...analysis of the Martian atmosphere that raises the possibility of life or geologic activity...

centsworth_II · Jan 12, 2009

"NASA<div id="preLoadLayer0" style="display:none"><img src="http://kona.kontera.com/javascript/lib/imgs/grey_loader.gif" alt="" /></div> will hold a science update at 2 p.m. EST, Thursday, Jan. 15, to discuss analysis of the Martian atmosphere that raises the possibility of life or geologic activity.... carried live on NASA Television."   <div class="Discussion_UserSignature"> </div>

a_lost_packet_ · Jan 12, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'> "NASA will hold a science update at 2 p.m. EST, Thursday, Jan. 15, to discuss analysis of the Martian atmosphere that raises the possibility of life or geologic activity.... carried live on NASA Television."   Posted by centsworth_II</DIV>Methane update I would assume?  Previously natural mechanisms thought to contribute to it may have been falsified by recent data? <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

centsworth_II · Jan 12, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Methane update I would assume?  Previously natural mechanisms thought to contribute to it may have been falsified by recent data? Posted by a_lost_packet_</DIV> It doesn't look like they are distinguishing between whether the source would be biologic or geologic.  Just pinning down the presence of methane and maybe some specifics concerning amount and time or site variations would be plenty.  I don't think that up til now it's even been generally accepted that previously announced methane "detections" are reliable.  If I recall correctly, this is the first time that a methane announcement (if that's what it is) has been made at a NASA press event.  If I'm not mistaken, previous announcements have been by individual science teams.  Also, it bothers me that photochemical sources are seldom mentioned in relation to methane.  It's quite possible that any methane source on Mars is largely photochemical in nature and not biologic OR geologic....  Just ask Silylene. LOL <div class="Discussion_UserSignature"> </div>

a_lost_packet_ · Jan 12, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>It doesn't look like they are distinguishing between whether the source would be biologic or geologic.  Just pinning down the presence of methane and maybe some specifics concerning amount and time or site variations would be plenty.  I don't think that up til now it's even been generally accepted that previously announced methane "detections" are reliable.  If I recall correctly, this is the first time that a methane announcement (if that's what it is) has been made at a NASA press event.  If I'm not mistaken, previous announcements have been by individual science teams.  Also, it bothers me that photochemical sources are seldom mentioned in relation to methane.  It's quite possible that any methane source on Mars is largely photochemical in nature and not biologic OR geologic....  Just ask Silylene. LOL Posted by centsworth_II</DIV>

IIRC, the problem is one of replentishment, if it does indeed exist in decent quantities.  The mechanisms proposed for replentishing methane were sort of mixed.. some having good possibility, some more likely but having less impact.  I'm not up on all that atm so can't be sure.  But, I guess I have some time to study up before the lecture!

Edit - What I'd like to see is an announcement saying that they have made sufficient analysis of various regions to rule out certain natural processess which could contribute to the detectable and, obviously, replentished methane presence in Mars atmosphere.Of course, it could be a last ditch bid to draw some press before Obama gets in office and threatens to combine their operations with the Military.  After all, who'd put them in OD green locker rooms with the smell of stinky sweatsox and borscht when they're right on the cusp of a major scientific discovery!!!  (That's my pessimism showing through.  I DO respect those great people over at NASA and don't mind if they do a little self-preservation work if they want to.) <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

h2ouniverse · Jan 12, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>, it bothers me that photochemical sources are seldom mentioned in relation to methane.  It's quite possible that any methane source on Mars is largely photochemical in nature and not biologic OR geologic....  Just ask Silylene. LOL Posted by centsworth_II</DIV> hi centsworth,Photochemical? Mmmm... would suit imho a global methane detection. But how can one get heterogeneous methane detection if photochemistry is the cause? Shouldn't it be uniform over Mars in that case (at least at iso-latitude)?

