Author Topic: FEATURE: Curiosity confirms organics on Mars; Opportunity’s 10 year anniversary  (Read 37137 times)


Offline Rocket Science

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Wonderful article Chris G. :) What a fantastic little machine that continues to amaze... The teams should proud of their accomplishment!
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Offline eric_astro

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Great article! It's hard to keep up with, and to filter for, the most important  news on the lander missions. Still, NASA's, JPL's, and the university run sites have lots of content, and are of high quality.

I'm not an engineer, but the shorthand references by posters in some threads, to Mars' atmosphere as a vacuum, seem slightly exaggerated! Seems like the mean path length between molecule collisions is closer to the Earth's rather than interplanetary space (see below image from NSF article).


Offline go4mars

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Excellent Article! ;D
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Offline Bubbinski

Superb article, many thanks Chris G!  Excellent overview and summary of the 2 operational Mars rovers and the current mission status.
I'll even excitedly look forward to "flags and footprints" and suborbital missions. Just fly...somewhere.

Offline Escapist

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It is incredibly difficult for someone like me - an enthusiast, surely, but not involved in the scientific or engineering communities - to keep up with all the various missions out there. It can also be a challenge for me to truly understand the significance of certain discoveries and temper what is surely overblown mainstream news coverage. Articles like this are the reason I subscribe to L2 on this site. The content here is just incredible, and presented in such a way that a neophyte such as myself can follow it easily. Not to mention that I do not have to deal with the sensationalism that is so rampant in other news sources.

Thank you for all the amazing work you do here at NSF, and keep it coming.

Offline savuporo

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very thorough, nice. I'm really liking these year in review detailed posts !
« Last Edit: 12/30/2014 11:49 AM by Chris Bergin »
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Offline scienceguy

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I think they need to send people to confirm whether there is life there.
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Offline Star One

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I 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.

Good article by the way.

Offline pagheca

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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.
« Last Edit: 12/30/2014 08:58 AM by pagheca »

Offline Star One

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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.:)
« Last Edit: 12/30/2014 01:22 PM by Star One »

Offline pagheca

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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.:)

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.
« Last Edit: 12/31/2014 08:50 AM by pagheca »

Offline Torbjorn Larsson, OM

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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.

We now know from the emerging field of replicator thermodynamics that the energy cost of replication (so not to dissociate as fast as it replicates) and exponential growth (so evolution emerges) necessitates NET out of the requirement of irreversibility. That in turn means you need a metabolic engine (electron bifurcating metal atoms) as a "trigger"*, and a CO2 carbon source and an NO2 electron sink out of volcanism works that engine.

Irreversibility also means emergence of life is a product of a dynamical system. So not improbable as some have claimed but same as evolution ascend Mount Improbable (MI) in small survivable steps. (A dynamical system has a finite phase space volume to return to indefinitely, so can't have an "improbable" target.)

And we can test this! Life emerged so fast on Earth that, as a simplest possible stochastic process model, you can use the sole observable data point to say that life emerges with fast repeated and/or much successful attempts to scale Mount Improbable. (This is the one case were statistics are lenient, just one data point is enough to push a process average back within control; here used for testing.) A paper did the test 2010, IIRC. YMMV, certainly not many people sat up and took notice.

Another way to say this is that physics is continuous. This is why we can live in free fall environments of space without having evolved for that environment, the environment we have evolved for is similar enough. And that is loosely how I interpret the article question here, in the same conditions expect the same results by continuity.

*Seeing how the process is broken down in small steps, I don't think of this constraint as much as a "trigger" as a contingent happenstance. The process is more akin to how a mountain chain grows when plates collide, and the NET results are used by exactly those who research geological systems as ancestors to life.
« Last Edit: 12/31/2014 03:18 AM by Torbjorn Larsson, OM »

Offline Oli

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Somewhat related:

"Detecting extraterrestrial life using mechanical nanosensors"

http://phys.org/news/2014-12-extraterrestrial-life-mechanical-nanosensors.html

Which made me wonder, how would Curiosity technically detect life on Mars? I mean actual living cells...
« Last Edit: 12/31/2014 03:41 AM by Oli »

Offline pagheca

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I 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 imagine what you are referring to but, not being my field, I may be missing something and would like to read the original papers.

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.

In general, however, I think that this emphasis on life is scientifically not really sound. I'll try to explain why.

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.

Note I'm not criticising the article. I do not because, as I say, there is some room for interpretation in this field and the rest is so wonderful and well written I can't really do that. As I said, "I" consider that statement a bit stretched as I think the question is misleading and when I talk to the general public 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.
« Last Edit: 12/31/2014 08:46 AM by pagheca »

Offline Dalhousie

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I 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.


It would be very difficult.  Even with unmanned MSR.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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.

Nobody has said it is the answer.  But it is certainly a question to be answered.  Whether in the affirmative or negative, the results are important.

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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.

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.

More evolved rovers are certainly something to look forward to, but they will still be very limited in every respect, limited in power, volume, mass, science capabilities, mobility, and bandwidth.  These are intrinsic limits.

As for comparing this to work done on the IS, it's apples and oranges.  The ISS does very different kinds of science. Also important, also interesting.  You might as well compare the work of Curiosity with that of Hubble.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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.:)

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.

In the literature you will see that four astronauts are a smallish crew (smaller have been discussed), six is typical and more than six is large.

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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

Since when has Curiosity cost 7 billion?

As for return, what Curiosity has achieved to date is equivalent to one EVA by a pair of astronauts with an unpressurised rover.

There is no question that a crewed mission would return orders of magnitude more data than the same amount spent on unmanned missions (in the unlikely event of that actually happening.

What is up for debate is whether societies want to know that much about Mars.  Up to know they haven't, so we make to with unmanned spacecraft and their limits.

Which is fine up to a point.  But sooner or later it will be time to move to the next level.

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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.

Funding for Curiosity has been approved through to 2016.  Whether they achieve the goals set for this period remains to be seen.  Despite the hype Curiosity fell well short of what was predicted before landing.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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I 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.

There certainly has been a lot of hype.  But the reality is it has taken 38 years since Viking to actually detect organic matter on Mars (claims of detection, generally disputed, have been made for Martian meteorites, telescopic and satellite observations).

We still don't know whether the martian organics are biogenic, Curiosity has the potential for doing so, but has not so far done it.  The latest organic results mentioned still are not published, and they will be subjected to ruthless criticism.

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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.

