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  #91 (permalink)  
Old 28-November-2007, 08:24 PM
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Well, that is what we are talking about, isn’t it? If we want to send men (and women ) to Mars, we have to find out a lot more about Mars. We have to find suitable locations for a base and for a colony. Robots will do that.
I agree. But not the robots we're currently sending, as great as they are.
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  #92 (permalink)  
Old 28-November-2007, 10:04 PM
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I'm not in agreement with your cost estimates, nor with your assessment of the risks.

Thy cost estimates are based on:

MSL - rounding of current estimates (1.7 billion and climbing).

MSR - statement by Mark Adler of the MER project at a lecture I attended this year, and supported by http://www.space.com/missionlaunches...rn_000929.html . People keep trying to do it for less but indital claims of 1-2 billion soon climb up to the 5 or 6 billion once realistic estimates are made.

Crewed Mars mission. I used the Mars Oz reference mission as a baseline, which sends 250 tonnes to Mars. Per kg cost estimates for large crewed missions range from the ISS (212,000) to Apollo (342,000). These were obtained by dividing current program cost estimates by payload mass (LEO payload mass or payload mass sent to the Moon) and adjusted for inflation if required. The ISS, which uses mostly existing technology would be the low end estimate, Apollo. which developed everything from scratch, the high end. That gives 53-86 billion. I quoted a mid range figure as a Mars mission will require a mix of existing and new technology.

Now show what is wrong with my facts, reasonign, or calculations.

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I'd also like to point out that I expect our ability to do interesting work with robotic missions is likely to improve dramatically over the next thirty years.
There will be improvements, but what is your evidence that they will improve by two or three orders of magnitude? people have been predicting such performance for 50 years. We don't haved it yet, and we don't know to get it. What if your hope is wrong?

Conversely we do know that with existing and developable technology will put people on Mars at no greater risk than we currently accept.

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Also, all of your claims about available power and mass of sample returns could be done with larger robotic missions for much less cost than a humans with life support mission.
This is not supported by the evidence. First of all deep drilling is well beyond the capability of existing robots. Despite there being a lot of investment in this technology. Robotic vehicles that can traverse thousands of km are still a pipe dream, despite massive investment.

Robots can't do science. They can collect data, but the science is done at the end of a time delay. that is why, despite nearly 40 years of robotic developments still can't match the capabilities of the teloperated Lunakhods. The Lunakhods were more than 10 times faster than what is predicted for MSL.

Lastly robotic missions are more expensive per kg than human ones. Stationary landers cost about $1 million per kg on Mars, rovers $2 million. averaging everthing to payload sent to Mars robotic missions average $500,000 per kg, almost twice what human missions cost.

For large scale Mars exploration, it is cheaper, faster, and better to send people.

Jon
  #93 (permalink)  
Old 29-November-2007, 01:57 AM
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But our current robots are not doing that (looking for bases locations, etc.) They're looking for microbial life and the remains thereof. That was my original point. The issue is not that the current probes aren't useful; it's that they're rolling down a rabbit trail. Digging twenty centimeters into the Martian dust will not make it easier for a human to dig a twenty-foot hole and analyze the sediment levels, now or thirty years from now.
Which is truly unfortunate. If we plan to send men to Mars, we should start ASAP in looking for base and colony locations with robots. Once we get men on Mars, we can look for signs of life etc a lot more efficiently.
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  #94 (permalink)  
Old 29-November-2007, 01:58 AM
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I agree. But not the robots we're currently sending, as great as they are.
Agreed. That’s why we need Goliath and Big Al.
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  #95 (permalink)  
Old 29-November-2007, 02:32 AM
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There will be improvements, but what is your evidence that they will improve by two or three orders of magnitude?
I believe the increase was comparative performance, as has been demonstrated over the past 30 years. While computer and robotic advancements are driven by literally hundreds of thousands of potential uses, rocketry advances are extremely limited in application. Since the trend in rocketry applications is unlikely to increase significantly, and since there is every reason to expect the trend in computers and robotics to continue to increase significantly, it is reasonable to conclude that robotics technology will continue to increase far more rapidly than rocket technology.

