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Subscribe to RSSThe Mars Rover has detected the first on-the-ground evidence of an ancient streambed. If there was water, could Mars have supported life? NBC's Tom Costello reports
A close look at pebble-filled layers of rock has convinced scientists that NASA's Curiosity rover is driving through a dried-up stream bed on Mars where water flowed vigorously billions of years ago. They say it's the kind of place that just might have supported life when the planet was young.
"This is a rock that was formed in the presence of water," Caltech's John Grotzinger, project scientist for the $2.5 billion Mars Science Laboratory mission, said today during a televised news conference at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
The evidence is in the shape, size and composition of the rocks that Curiosity came across at multiple sites during its landing on Aug. 5. Conglomerate rocks, consisting of pebbles cemented together within layers of sediment, were seen at three sites:
- Goulburn, a bedrock formation that was exposed by the blast from Curiosity's descent.
- Link, a rock outcrop that was seen once Curiosity headed out from the landing site.
- Hottah, an uplifted slab of craggy rock that was given a visual inspection two weeks ago.
Hottah in particular showed clear evidence of rounded pebbles that were too big to be smoothed by the action of the wind. Some of the rocks are as big as golf balls. The best explanation for the gravelly pebbles was that they were eroded by the vigorous flow of water, said Curiosity science team member Rebecca Williams, a senior scientist at the Arizona-based Planetary Science Institute.
The Hottah slab, which measures 4 to 6 inches (10 to 15 centimeters) thick, looks as if "somebody came along the surface of Mars with a jackhammer and lifted up a sidewalk that you might see in downtown LA, sort of like in a construction site," Grotzinger said.
NASA / JPL-Caltech / MSSS
A closeup view of the "Hottah" rock outcrop shows the characteristic pebbly rock that is associated with the action of a flowing stream. Broken surfaces of the outcrop have rounded, gravel clasts, such as the one circled in white, which is about 1.2 inches (3 centimeters) across. The rock formation was named after Hottah Lake in Canada's Northwest Territories.
The Planetary Science Institute's Rebecca Williams describes new images from Mars.
NASA / JPL-Caltech / MSSS / PSI
This set of images compares the Link outcrop of rocks on Mars (left) with similar rocks seen on Earth (right). The image of Link, obtained by NASA's Curiosity rover, shows rounded gravel fragments, or clasts, up to a couple of inches (few centimeters) wide, within the rock outcrop. In accordance with the Mars mission's tradition, Link takes its name from a rock formation in Canada's Northwest Territories.
The evidence from the ground meshes well with the evidence from orbit indicating that Curiosity is near an 11-mile-wide (18-kilometer-wide) fan of material that may have washed down a channel in ancient times, when Mars was warmer and wetter, according to William Dietrich, a planetary scientist at the University of California at Berkeley.
"These stones ... are very, very revealing to us about the process," Dietrich said. Some previous research has suggested that water flowed on Mars only for brief periods, separated by long, cold, dry spells. That scenario might not have provided enough time for life to get a foothold on the Red Planet in ancient times. But Dietrich said the patterning of the channels within the fan suggested that water streamed through the area for well beyond a thousand-year time scale.
"We can step away from the idea that there was a single burst of water ... that built it all in a day," he told reporters.
Based on the size of the gravel seen by Curiosity, Dietrich estimated that the water moved at a speed of about 3 feet (1 meter) per second, at a depth somewhere between ankle and hip deep.
"Plenty of papers have been written about channels on Mars with many different hypotheses about the flows in them," Dietrich said in a NASA news release. "This is the first time we're actually seeing water-transported gravel on Mars. This is a transition from speculation about the size of streambed material to direct observation of it."
NASA / JPL-Caltech / Univ. of Ariz.
This image shows the topography, with shading added, around the area where NASA's Curiosity rover landed. Higher elevations are colored in red, with cooler colors indicating transitions downslope to lower elevations. The map highlights an alluvial fan of material, apparently issuing from a channel named Peace Vallis. The black oval indicates the targeted landing area for the rover known as the "landing ellipse," and the cross shows where the rover actually landed.