This is quite true.  Habitable does not equal inhabited. Mars appears habitable in the past, it is at best marginally habitable now, whether it is or ever was is something to be investigated.

How that organics have been confirmed instruments can be tailored to study those molecules.  It's probably too late for ExoMars, we will have to make do with what's been selected (which will still be very exciting).  But the proposed Indian and Chinese rovers and NASA Ames icebreaker mission will hopefully be able to incorporate the latest results.
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Offline savuporo

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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.
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.
« Last Edit: 12/31/2014 11:01 PM by savuporo »
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Offline Space Ghost 1962

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Despite 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.
« Last Edit: 12/31/2014 11:29 PM by Space Ghost 1962 »

Offline Dalhousie

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Despite 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.

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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.


No argument from me, it's been a successful mission, albeit a very expensive one.

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Likewise, 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.

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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.

No argument, although the Moon has been doing quite well in the past ten years or so!
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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.

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.

And it does so at a staggeringly slow rate.

Because hand help 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 day. Scientists operating a CheMin (commercially available as  Terra) can run scores of samples a day. Curiosity's ChemMin has run a handful in two years. 

Curiosity has in almost 29 months (844 sols today) documented three sites and is working on a fourth.  It has travelled 10.12 km, averaging about 12 m per sol.  Apollo 17 EVA 2 covered 20 km and documented eight sites.

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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.

Of course :) But the range of instruments suitable for unmanned missions is still very low.  It's not just instruments, its sample selection , sample collection, sample processing.  Field science is enormously complex from an operator point of view. And well beyond what is likely for the foreseeable future with any kind of robotics.  And of course you still don't get round the fundamental problems of latency.

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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.

Humans vs robots is a futile argument.  Nobody who argues for manned missions denies the importance of unmanned systems for a wide range of tasks.  They are the best we can do right now.  But to Martian geologists and astrobiologists  insisting this is all we should ever do (which is what the robots only lobby are saying) is like telling astronomers "no telescopes in orbit" or "no telescopes with apertures of more than 5 m".

AFAIK nobody has designed a 50 tonne unmanned Mars surface mission, even conceptually.  Which is unfortunate.  Would it be monolithic? Or multiple smaller landers?  Probably the latter I suspect.  We would certainly get a lot from 50 Curiosity sized missions, say 25 Curiosities, 12 2020 sample collection rovers and 12 sample return missions.  All up perhaps 500-600 km of traverse and 6 kg of returned sample.  Maybe twenty different instruments and sampling tools.

But there have been plenty of manned mission studies, we have a good idea what they will produce.  Even a conservative approach (2 EVAs a week with a four person crew will lead to more than a thousand km of traverse and hundreds of kg of sample over a 500 sol mission.  And would deploy thirty or forty instruments and sampling tools.

But until then I certainly appreciate what we are leaning now and will learn in the future.  Even if it is happening at (literally) a snail's pace!



"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline ThereIWas3

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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.
"If you want to build a ship, don’t drum up people to collect wood and don’t assign them tasks and work, but rather teach them to long for the endless immensity of the sea" - Antoine de Saint-Exupéry

Offline Dalhousie

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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.

Correct.  1) in particular was major screw up, hard to imagine  that nobody picked it up.

Unfortunately, the best science requires climbing the lowermost 880 m of the mountain, and the mission plan for the extended mission still includes this.  I have grave doubts whether the wheels will last survive the distance.  Happy to be wrong of course!

There are many other issues.

3. SAM is leaking reagents which contaminates the organic results.

4. There is a problem with the drill that threatens the mission every time it is used.  So there has been less sampling than intended.

5.  Progress is less than a third what was expected.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline savuporo

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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 day

That 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.
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Offline Dalhousie

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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.

No argument from me.  Mistrakes are what happen when you do something.  they only way to avoid them is to do nothing.  Curiosity has been a successful mission, despite the problems.  Hopeully it will be round for quite a bit more.

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>>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 day

That 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.

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 (it take 20 seconds a measurement).  A hand held XRF would be similar. So about 70 Whs for both (you can't going to run them continuously in the field)

As a field lab instrument (because of the sample preparation) a Terra uses up to 90 Wh, and can run for four hours on batteries, enough for dozen of samples. Between them these three instruments would use perhaps 400 Whs, 0.2 % of the power budget.

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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.

None of which will come near to what a scientist will get in the field.  None of which get round the problem of latency.  All of which cost subtantial $$$.  All of which are unworkable when you look at the numbers.

 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.

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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.

Thanks for the reminder.  It would appear this mission would offer little beyond the 2020 current MSR mission.  No increase in return (e.g. instruments, distance, returned sample).  I agree it's putting all the eggs in one basket.  Hopefully there will come a time when we will do such large unmanned missions, especially to places where we can't yet send people (e.g. outer planets).  But not yet.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline clongton

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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?
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Offline RonM

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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?

Excellent point. You either find complex organic compounds that might have been produced by living organisms or you see little things moving around under a microscope. Unfortunately, we cannot scan for life signs like they do in sci-fi stories.

As Carl Sagan wrote in Scientific American, “If a silicon-based giraffe had walked by the Viking Mars landers, its portrait would have been taken.”

http://en.wikipedia.org/wiki/Life#Definitions

Offline ThereIWas3

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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.
« Last Edit: 01/01/2015 05:42 PM by ThereIWas3 »
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Offline savuporo

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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 
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.

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None 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.

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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.

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Offline Space Ghost 1962

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Despite 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.

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.

In a like way with a new mission, the political reality is that MAVEN may be limited to a short science mission with its elliptical orbit necessary for its science instruments, for the incompatible data relay back-up function to protect the assets that need such. Such compromises, including a non steerable dish and lack of instrument articulation affect the potential science product, yet all are a part of the delicate nature of getting a planetary mission funded.

Such is life.

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Likewise, 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? 
Addressed to the presumed "science predictions" shortcoming.


However 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.

...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...

Nice post:
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None 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.
Yes, its not latency. It's being there - virtual reality is still virtual.

Doing field science is very different than remote science. By the end of Apollo we were doing baby steps in that direction - we still didn't have enough capability nor tools nor experience to have the effect that a scientist has in planning a trip to an arid desert and gathering samples "hit or miss" for days / weeks. Remote science can be enhanced, but it isn't field science, and field science will likely take multiple manned expeditions to Mars to reach Apollo levels.

