Author Topic: FEATURE: Curiosity confirms organics on Mars; Opportunity’s 10 year anniversary  (Read 41646 times)

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 »
"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

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