NASA Briefing: NASA Images Suggest Water Still Flows in Brief Spurts on Mars

NASA ^ | 6 December 2006

[bd476]

NASA Images Suggest Water Still Flows in Brief Spurts on Mars

12.06.06

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NASA photographs have revealed bright new deposits seen in two gullies on Mars that suggest water carried sediment through them sometime during the past seven years.

" These observations give the strongest evidence to date that water still flows occasionally on the surface of Mars," said Michael Meyer, lead scientist for NASA's Mars Exploration Program, Washington.

Image right: A new gully deposit in a crater in the Centauri Montes Region. Image credit: NASA/JPL/Malin Space Science Systems
+ Full image and caption

Liquid water, as opposed to the water ice and water vapor known to exist at Mars, is considered necessary for life. The new findings heighten intrigue about the potential for microbial life on Mars. The Mars Orbiter Camera on NASA's Mars Global Surveyor provided the new evidence of the deposits in images taken in 2004 and 2005.

"The shapes of these deposits are what you would expect to see if the material were carried by flowing water," said Michael Malin of Malin Space Science Systems, San Diego. "They have finger-like branches at the downhill end and easily diverted around small obstacles." Malin is principal investigator for the camera and lead author of a report about the findings published in the journal Science.

The atmosphere of Mars is so thin and the temperature so cold that liquid water cannot persist at the surface. It would rapidly evaporate or freeze. Researchers propose that water could remain liquid long enough, after breaking out from an underground source, to carry debris downslope before totally freezing. The two fresh deposits are each several hundred meters or yards long.

Image left: A new gully deposit in a crater in Terra Sirenum. Image credit: NASA/JPL/Malin Space Science Systems

The light tone of the deposits could be from surface frost continuously replenished by ice within the body of the deposit. Another possibility is a salty crust, which would be a sign of water's effects in concentrating the salts. If the deposits had resulted from dry dust slipping down the slope, they would likely be dark, based on the dark tones of dust freshly disturbed by rover tracks, dust devils and fresh craters on Mars.

Mars Global Surveyor has discovered tens of thousands of gullies on slopes inside craters and other depressions on Mars. Most gullies are at latitudes of 30 degrees or higher. Malin and his team first reported the discovery of the gullies in 2000. To look for changes that might indicate present-day flow of water, his camera team repeatedly imaged hundreds of the sites. One pair of images showed a gully that appeared after mid-2002. That site was on a sand dune, and the gully-cutting process was interpreted as a dry flow of sand.

Image right: A colorized view of a new crater on the upper north flank of the Martian volcano Ulysses Patera. Image credit: NASA/JPL/Malin Space Science Systems

Today's announcement is the first to reveal newly deposited material apparently carried by fluids after earlier imaging of the same gullies. The two sites are inside craters in the Terra Sirenum and the Centauri Montes regions of southern Mars.

"These fresh deposits suggest that at some places and times on present-day Mars, liquid water is emerging from beneath the ground and briefly flowing down the slopes. This possibility raises questions about how the water would stay melted below ground, how widespread it might be, and whether there's a below-ground wet habitat conducive to life. Future missions may provide the answers," said Malin.

Besides looking for changes in gullies, the orbiter's camera team assessed the rate at which new impact craters appear. The camera photographed approximately 98 percent of Mars in 1999 and approximately 30 percent of the planet was photographed again in 2006. The newer images show 20 fresh impact craters, ranging in diameter from 7 feet (2 meters) to 486 feet (148 meters) that were not present approximately seven years earlier. These results have important implications for determining the ages of features on the surface of Mars. These results also approximately match predictions and imply that Martian terrain with few craters is truly young.

Mars Global Surveyor began orbiting Mars in 1997. The spacecraft is responsible for many important discoveries. NASA has not heard from the spacecraft since early November. Attempts to contact it continue. Its unprecedented longevity has allowed monitoring Mars for over several years past its projected lifetime.

NASA's Jet Propulsion Laboratory, Pasadena, manages the Mars Global Surveyor mission for the NASA Science Mission Directorate, Washington.

[smonk]

[RightWhale]

Whatever the number, it is a tiny fraction of what it should be. However, it should be private industry going into and developing space.

[RightWhale]

Ever read Blake?

[Unmarked Package]

Why does it appear to be a distributary on a downhill slope? " It doesn't appear to reach a flat area - atleast not from a monoscopic view of the image. Please - I am only speculating here - I hope you understand.

I certainly understand, skepticism is good. :-)

The pictures accompanying this article don't do justice to the structure of the flow. See the picture below for a better rendition.

[kinsman redeemer]

Thanks.

That image really changes the perspective, doesn't it?. The flow does appear to reach the plain below. This would explain the ditributary.

