A CIVILIZATION on MARS? 1B/200M Years Ago? (Pt. 5)

JonClarke · Jun 13, 2005

Colin Good to see the discussion going back on track. Some problems with what you said. Earth and Mars were never mini gas giants. Even though it is possible, even likely, for methane to have been present, the work of people like Kasting etc. shows that they are still minor constituents, for earth between 200 and 3000 ppm by volume. That is less than 1%. While there is good evidence for glaciation at 2.3 Ga (the Gowganda) there is no reason I am aware of to suppose this was global. But then I am not a fan of snowball earths in any era. As I have told you before, there is no evidence I know of for a core dynamo on Mars after 3.5 Ga. Hesperian and Amazonian rocks lack evidence for a strong global field. Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

centsworth_II · Jun 13, 2005

"Ah, but there are photosynthetic bacteria. But that's just a technicality." Not just a technicality. Cyanobacteria are presumed to be responsible for Earth's original atmospheric oxygen. See Introduction to the Cyanobacteria: Architects of earth's atmosphere <div class="Discussion_UserSignature"> </div>

JonClarke · Jun 14, 2005

Hi Colin All excellent questions. In fact, there is evidence that the core is still liquid. This is based on data from precession and tidal data. With respect to the core the issue is not that it solidified by 3.5 Ga, but that it stopped generating a strong magnetic field at that time. The two are not the same. Convection have have been too sluggish or too disorganised to generate a strong dynamo, or the core may have gone through a change in equilibrium, resulting in heat transfer by some other means such as conduction. As to why this might happened faster on mars than on earth, I am not sure. Maybe Mars has less radioactives than earth, I am not sure if the bulk composition is well enough constrained to say much about this. It is certainly an area for further research. Regarding the impact of the loss of a core dynamo on surface processes I don't see why this should have had any short term impact. Loss of a strong magnetic would lead long term to great atmospheric loss because of solar wind erosion, but this would be a gradual process. This is consistent with the evidence for at least episodic standing water as well as outbursts in the Hesperian but only outbursts in the Amazonian. Wind activity of course continues through to the present. Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

yevaud · Jun 14, 2005

Jon: It's understood that Mars differentiated - and cooled - faster than Earth did. Notwithstanding the data on the presence of a liquid core, one wonders if this has some bearing on the absence of a Geomagnetic field at this stage of Martian planetary evolution. <div class="Discussion_UserSignature"> Differential Diagnosis: "I am both amused and annoyed that you think I should be less stubborn than you are." </div>

mental_avenger · Jun 14, 2005

Most of these questions cannot be accurately answered with true or false. <ul type="square">Hyp 1: Mars has carried significant volumes of Liquid Water in the past which is a potential basis of a life evolution process. True/False? </ul> Not enough information. It depends on how much water was available, and exactly when it was available. It also depends on the purity and/or salinity of the water. <ul type="square"> Hyp 2: Such Water on Mars in the past may have constituted large-scale oceans and seas forming an even larger basis of a life evolution process. At one point, a global ocean may have covered Mars expect for Olympus Mons and other high points. True/False? </ul> True, that is “possible”. <ul type="square">Hyp 3: Mars may have had a remarkably lower incidence of Asteroid/meteor Bombardment than did Earth (perhaps 75% fewer hits) due to arguments about the 'target size' of Mars vs Earth. And thus Mars may have had 25% of the mass extinctions that Earth had - forming another basis of an early and more rapid life evolution process. True/False? </ul> True, that is “possible”. But it is also possible that it got as many hits per surface area as Earth did. Also, evolutionarily speaking, advancements of some of the higher species may have actually been aided by mass extinctions. That would make fewer bombardments less favorable to advanced life, or possibly even lower life forms. <ul type="square">Hyp 4: The Differential Gravity between Mars and Earth (Mars has 40% of Earth gravity) may argue that evolution might occur on Mars at a more rapid rate than on Earth. Or a life evolution process which required, say, 3.o billion years on Earth, might be truncated on Mars into 2.o billion years. True/False? </ul> Not enough information. While that may be “possible”, I have never seen any evidence to support that conjecture. <ul type="square">Hyp 5: Earth and Mars may have had primordinal Atmospheres of Hydrogen (argued in a recent jour</ul> <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

