Despite the hype Curiosity fell well short of what was predicted before landing.
Quote from: Dalhousie on 12/31/2014 10:39 pmDespite the hype Curiosity fell well short of what was predicted before landing.Your other criticisms are well founded. This isn't.
Curiosity's instrument package was well along before Phoenix's results addressed Viking's questions effectively. It was too far along to allow a complete redesign and requalification, not to mention implicit regulatory issues that would be created by such a late change. It was either fly or not fly. I'm glad they flew and are getting a science product. It is too early to conclude Curiosity's impact on planetary science.
Likewise, it is unmanned or nothing. I prefer unmanned. Ask me again when manned becomes possible.
All in all, funding planetary landing missions are really unpredictable. Too much rides on too little, too few, too infrequent. That is the top issue, and has been before Viking, as far as Mars. Mars is the best case too - the Moon, Venus, rest of planets/moons too (excepting Huygens on Titan) ... haven't got squat in comparison.
Quote from: Dalhousie on 12/31/2014 10:24 pmDo you realise how limited the science done by Curiosity actually is? For example for mineralogy we have had only four analyses published to date, in over two years. Two of sand, two of rock, of sites sampled two years ago.I'm wondering : if you have a human operating the same data acquisition tools that Curiosity was given ( because of obvious payload limitations ) and relaying back data at the same rate, how would you expect to get more science done ? Because that is all that Curiosity does, it acquires data and sends it back to earth where the actual "science" gets done.
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.
If you designed it for more bandwidth/power/payload with more in-situ instruments available etc then it would be sending back a lot more, of course.
EDIT: i dont mean this as a humans vs robots argument actually. I think it is obvious that that if you allocate mass budgets on the scale that is required for human missions, you will get proportionally larger returns too. Apollo went to the moon with 50 tons TLI, if you ever decide to send so much equipment to Mars, prepare to be amazed. Manned or unmanned.
Curiosity is severely mass restricted. This has turned up in two major effects so far.1. The wheels were made too thin and get damaged by sharp rocks. This has required choice of alternate routes.2. The power source is very weak. So the rover moves sloooowly.The delay in reaching further up the mountain is also because Curiosity found something very interesting to study along the way, and has actually already confirmed some of the things it was sent to study.The goal is not to climb the mountain. The goal is to learn.
I'm no fan of Curiosity's cost, or even in general how NASA today runs surface missions. But i don't see how any of the shortcomings or oversights could be fixed by anything but flying more, more frequently, and invest much more in capability enabling technologies.
>>Because hand held instruments equivalent to most of Curiosity's (say a Niton XRF or an ASD spectrometer, which has no counterpart on Curosity) can collect hundreds of readings a dayThat is useless if you don't have power budget to actually run the instruments the or bandwidth and power budget to actually send the data back. An astronaut similarly handicapped wont be able to do more either.
If you want more capable science missions, invest much much more in enabling technology : laser communications and full-coverage relays, things like ASRG or the thermoacoustic alternatives, enabling precision landing technologies like DSAC and ALHAT so on surface mission staging and capability build-up becomes possible, more flexible robotics with changeable effectors ala DEXTRE. And many more.And at the end of the day, you are always mass limited no matter what you do, so to get more, fly more.
As for 50-ton TLI missions - the only thing i saw was the reference to 2024+ "one shot MSR" launched by SLS that was supposedly put forth by MPPG but is incredibly light on the specifics and looks more like cocktail napkin. I dont think that is a good way to use funds or payload mass - too much riding on one rocket failure.
Really good article Chris. Really good. One of the best I have ever seen on the rover. Thank you.I do have a question however which wraps directly into some of the statements wrt "life". Can anyone actually define what life is and is not? What is the chemical difference between a live animal and a dead one? Can we measure that? Sure we know it when we see it (on earth) but can you measure it? What is the chemical composition of "life"? How do we test for it? AFAICT all we can really do is to test the environment for chemicals that usually accompany *earth-based* life - as we know it. But as for testing anything and actually identifying "life", I do not believe that is possible. Nobody today can actually define what life is, let alone test for it. We can test for and identify the presence of every element in the periodic table, but "life" is not on that table. It's not an element. How do we test for it?
Crewed missions have power budgets of the order of 200 kWhs per sol, so the power demands of hand held instruments are trivial... An off the shelf hand-held spectrometer uses about 8 Whs and and can run for 4 hours on batteries, enough for thousands of readings
None of which will come near to what a scientist will get in the field. None of which get round the problem of latency.
DEXTRE masses 1.56 tonnes and uses an average of 1.4 kW, it requires direct teleoperation and has so far failed to live up to expectations (it was supposed to replace up to 50% of EVAs). Hardly an alternative.
Quote from: Space Ghost 1962 on 12/31/2014 11:28 pmQuote from: Dalhousie on 12/31/2014 10:39 pmDespite the hype Curiosity fell well short of what was predicted before landing.Your other criticisms are well founded. This isn't.I suggest you read the pre launch and pre landing predictions on where Curiosity would have been by now. In 2010 Curosity team members were making presentations saying that the rover would have travelled more than 30 km and climbed more than 800 m by now.The pre-landing press kit had scaled this back somewhat, but was still predicting that Curiosity would be in the foothills by now.