Also - I noticed in the other image that there are some examples of a normal dendritic drainage pattern on the downslope. Do you see them?

Thanks.

[Jedi Master Pikachu]

Related thread: From Young Werther.

[ex-snook]

Good one!

[Jedi Master Pikachu]

ping.

[Defiant]

Being overwhelmed by facts and opinions of professionals, it is good to resign one's fallacious position and learn from the experience.

Congratulations, you are the first on FR to ever concede thus.

[ex-snook]

Wonder what is the temperature on the surface that water flows and doesn't freeze? ????

[verum ago]

obviously the "we never saw that kind of color change" argument cannot be proof of anything (like water), it can only discredit other phenomenon
IMHO:
as for the distributary structure of the flow, that is interesting. However, it may be noteworthy that the flow is not on a surface with established drainages-- the area where the flow is appears to be a talus slope that has accumulated from countless small slides-- which could create a largely homogeneous surface shape devoid of any major topological low areas that would confine the flow within themselves. On earth these low areas are usually present from the consistent long-term action erosion (especially by water) which Mars lacks. The question is whether the local topology of that part of the talus slope contains enough vertical variation that the flow should be contained to a single channel; without regular water flow I see no reason that it should. Also, the flow appears to come from a single point, making a tributary form impossible (for lack of anything for the flow to contribute to or have contributed to it). Finally, may I suggest that if one were to take a signifcant quantity of water, say, a bucketful,and quickly dump it on a pile of dirt the water will will spread out in a distributary fashion with many rivulets. Only after there has been enough water consistently flowing (like having a garden hose issuing water onto the pile) can the flow establish a channel via erosion and contain itself within it (a more tributary from).

/shameless speculation

[kinsman redeemer]

The image to which I refer:

[bd476]

Whoa!

LOL, sorry but this is very exciting. :-)

Thank you for posting the close-up.

[RightWhale]

A few years ago, when they were seeing trees and subway systems on Mars, there were images of what could have been lava tubes that had become exposed by weathering. To me they looked like ice, not tubes but solid like ropes going here and there under the surface. Just plain ice formed under very low atmospheric pressure.

[bd476]

ex-snook wrote: "Wonder what is the temperature on the surface that water flows and doesn't freeze? ????"

From the NASA News conference, what I believe they said was that water on Mars percolates up then freezes at night, then melts in the Mars daylight.

[verum ago]

hmmm that is an interesting picture

kinsman: re post # 38: yikes! stay with it-- disagreement, discussion, and skepticism all should promote thought and hopefully bring both sides of the argument closer to the truth. Like you I'm not pretending to actually know what's going on over on some planet millions of miles away, but the least we can do is speculate and criticise each other's arguments in order to enhance both our understandings of the subject.

[bd476]

Victoria Crater



Victoria Crater

This stereo view of Mars' Victoria Crater combines two of the three images taken by the High Resolution Imaging Science Experiment on NASA's Mars Reconnaissance Orbiter. A red-colored image was acquired with the orbiter pointed 3.84 degrees to the west and a blue-colored one with the orbiter pointed 16.2 degrees to the west.

For a 3-D view of the topography, view this image through glasses with a red filter for your left eye, and a blue or blue-green filter for your right eye. The difference in viewing angle between the two images is about 12 degrees, which is greater than the convergence angle between the left and right eyes of humans while viewing distant objects, so the vertical relief appears much steeper than is actually the case. While some of the cliffs around the crater are in fact vertical, the slopes below the cliffs are no steeper than 30 degrees.

Images from the High Resolution Imaging Science Experiment and additional information about the Mars Reconnaissance Orbiter are available online at: http://www.nasa.gov/mro.

Image credit: NASA/JPL-Caltech/University of Arizona

Victoria Crater

[RightWhale]

speculate and criticise

I, too, am here for that to a degree, but more because the MSM or some NASA spokesman or Lib Prof somewhere will eventually get around to saying something outrageous about what NASA should do and I hope that can be caught and destroyed before it gets embedded in some totally ill-advised national policy or gets taught in the public school system.

[verum ago]

I, too, am here for that to a degree, but more because the MSM or some NASA spokesman or Lib Prof somewhere will eventually get around to saying something outrageous about what NASA should do and I hope that can be caught and destroyed before it gets embedded in some totally ill-advised national policy or gets taught in the public school system.

that too, of course. (This is an overall political forum, afterall.)

Viva FreeRepublic!

[Strategerist]

I hope that can be caught and destroyed before it gets embedded in some totally ill-advised national policy or gets taught in the public school system.

One thing I've been confused deeply by on FR is exactly whether people are somehow fearful or feel disdain to the idea of life on other planets and how that ties into creationism.