I think they need to send people to confirm whether there is life there.
This is one of the most complete and science-based article about the Martian Rovers I ever read. Congratulations Chris G. Really enjoyed reading it.I only question the very last statement: “So if life emerged on Earth in these conditions, why not on Mars as well?”This statement is just a little bit stretched. This is the kernel of the problem, not an answer. We just don't know which is the probability for life to develop and all this emphasis on "organics molecules" (found rather everywhere in the cosmos) should not bias actual knowledge that we just don't know. We really don't know what trigger the development of life. Our knowledge on this matter is nearing zero.Last point, rather than thinking what we could do on Mars with a manned expedition, I wonder just the opposite: what we could do on Mars (and somewhere else) with more money and more frequent and evolved Mars Rovers up there rather than in dubious and scientifically marginal (for the bucks) outposts in LEO orbit.p.s. Please remember this is an opinion based on actual arguments. It's unpopular and can certainly be negated, but I still have the right to tell and discuss it based on actual arguments.
Well it's not as if Mars is going to be short of upcoming rovers. I can think of least four up until the end of the decade; ExoMars, Curiosity MK 2 and rovers from India & China.
I only question the very last statement: “So if life emerged on Earth in these conditions, why not on Mars as well?”This statement is just a little bit stretched. This is the kernel of the problem, not an answer. We just don't know which is the probability for life to develop and all this emphasis on "organics molecules" (found rather everywhere in the cosmos) should not bias actual knowledge that we just don't know. We really don't know what trigger the development of life. Our knowledge on this matter is nearing zero.
I have to disagree. The article is very astute.
Quote from: scienceguy on 12/30/2014 04:24 amI think they need to send people to confirm whether there is life there.I think that can probably confirm that without the intervention of humans directly.
This is one of the most complete and science-based article about the Martian Rovers I ever read. Congratulations Chris G. Really enjoyed reading it.I only question the very last statement: “So if life emerged on Earth in these conditions, why not on Mars as well?”This statement is just a little bit stretched. This is the kernel of the problem, not an answer. We just don't know which is the probability for life to develop and all this emphasis on "organics molecules" (found rather everywhere in the cosmos) should not bias actual knowledge that we just don't know. We really don't know what trigger the development of life. Our knowledge on this matter is nearing zero.
Last point, rather than thinking what we could do on Mars with a manned expedition, I wonder just the opposite: what we could do on Mars (and somewhere else) with more money and more frequent and evolved Mars Rovers up there rather than in dubious and scientifically marginal (for the bucks) outposts in LEO orbit.
Quote from: Star One on 12/30/2014 09:51 amWell it's not as if Mars is going to be short of upcoming rovers. I can think of least four up until the end of the decade; ExoMars, Curiosity MK 2 and rovers from India & China.It's not a problem of quantity (is 4 small or large? Is 6 astronauts on board small or large? Who knows? ) but of budget and sophistication.
If you consider that a Curiosity costed 7 billion USD spread over several years compared to 3/yr for the ISS. And then you consider the science return from both... That's what I liked about Chris's article. It clearly shows the enormous amount of scientific output coming out from two little things lasting a decade almost for free
ADDED: despite that, funding for extended missions since 2015 is not yet guaranteed AFAIK... ridiculous! And even if it will, it's unbelievable this has not been given the highest-level priority.
Quote from: Torbjorn Larsson, OM on 12/31/2014 03:10 amI have to disagree. The article is very astute.Essentially, the feeling is that in the last 3-4 decades we are accumulating a lot of "evidences" about life, as there is a continuous number of outreach articles "ehi, look at this! This means we are closer to finding alien LIFE!!!". But when you look at what they say is just something we already know since long time. Like counting more and more times the same evidence. The fact that organic molecules can be found almost everywhere, for example (on 67P, in the interstellar matter, or quite abundant "sugar" in a planet formation region), is no more a surprise and should be seen like that. Also the methan amount variation found recently look like like this: we found something new. But this too was well known since many years and we have just confirmed it with no further increase of the probability for this to be related to some organic process. Interesting, but not tending - as media put it - any closer to finding life around.
I find quite often that a lot of people miss the importance of this simple statement today: finding conditions for life, doesn't necessarily mean we will find life as the probability for life to develop is essentially unknown, even when you add the information you added. As Dirac put it once, if this probability is - for example - 10^-100/billion year/average planet, we will never find life (probably, unless there are some "transport" from one planet to another, that can be the case of Mars...). And there is no reason to say it is 10^-100 or 10^-10. As simple like that.
Do you realise how limited the science done by Curiosity actually is? For example for mineralogy we have had only four analyses published to date, in over two years. Two of sand, two of rock, of sites sampled two years ago.
Despite the hype Curiosity fell well short of what was predicted before landing.
Quote from: Dalhousie on 12/31/2014 10:39 pmDespite the hype Curiosity fell well short of what was predicted before landing.Your other criticisms are well founded. This isn't.
Curiosity's instrument package was well along before Phoenix's results addressed Viking's questions effectively. It was too far along to allow a complete redesign and requalification, not to mention implicit regulatory issues that would be created by such a late change. It was either fly or not fly. I'm glad they flew and are getting a science product. It is too early to conclude Curiosity's impact on planetary science.
Likewise, it is unmanned or nothing. I prefer unmanned. Ask me again when manned becomes possible.
All in all, funding planetary landing missions are really unpredictable. Too much rides on too little, too few, too infrequent. That is the top issue, and has been before Viking, as far as Mars. Mars is the best case too - the Moon, Venus, rest of planets/moons too (excepting Huygens on Titan) ... haven't got squat in comparison.
