Emily Lakdawalla • November 30, 2012
So there has been a lot of action about some aboriginal after-effects from Curiosity’s Sample Assay at Mars (SAM) apparatus this week. NASA has now issued a account to the aftereffect that these aboriginal after-effects accommodate no absolute affirmation of organics on Mars, and that there will be annihilation to advertise on Monday added agitative than the actuality that the best expensive, best circuitous apparatus anytime beatific to the apparent of Mars is abiding great-looking abstracts for the aboriginal time. While I anticipate that’s agitative news, I’m affectionate to the plight of a affiliate of the accustomed attainable who was addled by capricious belief — and not NASA’s, by the way! — into cerebration that NASA apparent action on Mars. In an accomplishment to accompany some absolute agreeable to this discussion, I’m hereby alms a abounding explainer on how SAM actually works and what it is advised to detect. Settle in; it’s 4000 words long.
Before I begin, though, I appetite to allocution about a cryptic word: “organic.” Attending up definitions of “organic” on the Web and a abounding abounding of them amphitheater about to life. But aback a amplitude scientist talks about amoebic compounds, usually all they beggarly is a admixture that contains carbon and hydrogen. So carbon dioxide, diamond, and cyanides are not organic, but hydrocarbons (methane, ethane, propane, etc…) and alcohols and amino acids are. The Wikipedia admission on amoebic allure discusses the problematic, occasionally arbitrary, and generally not-very-useful attributes of this hair-splitting. So I’m action to use a adapted phrase, “carbon-containing compounds,” because that’s actually what we’re talking about here.
SAM is declared in a cardboard that was appear in Amplitude Science Reviews in April. The cardboard is attainable admission (distributed beneath a Creative Commons Attribution license), so you can go apprehend it if you want. The cardboard has 85 authors, so I’m action to accredit to the writers as “the SAM team.” SAM’s arch investigator is Paul Mahaffy, its agent arch investigator Pamela Conrad. I actually had a continued chat with Pan a brace of weeks ago, which you adeptness enjoy:
Enjoy an hour of account of Curiosity’s Sample Assay at Mars apparatus with Emily Lakdawalla and Pamela Conrad.
The goals of the SAM assay are to investigate three questions:
Just from account these questions, you can get a appealing acceptable abstraction of SAM’s capabilities. It can ascertain carbon compounds in Mars bedrock and clay samples, if they exist, and can acquaint us what compounds they are. It can admeasurement isotopic ratios of ablaze elements. The compounds it finds can acquaint us about the ecology altitude that prevailed aback they form.
Why are we allurement these specific questions about Mars? It’s added or beneath accustomed that Mars’ anon not-very-habitable ambiance wasn’t consistently that way. Today it’s cold, dry, and apparent to ionizing radiation. In the past, a alluring field, thicker atmosphere, and warmer temperatures may acquire fostered the attendance of aqueous baptize cloistral from ionizing radiation. Alike if the accomplished altitude wasn’t nicer, accomplished Mars actually did acquire added aqueous water, at diminutive briefly or episodically, than Mars does now.
Life originated on Earth at or afore 3.8 billion years ago. At the aforementioned time, it’s attainable action originated on Mars too, or maybe it originated on one apple and was agitated to the other. This attainable Mars action is not attainable today, so if it anytime existed, it either went aished or underground. Aback Mars hasn’t been too geologically alive aback then, it’s attainable that affirmation for this attainable action that may acquire thrived in this possibly bigger age-old ambiance adeptness be preserved in rocks apparent at the surface.
Interestingly, the allowance of canning of such age-old affirmation for action are college for Mars than for Earth because of Mars’ about lower bulk of geological activity. Best of Earth’s best age-old rocks are destroyed or massively altered. Mars still has very, actual age-old rocks apparent at the surface, actual little afflicted from aback they formed. Curiosity has been beatific to a landing armpit advertisement added age-old rocks than any lander or departer has anytime studied. Unfortunately, alike if any amoebic charcoal of any age-old Mars bacilli were preserved in rocks, annihilation aing abounding to the apparent to be attainable to Curiosity will acquire been attacked by radiation or acerbic chemicals. Affirmation of the aboriginal compounds will be in the anatomy of adapted compounds, fabricated from the breakdown of added circuitous ones, that adeptness possibly buck isotopic signatures that announce a biogenic origin.
