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Groundwater May be Source for Erosion in Martian Gullies


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+ Figure A - (Left image) High resolution
+ Figure B - (Center image) High resolution: + Without annotation | + With annotation
+ Figure C - (Right image) High resolution

Since their discovery early during the Mars Global Surveyor's Mars Orbiter Camera investigation, as first reported in June 2000, Martian gullies have presented a puzzle for the Mars science community: what fluid was responsible for the erosion that created the channels, and where did it come from? The gullies seem to be quite young in a geologic sense (millions of years or less), yet modern and geologically-recent Mars is an extremely dry place, where water ice sublimates directly to gas when the temperature is warm enough.

Since June 2000, many hypotheses have been discussed at scientific meetings, in the scientific journals and elsewhere. The original June 2000 hypothesis held that the fluid was liquid water (either pure, salty, acidic, etc.) that came to the surface where slopes intersected conduits of groundwater. Such slopes include crater walls, valley walls, hills, massifs and crater central peaks. Later investigators explored the possibility that rather than liquid groundwater, the source was ground ice, which, under some climate conditions, melted to produce liquid runoff. Still others noted that thick mantles covered a fraction of the gully-bearing slopes, suggesting that the mantles were ancient, dust-covered snow or ice packs that might melt at the base to make liquid water runoff. Water was not the only fluid considered by various colleagues; carbon dioxide can be fluid at some pressures and temperatures. Fluid carbon dioxide was also proposed as a candidate fluidizing agent. Even dry mass movement, or land sliding, of unconsolidated granular material can exhibit some fluid-like behavior. Such mass movements were considered as an explanation for the gullies.

The presence of channels primarily formed by erosion but also displaying features representing along-channel deposition, such as levees and meanders, and terminal depositional aprons consisting of dozens to hundreds of individual flow lobes, contributed to the general acceptance of the hypothesis that gullies involved the action of liquid water.

Throughout the Mars Global Surveyor mission, the Mars Orbiter Camera team continued to image gullies at every opportunity, looking for new gullies, taking higher resolution images of previously identified gullies, and monitoring the gullies for changes that might occur. Among the results of this extensive survey are numerous examples of gullies that have geological relations to other things in their vicinity. This provides support for the hypothesis that the fluid responsible for the gullies came from beneath the ground, either as groundwater or melting of ice in the Martian subsurface. Three of the best examples are presented here.

Figure A: The first picture shows a pair of gully channels that emerge, fully-born at nearly their full width, from beneath small overhangs on the north wall of Dao Vallis. These overhangs are probably created by the presence of a hard-rock layer. Liquid, probably water, percolated through permeable layers just beneath these harder, more resistant rock layers. The arrow points to the place where one of the two neighboring channels emerges. This is a sub-frame of an image acquired on Jan. 10, 2006, located near 34.2 degrees south latitude, 268.1 degrees west longitude. The 150-meter scale bar is about 164 yards wide.

Figure B: The second picture shows a gully that formed on the wall of a crater that intersected a mare-type ridge. The term, mare, is from the dark volcanic plains of Earth's moon, for example Mare Tranquilitatis was the plain on which the Apollo 11 crew landed in 1969. The lunar maria (maria is the plural form of mare), when viewed from above, have many "wrinkle" ridges. These ridges are the surface expression of thrust faults. The mare-type ridge in the picture shown here is thus the product of faulting, as rocks on the west (left) side of the image were thrust toward the east (right). Finding a gully associated with a fault is excellent evidence for the groundwater hypothesis, because ground water percolates through cracks and pores in the ground. On Earth, springs (where groundwater comes to the surface) are often found along fault lines. What is most important about this particular Martian gully is that it occurs equatorward of 30 degrees south, which is extremely unusual. The only gully in this crater is the one associated with the fault. It is essentially the site of a spring, now dried up perhaps. This picture is a sub-frame of an image located near 29.1 degrees south latitude, 207.5 degrees west longitude, acquired on Jan. 17, 2005.

Figure C: The third picture shows a small crater on the rim of a larger crater. Only a small portion of the wall of this larger crater is captured in the image. Immediately beneath the small crater occurs a group of gullies. The presence of these gullies also supports the groundwater hypothesis because impacting meteors will fracture the rocks into which they form a crater. In this case, there would be an initial set of subsurface fractures caused by the large impact that created the original, large crater. Then, when the smaller crater formed, it would have created additional fractures in its vicinity. These extra fractures would then have provided pathways, or conduits, through which ground water would come to the surface on the wall of the larger crater, thus creating the gullies observed. One might speculate that the group of gullies was formed by the impact that made the small crater, because of the heat and fracturing of rock during the impact process. However, the gullies are much younger than the small crater; the ejecta from the small crater has been largely eroded away or buried, and the crater partially filled, while the gullies appear sharp, crisp and fresh. This is a portion of an image located near 33.9 degrees south latitude, 160 degrees west longitude, acquired on March 31, 2006.

The Mars Global Surveyor mission is managed for NASA's Office of Space Science, Washington, by NASA's Jet Propulsion Laboratory, Pasadena, Calif., a division of the California Institute of Technology, also in Pasadena. Lockheed Martin Space Systems, Denver, developed and operates the spacecraft. Malin Space Science Systems, San Diego, Calif., built and operates the Mars Orbiter Camera.

For more information about images from the Mars Orbiter Camera, see http://www.msss.com/mgs/moc/index.html.

Credit: NASA/JPL/Malin Space Science Systems


Source: NASA - Missions - Mars
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New Gully Deposit in a Crater in the Centauri Montes Region


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Figure A - High resolution: + Without annotation | + With annotation

IPB Image
+ Figure B (left image) - High resolution
Figure C (middle image) - High resolution: + Without annotation | + With annotation
+ Figure D (right image) - High resolution

Two Martian southern mid-latitude craters have new light-toned deposits that formed in gully settings during the course of the Mars Global Surveyor mission. Images from the Mars Orbiter Camera documented one case in an unnamed crater in Terra Sirenum, described in an accompanying release (click here: PIA09027). The second case, in an unnamed crater in the Centauri Montes region, east of the Hellas Basin, is described here.

Gullies were first described by Mars Orbiter Camera scientists in June 2000, and many examples were presented in our June 2000 web releases and in a paper published in the journal Science. Additional examples of these middle and high-latitude landforms can be seen among the other more than 1,600 web releases.

The new gully deposit in an unnamed crater in the Centauri Montes region is located near 38.7 degrees south latitude, 263.3 degrees west longitude. Like the new gully deposit in Terra Sirenum, this one has a light tone relative to its surroundings. It is on an equator-facing slope on which numerous narrow gully channels occur. As this slope is always in sunlight during the afternoons when Mars Global Surveyor passes overhead, the gullies always appear somewhat "washed out," just as craters on a full Moon do when viewed from Earth with a telescope.

The new, light-toned flow was first noticed by the Mars Orbiter Camera science operations team in an image acquired on Sept. 10, 2005. Re-examination of other images of this crater showed that the new deposit had actually been present on Feb. 21, 2004, when the distal (down-slope) end of the deposit was captured in other images. In February 2004, the deposit had gone unnoticed because only a small portion of it was imaged. This location was first imaged by the Mars Orbiter Camera on Aug. 30, 1999. The deposit was not present at that time. Thus, it formed between Aug. 30, 1999 and Feb. 21, 2004.

Roughly 20 percent brighter than the surface as it appeared before the flow occurred, the new deposit exhibits characteristics consistent with transport and deposition of a fluid that behaved like liquid water and likely transported some fine-grained sediment along with it. The distal end of the flow broke into several branches, or digits, and the material diverted and flowed around low obstacles. As with the example in Terra Sirenum, the depth of the flow is too thin to be measured in 1.5-meter-per-pixel (1.7-yard-per-pixel) images, so a very small volume of liquid and sediment was involved. While the material flowed and easily budded into several branches, it also must have moved slow enough to not topple over some of the low obstacles in its path.

Figure A: This figure shows the southeast wall of the unnamed crater in the Centauri Montes region, as it appeared in August 1999, and later in September 2005. No light-toned deposit was present in August 1999, but appeared by February 2004. The 300-meter scale bar represents 328 yards.

Figure B: This picture is a colorized view of the light-toned gully deposit, draped over a topographic image derived from Mars Global Surveyor's Mars Orbiter Laser Altimeter data. The color comes from a table derived from the colors of Mars as seen by the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment.

Figure C: The third figure is a mosaic of several Mars Global Surveyor images, colorized using a table derived from Mars Reconnaissance Orbiter camera color data and overlain on a sub-frame of a Mars Odyssey Thermal Emission Imaging System image. The 1-kilometer scale bar represents about 0.62 miles.

Figure D: The fourth figure is a colorized view of the light-toned gully deposit as viewed from an oblique perspective, draped over topography derived from Mars Global Surveyor's Mars Orbiter Laser Altimeter data. The color comes from a table derived from the colors of Mars as seen by the Mars Reconnaissance Orbiter camera.

The new light-toned flow, by itself, does not prove that liquid water was involved in its genesis. However, this observation and the similar light-toned flow in Terra Sirenum together show that some gully sites are indeed changing today, providing tantalizing evidence there might be sources of liquid water beneath the surface of Mars right now. In both cases, these new flows may be indicating the locations of aquifers (subsurface rocks saturated with water) that could be detected by orbiting, ground-penetrating radar systems such as the Mars Express Mars Advanced Radar for Subsurface and Ionosphere Sounding or the Mars Reconnaissance Orbiter's Mars Shallow Subsurface Radar.