Quote from: Dalhousie on 12/31/2014 10:24 pmDo you realise how limited the science done by Curiosity actually is? For example for mineralogy we have had only four analyses published to date, in over two years. Two of sand, two of rock, of sites sampled two years ago.I'm wondering : if you have a human operating the same data acquisition tools that Curiosity was given ( because of obvious payload limitations ) and relaying back data at the same rate, how would you expect to get more science done ? Because that is all that Curiosity does, it acquires data and sends it back to earth where the actual "science" gets done.
If you designed it for more bandwidth/power/payload with more in-situ instruments available etc then it would be sending back a lot more, of course.
EDIT: i dont mean this as a humans vs robots argument actually. I think it is obvious that that if you allocate mass budgets on the scale that is required for human missions, you will get proportionally larger returns too. Apollo went to the moon with 50 tons TLI, if you ever decide to send so much equipment to Mars, prepare to be amazed. Manned or unmanned.
Curiosity is severely mass restricted. This has turned up in two major effects so far.1. The wheels were made too thin and get damaged by sharp rocks. This has required choice of alternate routes.2. The power source is very weak. So the rover moves sloooowly.The delay in reaching further up the mountain is also because Curiosity found something very interesting to study along the way, and has actually already confirmed some of the things it was sent to study.The goal is not to climb the mountain. The goal is to learn.
I'm no fan of Curiosity's cost, or even in general how NASA today runs surface missions. But i don't see how any of the shortcomings or oversights could be fixed by anything but flying more, more frequently, and invest much more in capability enabling technologies.
>>Because hand held instruments equivalent to most of Curiosity's (say a Niton XRF or an ASD spectrometer, which has no counterpart on Curosity) can collect hundreds of readings a dayThat is useless if you don't have power budget to actually run the instruments the or bandwidth and power budget to actually send the data back. An astronaut similarly handicapped wont be able to do more either.
If you want more capable science missions, invest much much more in enabling technology : laser communications and full-coverage relays, things like ASRG or the thermoacoustic alternatives, enabling precision landing technologies like DSAC and ALHAT so on surface mission staging and capability build-up becomes possible, more flexible robotics with changeable effectors ala DEXTRE. And many more.And at the end of the day, you are always mass limited no matter what you do, so to get more, fly more.
As for 50-ton TLI missions - the only thing i saw was the reference to 2024+ "one shot MSR" launched by SLS that was supposedly put forth by MPPG but is incredibly light on the specifics and looks more like cocktail napkin. I dont think that is a good way to use funds or payload mass - too much riding on one rocket failure.
Really good article Chris. Really good. One of the best I have ever seen on the rover. Thank you.I do have a question however which wraps directly into some of the statements wrt "life". Can anyone actually define what life is and is not? What is the chemical difference between a live animal and a dead one? Can we measure that? Sure we know it when we see it (on earth) but can you measure it? What is the chemical composition of "life"? How do we test for it? AFAICT all we can really do is to test the environment for chemicals that usually accompany *earth-based* life - as we know it. But as for testing anything and actually identifying "life", I do not believe that is possible. Nobody today can actually define what life is, let alone test for it. We can test for and identify the presence of every element in the periodic table, but "life" is not on that table. It's not an element. How do we test for it?
Crewed missions have power budgets of the order of 200 kWhs per sol, so the power demands of hand held instruments are trivial... An off the shelf hand-held spectrometer uses about 8 Whs and and can run for 4 hours on batteries, enough for thousands of readings
None of which will come near to what a scientist will get in the field. None of which get round the problem of latency.
DEXTRE masses 1.56 tonnes and uses an average of 1.4 kW, it requires direct teleoperation and has so far failed to live up to expectations (it was supposed to replace up to 50% of EVAs). Hardly an alternative.
Quote from: Space Ghost 1962 on 12/31/2014 11:28 pmQuote from: Dalhousie on 12/31/2014 10:39 pmDespite the hype Curiosity fell well short of what was predicted before landing.Your other criticisms are well founded. This isn't.I suggest you read the pre launch and pre landing predictions on where Curiosity would have been by now. In 2010 Curosity team members were making presentations saying that the rover would have travelled more than 30 km and climbed more than 800 m by now.The pre-landing press kit had scaled this back somewhat, but was still predicting that Curiosity would be in the foothills by now.
QuoteLikewise, it is unmanned or nothing. I prefer unmanned. Ask me again when manned becomes possible. At present it is indeed unmanned or nothing. Half full is better than none at all. Have I said otherwise?
However manned missions to Mars are technically feasible now.
...although the Moon has been doing quite well in the past ten years or so!
QuoteNone of which will come near to what a scientist will get in the field. None of which get round the problem of latency. I'm not entirely convinced that latency is that big of an obstacle for science - which gets done with MATLAB in months after the data collection anyway. Data acquisition lag of a few minutes does not damper paper publishing rate by a lot.I understand everyone wants more data and faster - the way to get more data is build a more powerful machine, and while you are at it don't make its wheels out of beer cans. If you want more traverse to get more data from different locations, then actually invest in mobility - there is no fundamental technical reason why you couldn't drive across Mars at miles per hour, but you do need to make the technology investments.
If you want high-powered instruments on Mars, then send high-powered (and less-flimsy) instruments to Mars. There is no need to send people to operate them - the cost would be many orders of magnitude greater because the people would probably want to come back, require lots of Oxygen and Food and DVDs of "Three's Company" while they are there, etc etc.
We know what a crewed mission is likely to achieve, there have been innumerable studies. Here is the target to aim for.1000 km of traverse1000 kg of surface science payload400 kg returned samples10 m drill depths
Quote from: Dalhousie on 01/01/2015 05:00 amCrewed missions have power budgets of the order of 200 kWhs per sol, so the power demands of hand held instruments are trivial... An off the shelf hand-held spectrometer uses about 8 Whs and and can run for 4 hours on batteries, enough for thousands of readings Uh .. so the logical argument here is for more power on surface. I.e. basically what every mission planner always wants anyway .. There are only so few ways to have more power ( humans and horses dont help with that ) - more solar either from ground or orbit, or more nuclear with better efficiency.Exactly what ThereIWas3 said here too, if you want more power, send more power.