Because planetary missions must return a proven value or have the Viking effect of a "funding desert" for decades, too much rides always on too little. Some say this was also true with Apollo, to a greater degree. Thus the dilemma.

If one speaks critically about this in the political side, you'll end up defunding everything, because they are stuck in unreality to begin with. So the windmills tilted at here as to remote science losses - they are acceptable given the human condition we're stuck with.

Funding planetary science has, unfortunately, a "gambling" aspect to it. Some part of the gamble is in developing scope of capabilities, some is in doing science, some in infrastructure, some in political "packaging", some in engineering challenges.

Offline Dalhousie

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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.

It would be good to see higher powered and less flimsy instruments on Mars. But if you think this will lead to a science return equivalent to a crewed mission, I suggest you do the numbers and show the your case.

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 traverse
1000 kg of surface science payload
400 kg returned samples
10 m drill depths

When you have done so, show us the numbers.  But not in this thread, this isn't the right place for it.

Good luck!


 
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline savuporo

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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 traverse
1000 kg of surface science payload
400 kg returned samples
10 m drill depths

With an IMLEO of 500 mT ?  :o
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Offline the_other_Doug

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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.
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Offline Dalhousie

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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 
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.

More power is only a small part of the issue.

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None 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. [/quote]

MATLAB?  What’s that?  (joke) I have been a scientist for over 30 years, and never used it. It’s completely irrelevant to what I do.  Jokes aside, you are right, what happens back in the lab is important.  But field science isn’t just done in the lab.  It starts the moment you look at an outcrop.  There is a vast amount of work involved in collecting data in the field, what data to collect, how to collect it, what instruments to use, whether it is worth sampling. The is a lot of contextural data to collect otherwise the results are worthless.  Latency is what makes it so slow, that and the inherent limitations of robotics.  That is why it has taken Curiosity two years to do what an astronaut tam could do in hours.

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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. 

No argument from me.  The technology investment to drive at that rate is called sending a driver.  If you think you can do that unmanned come up with a plan – and put numbers to it.

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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.

I didn’t think you were.  But DEXTRE shows how hard it is to match even some of the capabilities with telerobotics a space suited astronaut.  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. But manipulators that can do complex tasks end up being very large and very complex. And you will need to do many tasks.  Drill holes, scoop samples, pick up rocks ranging from small to large, deploy a wide range contact instruments even to difficult angles, hammer off samples, hammer in instruments.

It would take more than just pinpoint landing to have the ability to upgrade something on the surface of Mars.  That’s like saying all you need to upgrade Hubble robotically is do orbital rendezvous.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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.

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.

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However 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.

Given your definitions, fair enough.

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...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.

"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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 traverse
1000 kg of surface science payload
400 kg returned samples
10 m drill depths

With an IMLEO of 500 mT ?  :o

I would have said 650, but you can go for 500 if you like.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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.

There are measures that can be used, distance is one of them, I used it because it is a simple one to comprehend and compare.  There are others.  Number of samples collected, sites documented in detail,  papers published.   

The “primary mission goals” were so general they could have been met almost anywhere on Mars, certainly at any of the chosen landing sites. 

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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.

One would hope they were circumspect in actual planning.  However an example traverse with notional field sites published pre-launch clearly said that they would have travelled over 30 km by now, climbed over 800 metres, and characterised a dozen sites.

Where they are now is approximately sol 188.  Interestingly they also predicted this would be the fifth site, which is what Curiosity is on.  So in terms of sites they are on track, it’s just the rate of progress, both on traverse and the rate of site characterisation,, that is way off, by a factor of three or thereabouts.

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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.

Where they are now isn’t the foot of Mt Sharp, at best it is the base of a low rise that leads to the foot. That’s called shifting the goalposts.  There is no technically about it.  A gentle rise, with minimal dissection aren’t foothills, let alone the foot of a mountain.  A pediment, perhaps.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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I am certainly looking forward to the publication of the organics paper.  The methane results are out, and are very important, but organics in sediments are a real prize.  Hopefully not too much longer, as the site was sampled two years ago.

I hope they send it out for very critical review first, even before submission, because the knives will be out on this one. 

« Last Edit: 01/01/2015 09:59 PM by Dalhousie »
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Offline Space Ghost 1962

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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.

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
Not lying - it could drive at night. Not sensible from the start - who'd not use the instruments on all that interim terrain, and in using the instruments, require examination in daylight as well. Consider it a unused capability.

Perhaps if they encounter a long uninteresting feature they'll use it then. Remember, the group that built the spacecraft designed to required capabilities, and the group that targeted the mission judged the site as best allowing the mission to best be completed. Neither overlapped to make sure that the expectation of all capabilities would be used to garner the mission goals. Like with field science, where you bring along an instrument the entire way that you never end up using, because the situation turned out different.

As to less than genuine use of legislation / capabilities, that's not for me to judge the merits of. The matter has been raised from the beginning. If you are upset about this small example, in the greater context of the nation (or world), you must be either very upset very often, or completely shut in and ignorant of the larger, more common cases. Neither would I believe. Nor is it relevant.

If it matters, many had doubts about this. But the alternative is larger solar/batteries. Which may not survive "wintering". I guarantee with that radioactive source, there will be heat flow for this.

The point is we have demonstrated a capability that can be used where solar has insufficient power density.

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...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.

I do because I want missions to be funded by Congress, so you play by their rules. And like much in the way of science results, they are not being communicated back well, a chief limitation in planetary science, as I witnessed at the AGU yet again. I'm glad you're pleased, but I'm telling you they don't "get it", and if they don't "get it" they don't fund follow on.

The “Precision bombing" didn't yield as much science product as humor... completely missed me, I’m sorry.
S "Pete" Worden (see http://www.allreadable.com/77321U2H):
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Ames Research Center is go for the first precision bombing run on the moon.
... this in reference to various mission terminations to impact lunar features to toss up a debris cloud that may allow a dubious assay of a site. He thinks he's a wit ... he's half right.

Offline Vultur

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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.

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.)

Offline savuporo

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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.

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.)
That is where the discussion devolves into "my unicorns are better than your pixies".

I gave a little thought to the question above about what would a robotic Mars exploration program with hundreds of tons of IMLEO mass available look like, but there are so many hypotheticals in the question that it's not something you bash into a forum post or a blog post - it would be a short book if not more.

