spirit drove 42 centimeters (17 inches) backwards on Aug. 23 to get in position for taking images of a rock that it had examined with its Moessbauer spectrometer. The rover team is planning additional drives for Spirit to climb onto a platform informally named "Home Plate."
Note: This story has been adapted from a news release issued by NASA/Jet Propulsion Laboratory.

Fausto Intilla

www.oloscience.com

Mars Reconnaissance Orbiter's Camera Returns More Than 3,000 Images

Source:

http://www.sciencedaily.com/releases/2007/08/070829165453.htm

Science Daily — Diagnostic tests and months of stable, successful operation have resolved concerns raised early this year about long-term prospects for the powerful telescopic camera on NASA's Mars Reconnaissance Orbiter.

The High Resolution Imaging Science Experiment (HiRISE) camera on the orbiter has now taken more than 3,000 images of Mars, resolving features as small as a desk in targeted areas covering thousands of square miles of the Martian surface. Already, this is the largest Mars data set ever acquired by a single experiment. The camera is one of six instruments on the orbiter.
During the first three months after the orbiter's primary science phase began in November, researchers saw an increase in noise and pixel dropouts in data from seven of the camera's 14 detectors. The effects on image quality were small in all but two detectors, but the trend raised concerns noted in a Feb. 7 news release .
Tests have yielded an explanation for the earlier pattern, and the camera's performance record shows the noise stopped getting worse after about three to four months of the science phase.
Alfred McEwen of the University of Arizona, Tucson, principal investigator for the camera, said, "I'm happy to report that there has been no detectable degradation over the past five months."
A team at Ball Aerospace & Technologies Corp., Boulder, Colo., designer and builder of the instrument, has used an engineering model of the camera's focal-plane system to successfully duplicate the problem. This has helped in understanding causes and in testing a procedure for warming the focal-plane electronics prior to each image. One cause is that an electrical interface lacked extra capability beyond minimum requirements. Another cause is an unexpected change in performance of another electronic component over the course of the first thousand or so large images. With pre-warming, the camera acquires good data from all detectors, though minor noise remains an issue in data from one of two channels of one detector collecting infrared imagery.
McEwen said, "Given the stability we've seen and understanding the nature of the problem, we now expect HiRISE to return high-quality data for years to come."
Images from the High Resolution Imaging Science Experiment are online at http://hirise.lpl.arizona.edu/ .
The Mars Reconnaissance Orbiter mission is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, Colo., is the prime contractor and built the spacecraft.
Additional information about the Mars Reconnaissance Orbiter is online at http://www.nasa.gov/mro .
Note: This story has been adapted from a news release issued by NASA/Jet Propulsion Laboratory.

Fausto Intilla

www.oloscience.com

Flares From Sun's Far Side May Affect Space Weather Of Inner Planets

Source:

http://www.sciencedaily.com/releases/2007/08/070824131445.htm

Science Daily — Observations of solar flares by spacecraft at Mars, Venus and the Earth show that eruptions on the far side of the Sun may affect our "space weather" back on Earth.

In December 2006, a series of solar flares produced in a single active region were observed from three different points, each approximately 120 degrees apart. The results of these observations are now presented at the European Planetary Sciences Congress, Potsdam, on Thursday 23rd August by a team of scientists from the Swedish Institute of Space Physics.
Although solar flares and solar energetic particles (SEP) have been reported many times based on Earth-orbiting satellites or other planetary spacecraft, this time scientists achieved simultaneous plasma observations using instruments aboard Mars Express, Venus Express , the SOHO solar orbiter and a GOES environmental satellite, which is in geostationary orbit around the Earth.
"These observations indicate that flare activities on the far side of the Sun may affect terrestrial space weather as a result of travelling more than 90° in both azimuthal directions in the heliosphere", said Dr Yoshifumi Futaana, one of the investigators in this study.
Another important consequence of the analysis of SEP events is the insight they can provide into the process of planetary atmospheric evolution.
During the December 2006 event, Mars Express observed an enhancement of ion (oxygen) outflow flux from the Martian atmosphere. This is the first observation of this kind and suggests that the solar extreme ultraviolet flux levels significantly affect the atmospheric loss from unmagnetized planets.
Dr Futaana explained, "This is of interest for planetary scientists because the ion outflow should play an important role on the evolution of planetary atmosphere if the flux is integrated over a geological time scale (billions of years)."
This violent solar flare event also gives us a hint to solve a mystery of missing water on Mars. Mars is believed to have possessed a large amount of water approximately 3.5-4.0 billion years ago. However, no one knows where the water has gone now. One plausible idea is that the water has escaped to space, in the evolution of the planet’s atmosphere. One of the main scientific aims of Mars Express is to measure exactly how much of this water has been lost to space.
Note: This story has been adapted from a news release issued by European Planetology Network.