a_lost_packet_ · Jun 14, 2005

To whom it may concern, I'd like to direct your brief attention to two posts I created in the "A Question about Cydonia" thread. I believe, in the light of recent postings, that the argument is now at a close in regards to the question of Cydonia's "artificiality." A Question about Cydonia Thank you for your consideration. (p.s. I'm not overly fond of c+p'ing my own posts crossthreaded. It gets messy.) <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

JonClarke · Jun 14, 2005

Steve Cynaobacteria are a subdivision of the kingdom of bacteria. In addition to the chlorphyll-bearing cyanobacteria, a number of other bacterial groups are also photosynthetic, although not oxygen releasing. Fungi, algae etc., are all eukaryotic organisms, with organelles, cell nucleii, etc. they have their own kingdoms. The chloroplasts of all photosythetic eukaryotes have their own DNA and are probably descended from symbiotic cyanobacteria-like bacteria. It is also worth noting that corals (as per your second post) are not of themselves photosynthetic, but contain symbiotic photosynthetic microorganisms. This zooanthellae also occur in the larger foraminfera (which really stretch the definition of unicellular to breaking point, sponges, and molluscs. No multicellular animals of themselves are photosynthetic. It is rare even amongst the even the unicellar ones, the Eugleniids being an exception, although they are facultive rather than obligatory photosynthetes. Jon Added in edit: Stromatolites are constructed largely by cyanobacteria, in many cases along with a whole zoo of other organisms. <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

JonClarke · Jun 14, 2005

Colin: Do you have a source for saying that mars differeniated more quicly than earth? It think it is true that the two differentiated differently, because of the moon-forming impact on earth. There are relicts of highly differentiated terrestrial crustal minerals (zircons) in the Yilgarn as old as 4.3 Ga. Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

JonClarke · Jun 14, 2005

Steve Certainly most bacteria taxa are not photosynthetic. But cyanobacteria are extremely common in the sea, in lakes, rivers, and soils, and as symbionts in other organisms. Their biomass is much more significant than their number of taxa might suggest. They were the only source of oxygen through in the Archaean and Palaeoproterozoic, which is more than half the history of the earth. Cyanobacteria have been recognised as bacteria for at least 40 years, which is why people have stopped calling them blue green algae (although the name persists, especially in the popular mind). Whether you use the five kingdom (animals, plants, fungi, protists, bacteria or the three empire (archaea, bacteria, eukaryotes) classification, they are classed as bacteria. The dominant organism forming stromatolites are cyanobacteria. This is thought to have been the case for most of the Archaean and Protrerozoic stroms for example. It is certainly the case for stroms in modern salt lakes. However other organisms can play a role. There are non-photosynthetic bacterial stroms for example, in caves and deep water environments. Archean construct stroms in hot springs. The Shark Bay stroms that you mention, and which I have visited on several occasions, are constructed by a whole community. Cyanobacteria are the dominant group, but they also contain filamentous green algae and diatoms, and their surfaces are colonised by calcareous green algae. Certainly zooanthellate organisms show very close relationships with their symbionts. However they are corals do expell their symbionts when stressed (coral breaching is this process) and can survive. More importantly all zooanthellate organisms have close relatives which are not - deep water scleractinian corals, for example. So it is better to regard zooanthellate organisms as symbiosis rather than as separate taxa. Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