I understand everyone wants more data and faster - the way to get more data is build a more powerful machine, and while you are at it don't make its wheels out of beer cans. If you want more traverse to get more data from different locations, then actually invest in mobility - there is no fundamental technical reason why you couldn't drive across Mars at miles per hour, but you do need to make the technology investments.
Quote DEXTRE masses 1.56 tonnes and uses an average of 1.4 kW, it requires direct teleoperation and has so far failed to live up to expectations (it was supposed to replace up to 50% of EVAs). Hardly an alternative.I think you misread - i'm not proposing sending DEXTRE to mars, robotic arms can be built as big as small as needed - see Curiosity or Yutu. What i'm saying is designing for more dexterous and modular robotics opens up new ways of capability expansion. By sending more tools to DEXTRE arsenal you can make it do things that it was not originally planned to do.But that presumes pinpoint landing ability - again a technical investment milestone, nothing to do with manned missions.
So by "predictions" you mean "rate of progression of travel". Took it to mean "science predictions".These were absurdly high to begin with, to justify the "nuclear" power instead of solar. At one point banking much on driving through the night. How do you do science while driving through the night? Personally expected a fractional improvement over Opportunity/Spirit, while also a decrease due to a more elaborate science package requiring more "non driving time". There are political aspects to missions that intrude on reality. I would class this under that.
Quote from: Dalhousie on 01/01/2015 12:01 amHowever manned missions to Mars are technically feasible now. "Theoretically" I'll buy. "Technically" no way - too much in the way of undemonstrated/unproven capability. Worse - no political will to fund - a necessary part of "technically" in my book.
Quote from: Dalhousie on 01/01/2015 12:01 am...although the Moon has been doing quite well in the past ten years or so!Hardly - cheap missions. No American lander/rover. Chinese with Yutu rover best example. "Precision bombing" didn't yield as much science product as humor...
Quote from: Dalhousie on 01/01/2015 08:06 pmWe know what a crewed mission is likely to achieve, there have been innumerable studies. Here is the target to aim for.1000 km of traverse1000 kg of surface science payload400 kg returned samples10 m drill depthsWith an IMLEO of 500 mT ?
I don't think it's reasonable to judge Curiosity's "progress" simply by how far it has traveled. After the initial analysis of findings at Yellowknife Bay, the science team announced that they had found clays and many indicators of an ancient habitable environment there, so the primary science mission of Curiosity had been accomplished, and without even requiring her to ascend 800 meters up the side of Mt. Sharp. There was even talk about reworking the driving plan and staying primarily in the Yellowknife complex for the remainder of the mission.
Also, every pre-planned route I've ever seen has carefully omitted a lot of details on exactly when the rover would arrive at any given point, with footnoting galore warning that any major finds along the way might delay the overall traverse progress. When you don't know what you're going to find over the next rise, it's hard to be real accurate when it comes to predicting where you'll be 50 or 100 sols from now.
Besides, from the press releases I've read, they're considering the Pahrump Hills, where they are spending a lot of time right now, as being in the foothills of Mt. Sharp. So, technically, they have reached the foothills by now.
Quote from: Space Ghost 1962 on 01/01/2015 07:06 pmSo by "predictions" you mean "rate of progression of travel". Took it to mean "science predictions".These were absurdly high to begin with, to justify the "nuclear" power instead of solar. At one point banking much on driving through the night. How do you do science while driving through the night? Personally expected a fractional improvement over Opportunity/Spirit, while also a decrease due to a more elaborate science package requiring more "non driving time". There are political aspects to missions that intrude on reality. I would class this under that. They were absurdly high in retrospect, but they were widely believed. These illustrate much of the absurd expectations people have of robotic surface exploration. Political aspects should not lead to people lying. I would go to self deception or simply being wrong. And it should be a lesson for the future. Robotic rover missions, especially future ones, will be oversold. It’s happened with the 2020 rover already and continues to happen with Curiosity for the extended mission
QuoteQuote from: Dalhousie on 01/01/2015 12:01 am...although the Moon has been doing quite well in the past ten years or so!Hardly - cheap missions. No American lander/rover. Chinese with Yutu rover best example. "Precision bombing" didn't yield as much science product as humor... I don’t care whether a mission is American or not. The mission may have been cheap, but have been enormously successful and transformed many aspects of lunar science.
The “Precision bombing" didn't yield as much science product as humor... completely missed me, I’m sorry.
Ames Research Center is go for the first precision bombing run on the moon.
Quote from: ThereIWas3 on 01/01/2015 05:18 pmIf you want high-powered instruments on Mars, then send high-powered (and less-flimsy) instruments to Mars. There is no need to send people to operate them - the cost would be many orders of magnitude greater because the people would probably want to come back, require lots of Oxygen and Food and DVDs of "Three's Company" while they are there, etc etc.No way is it many orders of magnitude - once you add in the greatly increased power budget and thus greatly increased mass... the far less capable Curiosity is already like $2.5 billion and I don't think a manned mission would cost $250 billion if done sensibly. (Possibly quite a lot less.)
As I keep asking, come up with numbers that show what is required to provide equivalent science return unmanned to what a crewed mission can do. Numbers, please, not invocation of fantasy robots.