The Mars Global Surveyor mission is managed for NASA's Office of Space Science, Washington, by NASA's Jet Propulsion Laboratory, Pasadena, Calif., a division of the California Institute of Technology, also in Pasadena. Lockheed Martin Space Systems, Denver, developed and operates the spacecraft. Malin Space Science Systems, San Diego, Calif., built and operates the Mars Orbiter Camera.

For more information about images from the Mars Orbiter Camera, see http://www.msss.com/mgs/moc/index.html.

Credit: NASA/JPL/Malin Space Science Systems


Source: NASA - Missions - Mars
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NASA Selects Proposals for Future Mars Missions and Studies


The linked-image press release is reproduced below:

Jan. 8, 2007
Dwayne Brown
Headquarters, Washington
202-358-1726

RELEASE: 07-03

NASA Selects Proposals for Future Mars Missions and Studies


WASHINGTON - On Monday, NASA selected for concept study development two proposals for future robotic missions to Mars. These missions would increase understanding of Mars' atmosphere, climate and potential habitability in greater detail than ever before.

In addition, NASA also will fund a U.S. scientist to participate in a proposed European Mars mission as well as fund instrument technology studies that could lead to further contributions to future Mars missions.

"These mission selections represent unprecedented future research that will lead to further advancing our knowledge and understanding of the Red Planet's climate, and atmospheric composition," said Mary Cleave, associate administrator for NASA's Science Mission Directorate, NASA Headquarters, Washington.

Each Mars mission proposal will receive initial funding of approximately $2 million to conduct a nine-month implementation feasibility study. Following these detailed mission concept studies, NASA intends to select one of the two proposals by late 2007 for full development as a Mars Scout mission. The mission developed for flight would have a launch opportunity in 2011 and cost no more than $475 million.

The selected Mars mission proposals are:

* Mars Atmosphere and Volatile Evolution mission, or MAVEN: The mission would provide first-of-its-kind measurements and address key questions about Mars climate and habitability and improve understanding of dynamic processes in the upper Martian atmosphere and ionosphere. The principal investigator is Bruce Jakosky, University of Colorado, Boulder. NASA's Goddard Space Flight Center, Greenbelt, Md., will provide project management.

* The Great Escape mission: The mission would directly determine the basic processes in Martian atmospheric evolution by measuring the structure and dynamics of the upper atmosphere. In addition, potentially biogenic atmospheric constituents such as methane would be measured. The principal investigator is Alan Stern, Southwest Research Institute, Boulder, Colorado. Southwest Research Institute, San Antonio, will provide project management.

NASA has selected Alian Wang of Washington University, St. Louis, to participate as a member of the science team for the European Space Agency's ExoMars mission. Wang will receive approximately $800,000 to study the chemistry, mineralogy and astrobiology of Mars using instrumentation on the ExoMars mission, scheduled for launch in 2013.

NASA also has selected two proposals for technology development studies that may lead to further NASA contributions to ExoMars or other Mars missions. The two technology development studies, funded for a total of $1.5 million, are:

* Urey Mars Organic and Oxidant Detector: The Urey instrument would investigate organics and oxidant materials on Mars using three complementary detection systems. The principal investigator is Jeffrey Bada, University of California at San Diego.

* Mars Organic Molecule Analyzer, or MOMA: The instrument would investigate organic molecular signatures and the environment in which they exist using a mass spectrometer and gas chromatograph. The principal investigator is Luann Becker, University of California at Santa Barbara.

These selections were judged to have the best science value among 26 proposals submitted to NASA in August 2006 in response to an open announcement of opportunity.

NASA's Mars Exploration Program seeks to characterize and understand Mars as a dynamic system, including its present and past environment, climate cycles, geology and biological potential. The Mars Exploration Program Office is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for the Mars Exploration Program, Science Mission Directorate, Washington.

For information about NASA and agency programs, visit:
http://www.nasa.gov

- end -

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


Source: NASA Press Release 07-03
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Did NASA accidentally kill life on Mars?

WASHINGTON (AP) -- Two NASA space probes that visited Mars 30 years ago may have found alien microbes on the red planet and inadvertently killed them, a scientist is theorizing.

The Viking space probes of 1976-77 were looking for the wrong kind of life, so they didn't recognize it, a geology professor at Washington State University said.

Dirk Schulze-Makuch presented his theory in a paper delivered at a meeting of the American Astronomical Society in Seattle, Washington.

The paper was released Sunday.

Based on a more expansive view of where life can take root, the paper's findings may prompt NASA to look for a different type of Martian life when its next spacecraft to visit Mars is launched later this year, one of the space agency's top scientists said.

Last month, scientists excitedly reported that new photographs of Mars showed geologic changes that suggest water occasionally flows there -- the most tantalizing sign that Mars is hospitable to life.

In the 1970s, the Viking mission found no signs of life.

But it was looking for Earth-like life, in which salt water is the internal liquid of living cells.

Given the cold dry conditions of Mars, life could have evolved on Mars with the key internal fluid consisting of a mix of water and hydrogen peroxide, said Schulze-Makuch.

That's because a water-hydrogen peroxide mix stays liquid at very low temperatures, or -68 degrees Fahrenheit, and doesn't destroy cells when it freezes. It can suck water vapor out of the air.

The Viking experiments of the 1970s wouldn't have noticed hydrogen peroxide-based life and, in fact, would have killed it by drowning and overheating the microbes, said Schulze-Makuch.

One Viking experiment seeking life on Mars poured water on soil. That would have essentially drowned hydrogen peroxide-based life, he said. And different experiment heated the soil to see if something would happen which would have baked Martian microbes.

"The problem was that they didn't have any clue about the environment on Mars at that time," Schulze-Makuch said. "This kind of adaptation makes sense from a biochemical viewpoint."

Even Earth has something somewhat related. He points to an Earth bug called the bombardier beetle that produces a boiling-hot spray that is 25 percent hydrogen peroxide as a defense weapon.

Schulze-Makuch acknowledges he can't prove that Martian microbes exist, but given the Martian environment and how evolution works, "it makes sense."

In recent years, scientists have found life on Earth in conditions that were once thought too harsh, such as an ultra-acidic river in Spain and ice-covered lakes in Antarctica.

Schulze-Makuch's research coincides with work being completed by a National Research Council panel nicknamed the "weird life" committee. The group worries that scientists may be too Earth-centric when looking for extraterrestrial life.

The problem for scientists is that "you only find what you're looking for," said Penn State University geosciences professor Katherine Freeman, a reviewer of the NRC work.

A new NASA Mars mission called Phoenix is set for launch this summer, and one of the scientists involved said he is eager to test the new theory about life on Mars.

However, scientists must come up with a way to do that using the mission's existing scientific instruments, said NASA astrobiologist and Phoenix co-investigator Chris McKay.

He said the Washington State scientist's paper piqued his interest.

"Logical consistency is nice, but it's not enough anymore," McKay said.

Other experts said the new concept is plausible, but more work is needed before they are convinced.

"I'm open to the possibility that it could be the case," said astrobiologist Mitch Sogin of the Marine Biological Lab in Woods Hole, Massachusetts.

A member of the National Research Council committee, Sogin also cautioned against "just-so stories about what is possible."

http://www.cnn.com/2007/TECH/01/07/mars.life.ap/index.html

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MRO, MGS, and Viking Views of Martian Dust Devils
Captioned Image Release No. MSSS-1 — 12 February 2007



(Left to right) (a) Syria/Claritas Dust Devil, (B) Amazonis Planitia Dust Devils, (c ) Dust Devil and Wind Gust Streaks
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(Left to right) (d) Dust-raising Event Comparison, (e) Dust Devil Features, (f) Viking 1 Dust Devil
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(g) Viking 1 Dust Devil, Animated
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Credit: NASA/JPL/Malin Space Science Systems
Click on pictures for high resolution images.


Dust devils are spinning, columnar vortices of wind that move across a landscape, pick up dust, and look somewhat like miniature tornadoes. They most commonly occur on warm, dry, nearly windless days; but they can also sometimes occur in association with a passing storm front.

Dust devils are a very common occurrence on Mars. Between 15 September 1997 and 21 January 2006, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) imaged more than 11,455 active dust devils occurring in the martian afternoon between about 1 and 3 p.m. local time. Dust devils were seen at nearly all latitudes, from 72°S to 62°N, and streaks created on the ground by passing dust devils were observed from 80°S to north of 80°N. The MGS MOC and later the Mars Reconnaissance Orbiter (MRO) Context Imager (CTX) continued observing dust devil activity through 2006, and CTX continues to watch for new dust devils every day in 2007.

Active dust devils have been observed to occur in both the northern and southern hemispheres during all seasons of the year. Most dust devils occur in mid-summer in each hemisphere. The largest dust devils, towering more than 8 kilometers (5 miles) into the sky (e.g., Wind Action--The Dust Devils of Amazonis Planitia), occur in northern Amazonis Planitia, in a region near Syria Planum and Claritas Fossae, and immediately west of Schiaparelli Basin. Contrary to a belief that was common in the Mars science community before the MGS mission, dust devils do not give rise to dust storms. In fact, when dust storms are raging, dust devils are much, much less common, especially during the dustiest times of the martian year.

The pictures presented here summarize some of the observations of dust devils obtained in recent years by the MGS MOC and MRO CTX, and by the Viking 1 orbiter nearly 30 years ago.