If you start comparing against something like NASA's Mars DRM 5.0 .. it is full of hopeful technology that does not exist today and needs to be developed. If it did exist, we would not be pondering this question and Mars would be a busy place.
One can napkin design a brute force, flight-proven technology only, robotic salvo architecture with what .. about 50 Curiosity-sized landers, but that too would be a fantasy only - nobody is going to pay $10B in launch costs only for lobbing so much equipment at Mars.
And even if it weren't, by the time your first rocket lifts off you would have revised the ideas - which is happening every month right now in organizations like MEPAG. Except that they are more grounded in reality and don't dream that much about orders of magnitudes of larger spending.

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.
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.




« Last Edit: 01/02/2015 03:41 AM by savuporo »
Orion - the first and only manned not-too-deep-space craft

Offline Dalhousie

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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.
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
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Oli

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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.
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

Ask a planetary scientist whether he wants to spend $100bn on robotic or manned Mars exploration. I think the answer is clear.

Even if time delay is such a huge issue, which I seriously doubt, you could operate robots in real-time from orbit. There is no need to go down to the surface.

Edit: Found an interesting paper on the subject (attached).

Evaluation of Human vs. Teleoperated Robotic Performance in Field Geology
Tasks at a Mars Analog Site


Paper is from 2002 for a 2015-class rover. Humans were limited to one three-hour shift per test site, while robot operators could have one or two thee-hour shifts.

Observations per unit time for the given test cases:

Remote-rovers, terrestrial-controlled (w/delays)
observation rate = 0.2
Remote-rovers, Mars-controlled (w/o delays)
observation rate = 1 (normalized)
Spacesuited human, observation rate = 5
Shirtsleeve - free human geologist, obs rate = 27

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.

« Last Edit: 01/02/2015 09:14 AM by Oli »

Offline pagheca

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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.

Some data behind opinions, at least. Thanks very much for that paper.

However, the problem is also that resources are limited: until someone demonstrates costs of manned space travel can be reduced by order of magnitudes, not a 10 or 20 (or even 50) percent, because funding for space exploration are very limited the cost of even a minimalistic manned Mars mission would drain anything else, with a huge loss for science.

We have to select our target between economically feasible missions, not only high benefit/cost missions.
« Last Edit: 01/02/2015 06:26 PM by pagheca »

Offline matthewkantar

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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?

Reality is our first few stabs at rovers have shown that it is possible for them to work for ten years on the surface of Mars. 250B in investment in unmanned gear could have tons of samples back here on earth, core drilling to many meters depth, improved Mars orbit relay sats, etc etc. I understand the intense desire for feet on the surface of Mars, but in my opinion you get much more bang for the buck with bots.

Matthew


Offline ThereIWas3

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That Apollo required humans on the Moon to get their results is not really relevant to this discussion, as computer and communication capabilities of 50 years ago (when Apollo was being designed). are simply laughable by today's standards.  I was in college during Apollo, and my University had one of the most powerful mainframe computers commercially available in its computer center.  It filled a room.   Any typical smartphone today is 1000 times more powerful and fits in your pocket.   Similar advancements have been made in sensors and actuators.

The problem with solar power on Mars, as experienced by the MER rovers, was not night, but winter.  They had to hibernate thru the cold, and one of them never woke up.   Either you need much larger panels (not practical on a rover) or nuclear power.  A fixed heated garage /recharge station with big panels would be nice, but we are not to that point yet.

I am convinced that until the unmanned missions return enough information to make manned missions more widely supported, there will be no funding from the US Congress for manned missions at all.
"If you want to build a ship, don’t drum up people to collect wood and don’t assign them tasks and work, but rather teach them to long for the endless immensity of the sea" - Antoine de Saint-Exupéry

Offline Vultur

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I don't think manned Mars missions really need much undemonstrated technology. You just have to be more minimalist and accept a bit more risk. No artificial gravity, no special GCR protection (solar flare shielding only), and so on.

The two things that are really "new" are landing a larger payload and (for the cheaper Mars-Direct-type mission) ISRU on Mars. But those are only weakly "undemonstrated"; propulsive landing is pretty well known by now and doing it in Mars gravity and atmosphere should only help (less wind force/gravity etc.) and we have pretty good data from the many unmanned Mars landings. And the chemistry needed for ISRU is also well known.

Offline Vultur

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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.

Maybe it really would cost $500 billion if it was totally planned by NASA, from the launch vehicle on up. But if the infrastructure was mostly provided by someone like SpaceX... no way.

IIRC Mars Direct was supposed to be $30-50 billion. Reusable Falcon Heavy could probably cut that.

Quote
How long would this manned mission dwell on the surface, a few months at most?

IIRC opposition class is supposed to be something like a year.

Quote
Would science even allow a manned mission before we know what damage we would cause by contaminating the planet with humans and their byproducts?

Well, "science" doesn't allow or disallow things.

But I don't think it would matter. Existing unmanned landers contaminate the environment with pretty reactive propellants, and they probably aren't completely bacteriologically clean either despite efforts.

And the bacteria thing probably doesn't matter much. Current tech would easily distinguish between Earth imports, Mars native life, and Mars life descended from a transfer from Earth in the distant past. (A simple DNA test is sufficient - if it doesn't fit on Earth's tree of life or doesn't have DNA at all, it's a true Mars native; if it belongs on Earth's tree of life but is very distant from known things, it's an import in the distant past; if it's a known species or closely related to known human-commensal species, it's a recent import/contamination).

This sort of thing wasn't possible back in the early Space Age; back then contamination would have been a huge problem for finding life. But since metagenomics was invented... not really.

Online Chris Bergin

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.

Offline pagheca

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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.

Sorry Chris, but this has rather been an interesting discussion about the pro and con of rover vs. human exploration of Mars (see for example the very interesting paper reported by Oli), with both the parties well represented and no references to HSF in general.

Representing some people like a "gang" because of their opinions is quite unfair IMHO.
« Last Edit: 01/03/2015 07:22 PM by pagheca »

Offline vulture4

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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.
« Last Edit: 01/03/2015 09:40 PM by vulture4 »

Offline Dalhousie

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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.

ChemCam is probably one of the biggest technological innovations of the mission, well worth repeating in the future because it gives non-contact geochemistry.  But it doesn't do mineralogy, one of the biggest drawbacks of the instrument suite of Curiosity  is it lacks the ability to do either remote and contact mineralogy.  Mineralogy and geochemistry are not the same, different minerals can have the same chemical compositions (e.g calcite and aragonite are both CaCO3).  Glasses may show the same composition as crystalline rock with with very different implications WRT genesis. 