Quote from: Dalhousie on 01/01/2015 09:18 pmAs I keep asking, come up with numbers that show what is required to provide equivalent science return unmanned to what a crewed mission can do. Numbers, please, not invocation of fantasy robots.Fantasy robots vs fantasy ECLSS with fantasy rockets with fantasy SEPs with fantasy MAVs and ERVs and NTRs and cryo prop management and nuclear surface reactors and a looot of other pixie dust. Its all basically a good hard sci-fi story.Because its an interesting thought exercise, at some point i'll probably write up my ideas what a technology capability driven Mars exploration program would look like but you will be disappointed - couple of first launch windows would go to 100% enabling technology development with absolutely minimal science returns.
Quote from: savuporo on 01/02/2015 03:37 am Quote from: Dalhousie on 01/01/2015 09:18 pmAs I keep asking, come up with numbers that show what is required to provide equivalent science return unmanned to what a crewed mission can do. Numbers, please, not invocation of fantasy robots.Fantasy robots vs fantasy ECLSS with fantasy rockets with fantasy SEPs with fantasy MAVs and ERVs and NTRs and cryo prop management and nuclear surface reactors and a looot of other pixie dust. Its all basically a good hard sci-fi story.Because its an interesting thought exercise, at some point i'll probably write up my ideas what a technology capability driven Mars exploration program would look like but you will be disappointed - couple of first launch windows would go to 100% enabling technology development with absolutely minimal science returns.If you are not prepared to do the work then I suggest you stop arguing a position for which you have neither the evidence or the wiliness to defend . I suggest you defer to those who have the numbers and the experience from both the human and the robotic end. If you are not prepared to do the numbers then I suggest as a minimum you come up with three Mars or lunar scientists who think that crewed missions are not desirable or needed. With either links or references
So according to this, a spacesuited human is 25x more effective than a robot controlled from Earth. Of course when making a comparison to manned Mars exploration one has to take into account that robots can be operated for several years and multiple robotic missions can target different sites of interest on the planet.
If you spent half of the budget for a manned mission to mars on unmanned missions, I believe you would got many times more science for the money. Anybody can hand wave cheaper manned missions or more capable robots. The ISS cost what 100B dollars? I don't believe a mars mission could be done for five times that, not by government contractors anyway.
How long would this manned mission dwell on the surface, a few months at most?
Would science even allow a manned mission before we know what damage we would cause by contaminating the planet with humans and their byproducts?
Let's get back on to the subject of this thread, which is the article, which isn't a honey pot for the anti-HSF gang.
Well over 600 samples have been analyzed with the ChemCam; once a mineral has been identified the laser is apparently pretty accurate in identifying it without full analysis.
Signal latency is indeed a major limitation in both rover movement and sample selection. One way to overcome this obstacle without humans at Mars is with improved artificial intelligence to allow autonomous rover movement and sample selection. Curiosity's computational power, although impressive for a radiation-hardened spacecraft (400MIPS, 256 kB of EEPROM, 256 MB of DRAM, and 2 GB of flash memory), is minimal compared to a modern cell phone, let alone typical autonomous vehicles like the Google car, but NASA is the only government agency that operates robots at distances too great for teleoperation, and NASA should be leading the way in the development of AI for exploration. We will need it, unless we plan to send humans to Europa, Titan and maybe Pluto in the near future. If we achieve it, the productivity of all rovers on any celestial body will be greatly improved.
Quote from: Torbjorn Larsson, OM on 12/31/2014 03:10 amI have to disagree. The article is very astute.Interesting comment, thanks, although I am not necessarily convinced. The fact that life emerged very early is a good indicator, but statistically speaking doesn't say very much. Can you please write some references regarding what you says?
I remember a paper some years ago (cannot find it anymore but I discussed about it very much) talking about the fact that DNA/RNA could be the only chemical mechanism available to guarantee certain characteristics of life. This is important because it means we could at least "recognize" alien life and apply standard tests to verify its existence.
Typically you don't use definitions to recognize life anymore than you do to recognize rocks or species. You have to differentiate, as Noffke does for fossils.There are more or less unique properties of life though:- Species are products of the life process (evolution; Darwin's definition). Therefore you can test populations (but not individuals) for that.- Organisms are persistent. (Schroedinger's definition; Pross's take on the topological stability that exponential replication confer.) You can test for that.- Organisms are irreversible. (Haldane's definition; Pross's take on the thermodynamics of replication.) You can test for that, but there are confusions.- Organisms are based on a genetic ancestry of RNA (most likely; England's research on the thermodynamics of replication). As I understand it, the variants of nucleotides are strictly set by RNA replication and catalysis to be 4 and those 4 out of 8 possible. [There is a good Quora response to that effect.] We happen to use the 4 that are more or less most easy to produce chemically I think.- Cells vibrate. (The new nano-beam test for collections of live cells. Bacteria use pumps in/out and flagella (some); archaea and eukaryotes use internal actins and tubulins to reconfigure, move (some species), divide, ... Of course some archaea has archella and some eukaryotes cilia to move.) Again: tests and confusions.
Quote from: Torbjorn Larsson, OM on 01/08/2015 11:45 amTypically you don't use definitions to recognize life anymore than you do to recognize rocks or species. You have to differentiate, as Noffke does for fossils.There are more or less unique properties of life though:- Species are products of the life process (evolution; Darwin's definition). Therefore you can test populations (but not individuals) for that.- Organisms are persistent. (Schroedinger's definition; Pross's take on the topological stability that exponential replication confer.) You can test for that.- Organisms are irreversible. (Haldane's definition; Pross's take on the thermodynamics of replication.) You can test for that, but there are confusions.- Organisms are based on a genetic ancestry of RNA (most likely; England's research on the thermodynamics of replication). As I understand it, the variants of nucleotides are strictly set by RNA replication and catalysis to be 4 and those 4 out of 8 possible. [There is a good Quora response to that effect.] We happen to use the 4 that are more or less most easy to produce chemically I think.- Cells vibrate. (The new nano-beam test for collections of live cells. Bacteria use pumps in/out and flagella (some); archaea and eukaryotes use internal actins and tubulins to reconfigure, move (some species), divide, ... Of course some archaea has archella and some eukaryotes cilia to move.) Again: tests and confusions.Spiegel & al. 2012 is a very interesting paper indeed. I was thinking to try something like that but had not enough understanding of the issue (and time) for that. Still reading... Those above are unique properties of life on Earth. But what let you assume this are also necessary to alien life? You write that RNA is "most likely" in particular. On what you base that? Any reference?