(a) Syria Claritas Dust Devil
This MGS MOC image shows streamers of dust being lifted from the ground and rotating around a low pressure center to form a large dust devil in the Syria/Claritas region of Mars. This picture was acquired by MOC on 31 October 2004 near 15.2°S, 108.2°W. Sunlight illuminates the scene from the upper left and north is toward the top/upper right. By knowing the elevation of the sun above the local horizon, the direction from which the sun was shining, and by measuring the length of the shadow cast by this dusty vortex, MOC scientists estimated that the dust devil at this stage of formation had reached a height of about 400 meters (~1,300 feet) above the surface. The streamers indicate that the winds in this vortex were spinning in a clockwise direction. Observations of many thousands of dust devils on Earth has demonstrated that dust devils, which are very short duration events, are not impacted by the Coriolis effect; they do not spin one way in the northern hemisphere and the other way in the southern hemisphere.

(B) Amazonis Planitia Dust Devils
MGS MOC images acquired over the past four martian years showed that hundreds of dust devils form each afternoon in northern Amazonis Planitia during the spring and summer seasons. These particular dust devils show up each year like clockwork, beginning around the start of spring and ending just after autumn arrives. The MRO CTX picked up the task of monitoring northern Amazonis dust devil activity where the MGS MOC left off. Communication with MGS was lost just days before the MRO Primary Mission began in early November 2006. From that point forward, whenever possible, the CTX team has acquired images of 30 kilometers (18.6 miles) width, some of them several hundred kilometers long, covering the areas of known dust devil activity. Also, the team has used Mars Color Imager (MARCI) daily global observations at roughly 1 km/pixel scale to monitor this area for the very largest dust devils, whenever the viewing geometry permits. This MRO CTX image shows a portion of the survey region in northwestern Amazonis as it appeared around 3 p.m. local time (on the ground) on 23 November 2006. The image center is near 36.5°N, 157.1°W, and sunlight illuminates the map-projected scene from the left/lower left. More than a dozen dust devils, of various sizes, are seen—all occurring at the same time! The dark shadows of these dust devils indicate that the larger ones tower several kilometers into the sky. North is up.

(c ) Dust Devil and Wind Gust Streaks
Dust devils commonly, although not always, create a streak on the ground as they pass over and disrupt fine coatings of dust on the surface. This MGS MOC image shows hundreds of crisscrossing dark streaks created by individual dust devils. The image also shows a suite of linear, parallel streaks formed not by dust devils, but by wind gusts. These features are located on Malea Planum near 67.2°S, 316.2°W. They were imaged by MOC during southern summer on 26 November 2003, with sunlight illuminating the scene from the upper left. North is toward the top/upper right.

(d) Dust-raising Event Comparison
This is a portion of a MGS MOC red wide angle camera image of terrain in the Noachis Terra region of Mars, as it appeared on 8 May 1999. At the time, winds were blowing across the region from the northwest, raising dust from the ground to form dust plumes, a dust storm, and near the north margin of the windy area, a dust devil. This image captures, in one moment of time, the full array of the types of dust-raising events that occur on the red planet. Over the course of the 1997–2006 MGS mission, the MOC team observed that dust is raised somewhere on the planet nearly every day. In this image, north is toward the top/upper right and sunlight illuminates the terrain from the upper left.

(e) Dust Devil Features
This picture shows two views that were acquired simultaneously by the MGS MOC on 28 December 2002. The top view is a portion of a red wide angle camera context frame; the white box shows the location of the lower image, a narrow angle camera image of a single large dust devil in northern Amazonis Planitia. The context frame shows that several other large dust devils were occurring at the same time. The narrow angle image is labeled to indicate key features, including a streak created on the surface as the dust devil traveled from the upper left (northwest) toward the lower right (southeast). The dust devil's shadow shows the tight, narrow vortex and a larger plume of dust at higher altitude above the vortex. The shadow also shows that the dust devil was bent by wind shear between points A and B. Because the angle that sunlight was impinging on the dust devil is known, the shadow can be used to measure the height and key features in the dust devil. The kink at A is about 0.64 km (2100 feet) above the surface, the bend at B is about 1.24 km (4070 ft) altitude, point C is at 1.68 km (5510 ft), and the top of the dust plume is near 2.82 km (9250 ft).

(f and g) Viking 1 Dust Devil
On 1 August 1978, the two cameras of the Viking 1 orbiter's imaging system acquired overlapping pictures of a region in Syria/Sinai that showed a light-toned columnar feature casting a shadow toward the southeast (lower right). The two images, 755A10 and 755A11, were obtained just 15 seconds apart. During that time, the bright feature and its shadow changed. The feature was a dust devil, and the Viking cameras caught it in motion. Nearly three decades later, the MGS MOC acquired an image on 22 March 2005 of the area, with the ephemeral dust devil long, long gone. During the 15 second interval between the two Viking 1 images, the dust devil moved toward the northeast (upper right) at a rate of about 18 meters (59 feet) per second. Sunlight illuminates all of the images from the upper left; north is up.

A full report about dust devils observed by the MGS MOC, containing 32 figures, was recently published by Bruce A. Cantor, Katherine M. Kanak, and Kenneth S. Edgett (2006, Mars Orbiter Camera observations of martian dust devils and their tracks (September 1997 to January 2006) and evaluation of theoretical vortex models, Journal of Geophysical Research, 111, E12002, doi:10.1029/2006JE002700).

Full-resolution views of these figures, without annotation:

o (a) Syria/Claritas Dust Devil
o (B) (the figure is not annotated)
o (c ) Dust Devil and Wind Gust Streaks
o (d) Dust-raising Event Comparison
o (e) Dust Devil Features
o (f) Viking 1 Dust Devil
o (g) (the non-annotated still frames are in (f), above)

Additional images of dust devils and dust devil streaks acquired by MGS MOC can be seen here: Dust Devils.

Citation and Credit
The image(s) and caption are value-added products. MSSS personnel processed the images and wrote the caption information.

Source: Malin Space Science Systems
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The European Space Agency (ESA) probe Rosetta, on a mission to explore the comet 67P/Churyumov-Gerasimenko in2014, has passed within 250 km of the surface of Mars.

More on this flyby, including images from Rosetta can be found in the: Rosetta - ESA's Comet Chaser Mission thread.

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Mar. 15

WASHINGTON (Reuters) - A spacecraft orbiting Mars has scanned huge deposits of water ice at its south pole so plentiful they would blanket the planet in 36 feet of water if they were liquid, scientists said on Thursday.

The scientists used a joint NASA-Italian Space Agency radar instrument on the European Space Agency Mars Express spacecraft to gauge the thickness and volume of ice deposits at the Martian south pole covering an area larger than Texas.

The deposits, up to 2.3 miles thick, are under a polar cap of white frozen carbon dioxide and water, and appear to be composed of at least 90 percent frozen water, with dust mixed in, according to findings published in the journal Science.

Scientists have known that water exists in frozen form at the Martian poles, but this research produced the most accurate measurements of just how much there is.

They are eager to learn about the history of water on Mars because water is fundamental to the question of whether the planet has ever harbored microbial or some other life. Liquid water is a necessity for life as we know it.

Characteristics like channels on the Martian surface strongly suggest the planet once was very wet, a contrast to its present arid, dusty condition.

Jeffrey Plaut of NASA's Jet Propulsion Laboratory in Pasadena, California, who led the study, said the same techniques are being used to examine similar ice deposits at the Martian north pole.

Radar observations made in late 2005 and early 2006 provided the data on the south pole, and similar observations were taken of the north pole in the past several months, Plaut said.

Plaut, part of an international team of two dozen scientists, said a preliminary look at this data indicated the ice deposits in at the north pole are comparable to those at the south pole.

SEARCH FOR LIFE

"Life as we know it requires water and, in fact, at least transient liquid water for cells to survive and reproduce. So if we are expecting to find existing life on Mars we need to go to a location where water is available," Plaut said.

"So the polar regions are naturally a target because we certainly know that there's plenty of H2O there."

Some of the new information even hints at the possible existence of a thin layer of liquid water at the base of the deposits.

But while images taken by NASA's Mars Global Surveyor spacecraft made public in December suggested the presence of a small amount of liquid water on the surface, researchers are baffled about the fate of most of the water. The polar deposits contain most of the known water on Mars.

Plaut said the amount of water in the Martian past may have been the equivalent of a global layer hundreds of meters deep, while the polar deposits represent a layer of perhaps tens of meters.

"We have this continuing question facing us in studies of Mars, which is: where did all the water go?" Plaut said.

"Even if you took the water in these two (polar) ice caps and added it all up, it's still not nearly enough to do all of the work that we've seen that the water has done across the surface of Mars in its history."

Plaut said it appears perhaps 10 percent of the water that once existed on Mars is now trapped in these polar deposits. Other water may exist below the planet's surface or perhaps some was lost into space through the atmosphere, Plaut said.

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The official ESA news story of this discovery (including images) can be found in the Mars Exprss thread: HERE.

Edited by Waspie_Dwarf
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When NASA received the first photographs from the Mars Rover they changed the color from a blue sky and brown dirt to a weird pink colored sky and red dirt . Why would they do that ? Don't they have enough credibility problems already ? Now everyone knows that they deliberately changed the color of Mars to make it appear more alien looking and to conform to it being the "Red PLanet" when it is not . Did they think that CT's would think they had really photographed the Mars pictures in the American Southwest desert I wonder ? It's bad enough that the Moon photographs look so weird . I don't think screwing with the Mars pictures was a very smart thing to do .

