A new analysis of the largest known deposit of carbonate minerals on Mars suggests that the original Martian atmosphere may have already lost most of its carbon dioxide by the era of valley network formation.
"The biggest carbonate deposit on Mars has, at most, twice as much carbon in it as the current Mars atmosphere," said Bethany Ehlmann of the California Institute of Technology and NASA Jet Propulsion Laboratory, both in Pasadena. "Even if you combined all known carbon reservoirs together, it is still nowhere near enough to sequester the thick atmosphere that has been proposed for the time when there were rivers flowing on the Martian surface."
Carbon dioxide makes up most of the Martian atmosphere. That gas can be pulled out of the air and sequestered or pulled into the ground by chemical reactions with rocks to form carbonate minerals. Years before the series of successful Mars missions, many scientists expected to find large Martian deposits of carbonates holding much of the carbon from the planet's original atmosphere. Instead, these missions have found low concentrations of carbonate distributed widely, and only a few concentrated deposits. By far the largest known carbonate-rich deposit on Mars covers an area at least the size of Delaware, and maybe as large as Arizona, in a region called Nili Fossae.
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But if the atmosphere was once thicker, what happened to it? One possible explanation is that Mars did have a much denser atmosphere during its flowing-rivers period, and then lost most of it to outer space from the top of the atmosphere, rather than by sequestration in minerals.
If Mars were losing its atmosphere to outer space, wouldn't we able to detect a trail of gas from the planet?
(Score: 3, Interesting) by mhajicek on Saturday September 05 2015, @04:35AM
From what I recall reading, Mars lacks a strong magnetic field to divert the ionized solar wind. This means the upper atmosphere can get literally blown away. It probably would have been measurable back when it was thick, but there isn't much left to get blown off now.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 2, Informative) by Anonymous Coward on Saturday September 05 2015, @04:37AM
Americans don't know about US geography, and foreigners don't care about US geography. Comparing area to US states is a pointless waste of time either way.
(Score: 1, Flamebait) by mhajicek on Saturday September 05 2015, @04:41AM
So is complaining about a submission.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: -1, Troll) by Anonymous Coward on Saturday September 05 2015, @04:46AM
Complaining about a complaint is doubly dumb.
(Score: 2, Funny) by Anonymous Coward on Saturday September 05 2015, @04:55AM
2Complaint about a complaint
(Score: 0) by Anonymous Coward on Saturday September 05 2015, @05:34AM
"If Mars were losing its atmosphere to outer space, wouldn't we able to detect a trail of gas from the planet?"
Yes, though the size of that trail depends on how thick the atmosphere is. There's also a trail from the Earth losing it's atmosphere, slowly.
(Score: 4, Funny) by aristarchus on Saturday September 05 2015, @06:10AM
So, now we have proof that anthropogenic global warming is not what happened to Mars. And by some rather strange analogy with no basis in reality, that means AGW is not real on Earth. Yeah,. . . I would buy stock in that. But only if that guy attached to the other guy in the Swartzennegger version of Total recall says so. What was his name? Led the resistance? Ah, Kuato! There is the source for all the Republican deniers! At least those you are not in jail for imposing their view of the law instead of, you know, the actual law. F**king Martians. Especially those in Kentucky.
(Score: 1) by khallow on Saturday September 05 2015, @08:05AM
And by some rather strange analogy with no basis in reality, that means AGW is not real on Earth.
What's the point of grotesquely misrepresenting someone's argument? As I recall, the actual argument was that contemporary warming on Mars to that of Earth indicates that solar output has been underestimated.
(Score: 0) by Anonymous Coward on Saturday September 05 2015, @01:02PM
Another stupid Global Warming Warrior.
(Score: 2) by hendrikboom on Saturday September 05 2015, @02:21PM
There cannot be anthropogenic warming without anthropos. Maybe in few years when we're there it can start, but not yet.
(Score: 2) by aristarchus on Monday September 07 2015, @06:44AM
Um, we have many billions already? What do you think "anthropos" are? "Homos" in another language. Souix in another. Or just "the blackheads" in Chinese. Yes, well over the limit, if they continue to burn fossil fuels, not to mention the methane emissions! Cut it out with the beans, alright already?
(Score: 2) by hendrikboom on Wednesday September 09 2015, @12:20PM
True, but none of them are on Mars yet.
(Score: 2) by Gravis on Saturday September 05 2015, @06:35AM
so which theory was eliminated? seriously, i read this and all it seems to do is list another way that mars may have come to it's current state.
so again, serious question, which theory does this eliminate?
(Score: 0) by Anonymous Coward on Saturday September 05 2015, @09:27AM
Well if Mars had rivers and liquid water they probably expected it to have a thicker atmosphere since water with no atmosphere (or a much thinner atmosphere) tends to turn to ice at low pressures. But I guess this suggests that it didn't have a thick atmosphere which begs the question how did it supposedly have liquid water in the past.
(Score: 2) by aristarchus on Saturday September 05 2015, @08:14PM
which begs the question how
Once more into the breach! No, no it does not beg the question. It might beg for -a- question, if it was capable of begging. "Question begging" is circular reasoning. Using the phrase as you do here makes you look like something of a "damp squid".
http://begthequestion.info/ [begthequestion.info]
https://en.wikipedia.org/wiki/Begging_the_question [wikipedia.org]
http://www.jeremybutterfield.com/damp-squid.html [jeremybutterfield.com]
(Score: 0) by Anonymous Coward on Sunday September 06 2015, @12:38AM
It's a figure of speech.
