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Mars Rover Finds Complex Chemicals But No Organic Compounds
techtech writes in with the results from the first soil samples tested by the Curiosity rover. "Although NASA's Curiosity rover hasn't yet confirmed the detection of organic compounds on Mars, it's already seeing that the Red Planet's soil contains complex chemicals — including signs of an intriguing compound called perchlorate. The first soil sample analysis from Curiosity's Sample Analysis at Mars lab, or SAM, was the leadoff topic today at the American Geophysical Union's fall meeting in San Francisco. The findings were eagerly awaited because of rumors that the Curiosity team was on the verge of announcing major findings — and although NASA tamped down expectations, the scientists said they were overjoyed with the first round of analysis."
on Curiosity and are just about ready to go... http://imgur.com/VWcAU
:o)
NASA can't keep up being the "boy who cried wolf." People will just stop listening if every little thing is "breakthrough" and something "earth-shattering!" My goodness.
Nothing is more dangerous than a programmer with a screwdriver.
What a let down.
Seems like they wanted to try to build some excitement when there was nothing to be excited about.
Reminds me of this recent SMBC comic.
There is some good science being done and the Good Stuff will be when Curiosity reaches the clay layers at the base of Mt Sharp, so be patient. There is also the minor mystery of the chlorinated methane products...
There they will find the Rocknest Monster and the end of the rover. (Warning: not funny unless you actually read TFA.)
Or aliens?
on Curiosity and are just about ready to go... http://imgur.com/VWcAU :o)
That doesn't look like Jimmy Hoffa to me...
Understanding the scope of the problem is the first step on the path to true panic.
They mention that the Calcium Perchlorate may be an energy source. How about using it to manufacture rocket fuel on mars? It's similar to other oxidizers used in solid fuel rockets. Wouldn't it be strange if the fuel for a return-to-earth trip could be manufactured right there from materials lying right there on the planet surface? Or am I totally smoking something?
Probably had some flunkies hide all the plastics and mess up some sand. I'm also willing to bet that those brave volunteers willingly had their gelsacs pierced to preserve the secret.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
I only got a 3 on the AP Chemistry test many years ago, but even I know that perchlorate is not "an intriguing compound", but an ion that forms a variety of salts.
I can't believe Grotzinger would be so sloppy with his terminology when discussing sifting Martian soil samples into the SAM.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Perchlorate is intriguing for a number of reasons that are tangental to the compound's intrinsic character.
First, it is a potentially biologically useful compound as an oxygen source for single cellular respiration in autochemotrophs.
Second, if concentrations are high enough, the salt lowers the melting point of water sufficiently that martian soil could be "moist" at sufficient depths.
Also, the compound usually only forms in nature from UV irridation of aqueous saline solutions. A high abundance of the mineral is very suggestive of a very different mars from what we see now.
Previous rovers have detected gypsum, and perchlorates at other locations. Additional samplings of perchlorates increases the probability that the mineral is very prevelent in the crust, which greatly increases the chances of finding microbiotic life.
The fact that perchlorate salts are about as "interesting" as O2, salt, silicon dioxide, and other inorganic substances here on earth does not mean that they are uninteresting in an environment that is radically different from our own.
I am only an expert on this because it contaminated all our drinking water around Las Vegas valley. It is a very important component in rocket fuel as I recall (like makes it go bang).
So, yea, I can see that being kind of important if you ever want to go home from mars.
Isn't perchlorate a component of some fuels? Perhaps it comes from the hover stage during the lowering phase....
I thought the discovery of perchlorates dashed their hopes of finding microbial life - something about it being a wicked oxidizer?
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
A third rate hack who pimps his blogs... that's all Phil Plait is.
Well, as a regular reader, I'd say he's more "A first-rate hack who pimps his informative, entertaining (though over-focussed on AGW zealotry) blogs."
If you don't learn anything from his blog, and aren't simply blown away by the galactic imagery he links to, then you're simply dead inside.
http://www.slate.com/blogs/bad_astronomy.html
And the worms ate into his brain.
I bet Martian wolves would have to be pretty bad-ass, surviving on rocks and stuff, given the dearth of children to carry off on Mars.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
It is a wicked oxydizer, and it does kill most terrestrial microbes almost instantly. (Its basically bleach.)