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When NASA received the first photographs from the Mars Rover they changed the color from a blue sky and brown dirt to a weird pink colored sky and red dirt . Why would they do that ? Don't they have enough credibility problems already ? Now everyone knows that they deliberately changed the color of Mars to make it appear more alien looking and to conform to it being the "Red PLanet" when it is not . Did they think that CT's would think they had really photographed the Mars pictures in the American Southwest desert I wonder ? It's bad enough that the Moon photographs look so weird . I don't think screwing with the Mars pictures was a very smart thing to do .

This post would be better suited to the Conspiracies section or the Extraterrestrial Life & The UFO Phenomenon (where it has been discussed ad nauseum), however as it is here I will answer it. A very small amount of research into how the cameras on these vehicles work will explain very quickly why the above statement is totally wrong.

The cameras on most NASA spacecraft only take black and white images. Colour images are made by adding together images taken through several different filters. As well as the three primary colours there are a variety of other filters ranging in wavelength from infra-red to ultra-violet. Many images will use only two filters so as to give a colour range which best differentiates different types of mineral. Many of the images are also "false-colour", processed to exaggerate colour differences, again so that differences in rock and soil type are more obvious. The up-shot of this is that most of these images are not as the human eye would see them. Spacecraft are sent to Mars and other planets with the primary purpose of returning data that has scientific value, not to return pretty pictures for the public. Sadly all this is ignored by those claiming some nefarious purpose behind NASA's motives.

NASA make all this clear, including specifying which filters images were taken with and whether the image is "true-colour" or "false-colour". These facts are totally ignore by the conspiracy theorists (as the facts tend to get in the way of a nice story) and this information is never posted on the anti-NASA conspiracy sites.

The fact that the Martian sky appears pinkish as a result of suspended dust particles has been known since Viking in 1976. Indeed it was the colour first image from Viking 1 that many of the conspiracy theorist use as their "proof" that NASA changes the colours of images. That first published image did show a blue sky. This was as a result of being published without being correctly calibrated. NASA generated a series of images very quickly in case Viking malfunctioned almost immediately. When the colour was correctly calibrated (Viking, like the Mars Exploration Rovers, carried a colour chart so that true colour could be determined) it was discovered that the sky was pink and not blue.

The fact that Mars IS the "red planet" is known by the millions of people that have ever looked at it through a telescope. Sadly the credibility problems are not with NASA but with those who claim a conspiracy where non-exists.

Now as this is the Space News section and not the correct section for this type of discussion please post any further conspiracy theory related material in the correct section of the forum.

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This post would be better suited to the Conspiracies section or the Extraterrestrial Life & The UFO Phenomenon (where it has been discussed ad nauseum), however as it is here I will answer it. A very small amount of research into how the cameras on these vehicles work will explain very quickly why the above statement is totally wrong.

The cameras on most NASA spacecraft only take black and white images. Colour images are made by adding together images taken through several different filters. As well as the three primary colours there are a variety of other filters ranging in wavelength from infra-red to ultra-violet. Many images will use only two filters so as to give a colour range which best differentiates different types of mineral. Many of the images are also "false-colour", processed to exaggerate colour differences, again so that differences in rock and soil type are more obvious. The up-shot of this is that most of these images are not as the human eye would see them. Spacecraft are sent to Mars and other planets with the primary purpose of returning data that has scientific value, not to return pretty pictures for the public. Sadly all this is ignored by those claiming some nefarious purpose behind NASA's motives.

NASA make all this clear, including specifying which filters images were taken with and whether the image is "true-colour" or "false-colour". These facts are totally ignore by the conspiracy theorists (as the facts tend to get in the way of a nice story) and this information is never posted on the anti-NASA conspiracy sites.

The fact that the Martian sky appears pinkish as a result of suspended dust particles has been known since Viking in 1976. Indeed it was the colour first image from Viking 1 that many of the conspiracy theorist use as their "proof" that NASA changes the colours of images. That first published image did show a blue sky. This was as a result of being published without being correctly calibrated. NASA generated a series of images very quickly in case Viking malfunctioned almost immediately. When the colour was correctly calibrated (Viking, like the Mars Exploration Rovers, carried a colour chart so that true colour could be determined) it was discovered that the sky was pink and not blue.

The fact that Mars IS the "red planet" is known by the millions of people that have ever looked at it through a telescope. Sadly the credibility problems are not with NASA but with those who claim a conspiracy where non-exists.

Now as this is the Space News section and not the correct section for this type of discussion please post any further conspiracy theory related material in the correct section of the forum.

Thank you for your reply but your information is incorrect . NASA deliberately altered the color of the Mars images but no one is really sure why they did it . I have read the articles and seen the photographs which confirm the fact that NASA ordered their employees to change the color shortly after receiving the Rover images . This information didn't come from conspiracy theory web sites and dosen't belong on a conspiracy theory forum because this is not a theory but rather a fact . Why NASA ordered the color of Mars changed to conform to the mistakes of science might be considered a conspiracry though so I will post the articles where you suggested . Thank you .

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For anyone interested in this conspiracy theory they will find tucker's thread here: True Color of Mars.

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First Steps to Mars


March 28, 2007: The landing site is unknown. The rockets are still on the drawing board. Some of the astronauts haven't even been born yet.

Never mind all that. NASA's journey to Mars has already begun.

The first steps are being taken onboard the International Space Station (ISS). "Astronauts are stationed on the ISS for six months at a time," says Dr. Clarence Sams, lead scientist for the ISS Medical Project at NASA's Johnson Space Center (JSC). "Coincidentally, that's about how long it takes to travel to Mars. We can't simulate every aspect of a 50 million mile journey to Mars," he says, "but there are many questions we can answer from low Earth orbit."
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Above: Humans on Mars, an artist's concept.
Credit: Pat Rawlings/SAIC and NASA. [More]


For example, what happens to food and medicine exposed to six-plus months of space travel?

Curiously, food kept in orbit seems to lose some of its nutritional impact. Post-flight tests run on astronauts show that "blood and urine markers of nutritional status didn't match expected levels of nutrients in space foods," reports Dr. Scott Smith, head JSC's Nutritional Biochemistry Laboratory. Furthermore, researchers at JSC's Pharmacotherapeutics Laboratory noticed that some medicines returned from orbit had lost their potency.

This could be a sign of radiation at work: high-speed particles of space radiation occasionally smash into nutrient or medicine molecules, perhaps damaging those molecules and preventing them from functioning properly. So far, though, it's speculation. Neither the cause of the food and medicine breakdown nor how much breakdown is occurring is yet known, say the researchers.

"We may have to come up with a plan for protecting our supplies," continues Sams. "How fast do food and medicines degrade? Are we going to have to put supplies in a radiation-shielded area for the entire trip?"

To help answer these questions, an experiment running on the ISS called Stability of Pharmacotherapeutic and Nutritional Compounds places three identical sets of food and medicine on the station. One will be returned to Earth after 6 months, the second after 12 months, and the third after 18. That way Scott M. Smith and Lakshmi Putcha, principal investigators for the project at JSC, can figure out the rate at which the foods and medicines lose their potency. This information is important because food and medicines must survive not just the six-month trip to Mars, but the full 3 years of a Mars mission. Exposure times might even be longer if mission planners decide to send cargo capsules filled with stashes of food and medicine to Mars before the crew leaves Earth.

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Above: The International Space Station. [More]


Other experiments on the ISS examine the bodies of the crew themselves, requiring them to take blood and saliva samples and sonograms while aboard the station. "There is already quite a bit of data from shuttle flights and such, but you must understand, a lot of the measurements of the past were made pre-flight and post-flight. [We] need to know what's going on in between, during the mission," Sams explains.

For example, it's well known that people lose bone and muscle mass while in weightlessness. But scientists still don't know how that loss progresses while an astronaut is in space. Is there an initial, rapid loss as the body adjusts to being in space, followed by a plateau? Or is it a steady, relentless decline? When planning on being away from Earth's gravity for 3 years or more, these questions become important.

Other questions -- such as how the body reacts to the partial gravity of the Moon or Mars -- will have to wait until NASA sends astronauts back to the Moon in the coming decade. Meanwhile, says Sams, the ISS is an excellent place to start.

Author: Patrick Barry | Production Editor: Dr. Tony Phillips | Credit: Science@NASA

____________________________________________

More Information


NASA's Future: The Vision for Space Exploration

Source: Science@NASA
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Mars Technology Is Now Benefiting Earth

03.21.07

Just as Earth-bound humans wear protective lotion to prevent sunburn, future Mars explorers will need to shield themselves against high-energy radiation from the sun and the rest of the cosmos.

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Image above:

U.S. astronaut Michael Lopez-Alegria works

outside the International Space Station in

February 2007. Just above his head and to

the left is the High-Energy Neutron Detector.

Image credit: NASA

+ View Larger Image

Of course, to do this, they need to know the amount of radiation they might encounter along the way. Thanks to an instrument recently installed on the International Space Station, they will have a pretty good idea what to expect above the Earth and on Mars.

The instrument, known as the High-Energy Neutron Detector, has been continuously monitoring radiation at Mars since 2001 on board NASA's Odyssey spacecraft. A twin instrument is now also monitoring radiation above Earth’s atmosphere on the space station. U.S. astronaut Michael Lopez-Alegria and Russian cosmonaut Mikhail Tyurin completed its installation Feb. 22, 2007.

Will Monitor Solar Radiation

"These instruments can be used to monitor the effects of the Sun's activity across the solar system," notes JPL planetary scientist Jeff Plaut, "especially during solar flares. We now have the same detector in two different places."

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Image above:

A worker at Lockheed Martin Corp. in Denver

installs the High-Energy Neutron Device on the

Odyssey spacecraft prior to its launch to Mars

in April 2001.