rlb2 · Jan 12, 2009

Oooops wrong post. <div class="Discussion_UserSignature"> Ron Bennett </div>

nimbus · Jan 13, 2009

Thanks for the heads up.  I'm gonna miss it.. Will it be rerun? <div class="Discussion_UserSignature"> </div>

centsworth_II · Jan 13, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>...how can one get heterogeneous methane detection if photochemistry is the cause? Shouldn't it be uniform over Mars in that case (at least at iso-latitude)?  Posted by h2ouniverse</DIV>If UV radiation and CO2 were uniform, the critical factor would be the presence of a catalyst. Whatever that catalyst may be, it may not be distributed uniformly.  EDIT: Oops.  Forgot the H2O.So... Sunlight, CO2, H2O, and a catalyst.  The right combination of all four of these to create methane could well be limited to specific regions on Mars. <div class="Discussion_UserSignature"> </div>

MeteorWayne · Jan 13, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Thanks for the heads up.  I'm gonna miss it.. Will it be rerun? Posted by nimbus</DIV> I should be able to watch; I'll let you know what they say about replays. In any case, there's usually a press release afterward, I'll take some scribblenotes, and I'm quite sure Emily Lakdawalla's Planetary Society blog will have plenty of details. <div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

nimbus · Jan 13, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>I should be able to watch; I'll let you know what they say about replays. In any case, there's usually a press release afterward, I'll take some scribblenotes, and I'm quite sure Emily Lakdawalla's Planetary Society blog will have plenty of details. Posted by MeteorWayne</DIV>Thanks, I couldn't ask for better than your scribblenotes

a_lost_packet_ · Jan 13, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Thanks, I couldn't ask for better than your scribblenotes

Posted by nimbus</DIV>I cant type at lightspeed but I can't get better than MW's scribblenotes.  My penmanship is ALWAYS suitable only for relative interpretation.. Sure, I can put ink on a page and understand it as I write it.  But, it seems I re-invent writing everytime I write because it's usually undecipherable when I finish.  (Thinking about it.. you know.. my writing is much better in pencil.  Maybe I just have a palsied writing style?  I'll have to think on that.)I'll be sure to read MW's scribblenotes as well even after seeing the conference.  He does a great job of reinforcing key points! <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

silylene · Jan 14, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>...Also, it bothers me that photochemical sources are seldom mentioned in relation to methane.  It's quite possible that any methane source on Mars is largely photochemical in nature and not biologic OR geologic....  Just ask Silylene. LOL Posted by centsworth_II</DIV>Thanks for remembering my pet thesis on the origin of CH4 in the Martian atmosphere.  This is the first time I was actually able to open this thread.I would post here more often, but the Pluck_bluescreen_of_death prevents me from getting access anymore from my notebook pc  (which is the one I use nearly all the time except on weekends). <div class="Discussion_UserSignature"> petet = silylenePlease, please give me my handle back ! </div>