Curiosity chief scientist responds to Noffke paper.http://www.space.com/28218-mars-rover-curiosity-signs-life.htmlHe could not really say anything else.
England has a good paper on why RNA is uniquely suited as the first catalytic self-replicator.
Quote from: Dalhousie on 01/09/2015 11:14 pmCuriosity chief scientist responds to Noffke paper.http://www.space.com/28218-mars-rover-curiosity-signs-life.htmlHe could not really say anything else.Do you mean in the sense that he had to say that because they decided not too investigate the feature?
Quote from: Star One on 01/10/2015 08:43 amQuote from: Dalhousie on 01/09/2015 11:14 pmCuriosity chief scientist responds to Noffke paper.http://www.space.com/28218-mars-rover-curiosity-signs-life.htmlHe could not really say anything else.Do you mean in the sense that he had to say that because they decided not too investigate the feature?Yes.
Quote from: Dalhousie on 01/10/2015 09:11 pmQuote from: Star One on 01/10/2015 08:43 amQuote from: Dalhousie on 01/09/2015 11:14 pmCuriosity chief scientist responds to Noffke paper.http://www.space.com/28218-mars-rover-curiosity-signs-life.htmlHe could not really say anything else.Do you mean in the sense that he had to say that because they decided not too investigate the feature?Yes.I've seen some criticism online in relation to things like this that the Curiosity science team are too conservative in the targets they choose to investigate. I'm not sure myself whether that's fair or not as looking for life directly isn't its primary mission.
I don't think it is entirely fair either, given the huge issues associated with using the drill.
Quote from: Dalhousie on 01/11/2015 09:31 pmI don't think it is entirely fair either, given the huge issues associated with using the drill.What is the current story with that anyway? I can't remember what specifically the issue was - something about a short circuit risk?Do we know of any plan for dealing with it beyond using it only for very valuable targets?
I think the problem is built in, AFAIK the only solutions are to use it very sparely for the highest value targets and avoid using it in the purcussive mode. Which is a shame really, because the onboad labs have got the capacity to do scores of samples.The announced plan is to collect somewhere between four and eight more samples in the next 19 months (compared to five in the last 29. At current rate of progress I suspect four is the best that can be hoped.
Quote from: Dalhousie on 01/12/2015 09:21 pmI think the problem is built in, AFAIK the only solutions are to use it very sparely for the highest value targets and avoid using it in the purcussive mode. Which is a shame really, because the onboad labs have got the capacity to do scores of samples.The announced plan is to collect somewhere between four and eight more samples in the next 19 months (compared to five in the last 29. At current rate of progress I suspect four is the best that can be hoped.So... what happens when the fault does strike? Is it just the drill that's busted, or the whole vehicle?
Spiegel & al. 2012 is a very interesting paper indeed. I was thinking to try something like that but had not enough understanding of the issue (and time) for that. Still reading...
Those above are unique properties of life on Earth. But what let you assume this are also necessary to alien life? You write that RNA is "most likely" in particular. On what you base that? Any reference?
Good question what is it says that RNA is always the preferred option.
Quote from: Torbjorn Larsson, OM on 01/08/2015 11:16 amEngland has a good paper on why RNA is uniquely suited as the first catalytic self-replicator.I cannot locate this. Link please?
I would add to Anderson's writ that Vasavada rejects Noffke's claim that there are no potential confusions (false positives) at her state of checking off on her MISS tests list, on Earth. (She do want to make a complementary microanalysis and a search for potential false positives, to make sure.) Either Vasavada makes a blanket claim that Noffke is wrong, or he has observations that would teach MISS experts something new.In either case it would be useful, not least for strategies on rover science, if Vasavada wrote a counter-article that lays out his evidence for errors or Mars's unique MISS-like geological processes.Can Curiosity's team really leave this behind as "a causal dismissal", especially since the 2020 rover isn't finalized? Any thoughts?
This paper now seems to be slowly picking up some more widespread coverage.http://www.theage.com.au/technology/sci-tech/astronomy/photos-show-possible-signs-of-ancient-microbial-life-on-mars-20150112-12mt27.htmlhttp://m.huffpost.com/us/entry/6425392http://io9.com/this-curiosity-image-suggests-microbial-life-once-exist-1677739858
Quote from: Star One on 01/13/2015 10:07 pmThis paper now seems to be slowly picking up some more widespread coverage.http://www.theage.com.au/technology/sci-tech/astronomy/photos-show-possible-signs-of-ancient-microbial-life-on-mars-20150112-12mt27.htmlhttp://m.huffpost.com/us/entry/6425392http://io9.com/this-curiosity-image-suggests-microbial-life-once-exist-1677739858Uh oh... almost time for misinformed reporters to take it as an absolute fact that these structures were formed by life.
Yeah... good point.I do hope they find similar features in the future, and take the time to investigate them closely as a result of this paper. Maybe media attention will make investigation more likely.