QuoteLikewise, it is unmanned or nothing. I prefer unmanned. Ask me again when manned becomes possible. At present it is indeed unmanned or nothing. Half full is better than none at all. Have I said otherwise?
However manned missions to Mars are technically feasible now.
...although the Moon has been doing quite well in the past ten years or so!
QuoteNone of which will come near to what a scientist will get in the field. None of which get round the problem of latency. I'm not entirely convinced that latency is that big of an obstacle for science - which gets done with MATLAB in months after the data collection anyway. Data acquisition lag of a few minutes does not damper paper publishing rate by a lot.I understand everyone wants more data and faster - the way to get more data is build a more powerful machine, and while you are at it don't make its wheels out of beer cans. If you want more traverse to get more data from different locations, then actually invest in mobility - there is no fundamental technical reason why you couldn't drive across Mars at miles per hour, but you do need to make the technology investments.
If you want high-powered instruments on Mars, then send high-powered (and less-flimsy) instruments to Mars. There is no need to send people to operate them - the cost would be many orders of magnitude greater because the people would probably want to come back, require lots of Oxygen and Food and DVDs of "Three's Company" while they are there, etc etc.
We know what a crewed mission is likely to achieve, there have been innumerable studies. Here is the target to aim for.1000 km of traverse1000 kg of surface science payload400 kg returned samples10 m drill depths
Quote from: Dalhousie on 01/01/2015 05:00 amCrewed missions have power budgets of the order of 200 kWhs per sol, so the power demands of hand held instruments are trivial... An off the shelf hand-held spectrometer uses about 8 Whs and and can run for 4 hours on batteries, enough for thousands of readings Uh .. so the logical argument here is for more power on surface. I.e. basically what every mission planner always wants anyway .. There are only so few ways to have more power ( humans and horses dont help with that ) - more solar either from ground or orbit, or more nuclear with better efficiency.Exactly what ThereIWas3 said here too, if you want more power, send more power.
I understand everyone wants more data and faster - the way to get more data is build a more powerful machine, and while you are at it don't make its wheels out of beer cans. If you want more traverse to get more data from different locations, then actually invest in mobility - there is no fundamental technical reason why you couldn't drive across Mars at miles per hour, but you do need to make the technology investments.
Quote DEXTRE masses 1.56 tonnes and uses an average of 1.4 kW, it requires direct teleoperation and has so far failed to live up to expectations (it was supposed to replace up to 50% of EVAs). Hardly an alternative.I think you misread - i'm not proposing sending DEXTRE to mars, robotic arms can be built as big as small as needed - see Curiosity or Yutu. What i'm saying is designing for more dexterous and modular robotics opens up new ways of capability expansion. By sending more tools to DEXTRE arsenal you can make it do things that it was not originally planned to do.But that presumes pinpoint landing ability - again a technical investment milestone, nothing to do with manned missions.
So by "predictions" you mean "rate of progression of travel". Took it to mean "science predictions".These were absurdly high to begin with, to justify the "nuclear" power instead of solar. At one point banking much on driving through the night. How do you do science while driving through the night? Personally expected a fractional improvement over Opportunity/Spirit, while also a decrease due to a more elaborate science package requiring more "non driving time". There are political aspects to missions that intrude on reality. I would class this under that.
Quote from: Dalhousie on 01/01/2015 12:01 amHowever manned missions to Mars are technically feasible now. "Theoretically" I'll buy. "Technically" no way - too much in the way of undemonstrated/unproven capability. Worse - no political will to fund - a necessary part of "technically" in my book.
Quote from: Dalhousie on 01/01/2015 12:01 am...although the Moon has been doing quite well in the past ten years or so!Hardly - cheap missions. No American lander/rover. Chinese with Yutu rover best example. "Precision bombing" didn't yield as much science product as humor...
Quote from: Dalhousie on 01/01/2015 08:06 pmWe know what a crewed mission is likely to achieve, there have been innumerable studies. Here is the target to aim for.1000 km of traverse1000 kg of surface science payload400 kg returned samples10 m drill depthsWith an IMLEO of 500 mT ?
I don't think it's reasonable to judge Curiosity's "progress" simply by how far it has traveled. After the initial analysis of findings at Yellowknife Bay, the science team announced that they had found clays and many indicators of an ancient habitable environment there, so the primary science mission of Curiosity had been accomplished, and without even requiring her to ascend 800 meters up the side of Mt. Sharp. There was even talk about reworking the driving plan and staying primarily in the Yellowknife complex for the remainder of the mission.
Also, every pre-planned route I've ever seen has carefully omitted a lot of details on exactly when the rover would arrive at any given point, with footnoting galore warning that any major finds along the way might delay the overall traverse progress. When you don't know what you're going to find over the next rise, it's hard to be real accurate when it comes to predicting where you'll be 50 or 100 sols from now.
Besides, from the press releases I've read, they're considering the Pahrump Hills, where they are spending a lot of time right now, as being in the foothills of Mt. Sharp. So, technically, they have reached the foothills by now.