silylene old · Jan 15, 2009

Wow, I was able to get past the Pluck_Bluescreen_of_Death using the Livescience login.  I will have to try this more in the future!Anyways, it seems as if photochemical abiotic generation of methane is being ignored by some of the scientists being quoted in this article.  At least judging from the blaring headlines of The Sun  (which is just about National Enquirer quality): http://www.thesun.co.uk/sol/homepage/news/article2133475.ece   I do predict they are all going to have mud on their faces and reputation in the future, when we find no life, and instead confirm photochemical routes to methane generaation under Martian conditions.  This is becoming just as silly as some of the NASA scientitsts' claims of life on the ALH 84001 meteorite. .<h1 class="large sIFR-replaced">Life on Mars</h1><div class="clear-left">By PAUL SUTHERLAND Sun Spaceman <div class="padding-top-10 padding-bottom-10 clear-left"><div class="float-left">Published: Today</div></div></div><div class="clear-left"><img class="border-none" src="http://www.thesun.co.uk/img/buttons/btn-add-your-comments.gif" alt="rigTeaserImage" width="152" height="19" /> </div><h2 style="font-size:1.05em;line-height:1.05em" class="padding-bottom-7">ALIEN microbes living just below the Martian soil are responsible for a haze of methane around the Red Planet, Nasa scientists believe. </h2>The gas, belched in vast quantities in our world by cows, was detected by orbiting spacecraft and from Earth using giant telescopes.  <div class=" margin-top-5 margin-right-10 padding-bottom-5 float-left" style="width:380px"><img src="http://img.thesun.co.uk/multimedia/archive/00708/SNN1501A-380_708912a.jpg" border="0" alt="Discovery ... gas around Mars" title="Discovery ... gas around Mars" /> <div class="text-center">Discovery ... gas around Mars</div></div> Nasa are today expected to confirm its presence during a briefing at their Washington HQ. And the find is seen as exciting new evidence that Martian microbes are still alive today. To read more of our exclusive UFO stories click here.Some scientists reckon methane is also produced by volcanic processes. But there are NO known active volcanoes on Mars. Furthermore, Nasa has found the gas in the same regions as clouds of water vapour, the vital “drink” needed to support life.  <div class=" margin-top-5 margin-right-10 padding-bottom-5 float-left" style="width:380px"><img src="http://img.thesun.co.uk/multimedia/archive/00709/newPic_1617_jpg_709000a.jpg" border="0" alt="Mission ... probe on the surface of Mars" title="Mission ... probe on the surface of Mars" /> <div class="text-center">Mission ... probe on the surface of Mars</div> </div> Experts speculate that the methane is being emitted as a waste product by organisms called methanogens living in water beneath underground ice. And they would have to be alive today because the methane would otherwise have been lost from the Martian atmosphere.  <div class=" margin-top-5 margin-right-10 padding-bottom-5 float-left" style="width:380px"><img src="http://img.thesun.co.uk/multimedia/archive/00709/newPic_2118_jpg_709004a.jpg" border="0" alt="What a scoop ... Phoenix lander dug up chunks of ice last year" title="What a scoop ... Phoenix lander dug up chunks of ice last year" /> <div class="text-center">What a scoop ... Phoenix lander dug up chunks of ice last year</div> </div> John Murray — a member of the Mars Express European space probe team — believes the mini-Martians may be in a form of suspended animation and could even be REVIVED. He has found overwhelming evidence of a vast frozen ocean beneath the dust near the Martian equator where simple life could have thrived as microbes. Today’s briefing will feature a star panel of Mars experts headed by Michael Meyer, chief scientist for Nasa’s Mars programme. UK Mars expert Professor Colin Pillinger believes the methane can only point to the presence of life on the planet.  <div class=" margin-top-5 margin-right-10 padding-bottom-5 float-left" style="width:380px"><img src="http://img.thesun.co.uk/multimedia/archive/00709/newPic_5049_jpg_709069a.jpg" border="0" alt="Space neighbours ... Earth and Venus rise over Mars in mock-up" title="Space neighbours ... Earth and Venus rise over Mars in mock-up" /> <div class="text-center">Space neighbours ... Earth and Venus rise over Mars in mock-up</div> </div> His ill-fated Beagle 2 probe was carrying a laboratory that would have looked directly for such signs of life when it crashed on Christmas Day 2003. Prof Pillinger told The Sun last night: “Methane is a product of biology. For methane to be in Mars’ atmosphere, there has to be a replenishable source. “The most obvious source of methane is organisms. So if you find methane in an atmosphere, you can suspect there is life. “It’s not proof, but it makes it worth a much closer look.” Nasa’s findings confirm studies by Europe’s Mars Express probe, which has been orbiting the planet for five years and also reported signs of methane in 2004. Britain’s top space expert Nick Pope last night hailed the new evidence of life as “the most important discovery of all time”. He said: “What could be more profound than to know it’s not just us out there?  <div class=" margin-top-5 margin-right-10 padding-bottom-5 float-left" style="width:380px"><img src="http://img.thesun.co.uk/multimedia/archive/00709/newPic_195_jpg_709070a.jpg" border="0" alt="Expert ... Colin Pillinger" title="Expert ... Colin Pillinger" /> <div class="text-center">Expert ... Colin Pillinger</div> </div> "We’ve really only scratched the surface — it’s an absolute certainty that there is life out there and we are not alone. “If there is life on Mars then the logical conclusion is that there must be life elsewhere too. “If it’s happened here on Earth, then why shouldn’t it happen anywhere? The implication is this is a universal law. “Mars is very similar to Earth. It’s about the same size, it’s a rocky inner planet. “Most scientists believe it probably has liquid water which is almost universally agreed as the pre-requisite for life. I am certain there is other life in the Universe and, most likely, intelligent life.” The Red Planet has gripped the public imagination for more than a century as a possible home for aliens. But life could not survive on its surface because, unlike the Earth, Mars has no magnetic shield to protect it against deadly sun radiation. The planet resembles our own in many ways. It is made of rock, it has an atmosphere and weather systems.  <div class="grey-ad-line width-300 position-relative">Advertisement</div><div class="float-right width-300 padding-left-10 padding-bottom-10 padding-top-10"><img src="http://m1.emea.2mdn.net/viewad/697837/15-300x250_debenhams_mpu.jpg" border="0" alt="Click here to find out more!" /></div><div class="float-right width-300 padding-left-10 padding-bottom-10 padding-top-10">Although much smaller with a diameter of around 4,222 miles, Mars’ day is just 40 minutes longer than ours and its tilted axis gives it seasons. </div>Water has been found in the form of buried ice and scientists believe that two billion years ago, Mars was covered with liquid oceans. Proof that water is still on Mars came in 2007 when Mars Express used ground-piercing radar to study the region around the planet’s South Pole. Nasa’s latest lander Phoenix dug up chunks of Martian ice last year. It swiftly evaporated into the thin atmosphere. Nasa have controversially hit the headlines before for claiming evidence for Martians. In 1996, they said they had discovered fossilised organisms in a meteorite from the planet. But other scientists were sceptical. Today’s conference will be broadcast live online by NASA TV (www.nasa.gov/ntv) at 7pm. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center">- - - - - - - - - - - - - - - - - - - - - - </div><div class="Discussion_UserSignature" align="center">I really, really, really miss the "first unread post" function. </div> </div>