Image credit: NASA/JPL-Caltech/LMCO

+ View Larger Image

The instrument was built for the Odyssey spacecraft by the Russian space agency. As is often the case, two identical instruments were built -- a primary and a flight spare. One went to Mars and one stayed behind. At Mars, the device detected buried ice in Martian soil. Russian researchers then proposed installing the unused instrument on the space station.

Earth's magnetic field and atmosphere preclude using the device to measure neutrons interacting with water molecules at the surface. But the High-Energy Neutron Detector will be able to measure neutrons from the upper atmosphere.

"This is exciting because, usually, when we build a planetary detector, we build it for a specific environment," says Gaylon McSmith, Odyssey science manager. "It's not often we get to use the same instrument at both Mars and Earth."

For additional information about Odyssey and the new findings, visit: http://mars.jpl.nasa.gov/odyssey/index.html.

Source: NASA - Missions - Odyssey

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  • 2 weeks later...
Through a Telescope Darkly


Fourteen thousand feet above the vast fetch of the Pacific Ocean, Diana Blaney announces, "Guide Dog is ready. Big Dog is ready."

"Roger," says telescope operator Paul Sears. "Guide Dog is on. Big Dog is on."

So begins a night of Mars-watching at NASA's Infrared Telescope Facility atop Hawaii's dormant Mauna Kea volcano. Here, astronomers work by night to discover things that can't be seen by day. Big Dog is the software that controls the spectrometer that measures wavelengths of light. Guide Dog takes pictures that document where the telescope is pointed.

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Image above:

Marslike Vista

Except for the blue sky, the peak of Mauna
Kea, a mountain that is sacred to native
Hawaiians, with its rust-colored cinder cones
and volcanic rocks, is reminiscent of landscapes
on Mars.
Image credit: NASA/JPL-Caltech
+ View Larger Image


The All-Nighters of Science

On this night, cloud cover makes Mars-watching especially challenging. Blaney, a member of the Mars Exploration Rover science team at NASA’s Jet Propulsion Laboratory, and Sears, a year-round employee of the University of Hawaii, will spend it trying to measure about 1,000 different wavelengths of infrared light.

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Image above:

Infrared Telescope Facility

NASA's Infrared Telescope Facility has
sophisticated instruments too heavy and
bulky to be launched into space yet powerful
enough to see global features on Mars.
Image credit: NASA/JPL-Caltech
+ View Larger Image


"All molecules vibrate," says Blaney. "You can kind of think of atoms as a bunch of masses on springs. When sunlight hits them, they start vibrating at a given frequency. What we're doing is measuring that frequency."

From a distance, the IRTF resembles a cookie tin topped by a shiny, metallic dome. Heavy metal doors protect the telescope against fluctuations of light or temperature, the sworn enemies of astronomers. Anyone who has gazed into the night sky knows how hard it is to see anything with artificial light or desert thermals invading the field of view.

Making the Invisible Visible

Blaney and Sears will spend the night in a cavernous room, seated in office chairs, fiddling with control panels and computers, waiting for a break in the clouds. Blaney has waited months for one night of viewing. Even a little bit of data is better than none. She is on a mission to find minerals that tell the story of water on the Red Planet.

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Image above:

Marslike Vista

Diana Blaney describes her research on a
windy afternoon on Mauna Kea, as technicians
prepare NASA's infrared telescope for a night
of Mars watching.
Image credit: NASA/JPL-Caltech
+ View Larger Image


In particular, Blaney is searching for minerals widely found in nature in which atoms of sulfur are bound with atoms of oxygen. Sulfur is the stuff that makes matchsticks burn. Oxygen is what humans breathe. Mars has been described as a sulfate planet. On Earth, sulfur is found in deserts, left behind when water evaporates.

If humans could see the part of the electromagnetic spectrum known as infrared light, we could look at a mineral like gypsum and see that it contains water molecules. In this way, we could tell a story of environmental change.

Sulfate Planet

Like a rainbow that separates visible light into discrete bands of color, the telescope separates infrared light into individual components. "That’s how we do most of the remote sensing of Mars," says Blaney, "for mapping everything from water vapor in the atmosphere to clays on the surface."

linked-image
Image above:

Weathered Lava

Exposed to Earth's atmosphere, the weathered
volcanic rocks of Mauna Kea's gently rising
slopes turn a rusty red, much like rocks on
Mars.
Image credit: NASA/JPL-Caltech
+ View Larger Image


Spacecraft measuring infrared light at Mars have found minerals with water and sulfur at the poles and in Valles Marineris, the solar system's largest canyon.

Stream channels and rock layers bear evidence of liquid water in the past. Scientists have lots of different ideas about how it got there. Perhaps it was transported by volcanic gases, acid rain, flowing streams, glaciers, lakes, mud flows, or even oceans.

Ideal Spot for Mars-Watching

Blaney has been observing Mars at the IRTF since 1986. Besides being a great place to view Mars, the summit of Mauna Kea looks a lot like Mars. The volcano's shape, the colors of the rocks, the absence of vegetation are reminiscent of Mars.

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Image above:

Night Shift

Paul Sears works year round operating NASA's
infrared telescope. It's well known in scientific
circles that astronomers don't operate telescopes
-- the job of safely and carefully manipulating
the delicate machinery and electronic controls
is a job entrusted only to experts.
Image credit: NASA/JPL-Caltech
+ View Larger Image


"We're above most of the weather in Hawaii," says Blaney. "It's colder. It's drier. You don't get as much rain. You don't have plants, which influence how things weather."

Measured from the ocean floor, Mauna Kea is the tallest mountain on Earth, rising 10,203 meters (33,476 feet). The volcano's summit punches into the lower reaches of the stratosphere. There's not much oxygen, and when the sun sets, the temperature drops to about 35 degrees F. (2 degrees C). Given a choice between a down jacket and a heater, an astronomer will choose the down jacket. Heat causes distortions, like mirages on a desert highway.

Martian Soils and Weathering

Mauna Kea is a shield volcano. Its gently rising flanks and central peak resemble the exterior face of a warrior's shield. Like Hawaiian volcanoes, Martian volcanoes are made of a lava rock known as basalt, rich in the elements iron and magnesium and poor in silica, the most common constituent of sand.

linked-image
Image above:

Black Lava

At a relatively safe distance of about a mile
from freshly erupting lava, young lava
deposits on Hawaii's Kilauea volcano have
not yet been exposed at the surface long
enough to weather from glistening black to
rusty red.
Image credit: NASA/JPL-Caltech
+ View Larger Image


"One of the things we're trying to do," says Blaney, "is figure out how rocks made of black lava turn into the richly colored, weathered materials we see on Mars today. You can kind of compare the process of weathering on Mars to rusting a nail. That rusty material is the iron oxide that makes the surface red."

Role of Water

Blaney gestures toward mounds of reddish rocks. "Those are cinder cones. They're created when a little bit of water from rain or groundwater gets into the lava and reacts explosively."

linked-image
Image above:

Mauna Kea Coast

White, hot steam streams skyward in the
distance where lava meets the waters of the
Pacific Ocean on Hawaii.
Image credit: NASA/JPL-Caltech
+ View Larger Image


Given the presence of water in the past, scientists wonder if Mars could have supported life. They also wonder if Mars has enough water ice to sustain human exploration.

"There have been times up there on Mauna Kea," says Blaney, "when the sky has been so dark, I could see Halley's Comet with my own eyes or see the Milky Way in great detail. The stars up there are just different. It's like being in a different world."

For additional information about Mars, visit: http://mars.jpl.nasa.gov/index.html.


Source: NASA - Missions -Mars]
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  • 3 weeks later...
Canadians Teaming Up to Develop Mars Mission Concepts


The Canadian Space Agency (CSA) press release is reproduced below:

Longueuil, Quebec, April 24, 2007 – When a mission to Mars is being developed, mission planners must consider many factors. Space technology advances, scientific needs and objectives, how to deal with distance, communications delays, and landing through the thin Martian atmosphere–all this must converge into a useful, workable mission concept. Canadian companies and researchers are part of an international drive to respond to these and other challenges.

Today, the Canadian Space Agency announced the funding of five teams selected to develop their Mars mission concept proposals. Each team is entitled to a maximum of $250,000 to develop the concept of a scientific mission to Mars, including its moons.

Team members are scientists at universities and companies across Canada and their technologies and concepts include
  • A radar satellite to study the geology of Mars
  • A rover to search for water erosion and subsurface water that uses a retractable sky camera to see around obstacles
  • An orbiter to study the composition and climate of the Martian atmosphere
  • A nanosatellite to map Mars' remnant magnetic field in the south
  • A mission to learn more about the origin, composition, and structure of Phobos, one of Mars' two moons

As we learn more about the evolution of Mars and compare it with that of Earth, we gain profound insight into the development of life-sustaining planets. The Red Planet's weathered surface may yield clues about the history of liquid water and life on Mars and provide evidence of any current microorganisms. Assessing the planet's habitability for possible human expedition crews is an equally important task for the survey of resources on Mars.

While the projects advance Canadian research on planetary exploration science and technology, they also help position Canada's space community among international mission developers. While there is no commitment to developing the proposals beyond the first phase, the Mars mission concepts will be evaluated further by the Agency.

Details of the five proposals are presented in a backgrounder.

About the Canadian Space Agency

Established in 1989, the CSA coordinates all civil space-related policies and programs on behalf of the Government of Canada. The CSA directs its resources and activities through four key thrusts: earth observation, space science and exploration, satellite communications, and space awareness and learning. By leveraging international cooperation, the CSA generates world-class scientific research and industrial development for the benefit of humanity.