NASA / JPL-Caltech / UC-Berkeley
This image shows a dry streambed on an alluvial fan in Chile's Atacama Desert, revealing the typical patchy, heterogeneous mixture of grain sizes deposited together. On Mars, Curiosity has seen two rock outcrops close to its Bradbury Landing site that also record a mixture of sand and pebbles transported by water. Scientists say the mixture was probably deposited along an ancient streambed.
So far, the scientists' conclusions are based exclusively on visual observations by Curiosity's high-resolution Mastcam imager. Further imagery, along with chemical readings from other instruments on the rover, will likely be used to fill out the story of the ancient stream bed, Grotzinger said.
The main goal of Curiosity's two-year primary mission is to assess how habitable Mars was in ancient times. That's why mission managers chose 96-mile-wide (154-kilometer-wide) Gale Crater as Curiosity's landing site. It has that alluvial fan, which appears to issue forth from a channel that has now officially been designated Peace Vallis. It also has a 3-mile-high (5-kilometer-high) mountain, known as Aeolis Mons or Mount Sharp, which could preserve billions of years' worth of Mars' geological record.
Grotzinger noted that the three requirements for habitability typically listed by astrobiologists are the presence of liquid water, the availability of an energy source (such as sunlight) and the presence of carbon-based compounds that can be used as the building blocks of life.
"Now we've got a hall pass for the water examination," Grotzinger joked.
Theoretically, a long-flowing stream could be a habitable environment. "It is not our top choice as an environment for preservation of organics, though," Grotzinger said in NASA's news release. "We're still going to Mount Sharp, but this is insurance that we have already found our first potentially habitable environment."
Even if the rover's instruments detect the right kinds of carbon compounds, that would not serve as confirmation of ancient life on Mars. That would "have to wait for another mission," Grotzinger said.
More from Mars Curiosity:
- See a crescent moon in Martian sky
- Curiosity touches first rock, then takes off
- Mars rover spots mini-moon's transit
- Cosmic Log archive on the Mars mission
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the dwarf planet and the search for new worlds.
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well thats all well and good, but after dec 21st? none of it will matter, 1000 years from now a new group of people will land on earth and say there used to be life on this planet,we are doomed to be just like mars is, mars used to have life and soon? earth will also be used to have life on it,not much time left on this planet, maybe 2 months maybe less, we have burnt it out,ever think that with all the pit mining that we have put the earth out of balance? all the people have also put the earth out of balance, but they dontwant to alarm the people of this planet,would cause severe panic,the aliens are here to observe the end of a planet,why there havebeen more ufo sightings,panic? you wont know when it happens, just maybe you wakeup and 2 minutes later you are being sucked out into cold space, no one can rescue this planet, it is over folks, kiss your families goodby,none of it matters anymore, your money wont help you,the green house gases are about depleted, but they the scientists wont tell you this,once again, mass panic on a world wide scale,remember whole civiliazations have vanished on earth, the myans and others,what makes us so special that it cant or wont happen,nothing,we are a experiment gone wrong,the whole worlds civilizations are doomed crime is up wars are up and daily they seem want more wars,the earth was perfectly balanced 154 millionyears ago,.now? it is out of balance and we are ripe for a asteroid hit or just spinning off into space,no matter what it is gonna happen a lot sooner than they willtell you,think of this, when a bomb explodes ? it disrupts the earths balance, the hard land that was part of a balance is disturbed,and ther is no fix for it,no one will remember you or us in a month or so,. be jsut another star that went bad.,world is over populated, and that will put this 3rd rock out of balance, so have sweet dreams, they might be your last
1) the Mayan (note spelling) civilization collapsed, but the Mayans didn't disappear.
2) Your entire post suggests that your balance is disturbed, please get professional help.
Just a comment that it's impressive how well the mission planning has worked out so far. They had downselected from over 60 sites and really seemed to have done well. It would be exciting if this went well enough so some of the other, more difficult to reach, but potentially more interesting, sites could be explored in the future.