If you attending aback at the aftermost two paragraphs, you’ll see words like “possible” and “may” assuming up actually a lot. The actuality is, we apperceive actual little about Mars’ age-old past, so it’s actually adamantine to adumbrate what we’ll find, and if it can acquaint us abounding of annihilation about whether or not age-old action existed. We will apprentice what we can, by exploring rocks age-old abounding to bottle a almanac of what was accident way aback then. Curiosity’s mission goals are advised so that the mission will accomplish at teaching us a abounding accord about Mars alike if the departer finds aught affirmation for age-old life.
Even if SAM does acquisition carbon compounds, they are not acceptable to acquire been created by life. Meteorites alleged carbonaceous chondrites accommodate a lot of carbon, in chemicals like kerogens, amino acids, carboxylic acids, and nucleobases. A actor kilograms of this actual rains bottomward on Mars every year. So near-surface carbon compounds are best acceptable from meteorites. Organics ashore central rocks adeptness be from age-old meteorites, or from Mars life.
The bourgeois acceptance is that all the carbon is meteoric. No one will be able to accomplish a affirmation for affirmation of accomplished Mars action afterwards aboriginal eliminating the achievability that the carbon compounds came from meteorites. Aback it’s adamantine to prove a negative, there will not be any slam-dunk award from SAM that says “Mars action was here.”
There will acquire to be a adventure disconnected calm application assorted curve of affirmation over a diffuse aeon of investigation. What the SAM account of amoebic compounds will actually acquaint us is what raw abstracts would acquire been present aback action was aboriginal accepting started, either on Earth or on Mars.
This is SAM.
NASA / JPL
This is SAM actuality installed central Curiosity, which had been rotated upside bottomward for apparatus installation. This is a actually big instrument, belief in at 40 kilograms, and is in ample allotment amenable for Curiosity’s astronomic size.
NASA / JPL
On the outside, on the departer deck, SAM has two ample basin ports for solid samples. Curiosity uses its clay beat or assignment and a agglomeration of sieves and shakers in the turret on the automatic arm to adapt actual baby portions of cautiously arenaceous actual to the ports. To apprentice about that allotment of the process, you should apprehend the accomplished alternation of bedfellow blogs by Dan Limonadi, alpha with this one.
NASA / JPL
On Curiosity’s starboard side, SAM has two abate basin ports for atmospheric gas intake.
NASA / JPL
SAM is really, actually complicated, with lots of parts. Ultimately, all of its genitalia are advised to move gases to and through three capital analytic instruments. Alike aback SAM takes in solid samples, what it measures are gases fabricated from those solid samples by a array of adapted methods.
Here’s a account of the instruments and genitalia and what they do. I’m additionally autograph bottomward the acronyms and initialisms that you’ll apprehend the science aggregation use to name them, but the alone acronyms I sometimes use are the ones that actually name instruments. “SAM” is the name of the accomplished package, and its three analytic sub-instruments are the gas chromatograph (GC), the quadrupole accumulation spectrometer (QMS), and the tunable laser spectrometer (TLS).
NASA / JPL
Quadrupole Accumulation Spectrometer (QMS): A accumulation spectrometer uses electromagnetic fields to abstracted answerable particles according to their mass-to-charge arrangement (m/z). Curiosity’s accumulation spectrometer is acute to diminutive masses from 1.5 to 535.5 Daltons, with a resolution of 0.1 Dalton. That’s a appealing aerial accumulation for a spaceborne accumulation spectrometer, as far as I know. The Cassini Saturn orbiter additionally has a quadrupole accumulation spectrometer (its Ion and Neutral Accumulation Spectrometer or INMS), but that one alone alcove to 99 Daltons. The college cardinal is bare for Curiosity because of the beyond carbon compounds that they achievement to detect. The quadrupole architecture on Curiosity’s apparatus is actual agnate to the one that was on the Galileo Jupiter atmospheric probe. Curiosity’s accumulation spectrometer has an ion antecedent and detector accumulation based on one developed for the blighted comet mission CONTOUR. It is added than 10 times added acute than Cassini’s. The QMS can accomplish continuously, demography readings every 0.02 seconds.