For more information:
Julie Simard
Media Relations and Information Services
Canadian Space Agency
Telephone: (450) 926-4370
www.space.gc.ca

Source: CSA Press Release
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Team members are scientists at universities and companies across Canada and their technologies and concepts include

A radar satellite to study the geology of Mars

A rover to search for water erosion and subsurface water that uses a retractable sky camera to see around obstacles

An orbiter to study the composition and climate of the Martian atmosphere

A nanosatellite to map Mars' remnant magnetic field in the south

A mission to learn more about the origin, composition, and structure of Phobos, one of Mars' two moons

and some ambititous concepts indeed, considering how good they make robotic arms and other ISS contributions I am eager to see what got in mind for big red....B

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  • 3 weeks later...
A Gloomy Mars Warms Up
05.14.07


For the past 30 years, NASA scientists have been using high-tech satellite equipment to study features on the face of Mars. It appears a slight change in the planet’s surface luster has caused its temperature to rise.

To determine the extent of surface changes on Mars, scientists took images from the Viking (launched 1975) and Mars Global Surveyor (launched 2001) satellite missions and mapped them into a climate model developed at NASA Ames Research Center. They discovered that a wind-whipped, dusty surface has a measurable effect on the amount of sunlight that is reflected by the planet. The results of this research show that an increase in darkened surface areas may account for a one degree Fahrenheit rise in the surface air temperature of the planet.

linked-image


Changes in the surface albedo (A) of Mars over a 20 year period. Blue areas indicate regions that have darkened and yellow areas indicate regions that have brightened. Changes are superimposed on an albedo map from 1997, derived from Mars Global Surveyor data. (Click on image for high-resolution.)

“We know that warmer temperatures and high winds are near the darkened areas where less sunlight is reflected by the surface, and cooler temperatures and low winds generally relate to brightened areas” explained Lori Fenton, the experiment’s principal investigator at NASA Ames Research Center, in California's Silicon Valley. “What we don’t understand is how these changes in the planet’s brightness affect the martian climate.”

“Albedo” is the technical term for a planet’s ability to reflect sunlight. According to scientists, variations in the planet’s albedo are generally attributed to changes in the density and distribution of dust on the surface.

Research indicates that as the dark areas on Mars expand and darken over time, its albedo decreases, and its surface air temperature rise. Large surface areas, some almost twice the size of the continent of Africa (over 34 million square miles), have been observed to darken or brighten by 10 percent or more, which speaks to the magnitude of these global surface changes.

“The coupling of these processes with albedo changes could produce a surface-atmosphere feedback loop, in which surface albedo reductions, or darkened areas, enhance the windiness and dust devil formation that produce surface changes. Increased heating near the surface leads to greater atmospheric instability,” explained Fenton.

In other words, scientists think that when surface areas darken and expand, relatively more energy from the sun is being absorbed by the surface, which causes temperatures to rise near the surface. This, in turn, produces a less stable atmosphere generating more turbulent eddies and whirling dust devils. The more dust that is redistributed to bright surfaces, the more surfaces darken and expand, which causes more sunlight to be absorbed, increased temperatures, and less stable the atmosphere, say scientists.

“In particular, the slight increase in surface air temperature is similar to climate variations seen on Earth, even though the processes involved are significantly different,” added Fenton.

Moreover, scientists suspect that a change in global surface albedo could influence the formation of dust storms on both local and global scales. They report that the surface brightening and atmospheric cooling following the 2001 global dust storm may affect the timing of future large dust storms. Research demonstrates that surface areas may brighten depending on the way dust settles, which would suppress winds and ‘dust devil’ formation, the two mechanisms potentially responsible for dust storm initiation.

“Although the events that trigger dust storms have yet to be understood, this work demonstrates that one contributing factor may be a decrease in surface albedo. Martian climate indicators, such as global dust storm occurrences, polar energy balance, and annual global-mean air temperature, are dependent on many interrelated and poorly understood processes. By investigating solely the effects of changes in surface albedo (from two very different Mars years), we have shown that albedo interacts with, and could in part drive, other climate-influencing processes on Mars,” said Fenton.

These and related studies appeared in Nature, 2007.

For further information, please visit:

http://www.nasa.gov/home

Ruth Marlaire
NASA Ames Research Center


Source: NASA - Ames Research Center - Research
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  • 4 weeks later...
Strong evidence that Mars once had an ocean


The UC Berkley press release is reproduced below:

By Robert Sanders, Media Relations | 13 June 2007

linked-image

A view of Mars as it might have appeared more than 2 billion years ago, with a low-latitude ocean filling the lowland basin that now occupies the north polar region. Topographic deformation of features that ring the basin, which are hypothesized to be shorelines formed by an ancient ocean, suggests that Mars experienced significant true polar wander--reorientation of the planet relative to its rotation axis--that brought the planet into its present rotational state. The margins of the ocean shown here account for the topographic deformation that would have resulted from this reorientation. Sinuous features near the top of the image are valleys carved by large floods that may have supplied the ocean water. The image was generated using Viking Orbiter images and topographic data from the Mars Orbiter Laser Altimeter on board the Mars Global Surveyor spacecraft.
(Taylor Perron/UC Berkeley)


BERKELEY – paper in this week's issue of Nature by University of California, Berkeley, geophysicists demolishes one of the key arguments against the past presence of large oceans on Mars.

Even from Earth, a large plain surrounding the planet's north pole looks like a sediment-filled ocean basin. In the 1980s, Viking spacecraft images revealed two possible ancient shorelines near the pole, each thousands of kilometers long with features like those found in Earth's coastal regions. The shorelines - Arabia and the younger Deuteronilus - date from between 2 and 4 billion years ago.

In the 1990s, however, NASA's Mars Global Surveyor mapped the Martian topography to a resolution of 300 meters, and found that the shoreline varies in elevation by several kilometers (more than a mile), rising and falling like a wave with several thousand kilometers from one peak to the next. Because shoreline elevations on Earth, measured relative to sea level, are typically constant, many experts rejected the notion that Mars once had oceans.

UC Berkeley scientists have now discovered that these undulating Martian shorelines can be explained by the movement of Mars' spin axis, and thus its poles, by nearly 3,000 kilometers along the surface sometime within the past 2 or 3 billion years. Because spinning objects bulge at their equator, this so-called "true polar wander" could have caused shoreline elevation shifts similar to those observed on Mars.

"When the spin axis moves relative to the surface, the surface deforms, and that is recorded in the shoreline," said study coauthor Michael Manga, UC Berkeley professor of earth and planetary science.

"On planets like Mars and Earth that have an outer shell, or lithosphere, that behaves elastically, the solid surface will deform differently than the sea surface, creating a non-uniform change in the topography," added primary author Taylor Perron, a former UC Berkeley graduate student now a postdoctoral fellow in Harvard University's Department of Earth and Planetary Sciences.

Perron's calculations show that the resistance of Mars' elastic crust could create several-kilometer elevation differences for features like a shoreline, in accord with topographic measurements. The Arabia shoreline varies in elevation by about 2.5 kilometers, while the Deuteronilus shoreline varies by about 0.7 kilometers.

"This is a beautiful result that Taylor got. The mere fact that you can explain a good fraction of the information about the shorelines with such a simple model is just amazing. It's something I never would have guessed at the outset," said co-author Mark Richards, professor of earth and planetary science and dean of mathematical and physical sciences at UC Berkeley.

Richards goes so far as to add, "This really confirms that there was an ocean on Mars."

Richards pointed out that the tilt of the rotation axis of a planet actually remains fixed relative to the sun, but the crust moves relative to this axis. The question remains: What caused Mars' rotation axis to move relative to the crust?

Any major shift of mass on a planet - within the mantle, or between the mantle and the crust to form a volcano, or even via impact from outer space - could cause a shift of the rotation axis because a spinning planet is most stable with its mass farthest from its spin axis. Richards has modeled true polar wander in Earth's past that was generated by the upwelling of hot mantle in the interior of the planet, which some scientists claim shifted our planet's rotation axis 90 degrees some 800 million years ago, tipping the planet on its side.

Perron, Manga, Richards and their colleagues calculate that on Mars, an initial shift of 50 degrees from today's pole, equal to about 3,000 kilometers on the surface, would be sufficient to disrupt the Arabia shoreline, while a subsequent shift of 20 degrees from today's pole, or 700 kilometers, would have altered the Deuteronilus shoreline.

Interestingly, today's pole and the two ancient poles lie in a straight line equidistant from the planet's biggest feature, the Tharsis rise, a bulge just north of the equator that contains Mars' most recent volcanic vent, Olympus Mons. Tharsis is the largest volcano in the solar system, and formed about 4 billion years ago, not long after Mars solidified. Dynamically, the relative positions of Tharsis and the pole path is exactly what would be expected for any mass shift on Mars that is smaller than the Tharsis rise, since the planet would reorient in a way that keeps Tharsis on the equator.

"This alignment is unlikely to occur by coincidence," the team wrote.

Manga has a hunch about the mass shift that precipitated the tilt of Mars' rotation axis. If a flood of water had filled the Arabia ocean about 3 billion years ago, to a depth some have calculated at up to several kilometers, that mass at the pole might have been enough to shift the pole 50 degrees to the south. Once the water disappeared, the pole could have shifted back, then shifted again by 20 degrees during the deluge that created the Deuteronilus shoreline.