Quote from: Torbjorn Larsson, OM on 01/13/2015 06:04 pmI would add to Anderson's writ that Vasavada rejects Noffke's claim that there are no potential confusions (false positives) at her state of checking off on her MISS tests list, on Earth. (She do want to make a complementary microanalysis and a search for potential false positives, to make sure.) Either Vasavada makes a blanket claim that Noffke is wrong, or he has observations that would teach MISS experts something new.In either case it would be useful, not least for strategies on rover science, if Vasavada wrote a counter-article that lays out his evidence for errors or Mars's unique MISS-like geological processes.Can Curiosity's team really leave this behind as "a causal dismissal", especially since the 2020 rover isn't finalized? Any thoughts?I don't think Vasavada has any personal competence to assess Noffke's paper. He is not a geologist, let alone a palaentologist, has not done any field work on any planet, he's a physicist and a modeller.Of course here I assume he is speaking for the team. Right or wrong the team, including people who were competent to make the call decided that these features were not worth a closer look. It's too far away in time and space to go back and check again.All they can do is perhaps be a bit more alert to the possibility, should they see similar features, and perhaps look more closely.
I don't see any impact for the 2020 mission myself, beyond a pointer to the possibility of returning microbial textures.
Chris McKay (who is on the Curiosity team) and Penny Boston (who isn't), both leading astrobiologists commented favourably on the paper. http://www.astrobio.net/news-exclusive/potential-signs-ancient-life-mars-rover-photos/
Why doesn't NASA send an actual life detection mission?
Quote from: Vultur on 01/17/2015 03:08 amWhy doesn't NASA send an actual life detection mission?Because there's nothing there.Everyone knows there's nothing there. That's why the goal has shifted to "evidence of fossil life" and other nonsense.
Quote from: QuantumG on 01/17/2015 03:44 amQuote from: Vultur on 01/17/2015 03:08 amWhy doesn't NASA send an actual life detection mission?Because there's nothing there.Everyone knows there's nothing there. That's why the goal has shifted to "evidence of fossil life" and other nonsense.Um... based on what? Endoliths could probably survive on current Mars just fine, if there's even tiny traces of water subsurface. Their requirements are extremely small (and being subsurface, the UV won't bother them).I see absolutely no reason to think that current life on Mars is unlikely.EDIT: And anyway, NASA hasn't even sent a lander/rover that could look for evidence of fossil life!
the bigger problem is that we STILL don't have a definitive chemical signature that we can point to and say "look! here is life!" there is no magical "life detection" box that we could send to Mars yet. yes, the technology we've got today is much better than it was for Viking, but there is still no consensus for what needs to be looked for when we are searching for life. the proposed instruments that we'd use to search for life have lots of limitations.
and i'd argue that NASA has sent both landers and rovers that can look for evidence of fossil life, or even current life, anything that is within their capabilities to see, they could find. Curiosity's MAHLI is capable of taking images 13.9 microns per pixel, for example, and there are lots of life-forms here on Earth that are larger than that.
QuantumG may have stretched a bit the conclusions, but the number of (informed) scientists thinking there is life on Mars is marginal shrinking (when one exclude those with a conflict of interest. )
Quote from: whitelancer64 on 01/18/2015 07:34 pmthe bigger problem is that we STILL don't have a definitive chemical signature that we can point to and say "look! here is life!" there is no magical "life detection" box that we could send to Mars yet. yes, the technology we've got today is much better than it was for Viking, but there is still no consensus for what needs to be looked for when we are searching for life. the proposed instruments that we'd use to search for life have lots of limitations. Sure, it's not an easy problem, but that's no reason not to try. Viking tried with what was available back then; the field has advanced to the point that I think it's time to try again.If Mars life is nucleic acid based (which seems not unlikely) it should be (comparatively) easy to unambiguously identify. If not, the best route IMO would be to look for really complex organic molecules with structures that suggest "biomolecules" (with a non-heating-based method like a Raman spectrometer, not SAM - which I think ExoMars and Mars 2020 are supposed to have).Quoteand i'd argue that NASA has sent both landers and rovers that can look for evidence of fossil life, or even current life, anything that is within their capabilities to see, they could find. Curiosity's MAHLI is capable of taking images 13.9 microns per pixel, for example, and there are lots of life-forms here on Earth that are larger than that.Sure, but the life wouldn't be on the surface due to UV - it would be subsurface, maybe shallow, but not exposed. You have to scoop and drill.Microfossils or stromatolite-type things might be found, but identifying them unambiguously enough to convince the scientific community from a MAHLI image alone seems unlikely.
Quote from: Vultur on 01/18/2015 07:16 pmQuote from: QuantumG on 01/17/2015 03:44 amQuote from: Vultur on 01/17/2015 03:08 amWhy doesn't NASA send an actual life detection mission?Because there's nothing there.Everyone knows there's nothing there. That's why the goal has shifted to "evidence of fossil life" and other nonsense.Um... based on what? Endoliths could probably survive on current Mars just fine, if there's even tiny traces of water subsurface. Their requirements are extremely small (and being subsurface, the UV won't bother them).I see absolutely no reason to think that current life on Mars is unlikely.EDIT: And anyway, NASA hasn't even sent a lander/rover that could look for evidence of fossil life!QuantumG may have stretched a bit the conclusions, but the number of (informed) scientists thinking there is life on Mars is marginal shrinking (when one exclude those with a conflict of interest. )The point is that repeating ad nauseam that there MAY be life on Mars doesn't make life more likely.
Quote from: pagheca on 01/18/2015 07:38 pmQuote from: Vultur on 01/18/2015 07:16 pmQuote from: QuantumG on 01/17/2015 03:44 amQuote from: Vultur on 01/17/2015 03:08 amWhy doesn't NASA send an actual life detection mission?Because there's nothing there.Everyone knows there's nothing there. That's why the goal has shifted to "evidence of fossil life" and other nonsense.Um... based on what? Endoliths could probably survive on current Mars just fine, if there's even tiny traces of water subsurface. Their requirements are extremely small (and being subsurface, the UV won't bother them).I see absolutely no reason to think that current life on Mars is unlikely.EDIT: And anyway, NASA hasn't even sent a lander/rover that could look for evidence of fossil life!QuantumG may have stretched a bit the conclusions, but the number of (informed) scientists thinking there is life on Mars is marginal shrinking (when one exclude those with a conflict of interest. )The point is that repeating ad nauseam that there MAY be life on Mars doesn't make life more likely.I don't think the number scientists that think there might be life on Mars is shrinking. If anything its increasing.