If one was to place a wet rock in the desert and waited until it had a 0% moisture content, what tests are there to determine that the rock was ever wet? In this instance we have a photograph of pebbles carried by water and are told that water was there billions of years ago. Really? Can't the water have been there as recently as say 200 years ago? It sure looks like dried riverbeds here on Earth that just dried out this year, let alone billions of years ago.
Water-ice currently sublimates on Mars, with its 1% (of Earth's) atmosphere. After Mars lost its dynamo, billions of years ago, the solar wind began to steadily strip away its atmosphere. Curiosity has just shown evidence of the presence of liquid water for at least thousands of years. At some point, Mars' atmosphere became so thin that liquid water quickly evaporated. Now, it is so thin that it goes from a solid to a gas. There is no way that the liquid water-smoothed rock could have been formed recently.
Someday, after our ozone layer is long gone, someone will be looking at photographs of LA and wondering what we were like.
Now this is what I call news!!!!! I would rather hear about all of this, than the other trash on Earth.
No. Those little pebbles are actually a well indurated conglomerate, so no. And at 900kg, there isn't a weather system on that planet capable of blowing away the rover.
still mulling this over
Hey Alan,I am still waiting for the "shadow" in one of the photo's! lol. Great stuff Alan!keep it coming!
Love this stuff. Just wait until the rover finds a vein of gold,and there will be so many rockets headed up,and back, that it will seem like a permanent 4th of July.
A massively exciting time in NASA history! Now, if we can only get the media outlets to frontpage these stories, and page 82 politics, Earth would be a more pleasant, serene place to co-exist.
Sorry, it's mostly because Earth is not such a place, that other stories take precedence. This is not because of 'the media.'
Besides:
1. I learned when my age was in the single numbers, that most people aren't as interested in these things as I am. Live with it, learn to find it yourself, instead of waiting for the 'front page' space stories. Libraries were always my friend, the Internet is now, too.
2. Even so, there has been some mention of this in major news outlets. But don't expect in-depth coverage. See above.
Recommended, for discussion on liquid water activity on Mars: youtu.be/5O1J0OGjZEo
Despite the water, I can't help but wonder if life was ever possible on Mars. How would radiation be blocked without a large magnetic field from a large iron core? Was the atmosphere able to block enough radiation?
Just being in the Goldilocks zone with plenty of water may not be good enough. I don't know enough about biology or organic chemistry to know if life can develop in high radiation.
Don't expect it to all to have been in surface streams. If there were ever serious bodies of water on Mars (not even oceans, long-lived Great Lakes sized bodies could be adequate), they are their own radiation protection. The first few feet is as good as an atmosphere of attenuation.
And then there's the possibility of underground water, even today...
I would be interested in how they concluded, that those rocks that are too large to be moved by wind, weren't eroded by the particles which are carried by wind.
Wouldn't that erosion also wear down the larger rocks, and round out the rough edges, without having to be moved by water.
I would hope they might attempt to dislodge one of the rocks in the conglomerate to determine if the area of the rock which is embedded in the conglomerate is already smoothed and rounded, or if the embedded side is still rough and edgy.
Wind eroded rocks have more angular features. Then too, there is the sorting of a conglomerate- there is none. Conglomerates contain detrital particles of all sizes due to the high energy of the depositional environment; aolian(wind derived) sediments have a much greater sorting of the grain size.
Geologists have been interpreting wind vs water transported sediments for hundreds of years. We know how to tell the difference.
The scientist that interpreted these features is a world expert in fluvial geomorphology, which should suggest to you that he knows a lot more than just how to tell whether a particle has been transported by wind vs. water, and he has been studying the features on Mars using the incredible images that have been coming from orbiting satellites, so he knew where Curiosity might have a chance of finding such evidence. The science is so far beyond what the average American perceives is known about our solar system. This is not to disparage your comment oppie. Few people know that some scientists spend their entire lives studying how sediment particles move.