Quote
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.

The real latency for Mars isn't the comunication lag but the twice a day time comms slot.

For the past 60 years we have been promised that level of  AI in the next decade or so.  We are still waiting.  Certainly neither ExoMars or the 2020 rover, or the proposed Chinese or Indian rovers will have it.  That takes us out to the 2020s.

What we are more likely to see is improved autonomous navigation allowing longer drives and some degree of onboard classification of data highlighting features of interest.  These have certainly be trialled by ExoMars testbeds.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Star One

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Offline Dalhousie

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People might also be interested in an earlier paper in the same journal on MISS in the 3.5 Ga Dresser Formation in WA.

http://online.liebertpub.com/toc/ast/13/12

The paper shows what can be learned when you can study the material properly (macrophotography, photomicrographs, thin sections, laser Raman imagery, structural analysis).
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Torbjorn Larsson, OM

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(Sorry for a late response. Life intervened.)

I 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.

For the thermodynamics of replicators and the stability of their exponential increase (at best), see Pascal "Suitable energetic conditions for dynamic chemical complexity and the living state", Systems Chemistry; Pross (et al) on the same subject. England has a good paper on why RNA is uniquely suited as the first catalytic self-replicator.

For the likelihood, see Spiegel and Turner http://arxiv.org/abs/1107.3835 . If you want to test it, replace their bayesian model with hypothesis testing. (Or use bayesian ratio testing.)
« Last Edit: 01/08/2015 11:16 AM by Torbjorn Larsson, OM »

Offline Torbjorn Larsson, OM

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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.
« Last Edit: 01/08/2015 11:51 AM by Torbjorn Larsson, OM »

Offline pagheca

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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.

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?

Offline Star One

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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.

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.

Offline Dalhousie

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Curiosity chief scientist responds to Noffke paper.

http://www.space.com/28218-mars-rover-curiosity-signs-life.html

He could not really say anything else.

"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Star One

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Curiosity chief scientist responds to Noffke paper.

http://www.space.com/28218-mars-rover-curiosity-signs-life.html

He 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?
« Last Edit: 01/10/2015 08:43 AM by Star One »

Offline Robert Thompson

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England has a good paper on why RNA is uniquely suited as the first catalytic self-replicator.

I cannot locate this. Link please?

Offline Dalhousie

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Curiosity chief scientist responds to Noffke paper.

http://www.space.com/28218-mars-rover-curiosity-signs-life.html

He 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.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Star One

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Curiosity chief scientist responds to Noffke paper.

http://www.space.com/28218-mars-rover-curiosity-signs-life.html

He 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.

Offline the_other_Doug

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Curiosity chief scientist responds to Noffke paper.

http://www.space.com/28218-mars-rover-curiosity-signs-life.html

He 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 really don't think it's appropriate to question the science team's decisions.  We don't have the full picture that they use to make their decisions.  And when you open up that can of worms, you get to dealing with the people who are seeing everything from alien technology to little critters in the pictures.  There was indeed someone who, upon seeing a rock that seemed to inexplicably move (and was later shown to have been moved by the rover's wheel) actually filed suit in federal court to try to force the applicable science team to follow the science plan he wanted to dictate to them.  The suit claimed that NASA and JPL were guilty of gross malfeasance for not recognizing obvious living creatures in the pictures, or something like that.

In that kind of environment, with every nutcase looking over their shoulders, the science teams do well to simply make their own decisions as best they can and not worry about criticisms from those who have no idea of the constraints they face and the data they already have in hand.
-Doug  (With my shield, not yet upon it)

Offline Dalhousie

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Curiosity chief scientist responds to Noffke paper.

http://www.space.com/28218-mars-rover-curiosity-signs-life.html

He 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.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline NovaSilisko

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I 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?

Offline Dalhousie

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I 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.
« Last Edit: 01/12/2015 09:23 PM by Dalhousie »
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Offline NovaSilisko

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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.

So... what happens when the fault does strike? Is it just the drill that's busted, or the whole vehicle?

Offline Dalhousie

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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.

So... what happens when the fault does strike? Is it just the drill that's busted, or the whole vehicle?


If you believe this story, best case you loose the drill (and any ability to analyse rock with SAM and CheMin with it), worse case is you lose the mission.  http://www.space.com/18834-mars-rover-curiosity-drill-break.html
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Offline Torbjorn Larsson, OM

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Oy, late again!  :-[

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...

If you find that interesting, make sure to look up Lineweaver et al on a similar model. [I think it is referenced in my previous ref.] As soon as you have repeated emergence attempts, the likelihood for life is not negligible anyway.

Mainly, as soon as you have a dynamical system with a finite phase space volume as "target" of interest, you don't get a likelihood approaching zero to hit it. Or, said differently, if you have a repeatable process it would be very finetuned to produce precisely one (or zero or a few) individual results.

I never understood the references to Monod, he seems to have been a philosopher that claimed that life is unlikely (random result).  :o That is not what you expect from a geophysics viewpoint.

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.

England has a good paper on why RNA is uniquely suited as the first catalytic self-replicator.

I cannot locate this. Link please?

A perspective article here: https://www.quantamagazine.org/20140122-a-new-physics-theory-of-life/

The published paper here: http://www.englandlab.com/uploads/7/8/0/3/7803054/2013jcpsrep.pdf

Offline Torbjorn Larsson, OM

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Curiosity chief scientist responds to Noffke paper.

http://www.space.com/28218-mars-rover-curiosity-signs-life.html

He 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 am glad we cleared that up, because Vasavada's claim that it "probably" don't have a biological origin is not neutral.

NASA's McKay and geomicrobiologist Boston says differently in an article referenced in NASA's astrobiology portal:

"“I’ve seen many papers that say ‘Look, here’s a pile of dirt on Mars, and here’s a pile of dirt on Earth,’” says Chris McKay, a planetary scientist at NASA’s Ames Research Center and an associate editor of the journal Astrobiology. “And because they look the same, the same mechanism must have made each pile on the two planets.’”

McKay adds: “That’s an easy argument to make, and it’s typically not very convincing. However, Noffke’s paper is the most carefully done analysis of the sort that I’ve seen, which is why it’s the first of its kind published in Astrobiology.”"