However, the degree of lethality is deprendent on concentration of the perchlorate salt (my understanding was that it was under 1% of the sample, suggesting it was a low yeild, but omnipresent mineral), as a small qualtity would be tolerable to extremophiles, which is what you would expect in the extreme conditions on mars.
Life on mars appears more and more to fall into a very narrow band of habitablility, like the photosynthetic soil microbes of antarctica, assuming it exists at all.
Missions like this one give us a better understanding of martian environmental conditions, and allow us to make better guesses about what areas of mars might potentially harbor life.
I'm surprised nobody else has pointed out yet, the headline for the first-linked article says "Curiosity rover finds organic compounds...", directly refuting the statement in the first sentence of the article: "Curiosity rover hasn't yet confirmed the detection of organic compounds on Mars"... geez, what a flub. Who's editing at cosmiclog.nbcnews.com?
...but isn't perchlorate an ion? The article reads:
including signs of an intriguing compound called perchlorate
Did they detect perchlorate ions? Or perchlorate compounds? Or perchlorates perhaps? I'm sorry, but this just struck me as a rather in-your-face mistake if that is indeed how it was reported. Or maybe I'm just being pedantic and should find a better use of my time?
Don't worry, the guy that let the "earth shattering" leak get out had been dealt with. Which in government speak means that he was promoted, given a big fat raise, and now sits alone in an office all day and fears losing his income if he ever tells the truth about this. The perchlorate story is the story that people can handle, just as Roswell's weather balloons were last century. Nothing to see here, move on.
I'm an American. I love this country and the freedoms that we used to have.
Oxygen is, wait for it, a wicked oxidizer. Current life forms have evolved multiple processes to mitigate damage caused by having such a reactive chemical in the atmosphere.
But it's an energy source. Gotta have those electrons.
Faster! Faster! Faster would be better!
chemistry fail AC.
Try again after you learn the differences between compounds, molecular elemental quantities, mixtures, solutions, and coloids.
The perchlorate ion is a covalently bound molecule of oxygen, chlorine, and hydrogen. It is therefor a compound. It forms ionic associations with metals, and decomposes organic compounds via oxidation reactions.
*raspberry*
Well it sure prevents entire classes of organisms to develop there, but life might be based on different reactions and elements. As long as it grows, multiplies, and adapts itself to a changing environment it can be classified as life (according to genesis chapter 9, I mean :D)
Earthicans banned it in 2010...
http://www.nyc.gov/html/dep/html/air/dry_cleaners_perchlorate.shtml
Mission: To provide products that consume time and energy as entertainingly as permitted by the laws of thermodynamics.
Entry: "chemical compound"
Entry: "chemical compound"
Entry:"chemical compound"
What definition of "chemical compound" are you using exactly, that perchlorate ion would not be a chemical compound?
As for the question: calcium perchlorate.
http://www.youtube.com/watch?v=3JpwjnMFlJI
by TheSpoom (715771) Uncaring Linux user here. I have nothing to add to this but please continue. *munches popcorn*
Oh, as for it not being a mineral, you fail again. It is not produced by an organic process, does not contain carbon, and forms natural crystalline associations in soils. Perchlorates are minerals.
Eg, did you know that rock salt is a mineral? Geologists call it "halite". ;) perchlorate complexes are indeed minerals my friend.
Because he's got better things to do than argue with ACs on Slashdot? Really? The guy has kids. I wouldn't bother arguing with ACs on Slashdot either if I had kids to troll.
Is this is the earthshaking news we were promised, or are we still waiting for that? Okey, so the first full soil sample analysis was completed. Did they expect it to fail halfway through or something?
"Be nice, veer left, and never stop thinking" Iain Banks - Walking On Glass
OMG RUN, CURIOSITY! IT'S ONE GIANT BOMB!!!!! Seriously, isn't perchlorate a significant component of some high explosives?
That isn't how the language works.
A compound is an identically structured association of different types of atoms, participating in either covalent or ionic bonding, resulting in a substance that is fundamentally different from its constituent parts. Eg, mixing nitrogen and hydrogen gasses together in a tank will not be the same as a tank containing the same stoichiometric quantity of anhydrous ammonia.