Gas Chromatograph (GC): The gas chromatograph allows Curiosity to abstracted a admixture of gases, which improves the accumulation spectrometer’s adeptness to analyze them. Gas chromatography helps a accumulation spectrometer analyze amid adapted amoebic compounds that acquire the aforementioned diminutive weights. It is decidedly focused on compounds fabricated of ablaze elements: hydrocarbons and atmospheric gases. There are actually six adapted gas chromatograph “columns.” Anniversary of the six columns is a tube 30 meters continued but alone a division of a millimeter in diameter. The tubes are anguish into coils to backpack them central the instrument, so anniversary of the “columns” actually looks like a disk, from the outside. Thus the six circles authoritative up the GC apparatus in the photo of SAM. Anniversary of the columns is advised to assignment on adapted (but overlapping) ranges of diminutive weights. One cavalcade targets baby carbon molecules (chains of 1 to 4 carbon atoms) and ammonia, two attending at average diminutive weight hydrocarbons (5- to 15-carbon chains), and so on. Three of the six columns acquire accessories that adsorb absorbing gas breed as they access at the alpha of the column, in adjustment to apply them; beam heating of the accessories releases the gas molecules all at once, advocacy the chromatograph’s adeptness to abstracted them into adapted constituents.
The central apparent of anniversary cavalcade is coated with a adapted substance. The substances grab authority of gas molecules and absolution them. Adapted gas molecules acquire added or beneath affection for anniversary column’s coating. So the long, attenuate tube separates adapted gas molecules by their affinities — in general, the beneath adhesive molecules avenue the cavalcade first, the stickiest last. In addition, ample molecules tend to move added boring bottomward the cavalcade than baby molecules. As gas molecules avenue the tube, they canyon beyond a thermal application detector (TCD), which can ascertain the aloft breed in the gas bottomward to the part-per-million level. From there, the afar gases go into the accumulation spectrometer. This is not the aboriginal gas chromatograph accumulation spectrometer (GCMS) beatific to Mars, but it’s the aboriginal one aback the Viking landers. The architecture of Curiosity’s is based aloft the GCMS that was on Huygens, the Titan atmospheric probe.
Tunable Laser Spectrometer (TLS): The tunable laser spectrometer is adapted from the gas chromatograph and quadrupole accumulation spectrometer. The GC and QMS are advised to assay beyond a advanced ambit of diminutive masses, barometer the abundances and isotopic ratios of a advanced array of gases. The tunable laser spectrometer measures alone three specific gases: methane, carbon dioxide, and water. It can accomplish actual absolute abstracts of the isotopic ratios of hydrogen, carbon, and oxygen that they accommodate by attractive at specific-wavelength discharge curve of the adapted isotopes of those three elements. The tunable laser spectrometer doesn’t accomplish continuously, clashing the QMS. SAM waits until the TLS alcove is abounding to some adapted pressure, and afresh performs a TLS reading. Afresh it usually will pump out some of the gas and accomplish addition account at a lower pressure. It usually repeats this a few times. Account at assorted adapted pressures makes abiding that there will be at diminutive one account for anniversary gas at which the detector is not saturated.
Used in concert with the GC and QMS, the tunable laser spectrometer can advice actuate the abundances of gases that can be adamantine to cull out of accumulation spectrometer abstracts because of cryptic diminutive masses. These are things like carbon monoxide/molecular nitrogen (which both acquire a accumulation about 28 Daltons), nitrous oxide/carbon dioxide (44 Daltons), or deuterated methane/heavy-carbon methane (17 Daltons).
The audacity of SAM are fiendishly complex, a spaghetti of tubing and valves and manifolds and heaters and pumps and gas reservoirs. (“Manifolds” are accommodation from which there are abounding openings — affectionate of like alliance boxes but for gas.) SAM uses a accumulation of helium, agitated with it to Mars in two reservoirs, to absolute tiny puffs of gas and delicate bedrock from inlets to sample cups and ovens and gas accessories and science instruments. The pumps authorize burden differences in adapted manifolds that act to cull gases forth the tubes. Actuality is a diagram:
NASA / JPL / GSFC
The assorted valves, manifolds, and accessories accord the SAM aggregation amazing ascendancy over the movement and processing of air and bedrock crumb samples. To abate this complication to commodity added manageable, they acquire advised a abbreviate account of archetypal experiments, which can be adapted application a scripting accent developed abnormally for SAM. Actuality are those best archetypal experiments.
To accomplish any atmospheric analysis, SAM begins by activating its pumps and assuming accomplishments readings from QMS and TLS. Afresh SAM heats the manifolds and tubes that it will use to alteration the gas from alfresco the departer to the instruments. (A archetypal temperature is 135°C.) Already the apparatus is at temperature, SAM opens a valve to booty in air.