"“The fact that she pointed out these structures is a great contribution to the field,” says Penelope Boston, a geomicrobiologist at the New Mexico Institute of Mining and Technology. “Along with the recent reports of methane and organics on Mars, her findings add an intriguing piece to the puzzle of a possible history for life on our neighboring planet.”"

[ http://www.astrobio.net/news-exclusive/potential-signs-ancient-life-mars-rover-photos/ ]

So we have one neutral commentary, where I had thought the Curiosity team would land ("we need to investigate more, the sample return mission would be excellent for that, let us take that possibility (MISS at lakes/playas) to the site selection process for the 2020 sample rover"), and one lauding, as contrast.

I don't want to speculate in individual actions. (Beware of applying statistics of population behavior on individuals!  ::)) That is why I let science writer Paul Anderson do it instead.  ;D He has now written a comment under Wall's article:

"I've been in touch with Nora Noffke regarding this re my own article(s) for my blog The Meridiani Journal as well as AmericaSpace. She doesn't think the Curiosity team (and she knows a lot of the members) has even read her full paper yet, which is lengthy and goes into a lot of detail. She also noted that no one from Space.com had contacted her re this update, to get her side. The Curiosity team may or may not be right, but she is a very respected geobiologist, so they should be taking her findings into account if they haven't already, especially after acknowledging that they *could have* looked at the features more closely, but didn't. Vasavada's background is geology and physics, but not biology or geobiology. Noffke's hypothesis deserves to be looked at and tested if possible, that's all. The Curiosity team's reaction comes off as more of a casual dismissal than based on specific rebuttals."

[ http://www.space.com/28218-mars-rover-curiosity-signs-life.html?fb_comment_id=fbc_870092566374435_870927902957568_870927902957568 ]

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?
« Last Edit: 01/13/2015 06:24 PM by Torbjorn Larsson, OM »

Offline Dalhousie

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Bit more on the organics story.

http://www.nasa.gov/content/goddard/mars-organic-matter/#.VLWMVCuUfLG

As far as I can see from this the detection is the same as that reported in the original Sheepbed member paper, over a year ago.  What they have done is more work using simulants that, in their view increases the probability that the chlorinated hydrocarbons are indigenous, not contamination.

Still no word on a new paper to explain more of this, so it is a case of science by media release.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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?

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.

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Offline Star One

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« Last Edit: 01/13/2015 10:11 PM by Star One »

Offline NovaSilisko

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« Last Edit: 01/13/2015 11:28 PM by NovaSilisko »

Offline Star One

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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.html

http://m.huffpost.com/us/entry/6425392

http://io9.com/this-curiosity-image-suggests-microbial-life-once-exist-1677739858

Uh oh... almost time for misinformed reporters to take it as an absolute fact that these structures were formed by life.

Some might argue that's no better than dismissing it out of hand that it has received in some other quarters.

Offline NovaSilisko

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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.
« Last Edit: 01/14/2015 06:27 AM by NovaSilisko »

Offline Star One

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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.

It's just the author of the report seems well respected and therefore not someone to be lightly brushed aside. As you say maybe the attention its gathered will garner further investigation, especially if as mentioned above she intends to pen a response to what the Curiosity team are reported to have said in reply to the original article.

Offline Dalhousie

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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/
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Offline Torbjorn Larsson, OM

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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?

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.


Thanks for the response! So they are playing ass covering politics by inserting the unnecessary "probably". That is a shame. [Here I am, speculating all the same. But I feel provoked by their overreach.  ???]

Noffke has been on record (in the web interview I think) that she saw similar features later in the traverse but in so bad condition so she wouldn't have wanted to write a paper about it.

Possibly they surface in the climb after passing the current lake sediments, if the fossilization was so extensive.

I 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.
« Last Edit: 01/15/2015 10:34 AM by Torbjorn Larsson, OM »

Offline Torbjorn Larsson, OM

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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/

Yeah, that is what I referred to earlier. But I would say that McKay is favorable on the paper but neutral on its findings, Boston is gushing on the latter.

Offline Vultur

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Why doesn't NASA send an actual life detection mission? The state of the art in microbiology & especially extreme environments has advanced so much since Viking it isn't even vaguely comparable (they didn't even know about chemosynthesis when those experiments were designed!)

Offline QuantumG

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Why 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.
Non-commercial spaceflight and filicide  http://tylervigen.com/view_correlation?id=185

Offline Tetrakis

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As someone who runs gas chromatography/mass spectrometry experiments quite a bit, I was initially skeptical of the detection of martian chlorobenzene and other chlorinated hydrocarbons. I'm accustomed to seeing all sorts of polychlorinated/polysilylated organics coming through the GCMS as "noise" resulting from traces of manufacturing lubricants or solvents.

Then again, the isotope ratios in the organics is pretty convincing. Accepting that the organics originate on Mars, it surprises me that an appropriately reducing environment which would allow for the formation of hydrocarbons could be so oxidized to be full of what is, for all intents and purposes, bleach. Is there literature on how an environment devoid of free oxygen could produce hypochlorite or perchlorates? Where did the evidently high levels of Martian perchlorates come from?
« Last Edit: 01/17/2015 04:17 AM by Tetrakis »

Offline the_other_Doug

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That has been what has been niggling at the back of my mind for a while.  The oxidation of the Earth's surface materials that is still strongly seen in many exposed oxidized iron-bearing strata across our globe only began after the "great oxygen catastrophe" that occurred after photosynthetic life evolved and changed the basic chemistry of our atmosphere.

Could the oxidized mineralogy seen on Mars have happened in the absence of abundant free oxygen in the early Martian atmosphere?  And if not, then what besides photosynthetic life could have caused Mars' own oxygen catastrophe?
-Doug  (With my shield, not yet upon it)

Offline Tetrakis

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Brief Googling seems to have placed me at the top of "Mount Stupid":

http://faculty.washington.edu/dcatling/Catling2010_AtacamaMarsPerchlorate.pdf

The gist of the paper is that ancient volcanic chlorine and/or ongoing photochemical generation of oxidizing species (O, superoxide, H2O2, O3) in the arid environment should be sufficient for the observed levels of perchlorate on Mars. There is little direct evidence for this atmospheric photochemistry on Mars, though, because the oxidizing species in question are both low in concentration (even relative to methane) and short-lived. Especially eye opening is that similarly high levels of perchlorate can be found in the Atacama desert.

Offline Vultur

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Why 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!
« Last Edit: 01/18/2015 07:17 PM by Vultur »

Offline whitelancer64

Why 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.
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Offline pagheca

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Why 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.
« Last Edit: 01/18/2015 08:51 PM by pagheca »

Offline Vultur

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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.