JonClarke · Jun 14, 2005

Sorry Colin That was Yevuad. My apologies. Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

yevaud · Jun 14, 2005

I almost posted that in response, this afternoon, but I wasn't certain. Mars: around 50% the mass / size of Earth. How could it *not* have differentiated and cooled faster? And to my understanding, the large amount of pyrites at or on the surface of Mars was supposed to be good visual evidence of it. <div class="Discussion_UserSignature"> Differential Diagnosis: "I am both amused and annoyed that you think I should be less stubborn than you are." </div>

JonClarke · Jun 14, 2005

Interesting stuff indeed, but it is too early to say whether lower gravity is a help or hinderence to evolution. testing the hypothesis is what is going to be very hard. Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

centsworth_II · Jun 14, 2005

"These bacteria explode and convert the methane and hydrocarbons to a massive rich 02/H20 atmosphere." -- colin098 An explanation of how bacteria create O2 from hydocarbons would be appreciated. Without resorting to photosynthesis, of course. <div class="Discussion_UserSignature"> </div>

JonClarke · Jun 15, 2005

Got in one Steve The Yilgarn is the largest Archaean craton on the contient. It occurs in Western Australia and hosts many world class deposits of gold and nickel. The zirocn ages are well confifmed, the are from using the ion microprobe which can date individual growth zones in a small crystal. It is the most accurate method for dating Archaean rocks with accuracies of the order of 1% Jon The Canadian cherts you mentioned are the Gunflint cherts, I suspect. <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

JonClarke · Jun 15, 2005

Microfossils have been found in Palaeoproterozoic and Achaean silicified stromatolites that are morphologically very similar to cyanobacteria. I understand that there are also biomarkers (geochemical fossils) of cyanobacteria) in rocks this age as well. But taxonomy is certainly an evolving subject <img src="/images/icons/smile.gif" /> Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

JonClarke · Jun 15, 2005

Steve What's your source for stating that earth is overal richer in heavy metals (and which ones) than Mars or Venus? Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

najab · Jun 15, 2005

Steve said: "Stromatolites are created by algae, as they are created today by algae. The similarities between those of today near australia as I recall versus those fossil stromatolites a billion years old or so, are too much of a coincidence to be ignored, anyway." Then Steve said: "There are simply no confirming fossils existing, and similar in appearance does not mean they are even related. Esp. at billions of years in the past." I say: <img src="/images/icons/rolleyes.gif" />

JonClarke · Jun 15, 2005

Max asked me some time ago to comment on a paper by James L Eravec and Ronald R Nicks. It was: A GEOLOGIC/GEOMORPHIC INVESTIGATIVE APPROACH TO SOME OF THE ENIGMATIC LANDFORMS IN CYDONIA The original source is obscure “The Monuments of Mars” by RC Hoagland (5th edition) variously 2001/2002, it also apparently appears in “The Case for the Face” (edited S. V. McDaniel and M. R Paxson,1998). The first edition of “Monuments was 1985/1986, I don’t know if it appeared in that. Can someone check, if they have an early edition? The paper contains no reference to any imagery other than Viking so could be quite old. The newest reference is 1994. Similar material may have appeared in Erjavec, J. and Nicks, R., "Geological Analysis of Enigmatic Landforms in Cydonia," in The Martian Enigmas, A Closer Look, North Atlantic Books, Berkeley CA, p. 67-86 (1997). The document pasted by Max appears to be an uncorrected scan, with some errors (as is common with scans). I have taken the liberty of editing these for clarity, when I can. References past “M” appear to be missing (e.g. Parker, Phillips, Tanaka, Torun, Wilhelms & Baldwin) Max posted the paper at this post and this post. I cut and pasted this into a word document for easier reading and work. It is 10 pages long, so when I added comments it becomes much longer. So, to spare everyone here, I will just summarise. Basically the paper is very poorly organized, without clear presentation of fact or separation of interpretation from speculation. It is also very badl <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