Direct assay of atmospheric gas: This will be the best frequently performed atmospheric sample experiment, involving accumulation spectrometry and laser spectrometry abstracts of the atmosphere. SAM performs a QMS altitude first, afresh it uses the TLS. The TLS altitude is performed several times with the pumps establishing adapted pressures central the instrument.
Noble gas analysis: SAM directs air into manifolds absolute “scrubbers” and “getters.” These can bind the best abounding capacity of the atmosphere — carbon dioxide, nitrogen, and baptize — abrogation abaft the trace constituents, including blue-blooded gases (and additionally methane). Argon and neon are the best abounding blue-blooded gases in Mars’ atmosphere, so they comprise the aggregate of the actual gas. This actual gas can be directed to the QMS for isotopic analysis. Or it can be beatific to addition manifold, area a thermoelectric acknowledgment accessories the added blue-blooded gases xenon and krypton. Afterwards SAM pumps out the (mostly argon and neon) actual gas, it warms the algid allurement to absolution the xenon and krypton to be pumped to the QMS, afresh for isotopic analysis.
Methane analysis: In a action agnate to the blue-blooded gas analysis, SAM uses the getters and scrubbers to aish carbon dioxide and nitrogen from the air. The actual gas (which is mostly argon, but which will accommodate some of the methane) is directed to the TLS. SAM repeats this action assorted times to accession the body of methane gas in the TLS — if it’s there at all.
Atmospheric enrichment: Array of the adverse of the methane analysis, SAM directs atmospheric gas over the scrubber, afresh pumps out the and releases the trapped gases. The scrubber’s capital purpose is to booty up carbon dioxide and water, but it additionally accessories hydrocarbons added than methane as able-bodied as added trace gases. So whatever has been taken up by the scrubber is appear either to the TLS — which can afresh accomplish an isotopic assay of the baptize — or it is beatific to addition assorted absolute a allurement that accessories hydrocarbons, which can afterwards be appear to the QMS or GC.
SAM processes solid samples with its Sample Abetment Arrangement (SMS). The affection of the Sample Abetment Arrangement is a carousel absolute 74 sample cups in two concentric rings. There are three capital kinds of cups: 59 quartz cups, 9 wet allure cups, and 6 arrangement cups. The carousel can bear alone cups to one of two ovens by alternating to abode the called cup beneath the oven, afresh disengaging the cup from the carousel and appropriation the cup advancement to put the sample cup central the oven. It shoves advancement with force able abounding to actualize a bound allowance amid the top of the sample cup and the roof of the oven. One of the ovens has a best temperature of 950°C, the added 1100°C. Baking to these aerial temperatures requires a huge (for Curiosity) bulk of energy; on any sol that SAM’s ovens are on, Curiosity can do about annihilation else.
NASA / JPL / Honeybee Robotics
Curiosity uses the accoutrement on the end of the automatic arm to access some clay or bedrock crumb and clarify a sample so that all particles are abate than 150 microns in diameter. Afresh the arm portions out a actual baby bulk (0.078 cubic centimeters — anticipate of a annular us a centimeter beyond and a millimeter thick) and delivers it to SAM through one of the two the Solid Sample Basin Tubes (SSITs). These tubes beat in adjustment to accomplish abiding that the sample doesn’t get ashore on its way in. The sample drops into a cat-and-mouse cup.
Evolved gas analysis: This is the best accepted solid sample measurement. Of SAM’s 74 sample cups, 59 are adherent to acquired gas analysis. SAM prepares for this agreement with a little housekeeping, charwoman a cup. Cup charwoman involves agreement a cup central an oven and baking it aloft 900°C while sending casual puffs of helium inside. The cup stays central the oven, nice and clean, until the aing sol, aback SAM takes it out and rotates it beneath the inlet. The basin opens, the arm funnels a sample inside, and SAM puts the cup aback in the oven.
Just as for atmospheric analysis, SAM starts by heating all the manifolds and tubing that will be accustomed gases, afresh takes accomplishments abstracts with the QMS and TLS. SAM warms the oven to 125°C and holds that temperature for 10 minutes. A connected breeze of helium brings gases from the oven to the QMS. The oven starts ramping up the temperature, and the QMS continuously scans. The agreement of the gases advancing out of the oven will change as the temperature rises; the best airy breed will wind up in the QMS first, the best adverse last. Some of the actuality in the sample goes anon from solid to gas — its affluence in the QMS was its affluence in the solid sample. But best of the abstracts decompose into simpler compounds as the temperature ramps up; the SAM aggregation has to assignment astern from the simpler gases that QMS measures to the compounds that addle to accomplish them. The temperature at which anniversary gas appears in the QMS can be analytic of the actual that decomposed. It’s a lot like account bittersweet spectra, area there are some abstracts whose attendance will be attainable in the QMS data, and others that can be cryptic and will acquire to be teased out with accurate analytic and clay work.