In fact, ionized anhydrous ammonia is a perfect test subject for this debate.
Ionizing ammonia by ripping off a hydrogen atom causes it to become free amonium ion, a polyatomic ion, which you are asserting is not a compound. Under laboratory conditions, and in interstellar clouds, this substance does exist in free and unbound states. The mere fact that the molecule has a reasonably strong ionic charge, and a strong affinity for electron accepting metals and hydrogen (protium) atoms does not remove it from being in the "compound" class of substances. Ammonium ion behaves very differently from a mixture of ionized nitrogen and hydrogen gasses of similar charge.
Symantically, "compound" is a classification that is intended to differentiate between "mixtures", "solutions", and "colloids", and polyatomic molecules.
Components in a mixture retain their individual chemical identities, and can be seperated based on that retention of chemical identity.
A solution is one compound being dissolved into another. When the solvent is removed, the solute will reconstitute unchanged, but disperses eavenly within the solvent when mixed.
A colloid is a mixture of suspended microparticle of one substance, floating in a homeostatic suspension inside another substance.
A polyatomic molecule is comprised of homogenous atoms held together by covalent or ionic potentials. (Eg, N2, H2, O2, etc.)
A "polyatomic ion" can be a compound, but also not be a compound.
For instance, ozone (O3-) is a polyatomic ion that is NOT a compound. (It also tends to decompose rather than engage in an ionic bond, but in its free state, it is an electrically charged polyatomic molecule that is not a compound.)
NH3 is a polyatomic ion that *is* a compound, because it is comprised of discrete and identical quantities of heterogenous atoms. (All ammonium ions are the same: NH3.)
In this case, perchlorate is comprised of 4 oxygen atoms, 1 chlorine atom, and one hydrogen atom. It is therefor a polyatomic ion, that is also a compound.
Compound and polyatomic ion are not exclusive.
That is where the disconnect lies.
Returning to interstellar ammonium, the usual way to describe this is to call it ionized ammonia. This is to differentiate it at the macro level from ammonium ions suspended in water, or interacting with some other partner or solvent. This is simply to avoid confusion. Likewise, to describe perchlorate all by itself, one would likely refer to it as "anhydrous, ionized perchloric acid." (Given the strength of the ion, and the thermal instability of the ion, it is unlikely that this could form without radically unusual conditions though.)
The point here is that the burden to show that perchlorate is NOT a compound rests on your shoulders, and not the burden to show that perchlorate IS a compound on mine.
I have pointed to the established definition of what a compound is, which fully encompases all aspects of the perchloate ion. You now have to assert why the ion is not a compound.
Yup, I also remembered that one. Even worse, the Viking probes likely also found the same schtuff, circa 1975.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Your argument is immaterial. Chemists don't call it that, because polyatomic ion is more precise, and not all polyatomic ions are compounds.
The terms are not interchangable, but many are a subset of the other.
If we play a substitution game to test the logic, it makes sense.
You say: "perchlorate ion is not a compound. It is a polyatomic ion."
I respond with this substtution:
"A rabbit is not an animal. It is a mammal."
There are animals that are not mammals, but a rabbit is both an animal, and a mammal.
In the same way, perchlorate is both a polyatomic ion, and a compound.
Scientists use precise language, whenever possible. The amusing diversion that they don't use the general descriptor when dealing with a specific type of molecule does not add weight to your argument.
I will say again. The burden of proof is yours, to prove that it ISN'T a compound.
I'll be waiting.
Blagh.. you are right!
That will teach me not to rant on the internet while doing NC programming!
Still, despite the naming faux pas, the argument still holds.
However, one probe's sampling is insufficient to build a general soil minerology statistic from.
Imagine, aliens send a probe to a mountain on earth and discover gold nuggets. Would it be sensible for the aliens to conclude that the earth has a high soil concentration of gold? Clearly not.
Likewise, nasa scientists thought the perchlorate discovery was a very unusual anomaly.
Discovering yet more perchlorate several hundred kilometers away in a different region makes the case that the perchlorates could be a widespread feature in the surface regolith.