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.

[bd476]

NASA TV Live Online

[NinoFan]

Been watching this on NASA TV. They seem pretty darn confident which is unusual for NASA unless they're very, very sure. Cool stuff.

[edcoil]

Nope, sorry, not water, its mine. I thought I lost it.

Thanks to NASA for finding it for me.

[RightWhale]

If NASA were actually doing the Search for Life thing they always talk about they would have more biologists on staff.

[bd476]

This is still ongoing live on NASA TV

Impact on the Moon: question

Took an estimate, compared scaling to Mars, speed of objects at Mars is much slower than Earth and Moon but number of objects on Mars is higher because of proximity to Asteroid Belt.

[bd476]

Yes, they sure are confident. It's very cool.

[neodad]

Just the aliens irrigating their crops. Nothing to see here.

[HaveHadEnough]

Very cool stuff.

[Herakles]

OK, I admit it, I did take a sizable piss that last time I was there. Geeezzz, you think they would at lease put a port-a-potty up there somewhere!

[6SJ7]

I wonder if this makes it possible for those 'banyan trees' on Mars to be actual trees?!

[Historix]

Methinks we now have a possible series of landing sites for an eventual Project Constellation expedition.

[Cold Heart]

Without greenhouse gases earth would look like mars.

[Unmarked Package]

The NASA scientists estimate the new flows have a volume roughly analogous to the volume of 5 to 10 swimming pools. This is really exciting news. We can be sure the teams in charge of Mars exploration missions, currently and for the future, are eager to get more observations and analysis of these new flows.

[traderrob6]

"I did take a sizable piss that last time I was there. Geeezzz, you think they would at lease put a port-a-potty up there somewhere!"

Several hundred meters long...I'll say. Must have drank beer all the way there.

[bd476]

Rough transcription:

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Question: How long will it take moisture to evaporate? (from Houston Chronicle)

A. Two Regions

1. South of volcanic region
2. Another region - East of impact basin

How long to evaporate - billions of years ago when they had flows and channels, there were giant outflows massive catastrophic floods, greater than floods that ripped across State of Washington 13,000 years ago, more water flow then, compared to today.
Depends on how much water - a surface layer of water a couple of mm. thick would evaporate in hours/days.

Water in soil percolating up, coming up out of soil, form frost, comes out again, could be mediated by transfer process, by diffusion process...

We have colleagues in field who are doing calculations on paper, will dash out to a journal before long...

Q. How important is it for Rover to be there?

A. Very important

Q. When were the first "hey what's this moments? (San Francisco Chronicle) A. First moment was April 2005, second one was September 2005

Q. From Nature question:

What does it mean in terms of future modeling?

A. We don't know where water is coming from...

We don't have ... it wrong... constrains composition, how can we get an enhancement of heat, keep water warm...

... prior to MER I had not thought about groundwater, did calculations prior to this about acidic water...

MER data suggests that water started out being acidic then became less so...

If we have acidic water today... May change our understanding about geochemistry of groundwater...

[kinsman redeemer]

IMHO - you are looking at a slide on a talus slope. Nada mas. Unexposed material is now exposed; it is unweathered and unoxidized and brighter in appearance. It is probably high in iron.

IMHO.

[bd476]

RightWhale wrote: "If NASA were actually doing the Search for Life thing they always talk about they would have more biologists on staff."

How do we know how many biologists are on staff?

[bd476]

Unmarked Package wrote:

"The NASA scientists estimate the new flows
have a volume roughly analogous to the
volume of 5 to 10 swimming pools.

This is really exciting news. We can be sure the teams in charge of Mars exploration missions, currently and for the future, are eager to get more observations and analysis of these new flows."


Thanks and agree, that it is incredibly exciting, Unmarked Package.

[RightWhale]

We could probably dig that number out of Google. There are very few. Most NASA staff would be hardware or system management and scientists. Scientists would be astronomers and geologists, maybe a few biologists. NASA itself has about 30,000 on staff. They farm out programs to universities and aerospace companies, which is where biologists might be found.

[bd476]

kinsman redeemer wrote: "IMHO - you are looking at a slide on a talus slope. Nada mas. Unexposed material is now exposed; it is unweathered and unoxidized and brighter in appearance. It is probably high in iron.

IMHO."

That's interesting, Kinsman Redeemer. :-)

If you have a few moments, it would be good to hear further about what makes you believe that. Thanks.