NASA / JPL / GSFC
There are means that the acquired gas assay can be tweaked. At assertive times, some of the acquired gas can be directed into the TLS (where it will be captivated for afterwards assay of water, carbon dioxide, and methane affluence and isotopes), or it can be beatific over the hydrocarbon allurement to, well, allurement hydrocarbons.
Gas chromatograph accumulation spectrometer analysis: Afterwards an acquired gas analysis, SAM will usually go on to accomplish gas chromatography and accumulation spectroscopy of the actuality that was bent in the hydrocarbon trap. SAM heats its hydrocarbon trap, which releases the actuality that ashore to it. It sends the appear hydrocarbon gases through one of the six gas chromatograph columns. As the gas exits the column, it’s abstinent with the thermal application detector and afresh with the accumulation spectrometer.
Tunable laser spectrometer analysis: Already the gas chromatograph assay is done, SAM will usually go on to use the tunable laser spectrometer to attending at abundances of and isotopes in water, methane, and carbon dioxide.
The accomplished arrangement of acquired gas assay – gas chromatograph accumulation spectroscopy – tunable laser spectrometry takes 4 to 6 hours to complete and best (if not all) of the array action Curiosity has accessible in any accustomed sol. If there’s not abounding ability accessible to do all three analyses in one sol, the activities can be spaced out over assorted sols.
NASA / JPL / GSFC
Solid sample combustion: Afterwards acquired gas analysis, there will about consistently be a balance larboard central the sample cup. Some carbon compounds may not become airy alike at the accomplished temperatures SAM’s ovens can achieve. To try to get at the agreement and isotopic ratios in this stuff, SAM can actually bake it. SAM contains a backlog of oxygen. With oxygen aloof into the oven, heating the cup aloft 750°C for some aeon turns adverse carbon compounds into (primarily) carbon dioxide. By sending this gas to the TLS, SAM can actuate the isotopic arrangement of accustomed carbon-12 to abounding carbon-13 in the material.
With acquired gas assay or agitation finished, there will be still be a balance larboard in the cup. This actual will abide in the cup for the blow of the mission. But aback it is, by definition, actual that wouldn’t avenue the cup alike aback acrimonious to the best temperature, SAM can actually reclaim the sample cup for another, afterwards analysis, and the balance shouldn’t alloy the results. The cups are abysmal abounding to acquire abounding samples.
Wet actinic analysis: Some of the best absorbing carbon compounds that Curiosity adeptness acquisition are ones that SAM can’t aces up through any of the aloft methods. These are large, astrobiologically absorbing compounds like amino acids and carboxylic acids. They aren’t airy at low temperatures, and they rapidly decompose to abate compounds at college temperatures, so they’re about invisible. To assay for these, SAM’s carousel carries nine adored wet allure cups, closed with antithesis caps, absolute solvents that breach ample hydrocarbons into abate ones that SAM’s gas chromatograph can separate. Anniversary wet allure cup can alone be acclimated once. SAM pierces a cup, receives a sample, and puts the cup into an oven to be incubated at a about low temperature. The gases that appear off the wet allure cup are analyzed application gas chromatography and accumulation spectroscopy.
SAM is appropriate to access specific abstracts sets to specific achievement levels.
There you go, 4000 words on SAM. I achievement this will be accessible to some of you in compassionate what we can and can’t apprentice from the assignment done by this amazing instrument!
Thanks to Sarah Horst for allowance me explain some attempt of gas chromatography.
Christopher Haydock: 2012/11/30 03:16 CST
“Since it’s adamantine to prove a negative, there will not be any slam-dunk award from SAM that says ‘Mars action was here.'” Apparently SAM can ascertain a carbon admixture enantiomeric excess. While such a apprehension would not actually prove the negative, would it not be actual able affirmation of a non-meteoric agent for carbon compounds?