centsworth_II · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>...it seems as if photochemical abiotic generation of methane is being ignored by some of the scientists being quoted in this article.  At least judging from the blaring headlines of The Sun  (which is just about National Enquirer quality).... Posted by silylene</DIV> It's hard to take seriously a reporter who's byline reads: "Spaceman".  But I suppose one can be a serious journalist and have a sense of humor.Although I am intensely interested in the prospect of finding life on Mars, I am also interested in knowing the facts of the matter.  It disappoints me whenever the possibility of photochemical generation is left out of a discussion concerning possible sources of methane on Mars. It leaves me questioning the thoroughness of the discussion.<div class="row1" style="padding-bottom:1px"> </div> <div class="Discussion_UserSignature"> </div>

rlb2 · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Wow, I was able to get past the Pluck_Bluescreen_of_Death using the Livescience login.  I will have to try this more in the future!Anyways, it seems as if photochemical abiotic generation of methane is being ignored by some of the scientists being quoted in this article.  At least judging from the blaring headlines of The Sun  (which is just about National Enquirer quality): http://www.thesun.co.uk/sol/homepage/news/article2133475.ece   I do predict they are all going to have mud on their faces and reputation in the future, when we find no life, and instead confirm photochemical routes to methane generaation under Martian conditions.  This is becoming just as silly as some of the NASA scientitsts' claims of life on the ALH 84001 meteorite. .</DIV>Here is what methanogens do on earth, from Wikipedia.Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. They are common in wetlands, where they are responsible for marsh gas, and in the guts of animals such as ruminants and humans, where they are responsible for the methane content of flatulence. In marine sediments biomethanation is generally confined to where sulfates are depleted, below the top layers. Others are extremophiles, found in environments such as hot springs and submarine hydrothermal vents as well as in the "solid" rock of the earth's crust, kilometers below the surface. Methanogens are usually coccoid or rod shaped. There are over 50 described species of methanogens, which do not form a monophyletic group, although all methanogens belong to Euryarchaeota. Methanogens are also anaerobic. Although methanogens cannot function under aerobic conditions they can sustain oxygen stresses for prolonged times. An exception is Methanosarcina barkeri, which contains a superoxide dismutase (SOD) enzyme and may survive longer. Some, called hydrogenotrophic, use carbon dioxide (CO2) as a source of carbon, and hydrogen as a reducing agent. Some of the CO2 is reacted with the hydrogen to produce methane, which produces an electrochemical gradient across a membrane, used to generate ATP through chemiosmosis. In contrast, plants and algae use water as their reducing agent. Although most marine biogenic methane is the result of CO2 reduction, a small amount is derived from acetate (CH3COO-). Archaea that catabolize this for energy are referred to as acetotrophic or aceticlastic. Methylotrophic archaea utilize methylated compounds such as methylamines, methanol, and methanethiol as well. Methanogens play the vital ecological role in anaerobic environments of removing excess hydrogen and fermentation products that have been produced by other forms of anaerobic respiration. Methanogens typically thrive in environments in which all other electron acceptors (such as oxygen, nitrate, sulfate, and trivalent iron) have been depleted. In the deep rock they obtain their hydrogen from the thermal and radioactive breakdown of water. Methanogens have been found in several extreme environments on Earth - buried under kilometres of ice in Greenland and living in hot, dry desert soil. They can still reproduce from temperatures of 15 to 100 degrees Celsius.They are known to be the most common prokaryotes archaebacteria in deep subteranean habitats.Live microbes making methane were found in a glacial ice core sample retrieved from three kilometres under Greenland by researchers from the University of California, Berkeley, US. Another study has also discovered methanogens in a harsh environment on Earth. Researchers studied dozens of soil and vapour samples from five different desert environments in Utah, Idaho and California in the US, and in Canada and Chile. Of these, five soil samples and three vapour samples from the vicinity of the Mars Desert Research Station in Utah were found to have signs of viable methanogens. Some scientists have proposed that the presence of methane in the Martian atmosphere may be indicative of native methanogens on that planet <div class="Discussion_UserSignature"> Ron Bennett </div>

MeteorWayne · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>It's hard to take seriously a reporter who's byline reads: "Spaceman".  But I suppose one can be a serious journalist and have a sense of humor.Although I am intensely interested in the prospect of finding life on Mars, I am also interested in knowing the facts of the matter.  It disappoints me whenever the possibility of photochemical generation is left out of a discussion concerning possible sources of methane on Mars. It leaves me questioning the thoroughness of the discussion. Posted by centsworth_II</DIV> Pretty overhyped article, eh?I suspect the actual news conference will be more scientific and less speculative

I'll be scribblin' fast!! About 2 1/2 hours from now...MW <div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

silylene old · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Pretty overhyped article, eh?I suspect the actual news conference will be more scientific and less speculative