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).

Quote
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.

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.

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. :) )

Yeah, but unless it's based on evidence, that doesn't mean anything. When you look at the sort of conditions endoliths and some sub-surface microbes in Antarctica live in, and compare them to conditions likely under the Martian surface, I don't see why life should be unlikely.

Life developed really fast on Earth, so Mars's brief period of more or less 'earthlike' conditions probably isn't a barrier to life starting. The questions are: how likely is the origin of life, and how quickly could primitive life develop an endolithic/subsurface mode of life?

(and that doesn't even consider endolith transfer from Earth to Mars via meteorites...)

Offline hop

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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. :) )
I don't think much of the community would dismiss the possibility of life hanging on somewhere, but virtually none would expect it to be the just kicking around in loose surface regolith. If there's life, it's almost certainly underground and mostly isolated from the surface.

For a life detection mission to be justified, there would need to be a compelling case that a specific, accessible environment was presently habitable.

The other thing the "why hasn't NASA..." question misses is how NASA science missions are actually selected. The broad science goals of NASA led missions defined by the science community, through the decadal survey.

The decadal put priority on sample return, not some "life detection" mission, so NASA can't just go out and decide to send a life detection mission. Someone could propose one for Discovery, but without a compelling target it would have no chance of selection, and plausible targets would likely exceed Discovery budget.

Offline whitelancer64

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.

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).

Quote
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.

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.

i'm not saying that we shouldn't send "life detection" type experiments to Mars, we absolutely should. but you need to not set them up as a "life detection" mission - because they won't be that.

the simple answer to your question "Why doesn't NASA send an actual life detection mission?"

is that we don't have any simple answers to the questions "what is life?" and "how do we detect life?"

so you need to set up the expectations for such a mission to be realistic. there is no magical "life detection" box we can send to Mars. any such experiments would have sets of strengths, weaknesses, and limitations.

for example, if the Life Marker Chip (LMC) experiment were sent to Mars, its detector is based on antibodies that react to very well understood immune functions - and would do very, very well at detecting life here on Earth. so if Mars life is similar to Earth life, it has a good chance to detect it. but if not, it won't detect Mars life, even if it is there.
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Offline Dalhousie

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Why 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.

We don't know that there is nothing there.  There is a good chance that there once was life, and a lower chance it is still there.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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Why 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.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Star One

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Why 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.

Offline pagheca

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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.

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

Quote
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.

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.
« Last Edit: 01/19/2015 09:14 AM by pagheca »

Offline Star One

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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.

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

Quote
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.

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. Nor does one singular informal poll prove much of a data baseline to extrapolate any change of belief in the matter. As for the rest well we'll just have to agree to disagree on the reading of the situation.

Offline pagheca

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Which is not the impression of what your position was in your OP.

That's right. In fact I wrote "I'm not embracing one or another position on this quest at this point".

I am not afraid of changing opinion based on new evidences. Nobody should if based on scientific reasoning.
« Last Edit: 01/19/2015 10:18 AM by pagheca »

Offline Dalhousie

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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.

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.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Star One

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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.

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.

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.

Offline Dalhousie

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I 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.

For a sample collection mission what you need are a set of instruments to 1) select the best samples to return and 2) characterise their context.  Since samples with high astrobiology interest will also be important this means the the following

a) Pancam or similar
b) Microscopic imager of similar.
c) Contact or remote geochemical instrument
d) Contact or remote mineralogy instrument
e) Contact or remote organic instrument
f) sample collection tool (probably drill)

There may be other instruments of course but they are bonus.  I can't see this changing much.

If we look at the 2020 rover we currently have

a) SuperCam, Mastcam-Z
b) SuperCam, Mastcam-Z?
c) SuperCam, PIXL
d) SuperCam, SHERLOC
e) SHERLOC

Bonus: RIMFAX, MEDA, MOXIE

IMHO, what may change is what is consdiered a good site.  Given the high cost, high risk and high return nature of MSR there may well be pressure to go to an already visited site rathwer than risk somewhere new. DSome maybe a return to Gale or peraps the ExoMars site (assuming its flown or successful).





"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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.

Here's a photo I took yesterday of biofilms (dark grey or green) at Paraki stream, a boiling acid-chloride spring (pH 2).  We know there were silica (opal) deposits on Mars, we have seen them on OMEGA and CRISM data.  We have seen one close up at Homeplate.  Similar springs were the earliest habitats for life on Earth.  So the fact we have habitable environments on Mars in the past means we should at least look.  Negative results will be just as important as positive ones, which is why we need to look hard, it being very difficult to demonstrate a negative. 

Which is why positions that say "everyone knows there is no life" are really annoying, they are not based on facts and are poor science.
« Last Edit: 01/19/2015 05:52 PM by Dalhousie »
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Offline pagheca

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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.

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...

Offline Dalhousie

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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.

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...

Sorry, I never meant to imply you were of the "there is no life " school.  Apologies for the confusion!
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline the_other_Doug

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...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."

The only way to graduate from one paradigm to a better, more truthful one is by questioning, and sometimes even attacking, "what everyone knows."

It gets very, very frustrating in re Mars because there are large numbers of scientists who seem to continually resist the opening up of pro-life paradigms, either past or present.  For example (and these are generalities, off the top of my head, not presented to start minutae arguments over citing papers where someone said this versus when someone else said that, etc.):

- Mariner 9 sees obvious river valleys -- they say "everyone knows Mars is too arid and has too thin of an atmosphere for liquid water.  These valleys must have been caused by something else."

- The Viking orbiters see well-developed catastrophic flood basins (first recognized, if somewhat preliminarily, in Mariner 9 images) -- they say "everyone knows if Mars ever had liquid water, it couldn't have been enough to have caused catastrophic floods, since there's just not that much water ice in the poles.  These flood plains must have been caused by something else."

- The Viking 1 lander sees some rocks that look suspiciously like water-formed conglomerates -- they say "there can't have been enough water to have promoted the formation of such rocks, that has to be a breccia or an ashflow tuff, or again, something else."

- The Pathfinder lander sees excellent examples of large rock transportation during catastrophic flood events -- they say "those rocks could have been tossed there by impacts.  Or ejected from volcanoes.  Unless you tell me where all the water came from and went to, it can't have been catastrophic floods, it must have been something else."