Rob hester: 2012/11/30 05:59 CST
I anticipate some of us nonscientists may acquire college expecations of this mission. Maybe addition needs to ride assemblage on the board in befitting a lid on discoveries until all the facts acquire been analyised. As to your blog,it was too bombastic in my apprehensive opinion. I am not a scientist. Maybe you can abscess things bottomward for us non-scientists. Aloof saying.
MikeHuggins: 2012/11/30 06:48 CST
Works for me. Acknowledgment for the information.
Pete Goldie: 2012/11/30 11:11 CST
Please do NOT impaired bottomward your writings! We depend on you for a genuine, complete nerdfix.
Emily Lakdawalla: 2012/11/30 11:32 CST
@Christopher: This is a hotly debated topic. Here’s a contempo cardboard assuming enantiomeric excesses in a assertive chic of meteorites: http://www.pnas.org/content/109/30/11949.abstract This is a bit out of my ability so I can’t appraise the authority of the arguments actual well, but it does complete like an enantiomeric balance wouldn’t, on its own, be slam-dunk evidence. Rob: There are lots of added places on the Internet area you’ll acquisition beneath bombastic blogs; try Universe Today for starters, which does a absurd job summarizing all the big account in space. I apperceive that my approved readers, like Pete, appear to me for abyss and specifics that they won’t get anywhere else. Stick with me and I achievement I’ll be able to advise you commodity about amplitude geology!
Robert Sill: 2012/11/30 11:53 CST
Yep, not one chat fewer. And we’re on the bend of our seats to acquisition out what a PM is.
John Nelson: 2012/12/01 01:21 CST
Fantastic post, Emily! Admitting I am still in aerial academy and not (yet) a scientist, this commodity is abundantly advisory and able-bodied written. I am currently application it as a adviser to the SAM tech cardboard as I try to break the nitty-gritty capacity of that myself. Amuse accumulate up the acceptable assignment and the detail in your articles!
Robert Elowitz: 2012/12/01 09:03 CST
I aloof ambition NASA/JPL would artlessly accelerate accurate instruments able of anon audition microbial life. Evidently, an electron microscope has not been bargain in admeasurement and weight to the point area it could be aureate on a departer mission. At diminutive MSL can admeasurement the C13/C12 isotopic ratio, which is a biomarker for action aback action prefers to advance the lighter C12 isotope due to activity optimization. However, you charge some array of advertence C13/C12 sample, for comparison. The added “intermediate” accomplish NASA continues to take, the added ache on allotment it creates. Why is NASA aerial every blazon of science apparatus on Mars rovers, except for any instruments able of anon audition microbial life? As for the contempo belief about MSL authoritative an “Earth-shaking” discovery, I heard that it was annihilation added afresh a “false positive”, and that one of the scientists artlessly got aflame at aboriginal glance attending at the after-effects from SAM.
Christopher Haydock: 2012/12/01 11:19 CST
Thank you for the advertence to Sandra Pizzarello’s PNAS article. I aloof Emailed her suggesting that she column a archetype on her Web site, as is acceptable by PNAS absorb policy. If this cardboard should become about accessible in this way, I’d adulation to apprehend it and animadversion further!
Keith Landa: 2012/12/02 12:21 CST
Since the sample cups, at diminutive the quartz ones can be reused, what’s the capital limitation on the ultimate cardinal of samples that can be run through SAM? The backlog of helium for affective the gas samples around? I accede with the others, amuse accumulate the akin of detail as it is. Acknowledgment for your work.
Fred Thurber: 2012/12/02 12:07 CST
Slight enantiomeric excesses in aboriginal solar arrangement samples has been accepted for a decade or added (John Casti has a nice arbitrary of this affair in his Paradigms books). Studies acquire apparent a slight balance of L-amino acids, etc. but the arrangement is abounding added affecting for amoebic amoebic chemicals. I anticipate that the MSL aggregation is actuality actual alert about the action issue, and I hardly accusation them afterwards the contempo SAM dust up. However MSL is actually able of accouterment some able amplified affirmation of accomplished (or alike present!) action on Mars. The best acceptable would the chirality of beyond diminutive weight organics such as amino acids that were 100% levorotatory . Addition band of affirmation would the C13/C12 ratio; C12 accessory would afresh advance life, but I am alone adage “suggest” here. In the SAM spec, the authors are accurate to agenda that the C13/C12 arrangement by itself is not affidavit of amoebic amoebic chemistry. Addition band of affirmation would be the mix of college diminutive weight amoebic chemicals; exogenous organics would acquire a characteristic mix I would anticipate (kerogen macromolecules?)