I'll be scribblin' fast!! About 2 1/2 hours from now...MW Posted by MeteorWayne</DIV> I agree it is hyped up!  (I said The Sun was National Enquirer quality).  Still, they do have quotes from space scientists who seem to consider only two possible sources of methane:  volcanic/geologic and biogenic.  they are ignoring the other possibility:  photochemical generation. Sloppy science.  Biogenic methane should be "press released' only if  the abiogenic sources can be excluded with data and science, and we positively find life which generates methane.  please recall that the press and the vast majority of the American public does not understand the difference between speculation, hypothesis, theory and law, and perhaps does not understand the difference between fact and fiction.As I said, here we go again, polywater and ALH 84001, and then the future lack of scientific credibility when we find no life which generates methane. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center">- - - - - - - - - - - - - - - - - - - - - - </div><div class="Discussion_UserSignature" align="center">I really, really, really miss the "first unread post" function. </div> </div>

tanstaafl76 · Jan 15, 2009

Perhaps it's Dark Life that we can't see but can infer its existence by virtue of observing methane <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-cool.gif" border="0" alt="Cool" title="Cool" />  <div class="Discussion_UserSignature"> </div>

paulscottanderson · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>I agree it is hyped up!  (I said The Sun was National Enquirer quality).  Still, they do have quotes from space scientists who seem to consider only two possible sources of methane:  volcanic/geologic and biogenic.  they are ignoring the other possibility:  photochemical generation. Sloppy science.  Biogenic methane should be "press released' only if  the abiogenic sources can be excluded with data and science, and we positively find life which generates methane.  please recall that the press and the vast majority of the American public does not understand the difference between speculation, hypothesis, theory and law, and perhaps does not understand the difference between fact and fiction.As I said, here we go again, polywater and ALH 84001, and then the future lack of scientific credibility when we find no life which generates methane. Posted by silylene</DIV>You can't base what will be said in the press conference on this tabloid article. Perhaps they have considered photochemical generation, we don't know yet. The data at this point may be better explained by geology or life, we don't know yet. There are several scientists speaking, not just Mumma. Let's just see what they say, then go from there... <div class="Discussion_UserSignature"> -----------------The Meridiani Journal a chronicle of planetary exploration web.me.com/meridianijournal </div>

ariesr · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>You can't base what will be said in the press conference on this tabloid article. Perhaps they have considered photochemical generation, we don't know yet. The data at this point may be better explained by geology or life, we don't know yet. There are several scientists speaking, not just Mumma. Let's just see what they say, then go from there... Posted by paulscottanderson</DIV> Seconded. Lets here it from the horses.I'd be dumfounded if they havent considered photochemical

MeteorWayne · Jan 15, 2009

OK, folks, broad brush scribblenotes, I'll go into a bit more detail later.First a brief comment; this shows how long science takes to get published sometimes. The news conference was based on data taken in January and March 2003, with followup during (Mars) spring 2006.It was reflecting an article in a current or upcoming Science magazine.The point of it all was that there is active methane emission on Mars. Some constraints were given on methane lifetime in the atmosphere; less that 4 years is assured, most likely less than one year. That is what indicates current processes that are emitting methane.(Photolysis takes centuries, while oxidation processes operate much faster, so that is indicated.)There is NO indication as to whether the source is geologic or biogenic, despite previous reports. The whole point is that there is confirmed active methane emission. That is all. It can not even be stated with any confidence whether the methane is being currently generated (from geologic or biologic activity) or is methane captured in the distant past (perhaps trapped in clathrates) that is being exposed and therefore releasing it's methane to the atmosphere.No coincident releases of volcanic gases have been seen yet which would indicate a specific geologic source, but not much has been ruled out by current observations.They hinted that they have more data under analysis, but it cannot be released at this time. Papers later this year.Currently, no orbiting Mars assets can help resolve the issue (if you recall Mars express can sample, and has detected methane, but that is full disk, while these observations pinpoint emissions from specific areas, mostly in equatorial regions). There is a map showing the locations, one is Nilla Fossae (sp?) which had been eliminated from the MSL landing sites due to it's altitude, but may now get back into the mix, especially considering the 2 year MSL delay.The Spring 2006 observations did not detect methane, so it appears to be a seasonal process.From what I gathered, the authors on the Science paper should be Mumma, Villenueva, et al.More in a few minutes...Heres an image which shows the methane emissions (without pinpointing the exact sources) <img src="http://sitelife.space.com/ver1.0/Content/images/store/10/1/2a90b603-dfb7-43e8-8168-afbc6a70fef5.Medium.jpg" alt="" />Here's a link to the NASA press release:http://www.nasa.gov/mission_pages/mars/news/marsmethane.htmlWayne  <div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