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This is not supported by the evidence. First of all deep drilling is well beyond the capability of existing robots.
Only because deep drilling robots have nor had a need to be developed. But all the technologies to develop them already exist. They need only to be combined.

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Robotic vehicles that can traverse thousands of km are still a pipe dream, despite massive investment.
The military now has many robotic vehicles, such as R-Gator, Black Knight. Other vehicles such as Terra Max have shown that autonomous robotic vehicles are possible with current and emerging technology.

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Robots can't do science. They can collect data, but the science is done at the end of a time delay.
And there is no reason a sophisticated robotic rover could not do the same. With an onboard science lab, samples can potentially be subjected to hundreds of different scientific tests.

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The Lunakhods were more than 10 times faster than what is predicted for MSL.
And Goliath is predicted to be 20 times faster than the Lunokhods.

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Lastly robotic missions are more expensive per kg than human ones.
Logically, robotic missions to Mars would be far less expensive than manned missions. Without all the life support required for humans, and without the return vehicle and fuel, robotic missions would be a LOT less expensive.

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For large scale Mars exploration, it is cheaper, faster, and better to send people
That depends upon when the exploration is to take place, and what the purpose of that exploration would be. Initially, large robotic rovers would be far more practical for finding, and perhaps even the initial preparation of colony sites. Later, after people are living on Mars permanently, and can take time away from merely surviving, THEN manned expeditions across the Martian surface will be more practical. IMEHO
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  #96 (permalink)  
Old 29-November-2007, 09:17 AM
JonClarke JonClarke is offline
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I believe the increase was comparative performance, as has been demonstrated over the past 30 years. While computer and robotic advancements are driven by literally hundreds of thousands of potential uses, rocketry advances are extremely limited in application. Since the trend in rocketry applications is unlikely to increase significantly, and since there is every reason to expect the trend in computers and robotics to continue to increase significantly, it is reasonable to conclude that robotics technology will continue to increase far more rapidly than rocket technology. [/QUOTE]

Impressive though the advances in robotics have been they have not translated into impressive progress in terms of field robotics on the surface of the Moon or Mars. MSL the most advanced planetary rover so far developed, will have less exploration capability than the Lunakhods 40 years before.

Rocketry does not need to advance to get people to Mars. The technology of today (and 30 years ago), is more than adequate.

Conversely the last 30 years have seen major advances in most of the other space flight necessary for humans to go to Mars. Long duration human spaceflight, management of multi year missions, large scale solar power production, orbital assembly, high efficiency life support, knowledge of the surface of and atmosphere of Mars. The main areas of development pending are EDL, rovers and suits. None of these require break though science, simply application and development of what we now know.

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Only because deep drilling robots have nor had a need to be developed. But all the technologies to develop them already exist. They need only to be combined.
There has been extensive research on such technology. It has failed to deliver anything reliable beyond a couple of metres. Which is a pity, because there have been times when i could have used such a rig. Whereas a simple human operated rig can drill hundred metres.

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The military now has many robotic vehicles, such as R-Gator, Black Knight. Other vehicles such as Terra Max have shown that autonomous robotic vehicles are possible with current and emerging technology.
Terra Max crashed spectacularly as I recall. Not exactly a useful system as yet.

In autonomous mode R-gator carries out simple repetitive tasks, not complex exploration. It can move at only a quarter the speed it can be driven by a human operator. It can run for only 8 hours and needs for than a kW to run its electrical system.

Furthermore it operates in close cooperation with people. In fact, it is an excellent example of the type of robot vehicle that would support a human mission as an unpressurised rover with some specialised autonomous capability. it's not a question of humans or robots, but using both to their best ability.

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And there is no reason a sophisticated robotic rover could not do the same. With an onboard science lab, samples can potentially be subjected to hundreds of different scientific tests.
What is the evidence that sophisticated robots will be able to do sophisticated tests? You will always need scientists in the loop deciding which sites need to be visited, what samples should be collected and which tests should be done on them. With the time lag this will always be slower than with people on site. Even advanced robots can’t circumvent the speed of light.

