Image courtesy Caltech/NASA
Published March 12, 2013
Long ago, Mars had the conditions and ingredients to support life.
That conclusion—the first ever made about another celestial body—was announced today by the Curiosity rover team after a wildly successful drilling campaign into what may have once been the bed of a Martian lake. (Related: "Mars Rover Curiosity Completes First Full Drill.")
"We have found a habitable environment," said John Grotzinger, project scientist for the Curiosity mission. "The water that was here was so benign and supportive of life that if a human had been on the planet back then, they could drink it."
Their finding is based in part on the discovery of both clays and sulfate minerals in the powered sample drilled out of the rock named after deceased mission project manager John Klein. Both materials only form in water, and only in water that is low in potentially life-killing acids. (Related: "Mars Rover Finds Intriguing New Evidence of Water.")
At a press conference at NASA headquarters in Washington, D.C., the team also announced that simple organics had been detected by the Sample Analysis at Mars (SAM) instrument.
Principal investigator Paul Mahaffy said, however, that it remained unclear if the organics are of purely Martian origin or if they were formed by interactions with organics inadvertently brought from Earth by Curiosity. (Related: "Mars Rover Detects Simple Organic Compounds.")
The low depression where Curiosity has been exploring for several months is called Yellowknife Bay, and Grotzinger and others described it excitedly as a "jackpot" for their mission.
Curiosity will drill another hole in the John Klein rock in May, after communication between Earth and Mars is safely restored following a conjunction—when the sun will come between the two planets.
The head of the NASA Science mission directorate, John Grunsfeld, said at the end of the press conference that he felt "giddy" about the results and the possibility that Curiosity is now drilling in an ancient lakebed.
"This has been a huge science question: Did Mars once have a habitable environment?" Grunsfeld said. "Now we have an answer."
Although the determination of "habitability" is considered a major breakthrough, it does not mean that Mars was necessarily once home to microbes or any other form of life.
But having earlier determined that Mars was once much wetter and warmer, and now that it had the kinds of minerals that are formed only in the kind of water that can support life, the possibility that organisms once existed on the planet is certainly greater.
Gray Is Good
The initial breakthrough came when the Chemical and Mineralogy Instrument (CheMin) detected a type of clay called smectite at the John Klein site, and found it in large concentrations. It is the kind of clay that—on Earth—often forms in still, basic (non-acidic) water.
Not only is the smectite discovery a scientific gold mine because of those qualities, said CheMin principal investigator David Blake, but the mineral is also capable of preserving ancient organic compounds, which are the building blocks of life.
The Curiosity team had grown excited about the drilling results as soon as they saw that the inside of the rock wasn't red, but rather was gray. The red color of Mars is a function of the presence of iron compounds, which are acidic and can destroy traces of organics.
"A gray Mars suggests habitability," Grotzinger said.
The SAM instrument has also found evidence in the drill sample of life-supporting carbon in the form of carbon dioxide. If the carbon was available to any potential living organisms, that would lend further support for the habitability of ancient Mars. (Related: "Meet One of Mars Rover Curiosity's Earthbound Twins.")
Asked if this period of habitability coincided with the period some 3.8 billion years ago, when life is believed to have begun on Earth, Grotzinger said it appeared to be in the same range.
Mars is cold, dry, and hostile now, and the likelihood of life existing on its surface is considered vanishingly slim. But with its portable chemistry and mineral labs—the first ever to be used on Mars—the rover team is now finding the long-expected evidence of a once warmer and wetter Mars. This was made possible by use of the drill, also a first for a rover on Mars.
But in addition to upcoming delays as a result of the conjunction, Curiosity hasn't been able to conduct any science experiments for almost two weeks due to an "anomaly" in the rover's main onboard computer that caused a shutdown and a switch to a backup computer.
Curiosity troubleshooters have suggested that the computer malfunction may have been the result of a cosmic ray strike. It is because of this delay that the second hole won't be drilled at Yellowknife Bay until May.