Precisely that was my reading of the situation as well. Not sure where the OP got the idea from that it was shrinking number and would in fact ask them to present some kind of evidence to back up that statement so counter to the actual situation is it.
An informal poll of 250 scientists attending the Mars Express Science Conference at Noordwijk in the Netherlands last month revealed how high their hopes have climbed. About three-quarters think life could have existed on Mars in the past, and a quarter think life could be there today.
Quote from: Star One on 01/19/2015 08:12 amPrecisely that was my reading of the situation as well. Not sure where the OP got the idea from that it was shrinking number and would in fact ask them to present some kind of evidence to back up that statement so counter to the actual situation is it.Just an impression, I will candidly admit that. I spoken with several colleagues about that in some occasions and I got the impression that a lot of professional astronomers, if obliged to bet, would now say there is no life at present on Mars (maybe in the past) after some past bandwagon effect.This is not enough to say "there is no life at present on Mars", neither to conclude the number of scientists believing there is is shrinking, but I got the impression that the general public is much more positive about the idea (again: life on Mars TODAY) than informed scientists.Now, by looking to the internet to investigate more about this quite interesting issue (what planetary scientists think about the chance of life on Mars), I found a 2005 Nature paper saying that QuoteAn informal poll of 250 scientists attending the Mars Express Science Conference at Noordwijk in the Netherlands last month revealed how high their hopes have climbed. About three-quarters think life could have existed on Mars in the past, and a quarter think life could be there today.So, apparently at the time - almost 10 years ago, therefore before most of the rovers works came out - the number was rather increasing. It would be very interesting to check the number now at a similar intl. conference. However, this was people attending a "Mars Express" conference, so, highly tied to this hope. STANDARD DISCLAIMER: just to clarify, I'm not interested in defending one or the other position, and I'm ready - as always - to change opinion or even to renounce to an opinion. At the end of the day, what scientists believe is less relevant than what they know, but up to when the limited, available funding must be directed toward one or other competitive targets. My impression is, again, that this "life on Mars" thing has been quite pimped up in the past to obtain more funding (example: don't be a Venus planetologist today, as your chances to get funded are quite dimmed) and because was obviously nice meat for the general media. Every single result was immediately accompanied with the claim that this show that look! There MAY BE life on Mars (look for example at that methane fluctuation issue), stretching evidences and transforming an hypothesis almost in a certainty by talking about that over and over. Please read carefully what I said. I'm not embracing one or another position on this quest at this point, but I rather think it's very difficult to be unbiased after so much continuous talking about life on Mars. I always feel like whatever I think it's because I'm biased.
Which is not the impression of what your position was in your OP.
Quote from: Star One on 01/19/2015 08:12 amPrecisely that was my reading of the situation as well. Not sure where the OP got the idea from that it was shrinking number and would in fact ask them to present some kind of evidence to back up that statement so counter to the actual situation is it.Just an impression, I will candidly admit that. I spoken with several colleagues about that in some occasions and I got the impression that a lot of professional astronomers, if obliged to bet, would now say there is no life at present on Mars (maybe in the past) after some past bandwagon effect.
Quote from: pagheca on 01/19/2015 09:07 amQuote from: Star One on 01/19/2015 08:12 amPrecisely that was my reading of the situation as well. Not sure where the OP got the idea from that it was shrinking number and would in fact ask them to present some kind of evidence to back up that statement so counter to the actual situation is it.Just an impression, I will candidly admit that. I spoken with several colleagues about that in some occasions and I got the impression that a lot of professional astronomers, if obliged to bet, would now say there is no life at present on Mars (maybe in the past) after some past bandwagon effect.There is the problem perhaps. The issue is no longer one being explored by astronomers but by geobiologists, geochemists, microbiologists, palaeontologists, biochemists.Singular experiences can be misleading as others have said, but currently I am in the field in NZ with a half a dozen astrobiologists, all quite convinced of the possibility of life on Mars either now or in the past. Most are young. So from where I stand it's not a shrinking field.
Quote from: Dalhousie on 01/13/2015 09:01 pmI don't see any impact for the 2020 mission myself, beyond a pointer to the possibility of returning microbial textures.It could, probably should, be used to weight similar lakes but especially playa environments into the landing ellipse (the survey area in that case). Else it will be more a geological than a biological mission again. (It need to be both for biology's sake, but one can always argue the best balance.)I assume it is too late to modify the instrument set (to go through Noffke's microanalysis requirements in situ if possible). Especially since it would be speculative based on tentative findings. That would be more an argument against the pushing of planetary missions against each other so that one can't inform the construction of the next.
That's interesting to hear & kind of reassuring speaking personally that I hadn't completely misread the situation. The fact we keep finding life on Earth in the most unexpected places even if not directly applicable to the Martian situation must still raises hopes a little.
Singular experiences can be misleading as others have said, but currently I am in the field in NZ with a half a dozen astrobiologists, all quite convinced of the possibility of life on Mars either now or in the past. Most are young. So from where I stand it's not a shrinking field.