Even if the rover's instruments detect the right kinds of carbon compounds, that would not serve as confirmation of ancient life on Mars. <~~~They're right. They'd have to find an old beer can or car tire in the dried up river bed.
If water flowed on Mars, then why are there still Monkeys?
i've said it before and i'll say it again.... please put my brain in the next rover! i wanna go to MARS sooooo bad!
OMG ALIENS!! This "news" is getting really old and tired. Who cares?
I do. I find it curious that someone that didn't care would go through the effort to leave such an insipid comment. Why waste your time?
really? So you knew of this evidence before we earthlings discovered it how?
yeah right.. if there was ever life on Mars the next thing you'll tell me is L. Ron Hubbard was a science-ficton writer.. give me a break
You must've been around for billions of years to know this.
The images sent back are simply astounding. My Camera pictures are worse than THESE FROM FAR AWAY MARS.
Is that Camera for SALE ? Whats the Make and Model #?
"dried-up stream bed on Mars"
That's some very bad sad unhappy news for taxpayers. It's like they paid to get a get a Coke and the vending machine was empty. No refund. No 1-800-Iwantmymoneyback to call.
Mars was wetter when Obama took office, it has become considerably drier since, the current state of extreme dessication we see there now is all his fault. Mitt has a good plan for rehydrating the Martian middle class by decreasing taxes on the Martian elite.
1. How much did this news cost us?
2. Now that we know, what the F difference does it make to anyone living here?
1.) In the future the earth will no longer exist. This is fact.
2.) If we dont' slowly develop and explore the Universe, our life will cease to exist. This is also fact.
3.) Doesn't sound to me like it costs too much. This is opinion.
1. NASA estimates the total cost of the mission at $2.5 billion. Please remember we did NOT load that cash into a rocket and shoot it to Mars. That money is/was paid to the workers and scientists who have designed, built and launched Curiosity, and to the scientists who monitor its progress and report news like this. That is money spent here on Earth, being put back into our economy, which is what drives our economy to improve, not stagnate.
2. Barring a self-caused extinction event, humans from the Earth WILL colonize Mars in the not too distant future. Additionally, spin off technologies from missions from like this effect people everyday.
Follow up:
This isn't Columbus sailing the ocean blue looking for the Northwest Passage. We need serious, detailed examination of Mars to know how to approach living there. Did water ever flow? Could water still be there, trapped under the soil? Water is pretty important to human life, and if we can tap into domestic supplies on Mars, rather than transporting it from Earth, that will safe time, weight and money for future human explorers.
You can live selfishly in the present, or look up to the future of all of us.
Reading thru these comments makes me sad in a way. Some people are just so misinformed! Science & discovery are crucial to the present and future existence of mankind. The technology developed for these type of missions has a profound impact on current everyday applications and future technologies.
The fact that people gripe over 2.25 billion, which is a drop in the bucket, being spent on something that will probably have a direct impact on them someday one way or another is disheartening vs. the 100's of billions being spent on these useless war(s) and other careless government expenditures. Again, people gripe because they are misinformed and don't understand. I just wish the government would "carelessly" spend a great deal more into science.
Go science, it's the last great hope we have! Keep enjoying the Kardashians, Honey Boo Boos and other filth we call television these days a.k.a the dumbing down of what used to be a great country called America.
Intelligent life requires negative entropy.
God must've created that River on the 3rd day.
Should have rested, before creating man in his/her image, could have been a just bad hair day.
Re the stream bed, sure hope the mastcam takes time to LOOK for small fossils that might have been washed down into the gravel bedding. Yes, the mountain layers could also show microfossils, but, here is an excellent chance to actually DETECT the remains of past life via fossils. If we do find fossils on Mars, that proves the case for life evolving on Mars, period.
" life evolving on mars " ????? There is NO proof of life on mars, or will there ever be that it began there. Where is all the dust on the moon & mars ? Half an inch is only about 6,000 years of build up-remember the tire & foot prints ??????? DNA evolved ? Do you think you came from a rock ? Or a black man that came from an ape ? " and HE rested on the seventh day from all his works he had made."