Fausto Intilla

www.oloscience.com

The Highs And Lows Of Martian Water Vapour

Source:

http://www.sciencedaily.com/releases/2007/08/070824132747.htm

Science Daily — Recent observations by instruments aboard Mars Express show peculiar behaviour by water vapour in the highest and lowest regions of Mars.

Measurements of water vapour in the atmosphere of Mars by the PFS (Planetary Fourier Spectrometer) and OMEGA (Observatoire pour la Minéralogie, l’Eau, les Glaces, at l’Activité) instruments, both onboard Mars Express, give us a clear view on the seasonal behaviour of water vapour in the atmosphere of Mars. The study shows irregularities in the behaviour of water vapour, different from the global trend on Mars, in the atmosphere surrounding the Big Volcanoes and the Hellas Basin, which are respectively the highest and lowest regions on Mars.
There have been regular measurements of the behaviour of water vapour during the Martian year since the 1970s, but the complementary characteristics of these two instruments allow a comprehensive analysis of the Martian water cycle with unprecedented detail.
"For most of the year, the atmosphere on the summit of the big volcanoes is enriched in water vapour – the ratio of water vapour is much higher compared to the surrounding areas. This can be explained by upslope currents activated by the extreme topography of the region that bring up a lot of material, water vapour included, from the bottom to the summit," said Luca Maltagliati, a scientist at the Max Planck Institute for Solar System Research.
In the Hellas Basin region, the observations also showed a peculiar seasonal behaviour. While the north seems to present the same quantity of water vapour through the Martian year, the interior of the basin seems to be depleted of it in some seasons, especially if compared to the south region.
The causes for this are still being investigated but it is believed that, in this case, local circulation of the atmosphere plays an important role. In fact, Hellas itself is known to have an important part in driving the circulation of the whole Southern hemisphere of Mars. The presence of surface ice was also observed during local winter.
Results from the study will be presented by Luca Maltagliati at the European Planetary Science Congress in Potsdam on Wednesday 22nd August.
These results mark the importance of local influence on the global water cycle.
Mars Express
Mars Express is the European Space Agency's first mission to Mars. The spacecraft, which has been in orbit since December 2003, is investigating the history of water on Mars and mapping the planet in unprecedented detail.
Big Volcanoes on Mars
Tharsis Montes is a range of three volcanoes in the Tharsis region of Mars.
It consists of Ascraeus Mons (whose summit is about 18 km above Mars' mean surface level, and is 460 km in diameter), Pavonis Mons (14 km above Mars'
mean surface level) and Arsia Mons (almost 19 km high and 435 km in diameter). Another volcano, Olympus Mons (22 km high and 600km in diameter), is the tallest known mountain in the Solar System and is located northwest of the Tharsis volcanoes.
The Hellas Impact Basin
The Hellas Impact Basin, also known as the Hellas Planitia is a roughly circular impact crater located in the southern hemisphere of the planet Mars. It is the largest impact structure on the planet, with a diameter of about 2,300 km and a depth of 8 km in its lowest point) The basin is thought to have been formed during the Late Heavy Bombardment period of the Solar System, over 3.9 billion years ago, when a large asteroid impacted Mars.
Note: This story has been adapted from a news release issued by European Planetology Network.

Fausto Intilla

www.oloscience.com

Martian Life? Small Percentage Of Martian Soil Samples Could Have Biological Origin

Source:

http://www.sciencedaily.com/releases/2007/08/070824122441.htm

Science Daily — A new interpretation of data from NASA's Viking landers indicates that 0.1% of the Martian soil tested could have a biological origin.