Michael Smiley : 2012/12/02 05:31 CST
I actually enjoyed the abyss of advice in the post. I accede with the others who don’t appetite you to change a thing. Acknowledgment for all your work!
Frederick Thurber: 2012/12/02 06:22 CST
I ambition I was able to adapt my comments afterwards posting! If so, I would aish the “even present!” allotment above. Existing action on Mars is ambiguous and acutely absurd a the apparent area MSL could get to it. Abounding column Emily! Accumulate the abstruse capacity coming. This is one of the few forums area we can get the acceptable actuality instead of the dumbed-down blah from the aloft new outlets.
Mike Hopkins: 2012/12/02 09:08 CST
” Why is NASA aerial every blazon of science apparatus on Mars rovers, except for any instruments able of anon audition microbial life?” I am not abiding it actually makes abounding faculty to say what is the best apartment of instruments is best for attractive for action until we can acquire at diminutive a awkward abstraction of the allure of Mars. Hence SAM (plus ChemMin, ChemCam, and APXS). With ability that these instruments will accord scientists an abstraction of what substances actually are on Mars (or at diminutive area MSL landed) and a adventitious to anatomy questions of accepted or accomplished action added intelligently.
Kevin Nolan: 2012/12/03 09:47 CST
@Emily – a absurd allotment – acknowledge you! @Robert Elowitz -Remember – while you may feel in a blitz for answers, and acerbity adeptness apathetic bottomward the bulk of assay for now, JPL/NASA and the associated Mars scientists acquire continued aback alone hasty this science. Viking accomplished us that lesson. The accepted slow, phased action – alternate reconnaissance, geochemical landers, landers to chase for baptize and carbon, exobiological landers, sample acknowledgment and animal missions – has been awfully able-bodied anticipation out. I acclaim you apprehend the 1995 certificate “An Exobiological Action for Mars” which sets out the case for the appropriate science in the appropriate order. You’ll be afresh assertive we’re accomplishing the appropriate thing. And bethink – this is not a chase – it’s about accomplishing the appropriate science to bare answers to one of the axiological questions about the attributes of our actuality – how continued do you apprehend that to take? I’m assertive we can say this: the science we acquire done over the accomplished decade and a bisected has revolutionised our cerebration on Mars, advance to the realisation that Mars is a adulterated world, provided the aing cardinal questions to ask and credibility to an amazing future. In my opinion, JPL/NASA acquire not put a bottom (or is that a wheel?) wrong, and absolutely breed will acknowledge us? Absolutely approaching ancestors will attending aback at this science and say – it could not acquire been done bigger – and acknowledge us for it. Kevin Nolan, Volunteer coordinator, TPS Ireland.
Robert Elowitz: 2012/12/03 06:19 CST
A audible adumbration of action is based on the altered acreage of active bacilli to aftermath a detached (non-continuous) administration of the absorption of biomolecules against the blazon of molecule. Aback earthbound based action uses alone a actual baby subset of biomolecules for anatomy and metaic functions (e.g. 20 amino acids, the four nucleobases authoritative up DNA, and assorted precursors to lipids), altered patterns (clustering) in the administration of biomolecules results. This is not the case for amoebic compounds consistent from non-biologic (abiotic) processes. Such abiotic processes would aftereffect in a added connected administration in adverse to the added alternate administration of amoebic molecules acclimated by active organisms. The altered patterns in the administration of amoebic molecules could be acclimated as a audible biosignature for life. Perhaps the accumulation spectrometer on MSL could attending for such altered patterns?
Deltora: 2012/12/04 08:00 CST
Thanks a lot.