Quote from: Dalhousie on 01/19/2015 05:19 pmSingular experiences can be misleading as others have said, but currently I am in the field in NZ with a half a dozen astrobiologists, all quite convinced of the possibility of life on Mars either now or in the past. Most are young. So from where I stand it's not a shrinking field.No problems. I try to feel no attachments to (my) opinions, and I'm very suspicious about "hard" opinions as in the hedgehog and the fox. Actually I found very interesting what you said and would be interested in knowing why they think that, although I think that astronomers have something to say because the attention is now pointed to exoplanets, not only on Mars. Also, note I never said "there is no life on Mars" (others use this kind of hard statement, not me). I just tried to clarify what QuantumG was saying based on my experience.p.s. And I have a very deep attachment to NZ too as I spent a lot of time in the South Island (and got married in Christchurch...). Please let me know where you are. Just curious...
...positions that say "everyone knows there is no life" are really annoying, they are not based on facts and are poor science.
As far as I'm concerned, anyone who takes "what everyone knows" as a set of basic tenets when embarking on scientific research should be dis-embarked. Though those are not as bad as people who undertake research to "prove what I already know is the truth."
Don't take this personally, but just as a general rules: cognitive biases are everywhere. Not only where you (or me) think they are.
Quote from: pagheca on 01/20/2015 02:30 pmDon't take this personally, but just as a general rules: cognitive biases are everywhere. Not only where you (or me) think they are.Oh, not taken personally at all. And I agree with you that, sometimes, radical new theories aren't always the correct new theories. In some cases, it is very true that extraordinary proof is required to support extraordinary theories.And, to toss out the devil's advocacy on it, warm & wet early Mars is becoming "what everyone knows," and to an extent those who theorize that much of the surface evidence we see for ancient liquid water could actually be caused by ejecta and pyroclastic flow events are those who are contradicting the popular wisdom. So, indeed, the biases shift over time (sometimes over very short periods of time), and it is useful to have an aggregate view that cancels out the various biases.I think we can all agree that there is a difference between caution and pig-headedness, though...
Quote from: the_other_Doug on 01/20/2015 04:38 amAs far as I'm concerned, anyone who takes "what everyone knows" as a set of basic tenets when embarking on scientific research should be dis-embarked. Though those are not as bad as people who undertake research to "prove what I already know is the truth."I agree with you but:(1) there is a rationale behind trusting a poll of experts more than a single one or personal judgment, when evidences are not enough: as you probably know it has been demonstrated by a large number of studies that predictions by groups of experts are usually more accurate than anything else. At the conditions those opinions are independent and not the result of bandwagon effect. This works in politics as well as in a SpaceX yearly number of flights poll, for example, that is a good reason to take them quite seriously (and they usually are a quite good predictor...).(2) there is also a complementary mistake: extrapolate from the fact that a certain number of theories were contradicted by new evidences that also the next one will be contradicted soon or later.At the end of the day we all tend to underevaluate the importance of anything that is in contradiction with our current sense of "truth". We should fight this bias and look at evidences, rather than trying to find generic rules to demonstrate this or that. In this case, it is true that Mars maybe (or may have been) a more benign environment to the development of life. However, is also true that there are no indisputable evidences for life on Mars to date, despite our knowledge of the planet increased by several orders of magnitude in the last decade. Don't take this personally, but just as a general rules: cognitive biases are everywhere. Not only where you (or me) think they are.
Quote from: pagheca on 01/20/2015 02:30 pmQuote from: the_other_Doug on 01/20/2015 04:38 amAs far as I'm concerned, anyone who takes "what everyone knows" as a set of basic tenets when embarking on scientific research should be dis-embarked. Though those are not as bad as people who undertake research to "prove what I already know is the truth."I agree with you but:(1) there is a rationale behind trusting a poll of experts more than a single one or personal judgment, when evidences are not enough: as you probably know it has been demonstrated by a large number of studies that predictions by groups of experts are usually more accurate than anything else. At the conditions those opinions are independent and not the result of bandwagon effect. This works in politics as well as in a SpaceX yearly number of flights poll, for example, that is a good reason to take them quite seriously (and they usually are a quite good predictor...).(2) there is also a complementary mistake: extrapolate from the fact that a certain number of theories were contradicted by new evidences that also the next one will be contradicted soon or later.At the end of the day we all tend to underevaluate the importance of anything that is in contradiction with our current sense of "truth". We should fight this bias and look at evidences, rather than trying to find generic rules to demonstrate this or that. In this case, it is true that Mars maybe (or may have been) a more benign environment to the development of life. However, is also true that there are no indisputable evidences for life on Mars to date, despite our knowledge of the planet increased by several orders of magnitude in the last decade. Don't take this personally, but just as a general rules: cognitive biases are everywhere. Not only where you (or me) think they are.There's an old saying, "If it looks like a Duck, smells like a Duck and acts like a Duck, it's probably a Duck... Except when it's not.In other words, while all evidence is pointing towards there being life on Mars, we've been fooled too many times by things that made us THINK we'd found life, but in fact, turned out either as a false positive or inconclusive. So, my guess is, that unless we see something squirming under a microscope, eating and exhaling, no one is going to declare that there is life on Mars. Is it probable that there WAS life on Mars? It certainly looks like there may have been. Is there currently life on Mars now? It's pretty certain that there is no life living on the planetary surface of Mars due to the extremely harsh environmental conditions. Could it survive just below the surface, beneith the dust layer? It's quite possible.but no one is going to stretch their neck out across the chopping block without being darned certain that they've found life. (With our luck, they'll find something, think it's life, and it will turn out to be some sort of microor nanotech robotics from some alien star system and it's a million or more years old).
Those kinds of logic traps are only of interest to philosophers.We've known for decades that there's essentially no life on the surface of Mars. There could be life teaming under the surface, we haven't looked, but the surface is obviously dead.It's kinda like how everyone has accepted there's no liquid water on Mars (and very much related). The only exception we know about is brines so concentrated that they essentially don't count.Why should we care about technicalities?
Finding life on Mars doesn't imply an independent origin.