- Mar Global Surveyor provides tons of detailed images of topographic features that, as far as photo-interpretation can do so, absolutely lock up the case for flowing water on Mars -- they say "it has to have been basal surges from volcanic eruptions and large impacts, they could have carved all of these features without needing to invoke liquid surface water, and everyone knows liquid water can't exist on the surface of Mars."

- Mars Odyssey provides proof of massive amounts of water ice in the polar caps and strong suggestions of massive amounts of subsurface ice and icy regolith, especially under the northern plains -- they say "all you see is hydrogen, that might have some from something else."  (Notice that at this point, "must" starts turning into "might" or "likely" because the missing water has essentially been fund.  dvd)

The MER rovers, MRO and MSL have been nailing the lid on the issue of paleo-waters on Mars.  We have massive data now that prove that liquid water has been present all over Mars -- and some (though in dwindling numbers) still rail against these findings, taking as their bases that since Mars cannot now support liquid surface water, then we cannot without "exceptional proof" accept that water ever flowed there.

And now, we can detect that methane blooms still occur on present-day Mars, in a cyclical pattern.  The methane source could be biological (i.e., coming from present-day Martian life) -- but they say "everyone knows Mars is too cold, has too little air, no liquid water and a hazardous radiation environment.  The methane can't be from biological sources -- it must be caused by something else."

I wonder, will this be the final fallback position of the professional doubters?  They have dwindled, as the data has continued to support the model of an early warm, wet Mars.  But the doubters remain, carping at the heels of the approaching paradigm shifts and clinging desperately to "what everyone knows."
« Last Edit: 01/20/2015 04:40 AM by the_other_Doug »
-Doug  (With my shield, not yet upon it)

Offline pagheca

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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."

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.
« Last Edit: 01/20/2015 02:32 PM by pagheca »

Offline the_other_Doug

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Don'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...  ;)
-Doug  (With my shield, not yet upon it)

Offline Star One

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Don'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...  ;)
What we think of Mars and its potential for past and existing life seems to change every twenty to thirty years roughly. Going almost from one side to the other on the matter, from the canals of Mars of the late nineteenth century to the dead world of the seventies to current times of stronger belief in life. Unfortunately I don't think a final answer on this is as close at hand as some think, extraordinary claims needing extraordinary evidence something that we probably don't have the tools in situ at this time to deliver to a higher enough standard for a majority of the scientific community to accept.

Offline JasonAW3

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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."

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).
My God!  It's full of universes!

Offline Dalhousie

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Don'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...  ;)

Some people seem make a pleasure of contradicting the bleeding obvious.  The dry pyroclastic flow people being a case in point. :)
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline Dalhousie

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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."

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).

Mars was thought be be highly habitable long before the "canals" - which were a red herring to end all red herrings.
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Offline meekGee

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Sometimes, even in the scientific circles, people have a pre-conceived notion, and fall into the pattern of constructing arguments to support that notion - instead of constructing their notions based on the findings.  This is the difference between an argument and a debate.

For example, we all know that there are "Mars-firsters" and "Moon-firsters" out there, but your position on the strategy of solar system exploration should NOT affect your interpretation of Mars surveillance data. And yet, draw a random sample in any conference, and by a wide margin Moon-firsters will argue against (or just belittle) water-on-Mars, and Mars-firsters will do the same for water-on-the-moon.

Not to mention people who are (sub-consciously even) rare-earth advocates.

It is human nature.  Good thing we have enough advocates in both sides that the drive for more evidence does not die, and eventually, the truth emerges.  Flat-earth, for example, is almost completely discredited by now.
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Offline pagheca

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There is a logic trap in this.

Discovering life would be much simpler - epistemologically - than demonstrating there isn't and there has never been life on Mars. For the first, you need a single positive, for the second, even scanning the whole planet surface, or at least the most likely areas (basins, etc.) wouldn't be enough as there is always the possibility of a warm cave or an habitat at 100 or 300 m below the surface (or fossils somewhere behind the surface, admitting life evolved at such a point to allow fossilization).

So, I wonder how do we set the threshold to say that there is not and/or there has never been life on Mars.

This is relevant as the interest in Mars rather than in other celestial bodies is driven in part by its relative accessibility, in part by this planet being the most "habitable" in the Solar Planet but, in part, by the popular interest on searching for life past and present, that allow to obtain funding relatively more easily than for other probes.

The risk is to spend a lot of money on this (rather than on other accessible targets, like the very often cited Moon) and still demonstrate nothing.

« Last Edit: 01/22/2015 07:07 AM by pagheca »

Offline QuantumG

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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?
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Offline Star One

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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?

Such supposed surety of facts is not welcome in science especially in something like this.

Offline pagheca

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I was not suggesting any conclusion about life on Mars, I swear :). I just wanted to suggest a someway weird logical problem in this quest.
« Last Edit: 01/22/2015 11:36 AM by pagheca »

Offline zubenelgenubi

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re: past generations of astronomers and life on Mars

Some astronomers saw canals-as-engineered-features on Mars.  But, there are other examples.

The "waves of darkening" observed advancing across a particular hemisphere's spring, and the recession of the darkening correlating with that hemisphere's autumn.  The darker regions looked greenish because of contrast effects to the regular reddish surface.

I believe this was eventually determined, in the Space Age, to be the movement of dust on the surface, not the growth and withering of plant life.  It was seasonal.

Spectroscopic bands of water vapor in the Martian atmosphere were telescopically observed.  I believe this was later determined to be water in our own atmosphere.

"Sinton bands" were observed in Martian spectroscopy, which were taken as spectroscopic observation of chlorophyll on the surface.  I believe that this was later determined to be a spectral band of deuterated water vapor in the Martian atmosphere (D-O-H instead of H-O-H).  Or maybe the DOH was in our own atmosphere?

These items were all still in the astronomical mix when Mariner 4 flew by Mars in 1965.

The above examples are all IIRC.  Please comment if I have incorrectly recalled.

(I'm not gunning for astronomers, but coming from an astronomy background, I know about some of the discipline's collective goofs over the centuries.)

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Zubenelgenubi
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Offline QuantumG

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Finding life on Mars doesn't imply an independent origin.
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Offline pagheca

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Finding life on Mars doesn't imply an independent origin.

Of course, but you have to admit it _could_ . In any case it would be of extraordinary importance to find life on another planet, no matter why.

The problem is we can demonstrate life exist, but not that it doesn't and it didn't there.

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