Because it's unclear whether the two shorelines represent separate inundations or whether one is the receded shoreline of a larger sea, an alternative scenario features the Arabia ocean receding to the Deuteronilus shoreline, shifting the pole from 50 to 20 degrees. Then, once the Arabia ocean disappears entirely, the pole returns to its current position.

Richards is skeptical of this, however, pointing out that thermal convection within the hot interior of Mars could also have caused the poles to wander.

"There must certainly be thermal convection in Mars now because Olympus Mons had new lava flows very recently, within the last 100 million years," he said. "But the jury's still out."

Manga said, too, that the source of the water, while unknown, must have produced a deluge greater than any observed on Earth, since huge canyons are cut in the flanks of the Tharsis rise. The water may have evaporated, but it may also have sunk back into underground dikes, frozen near the surface but possibly liquid below.

The study, whose coauthors include Jerry X. Mitrovica and Isamu Matsuyama, will appear in the June 14 issue of the British journal Nature. Mitrovica, who is with the Department of Physics at the University of Toronto in Ontario, Canada, and was a visiting Miller Professor at UC Berkeley, and Matsuyama, who is with the Department of Terrestrial Magnetism at the Carnegie Institution of Washington in Washington, D.C., have developed models for the effect of polar wander and internal dynamic processes on the surface deformation of Mars.

The work is part of UC Berkeley's BioMars project, funded by NASA's Astrobiology Institute. The research also was supported by UC Berkeley's Miller Institute for Basic Research in Science, the Natural Sciences and Engineering Research Council of Canada and the NASA Mars Data Analysis Program.

Source: UC Berkley Press Release
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U of T researchers find evidence of oceans on Mars

Red planet once a blue planet



The University of Toronto press release is reproduced below:

Jun 13/07
by Karen Kelly

A team of Canadian and U.S. researchers have uncovered evidence that ragged, kilometre-high undulating features on the surface of Mars were shorelines of massive ancient oceans that once covered one-third of the planet in water.

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A view of Mars as it might have appeared more than 2 billion years ago
Taylor Perron photo


Mars’s oceanic past has been debated since Viking spacecraft images from the 1970’s pinpointed features that seemed similar to shorelines on the Earth. However, in the 1990s, NASA’s Mars Global Surveyor revealed that peaks and dips along these features had topographic differences of nearly 3 kilometres. Since old shorelines on Earth remain nearly flat relative to sea level, there was widespread skepticism that these features represented ancient shorelines. In a paper published in the June 14 edition of Nature,, the researchers found that the topography can in fact be explained by a shift in the planet’s spin axis within the past 2 to 3 billion years. This shift in the rotation pole deformed shorelines that surrounded the long-vanished Arabia and Deuteronilus oceans.

“At some point in the planet’s history, a major shift of mass caused the pole to wander about 50 degrees towards its current location and the resulting change in orientation dramatically warped the topography and the ancient shorelines,” explained U of T professor of physics Jerry Mitrovica, director of the Earth system evolution program of the Canadian Institute for Advanced Research and one of the study’s authors.

As evidence, Mitrovica points to the location of Mars’ volcano Tharsis – the largest in the solar system – a feature so massive that it will always reorient itself to sit on the planet’s equator. The inferred trajectory of the pole’s path perfectly preserves Tharsis’s equatorial position. “The chances of this happening randomly are less 1 in 10,000,” Mitrovica said.

The study’s lead author, Dr. Taylor Perron of Harvard University, explains that on planets such as Mars and Earth that have an outer shell, or lithosphere, a change in the spin axis can cause the solid surface to deform differently than the sea surface and this explains Mars’s warped shorelines. Perron, who completed his research while at UC Berkeley, calculated that Mars’ elastic crust could account for the kilometre-high elevation differences in the shorelines.

“What we don’t know is what caused the poles to shift on Mars and what happened to the water,” Perron said. “The ocean may have been gradually converted into water vapor, moved to higher elevations, and flowed beneath the surface. There could be a large mass of water deep within Mars.”

This study was funded by NASA, the Canadian Institute for Advanced Research and the Natural Sciences and Engineering Research Council of Canada.


Source: U of T Press Release
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NASA Research Supports Presence of Large Oceans on Early Mars


The NASA/Ames Research Center press release is reproduced below:

June 14, 2007
Michael Mewhinney
NASA Ames Research Center, Moffett Field, Calif.
Phone: 650-604-3937/9000
E-mail: mmewhinney@mail.arc.nasa.gov

RELEASE: 07_32AR


NASA Research Supports Presence of Large Oceans on Early Mars


MOFFETT FIELD, Calif. - NASA-funded astrobiologists at the University of California, Berkeley have discovered evidence supporting the presence of large oceans of liquid water on early Mars.

One of the most obvious surface features on Mars is a large plain surrounding the north pole that resembles a sediment-filled ocean basin with shoreline-like features. But the purported shoreline isn’t level, an observation that has been used as an argument against the presence of an ocean. This new study shows that the undulations can be explained by movement of Mars' spin axis, and thus its poles, and that a liquid water ocean could indeed have existed there.The scientists’ research is scheduled to be published in the June 14 issue of Nature magazine.

“This work strongly supports the idea that there were large standing bodies of water on the Martian surface,” said Carl Pilcher, director of the NASA Astrobiology Institute at NASA Ames Research Center, Moffett Field, Calif., which co-funded the study. “Interpreting this topography as an ancient northern ocean could have a great impact on current and future Mars exploration,” he added.

"When the spin axis moves relative to the surface, the surface deforms, and that is recorded in the shoreline," said study co-author Michael Manga, a professor of Earth and planetary science at UC Berkeley, and member of the NASA Astrobiology Institute Team there. "On planets like Mars and Earth that have an outer shell or lithosphere that behaves elastically, the solid surface will deform differently than the sea surface, distorting the topography," added primary author Taylor Perron, a former UC Berkeley graduate student, now a postdoctoral fellow in Harvard University's Department of Earth and Planetary Sciences. Perron's calculations show that the resistance of the elastic crust could create elevation variations for topographic features like the shoreline, in accord with observations.

Perron, Manga and their colleagues calculate that on Mars, an initial shift of 50 degrees from today's pole would be sufficient to disrupt the shoreline. Manga theorizes that the shift that precipitated the tilt of Mars' rotation axis is related to the presence (and great mass) of an ocean at one of the poles. If a flood of water had filled an ocean at the northern pole on Mars about 3 billion years ago, its mass might have been enough to shift the pole 50 degrees to the south. Once the water disappeared, the pole could have shifted back.

Manga also said the source of the water, while unknown, may have produced a flood or deluge greater than any that have been observed on Earth, evidenced by huge canyons in the flanks of the Tharsis rise, site of the solar system’s largest volcano.The water may have evaporated, but it may also have sunk back into underground dikes, frozen near the surface but possibly liquid below.

Additional coauthors of the study include Mark Richards, professor of Earth and planetary science and dean of physical sciences at UC Berkeley, Jerry Mitrovica from the Department of Physics at the University of Toronto in Ontario, Canada, and Isamu Matsuyama from the Department of Terrestrial Magnetism at the Carnegie Institution of Washington in Washington, D.C. The work is part of UC Berkeley's BioMars project, funded by NASA's Astrobiology Institute (http://cips.berkeley.edu/biomars/). The research also was supported by UC Berkeley's Miller Institute for Basic Research in Science, the Natural Sciences and Engineering Research Council of Canada, and the NASA Mars Data Analysis Program.

The NASA Astrobiology Institute (NAI), founded in 1997, is a partnership between NASA, 16 major U.S. teams, and six international consortia. NAI's goal is to promote, conduct and lead integrated multidisciplinary astrobiology research and to train a new generation of astrobiology researchers.

For more information about the NASA Astrobiology Institute, visit:


For more information about NASA and agency programs on the Web, visit:
http://www.nasa.gov/home


- end -
--------------------------------------------------------------------------------


Source: NASA/ARC Press Release 07_32AR Edited by Waspie_Dwarf
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ESA seeks candidates for simulated 'Missions to Mars' in 2008/2009


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A human mission to Mars is a bold vision for the time beyond the International Space Station

Credits: ESA


19 June 2007

ESA is preparing for future human exploration missions to Mars. We are currently looking for volunteers to take part in a 520-day simulated Mars mission.

To go to Mars is still a dream and one of the last gigantic challenges. But one day some of us will be on precisely that journey to the Red Planet. A journey with no way out once the spaceship is on a direct path to Mars.

Challenges

These men and women will have to take care of themselves for almost two years during the roundtrip. Their survival is in their own hands, relying on the work of thousands of engineers and scientists back on Earth, who made such a mission possible.

The crew will experience extreme isolation and confinement. They will lose sight of planet Earth. A radio contact will take 40 minutes to travel to us and then back to the space explorers.

A human mission to Mars is a bold vision for the time beyond the International Space Station. However, preparations have already started today. They are geared and committed to one goal: to send humans on an exploration mission to Mars, individuals who will live and work together in a spaceship for over 500 days.


Simulation

In order to investigate the human factors of such a mission ESA has teamed up with the Russian Institute of Biomedical Problems (IBMP) and will send a joint crew of six on a 520-day simulated mission to Mars.

The simulation follows the mission profile of a real Mars mission, including a exploration phase on the surface of Mars. Nutrition will be identical to that provided on board the International Space Station.

The simulations will take place here on Earth inside a special facility in Moscow. A precursor 105-day study is scheduled to start by mid-2008, possibly followed by another 105-day study, before the full 520-day study begins in late 2008 or early 2009.