NASA's latest Mars rover landed in Gale Crater in August and was expected to head fairly quickly to the huge mountain at the center of the crater, Mount Sharp. But a detour to the Yellowknife Bay region has been so productive that it remains unclear when Curiosity will continue its trek to the mountain.
its just rather trivial at the moment. its proving something that was already etched into our brains as 'knowledge'...hopefully they do make it to the mountains before the rover expires. I don't know which will be worse, finding there was never life there meaning we are a little me more alone in the universe maybe (so then emphasising the point that we better look after earth because theres nowhere to run too), or that there was life which would make us even more insignificant in the wider picture...both once society embraces what they both mean will be testing times if they aren't already
We're not from Mars, that's bat s*** crazy. Say what you want about me but I'm not sitting with a tin foil hat on, totally delusional and with no comprehension science.
mars was once earth...they find a planet were life is possible and then they find earth...our intelligent designers are martians :D....
How about rather than (or in addition to) trying to find evidence that life once existed on Mars, we attempt to establish life right now on the moon.
@Ken Truitt Sorry Ken, but if you knew the science behind that and the evidence from the Earth Dome projects, you would know why that can't happen.
The news is inspiring but and we may learn things that will have broad applications. But the moon and Mars are probably equally unsupporting of living things presently. It's just that the moon is a lot closer. SO, let's learn about living off Earth by colonizing the moon.
I think it is a great idea. Everyone knows that Earth is becoming more polluted by the day. In a couple million years(or less) this planet will be a trash heap. If Mars is habitable then our descendants will have a place to go so they won't end up like the people in Wall-E.
@John Berube I respectfully disagree, John. Anyone who has read Asimov's Foundation series should recognize that Earth will very possibly become like Trantor! "Trash heap"? Perhaps. But definitely like Trantor. If you haven't read Foundation, my apologies, but for those who have, I believe Asimov's world of Trantor is one possible example of "celebrating diversity" gone awry when the real solution to humankind getting along is to celebrate humanity, what we have in common, and what we are capable of when we work together, regardless of our superficial qualities. Apologies to fans of Wall-E, I have not seen the movie. Should I regret it? Or is it just another Hollywood attempt at PC indoctrination?
@John Berubeand then we give it another few thousand years on a new planet before we completely strip it of its resources and pollute it until we'd have to find a new planet to live on. it is an interesting idea and it could very well happen someday in the future, but it allows justification to continue exploitation, pollution and the never-ending desire for economic growth. if it becomes as simple as moving to another planet once we've trashed the one we're living on, we will forget the value of a planet and its beauty for what it is. it will become simply about resources. why not just avoid the problem while it's still a possibility? (that is, before our planet becomes a "trash heap")
@haley l @John Berube You are missing key elements in your theory , like single asteroids that have more rare(heavy) elements in their composition than all the rare elements we've mined since the dawn of the indurstial revolution.If it's light rare elements you're looking for then you should know we have 4 gas giants in our solar system ... stripping a planet of resources is no longer necessary , and you should view the current day usage of fossil fuels and the rest as a necessary step to accheve access to space and better technology(which will eventually remove the need for polluting agents) .
@John Berube This is proof that Mars *was* habitable. It is quite beyond that now, and with the frequency of larger meteorite impacts, it wouldn't be a good candidate for the teraforming dreams we all have.
This is crazy. How much money will continue to be wasted worrying about foolish things like inhabiting another planet rather than finding a fix for ours. We truly are living in a Godless World when we step over poor and sick to spend money satisfying the desire to become all knowing.
@Tim Gilbert No, Tim. Adam and Eve wanted to become "all knowing". The Babylonians wanted to become "all knowing". Present day civilization........not so much.
Current NASA Budget: $17 Billion
Current Military Budget: $1.4 Trillion
I think you should re-evaluate that statement.
Are "they" finally leading up to disclosures about "intelligent life," perhaps even our own ancestors, having lived there, as evidenced by Cydonia and other sites, and then, after ruining that planet, coming here ?
As mr Grotzinger stated , the period of this habitability is in the same range with life starting on earth , 3.8Gya . Considering the solar system was formed 4.5Gya i find it hard to belive 0.7Gya is enough to evolve an advanced civilisation capable of self-destruction.
Maybe their science evolved faster because they didnt had religion and the inquisition.
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