Dr Joop Houtkooper of the University of Giessen, Germany, believes that the subfreezing, arid Martian surface could be home to organisms whose cells are filled with a mixture of hydrogen peroxide and water. In a presentation at the European Planetary Science Congress in Potsdam on Friday 24th August, Dr Houtkooper will describe how he has used data from the Gas Exchange (GEx) experiment, carried by NASA's Viking landers, to estimate the biomass in the Martian soil.
Dr Houtkooper said, "The GEx experiment measured unexplained rises in oxygen and carbon dioxide levels when incubating samples. If we assume these gases were produced during the breakdown of organic material together with hydrogen peroxide solution, we can calculate the masses needed to produce the volume of gas measured. From that, we can estimate the total biomass in the sample of Martian soil. It comes out at little more than one part per thousand by weight, comparable to what is found in some permafrost in Antarctica. This might be detectable by instruments on the Phoenix lander, which will arrive at Mars in May next year."
Dr Houtkooper and his colleague, Dr Schulze-Makuch from Washington State University, suggest that a hydrogen peroxide-water based organism would be quite capable of surviving in the harsh Martian climate where temperatures rarely rise above freezing and can reach -150 degrees Celsius at the poles.
A 60% solution of hydrogen peroxide has a freezing point of - 56.5 degrees Celsius, and the supercooling properties of such mixtures could mean that metabolic activity could survive at even lower temperatures. In addition, hydrogen peroxide-water solutions tend to attract water, which means that organisms could scavenge water molecules from the Martian atmosphere.
The downside of the water-scavenging biochemistry is that if the organisms were exposed to liquid water or warm atmospheres with high humidity, they could die through over hydration. In this case, the cell would break down, releasing oxygen. Any organic compounds could then react with the hydrogen peroxide, releasing carbon dioxide, water vapour and traces of nitrogen and minor constituents.
Dr Houtkooper said, "This hydrogen peroxide-water hypothesis could provide answers for several aspects of the Viking results that remain unexplained thirty years on. The concept of this type of life is also interesting for planners of future missions searching for life on Mars. With the long timescales involved in planning and launching Mars landers, there is a dire necessity to anticipate what kind of life we should expect to find and where we should be looking. Organisms with the hydrogen peroxide-water biochemistry would be more likely to be active in colder areas on Mars with high water vapour concentrations, as would be expected along the polar ice fringe. Looking further ahead, a sample return mission would mean that we could use all that present technology affords to analyse signs of life.
However, if the organisms were to have the chemistry we are proposing, they may well decompose completely into gases during the journey back to Earth, without leaving even a smudge behind."
The existence of organisms with the hydrogen peroxide-water chemistry would raise interesting questions about the origins of life on Earth. Dr Houtkooper does not think that it would necessarily imply independent origins for terrestrial and Martian life. "A detailed study of the biochemistry and genetics would be needed to determine whether the life forms were related. The transfer of terrestrial organisms to Mars or vice versa is a possibility given favorable conditions for the origin and persistence of life on both planets early in solar system history. The transfer of terrestrial organisms by early spacecrafts to Mars that either landed or crashed is a possibility, but it is not plausible that these organisms evolved in a few years."
Hydrogen peroxide is not unknown in the metabolic processes of terrestrial organisms. The Bombardier beetle, Brachinus Crepitans, uses a 25% solution of hydrogen peroxide to produce a steam explosion in the face of pursuing predators.
Dr Houtkooper said, "There does not appear to be any basic reason why hydrogen peroxide could not be used by living systems. While organisms on Earth have found it advantageous to include salt in their intracellular fluids, hydrogen peroxide may have been more suitable for organisms adapting to the cold, dry environment of Mars."
Background Information
NASA's Viking Mission to Mars was composed of two spacecraft, Viking 1 and Viking 2, each consisting of an orbiter and a lander. TheViking 1 Lander touched down on 20th July 1976, followed by the Viking 2 Lander 3rd September.
Each lander conducted four experiments intended to detect the presence of microbiological life on the Martian surface. Soil samples were retrieved by the landers' extendible arms.
The Gas Exchange Experiment (GEX) looked for changes in the makeup of gases in a test chamber, changes that would indicate biological activity.
The Labeled Release Experiment (LR) was set up to detect the uptake of a radioactively-tagged liquid nutrient by microbes and then analyse gases emitted by any microbes for signs of the tagging.
The Pyrolytic Release Experiment (PR) heated soil samples that had been exposed to radioactively-tagged carbon dioxide to see if the chemical had been used by organisms to make organic compounds.
The Gas Chromatograph -- Mass Spectrometer Experiment (GCMS) heated a soil sample and revealed an unexpected amount of water but failed to detect organic compounds.
Note: This story has been adapted from a news release issued by European Planetology Network.

Fausto Intilla

www.oloscience.com