ESA is looking for 12 volunteers who are ready to participate in the simulations and thereby help to support the preparations of the real thing: a mission to Mars. Four volunteers will be needed for each of the three simulations. The selection procedure is similar to that of ESA astronauts, although there will be more emphasis on psychological factors and stress resistance than on physical fitness.


Interested?

For detailed information on this Call for Candidates and for the application form please refer to:

http://www.spaceflight.esa.int/callforcandidates


Concordia

Alongside such dedicated space mission simulations, a complementary approach to understand the complexities of human health and behaviour is to look at analogue environments. These are operational environments, which, through their natural situation produce some similar constraints as for example a mission to Mars.

ESA has already been active for some years in the Antarctic Concordia research station. In support of the scientific and technical projects there, ESA is looking for one person (each year) with a medical background. The details of that Call for Candidates can also be found at the web address indicated above.

Source: ESA - News
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  • 3 weeks later...
Pathfinder and Sojourner: 10 Years Later

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On July 4, 1997, Americans got more than a fireworks show, with NASA's first successful trip back to the surface of Mars since the Viking missions of the 1970s. The Mars Pathfinder mission and its gutsy rover, Sojourner, fascinated the world as they performed nearly flawlessly on our neighboring planet.

The lander, formally named the Carl Sagan Memorial Station following its successful touchdown, and the rover, named after American civil rights crusader Sojourner Truth, both outlived their design lives — the lander by nearly three times, and the rover by 12 times.

From landing until the final data transmission on September 27, 1997, Mars Pathfinder returned more than 16,500 images from the lander and 550 images from the rover, as well as chemical analyses of rocks and soil and extensive data on winds and other weather factors. Resulting scientific findings suggested that Mars was at one time in its past warm and wet, with water existing in its liquid state and a thicker atmosphere.

Image credit: NASA

Full Size

Source: NASA - Multimedia - Image of the Day Gallery
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  • 1 month later...
Hurtling Toward Mars


August 21, 2007: By the time you finish reading this sentence, you'll be 25 miles closer to the planet Mars.

Earth and Mars are converging, and right now the distance between the two planets is shrinking at a rate of 22,000 mph--or about 25 miles per sentence. Ultimately, this will lead to a close approach in late December 2007 when Mars will outshine every star in the night sky. Of a similar encounter in the 19th century, astronomer Percival Lowell wrote the following: "[Mars] blazes forth against the dark background of space with a splendor that outshines Sirius and rivals the giant Jupiter himself."

see captionContrary to rumor, though, Mars is never going to outshine the Moon.

There is an email circulating the internet—called the "Mars Hoax" or the "Two Moons email"—claiming that Mars will soon swell as large as the full Moon, and the two will hang together side by side on the night of Aug. 27th. "Mars will be spectacular," it states. "No one alive today will ever see this again."

No one will see it, because it won't happen.

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Above: Mars, photographed by the Viking Orbiters in
the 1970s. [More]


It is true that Earth and Mars are converging--you're now 300 miles closer--but even at closest approach the two planets are separated by a gulf of tens of millions of miles. From such a distance, Mars looks like a star, an intense yet tiny pinprick of light, never a full Moon.

To appreciate the situation, think of Earth and Mars as runners on a track, with speedy Earth on the inside lane and slower Mars on the outside: diagram. Now, in August, Earth is catching up to Mars from behind. Relative speed: 22,000 mph. In December, Earth overtakes Mars, still moving rapidly but never approaching the Red Planet any nearer than the gap between lanes: about 55 million miles.

Mindful that the two planets are converging, NASA chose this time to send its Phoenix Lander to Mars. Launched in June 2007 from Cape Canaveral, Phoenix is slated to land in late May 2008 on a Martian arctic plain where Phoenix's robotic arm will dig in the dirt hunting for, among other things, habitats for microbial life. Only to Phoenix, when it gets very close to Mars next year, will the red planet actually rival the Moon in apparent size.

So … you should forget about Mars on August 27th, right?

Not so fast. While there won't be Two Moons on August 27th, there will be Two Eyes. At 3 o'clock in the morning on that date, Mars will rise in the eastern sky alongside the red giant star Aldebaran. The two red lights side-by-side will resemble two eerie, unblinking eyes. This is worth waking up for!.



If you've been following the adventures of Spirit and Opportunity, you know that Mars is currently experiencing a planet-wide dust storm. Rust-colored dust is choking the air and dimming sunlight, causing problems for the two solar-powered rovers. During the past month, they've had to "stand-down"—no roving or digging or even communicating with Earth at times—in order to conserve power. A backyard telescope pointed at Mars on August 27th may reveal vast clouds of dust partially eclipsing some of the planet's familiar surface markings. Or it may reveal a totally orange ball—that's what Mars looks like when the dust storm kicks into high gear. Take a look; every night the view improves.

You're now 1000 miles closer to the planet Mars.


Author: Dr. Tony Phillips | Production Editor: Dr. Tony Phillips | Credit: Science@NASA

____________________________________________

More Information


Mars Exploration Rovers -- get the latest news from Spirit and Opportunity

More about the Mars Hoax -- The Mars Hoax email first appeared in 2003. On August 27th of that year, Mars really did come historically close to Earth. But the email's claim that Mars would rival the Moon was grossly exaggerated. Every August since 2003, the email has staged a revival; it is as wrong now as it was then.

One version of the 2003 email stated that Mars would resemble a full Moon when viewed at 60x power through a backyard telescope. Even that is wrong: While it is true that Mars can be magnified enough to illuminate a Moon-sized patch of retina, the human brain doesn't register a Moon-sized object. The brain takes into account context and surroundings when it estimates the size of an object--hence the Moon illusion. Nothing seen through the narrow corridor of a telescope's eyepiece feels or looks as large as a full Moon.

NASA's Future: The Vision for Space Exploration

Source: Science@NASA
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  • 4 weeks later...
New Theory Explains Ice on Mars


The University of Hawaii Institute for Astronomy press release is reproduced below:

Wobbles on Mars cause ice ages that are much more dramatic than those on Earth, says astronomer Norbert Schörghofer of the University of Hawaii.

Thanks to our large, stabilizing Moon, Earth's rotation axis is always tilted by about 23 degrees. The tilt of Mars, however, can wobble by as much as10 degrees from its current 25 degrees. Wobbles cause big changes in the amount of sunlight reaching different parts of Mars, so vast amounts of ice shift between the poles and the rest of the planet every 120,000 years.

Schörghofer's new theory appears in the September 13 issue of the journal Nature.

"We expect to see two types of ground ice when the Phoenix Lander spacecraft arrives at Mars in 2008," says Schörghofer, "ice that formed on the surface and was then buried, and ice hidden in porous soil."

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The two types of ice found on Mars, by latitude. Dry soil covers both types of ice.


During the 19th century, scientists discovered that Earth experienced ice ages. In the past few years, spacecraft have discovered that ice ages also occurred on Mars, but scientists have been puzzled because more ice than expected has survived far from the polar caps. What is left is now thought to be a combination of old ice from the last major glaciation and younger ice that formed later and in a way entirely different from the way ice formed on Earth.

The new theory sheds light on the history of vast ice-rich areas, which once covered most of Mars. Around 4 to 5 million years ago, ice accumulated from extensive snowfall outside the martian polar caps. The new theory describes what happened to this ice as the rotation axis of Mars continued to wobble over the last few million years.

Surface temperature and atmospheric humidity changed because of varying sunlight. When the climate was dry, the ice receded to a greater depth or disappeared entirely except at the highest latitudes. Dust contained in retreating ice eventually covered the ice, making it no longer visible on the surface.

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The history of subsurface ice layers on Mars over the last few million years. The tilt of the rotation axis changes with time, and the planet periodically experiences dry and humid climates.


So much of this subsurface ice has been detected that its only plausible origin was thought to be massive snowfall. However, Schörghofer's theory suggests that a lot of that snowfall ice has since been lost to the atmosphere. It has been replaced by a new layer of ice, formed not from snowfall, since the climate had meanwhile turned less humid, but by diffusion of water vapor into the soil. Atmospheric vapor can freeze inside the soil and form "pore-ice," which is mainly soil with some ice in pore spaces.

As the planet's tilt toward the sun went back and forth, the climate kept changing between dry and humid, causing many cycles of ice retreat and formation. Today we are left with two kinds of ground ice: the old massive ice sheet and very recent pore-ice.

Schörghofer is part of the multidisciplinary UH Astrobiology Institute, which is sponsored by NASA and managed through the Institute for Astronomy. Its research focuses on water as the habitat of, and chemical enabler for, life.
_________________________________________________________

The NASA Astrobiology Institute (NAI), founded in 1998, is a partnership between NASA, 16 major U.S. teams, and five international consortia. NAI's goal is to promote, conduct, and lead integrated multidisciplinary astrobiology research and to train a new generation of astrobiology researchers. For more information, see http://nai.nasa.gov/.

Founded in 1967, the Institute for Astronomy at the University of Hawaii at Manoa conducts research into galaxies, cosmology, stars, planets, and the sun. Its faculty and staff are also involved in astronomy education, deep space missions, and in the development and management of the observatories on Haleakala and Mauna Kea.

Established in 1907 and fully accredited by the Western Association of Schools and Colleges, the University of Hawaii is the state's sole public system of higher education. The UH System provides an array of undergraduate, graduate, and professional degrees and community programs on 10 campuses and through educational, training, and research centers across the state. UH enrolls more than 50,000 students from Hawaii, the U.S. mainland, and around the world.

Source: IfA- Hawaii Press Release
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