JonClarke · Jun 15, 2005

Thanks najab <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

JonClarke · Jun 15, 2005

Yes, this I might agree with. Overall I suspect earth, mars and venus have a similar chondritic composition. However the earth has undergone a form of differentiation unknown on the other two, the formation of continental crust. Arange of lithophile elements have been concentrated in that crust, including Al, Ti, U, Th, Ni and P which are all of economic interest, as well as Na, K, and Ca. Chalcophile elements assocated with ocean crust and mafic rocks (Cu, Zn, Pb, Au, Ni, Ag, Cr in particular). Any ore deposits on Mars will probably be of the chalcophile suite. Jon <div class="Discussion_UserSignature"> Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars Arthur Clarke </div>

yevaud · Jun 15, 2005

As one moves outwards from the inner planets (rocky, metal-rich) to the outer (gas giants, metal poor but hydrogen-rich), there must be a region of transition. Perhaps Mars is actually well over the line, so to speak, where metals are predominating less and less. The point about metals and life is quite interesting. There was a piece back when - and I can't for the life of me remember where I read it - about the importance of metals in the formation of the earliest life. Something to do with the metallic lattice provided made an ideal place for life to cling. And also something about the metallic shapes assisting in life's chiral nature (handiness), as those metallic shapes tended toward the same left-handedness as we see predominating now. <div class="Discussion_UserSignature"> Differential Diagnosis: "I am both amused and annoyed that you think I should be less stubborn than you are." </div>

centsworth_II · Jun 15, 2005

According to this quote from your Snowball Earth reference, the oxygen spike was caused by photosynthetic bacteria. "According to Kirschvink and his team, the planet froze over for tens of millions of years, but eventually thawed when a greenhouse-induced effect kicked in. This warming episode led to the deposit of iron formations and carbonates, providing nutrients to the blue-green algaethat were waiting in the wings for a good feeding. The algae bloom during the melting period resulted in an oxygen spike.... From Introduction to the Cyanobacteria,Architects of earth's atmosphere: "Because they are photosynthetic and aquatic, cyanobacteria are often called 'blue-green algae'" It looks to me that we are talking about the same means of oxygen production: photosyntesis by cyanobacteria. Only the environmental circumstances leading to it are being debated. <div class="Discussion_UserSignature"> </div>

centsworth_II · Jun 15, 2005

From your ASTRONOMY magazine quote: "One theory suggests that cyanobacteria - bacteria that give off oxygen - increased to the point that they saturated our atmosphere with oxygen. With the rise of oxygen, no matter the source, methane-producing microbes and atmospheric methane were wiped out..." I would say this is more than just "one theory". It is THE theory that fits the current fossil and geologic evidence. The Snowball Earth senerio may contradict some mainstream theories in other areas, but as regards the development of Earth's atmospheric oxygen, I would say it gets back into the mainstream. Also, a reminder: "bacteria that give off oxygen" do so through photosynthesis. <div class="Discussion_UserSignature"> </div>

mental_avenger · Jun 15, 2005

I can’t believe this thread is still going on. Isn’t there an upper limit on the number of times you can rehash the same old arguments? According to Kirschvink and his team, the planet froze over for tens of millions of years, but eventually thawed when a greenhouse-induced effect kicked in. That’s good. A “greenhouse-induced effect” just “kicked in”. No mechanism, no impetus, no prime mover, it just “kicked in”. This caused the manganese to be laid down in a huge 45-meter-thick deposit in the Kalahari to await future human mining and metallurgy. Again, no reasonable mechanism is proposed for such an improbable and unlikely occurrence. The layer was just “caused” to be “laid down”. Presently, it's an ultimately revolutionary set of ideas. I’d say unfounded, baseless conjecture. Some people might consider that to be “revolutionary” in a field that is supposed to rely on actual science. <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

mental_avenger · Jun 15, 2005

Therein, the ozone-shield in the atmosphere would have declined - You keep saying that, but what evidence do you have that there ever WAS an “ozone layer”? BTW, 50% greater than 25% of the Earth level seems an odd way of expressing a relative quantity. <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

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