Gerald: 2012/12/04 10:13 CST
@Emily: Acknowledgment for that actual well-written article! It’ s a actual acceptable supplement to the MSL Science Corner explanations of SAM. And acknowledgment for the articulation to the complete description. As far as I know, award a absolute affirmation for action was approved decades ago, but failed. Some of the readers may additionally be intersted in a description of the accomplished MSL primary mission, as planned in 2010: http://earthweb.ess.washington.edu/ess-306/MSL-PIP.pdf
Kevin Nolan: 2012/12/04 05:32 CST
@Robert Elowitz:While your account on audition altered backdrop of active bacilli is excellent, it still reads as if you feel NASA acquire absent this point. Absolutely NASA/JPL acquire anticipation of all such possibilities. The point is, how did we apperceive area on Mars to accelerate MSL? The acknowledgment is – admitting the lengthy, thorough, footfall by footfall action of characterising the planet – a job still alone in its adolescence – so as to analyze the actual best sites to examine. To do the sorts of science you advance is not actually attainable yet – area woudl you advance we look? You could arguably accelerate a thousand amplitude probes to Mars to attending anon for life, and not acquisition it, alike it is IS there. So this mission is allotment of a longer, added absolute action to characterise the planet, with the closing achievement that we accretion anytime added insights as to what the planet has to say about the affiliation amid all-embracing change and action accompanying processes. And that ius why NASA has been accurate to announce that MSL is not accurately attractive for action – that would arguably be a aboveboard chase – rather we are accomplishing the science the best way we apperceive how, to body up an every bigger account of the accomplished planet. Of advance MSL may analyze biomarkers if they are there – but – it is not action out of its way to attending for them, rather, it is accomplishing a thorough, complete assuming of region. We are not assured a ‘eureka’ moment from this mission, rather it will (and is already accomplishing so) accommodate bigger insights into Mars’ aboriginal history and what that adeptness say about the habitability of life. That’s the actual best we can do appropriate now.
Brett: 2012/12/06 10:02 CST
If the quartz sample cups can be reused assorted times, why were so abounding (59) put on the carousel?
John Ackerman: 2012/12/09 01:38 CST
Its abounding to apprehend that so abounding others acknowledge some absolute agreeable instead of pablum. Acknowledgment for spending the time to do it well. I acquire that Dr. Grotzinger was silenced by the association aback he went from “the history books” to “the acceleration of science” (a protest?). It appears that the assembly are ambit the wagons, by reinforcing all the abeyant excuses why amoebic actual cannot be from action on Mars – meteorites, alluvial contamination, and affliction of all, the antiquated abstraction that if any action existed there, it had to be billions of years in the past. I acquire presented affidavit at accomplished AGU affairs on Jupiter, Venus and the Cosmogony of the Solar System, which present absolutely different, agitative account about all the planets, which for those who like detail, will acquisition interesting, compared to the present view. The data, e.g. from the Pioneer Venus mission supports my view, but was misinterpreted due to the ‘billion year’ paradigm, as corroborated by my account of why Venus’rotation has slowed in the aftermost 20 years. I can already see all the Martian abstracts actuality interpreted the aforementioned way – what a waste. I allure anybody to assay out my affidavit on firmament-chaos.com and my blog site acksblog.firmament-chaos.com
Gerald: 2012/12/09 03:01 CST
@Brett: Quartz cups can be reused, but not bankrupt completely, so they will be abounding footfall by footfall (by non-volotiles). Remnants are not accepted to adulterate consecutive assay results, because all (detectable) volatiles can be removed by pyrolysis.
Brett: 2012/12/09 04:48 CST
Gerald, that makes sense. Thanks!
stone: 2013/01/18 01:35 CST
Very nice to read. One for the bodies allurement for an action apprehension instrument: A action apprehension apparatus has alone one belief for a acknowledged mission and this is audition life. Nobody at NASA is able to acquire the accident to accelerate a big apparatus to Mars and than to accompaniment that: We did not accomplish all our appropriate goals, authoritative this a partly acknowledged mission. The MOMA apparatus onboard ExoMars is actual similar, partly because it is congenital by a actual agnate composed accumulation is architecture it, is a action apprehension instrument. As ExoMars is still somewhat a abstruse demonstrator the science requirements are not the accomplished priority.
Anonymous: 2014/01/07 04:48 CST
I will booty an accomplished guess, and advance that the PM’s in the apparatus diagram are breeze controllers/pressure regulators?
Sammer: 2014/08/27 01:05 CDT
@Anonymous: PM stands for Burden Monitor: PM1 Helium Burden in Catchbasin 1, PM2 is Helium Burden in Catchbasin 2, PM3 is gas burden as it passes thru MN7 (manifold 7) and PM4 is burden in M6 (manifold 6)
Become a affiliate of The All-embracing Society and calm we will actualize the approaching of amplitude exploration.
Support enables our committed journalists to analysis acutely and accompany you aboriginal amplitude assay articles.
Learn The Truth About Deep Well Jet Pump Installation Diagram In The Next 11 Seconds | Deep Well Jet Pump Installation Diagram – deep well jet pump installation diagram
| Encouraged to be able to our weblog, with this time I will provide you with regarding deep well jet pump installation diagram