Gosh, really ... pedantic much.
(Score: 2) by aristarchus on Sunday September 06 2015, @12:58AM
It's a figure of speech.
Gosh, reading comprehension much? No, it is not, it is a mistake for a figure of speech brought on by people who have heard more than they have read, and create "eggcorns", things that seem to make sense because they mistake what is being said. So this is basic sophmorism: a mistake that only someone with enough education to be dangerous could make.
There is a whole database of them, here: http://eggcorns.lascribe.net/ [lascribe.net] . Some people there are "getting a new leash on life". Others are "for all intensive purposes" such that they "lack toast and tolerant". And then there are those who have special day when they can have "holland day sauce". Actually, these mistakes are really quite amusing. I recommend the episode of "The IT Crowd" that involves "pedal stools" and the aforementioned "damp squid".
Sorry that you find trying to save people from continuing to look like semi-literate ignoramouses pendantic. It hangs heavy on me and my meeses.
(Score: 0) by Anonymous Coward on Sunday September 06 2015, @07:52PM
Point taken, I will try to be more careful next time.
(Score: 2) by M. Baranczak on Sunday September 06 2015, @02:23AM
It's a figure of speech.
Yes, it is. And you don't know how to use it. Worse than that, you seem to have no intention of learning how to use it correctly.
(Score: 2) by aristarchus on Sunday September 06 2015, @07:40AM
Yes, it is. And you don't know how to use it.
Um, sorry to bring this up, but just saying something like this does not remotely approach proving that it is so. In fact, if you were not so obviously frightened by my ponderous pedantry, you could just research the proper usage yourself and see that "No, it isn't!" and "Yes I do." We greeks more or less invented logic, you know. Further, since you appear to be as intelligent as the average Anthropogenic Global Warming denying Gamergater, in not all cases does common use succeed in changing language and establish correct usage. It can, as in the case of eggcorns (which is a mistaken substitution for "acorn"; yes, I knew you did not bother to look it up), destroy a language with meaningless pretended erudition. I much prefer honest slang.
And, it seems you have no intention of learning what the figure of speech actually means! It must have been you that George W Bush had in mind when he asked, "Is our children learning to put food on their families?"
(Score: 2) by M. Baranczak on Sunday September 06 2015, @04:11PM
(Score: 2) by aristarchus on Monday September 07 2015, @06:04AM
"Oh, but this is Abuse! So sorry! You want room 12a, next door." (For those who do not get the reference, Monty Python, "The Argument Clinic") But seriously, sorry! Of course, since you were responding to me, I thought you must be a troglodyte attempting to force the incorrect meaning of "begs the question". Which did seem implausible, which was also why I kind of went off the deep end, the deep end of pedantry. (Wow, how far down does it go? Should we drop a philosopher? Ow, wait, a grammarian!). But seeing how you agreed with me when you could understand me, we are all well. Even the original transgressor has (or at least an AC bearing similar garb) admitted to the initial error and promised good behavior in the future, I think we can chalk the entire exchange up as a net gain. The atmosphere of Mars is still something of a mystery, and deniers gonna deny, but life goes on and language will persevere, with the efforts of Social Justice Grammarians! Ho! Hoe! Whore! See, it happens, if we do not pay attention.
(Score: 2) by wonkey_monkey on Saturday September 05 2015, @11:26AM
Sequestration of CO2, I think.
Years before the series of successful Mars missions, many scientists expected to find large Martian deposits of carbonates holding much of the carbon from the planet's original atmosphere. Instead, these missions have found low concentrations of carbonate distributed widely, and only a few concentrated deposits.
systemd is Roko's Basilisk
(Score: 3, Informative) by Covalent on Saturday September 05 2015, @10:47AM
Then this is your big chance to get away from it all.
OK, odd trek references aside, those molecules had to go somewhere. As I see it, there are only three possibilities:
1. The carbon dioxide went into the rocks as carbonate - the article suggests this is very unlikely as the rocks don't have enough carbonate.
2. The carbon dioxide leaked into space - more plausible, particularly without a magnetic field (see above)
3. There wasn't much carbon dioxide to begin with - unlikely as the stuff is pretty ubiquitous, including making up most of Mars' atmosphere now.
The tricky bit is that the surface seems to have once been covered with water to some extent, which means it was once a warm and high pressure place. My guess is that Mars lost its volcanism quickly, which lead to little carbon dioxide being added to the air. So Mars was warm and wet, but only briefly. The remaining gas was absorbed into the rocks (a little) and lost into space (most). If there wasn't much to begin with, it could reach equilibrium ages before we came to measure it.
You can't rationally argue somebody out of a position they didn't rationally get into.
(Score: 2) by Phoenix666 on Sunday September 06 2015, @03:39AM
If the carbon dioxide leaks into space, where does it go from there? Does it cease to exist, or does it get swept up by the planets farther out in the solar system? Is it that it's still there, presumably, but dispersed below the sensitivity of our instruments to detect it?
When they talk about atmosphere "leaking into space" it sounds like they're talking about the atmosphere is being destroyed rather than being re-distributed in the ecliptic, as it must if Conservation of Matter is true. And if the atmosphere is being lost to the ecliptic, then wouldn't that same planetary body start sweeping some of that same atmosphere up again as it comes around for another pass?
Washington DC delenda est.
(Score: 0, Troll) by Anonymous Coward on Saturday September 05 2015, @01:24PM
Is phoenix gewg's stupid niece?