centsworth_II · Jan 15, 2009

Because the source seems to be subsurface, is this a nail in the coffin of the photochemical generation hypothesis?    <div class="Discussion_UserSignature"> </div>

silylene old · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>...The point of it all was that there is active methane emission on Mars. Some constraints were given on methane lifetime in the atmosphere; less that 4 years is assured, most likely less than one year. That is what indicates current processes that are emitting methane.(Photolysis takes centuries, while oxidation processes operate much faster, so that is indicated.) Posted by MeteorWayne</DIV>Thank you MW.Did they have data that photolysis takes 'centuries' or is this a conjecture?  Actually it would need to be a steady state effect:  methane is both being produced and being lost.  The concentration observed reflects the chemical kinetics of these two processes.The map of methane production shown (I recall we went over this before, in the pre-Pluck SDC, and indeed in the pre-crash SDC also!) gives the highest methane production in the Martian equitorial band.  This is exactly what would be expected if it were a photochemical process, since this would occure in the areas of highest irradiance.The photochemical process I posted, and gave mutliple references for, in these forums in the pre-pluck days (maybe someone can look up the threads) was a photoreduction of CO2 catalyzed on metal oxide dust surfaces.  The dusts (TiO2, for example, this works with several types of oxides) serve as catalysts for this effect.  in fact, I would expect areas in which the dust is uplifted due to winds or dust devils to expose more dust catalyst for methane photoproduction.  So you may see the highest rates where there is both high irradiance, and higher concentrations of exposed metal oxide dusts.  In fact, I once referenced a paper which found some atmospheric photoreduction chemistry occuring on the dusts from the soil surfaces in Chile'se Atacambra desert, which is a rather good stand-in for the Martian conditions.There is also a literature paper (maybe I can find it) which Jon sent me which relied on a direct photochemical mechanism using the high energy irradtion available in the upper Martian atmosphere.  Who knows, this may work too!Until i see more, I am very unconvinced of the need for a biogenic methane source.  i will await reading their paper to see how they dismissed photochcmeical generation. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center">- - - - - - - - - - - - - - - - - - - - - - </div><div class="Discussion_UserSignature" align="center">I really, really, really miss the "first unread post" function. </div> </div>

silylene old · Jan 15, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Because the source seems to be subsurface, is this a nail in the coffin of the photochemical generation hypothesis?    Posted by centsworth_II</DIV> There is no data supporting that the methane is genertaed below the martian surface, at least from the press release.  here is what Mumma said.  Note the word "if".  He is just running on with rampant speculation."If microscopic Martian life is producing the methane, it likely resides far below the surface, where it's still warm enough for liquid water to exist. Liquid water, as well as energy sources and a supply of carbon, are necessary for all known forms of life. "On Earth, microorganisms thrive 2 to 3 kilometers (about 1.2 to 1.9 miles) beneath the Witwatersrand basin of South Africa, where natural radioactivity splits water molecules into molecular hydrogen (H2) and oxygen. The organisms use the hydrogen for energy. It might be possible for similar organisms to survive for billions of years below the permafrost layer on Mars, where water is liquid, radiation supplies energy, and carbon dioxide provides carbon," said Mumma." <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center">- - - - - - - - - - - - - - - - - - - - - - </div><div class="Discussion_UserSignature" align="center">I really, really, really miss the "first unread post" function. </div> </div>

MeteorWayne · Jan 15, 2009

SDC Article:http://www.space.com/scienceastronomy/090115-mars-methane-news.html <div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

...analysis of the Martian atmosphere that raises the possibility of life or geologic activity...

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