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And Goliath is predicted to be 20 times faster than the Lunokhods.
I hope you are not trying to highjack the discussion onto your hobby horse.

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Logically, robotic missions to Mars would be far less expensive than manned missions. Without all the life support required for humans, and without the return vehicle and fuel, robotic missions would be a LOT less expensive.
This is not logic, this assertion. It is a fact that robotic missions cost twice as much per kg as human ones. For example:

MGS cost $538 million and massed 1,031 kg in LEO, and therefore has an LEO cost per kg of $522,000

MO cost $348 million and massed 725 kg in LEO, and therefore has an LEO cost per kg of $480,000

MRO cost $720 million and massed 1,180 kg in LEO, and therefore has an LEO cost per kg of $610,000

Phoenix cost $386 million and massed 680 kg in LEO, and therefore has an LEO cost per kg of$567,000

The combined MER cost was $900 million and they massed 2,126 kg in LEO, and therefore had an LEO cost per kg $423,000

MSL has an estimated cost of $1.7 billion and a LEO mass of 3,400 kg in LEO, and therefore has an LEO cost per kg $500,000

(All costs adjusted for inflation to 2006-2007 $)

Average cost per in LEO (exclusive of the EDS) is therefore $500,333.

For comparison the average per kg cost of the ISS and the entire Apollo program is $235,955, just over half the cost of unmanned missions.

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Originally Posted by MentalAvenger View Post
That depends upon when the exploration is to take place, and what the purpose of that exploration would be. Initially, large robotic rovers would be far more practical for finding, and perhaps even the initial preparation of colony sites.
This is what the current generation of rovers is doing, in part. Testing the ground and preparing the way for future crewed missions.

Jon
  #97 (permalink)  
Old 29-November-2007, 07:34 PM
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Impressive though the advances in robotics have been they have not translated into impressive progress in terms of field robotics on the surface of the Moon or Mars.
That is no reflection on the possible use of robotics, but rather a reflection on how the PTB chose to apply the technology. Your argument does not address the practicality of robotics for Mars missions.

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Rocketry does not need to advance to get people to Mars. The technology of today (and 30 years ago), is more than adequate.
Adequate, yes. But isn’t the inefficiency (and therefore cost) of current rocketry often cited as one of the main reasons we are not already on Mars?

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Conversely the last 30 years have seen major advances in most of the other space flight necessary for humans to go to Mars. Long duration human spaceflight, management of multi year missions, large scale solar power production, orbital assembly, high efficiency life support, knowledge of the surface of and atmosphere of Mars. The main areas of development pending are EDL, rovers and suits. None of these require break though science, simply application and development of what we now know.
I have been supporting that viewpoint for years. But it is irrelevant to this question because the same can be said for robotics. We can build them. We have the technology. We simply need to apply it properly.

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There has been extensive research on such technology. It has failed to deliver anything reliable beyond a couple of metres. Which is a pity, because there have been times when i could have used such a rig. Whereas a simple human operated rig can drill hundred metres.
Goliath could carry a rig that could drill 20 feet in a single pass. The only restriction on drilling deeper is robotically adding sections of drill pipe. We have a machine here that bores 50-100 ft under streets to lay cable. The only thing the human operator does is drop another section of pipe onto a tray. The machine does the rest. A robot could drop a pipe onto a tray.

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Terra Max crashed spectacularly as I recall. Not exactly a useful system as yet.
Irrelevant. Some of our most sophisticated and reliable technology had early failures, some of them quite spectacular.

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What is the evidence that sophisticated robots will be able to do sophisticated tests? You will always need scientists in the loop deciding which sites need to be visited, what samples should be collected and which tests should be done on them. With the time lag this will always be slower than with people on site.
True. However, the people need to sleep and rest, while the robot can work 24 hours a day. I’d say that more than makes up for the time lag.

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This is not logic, this assertion. It is a fact that robotic missions cost twice as much per kg as human ones. For example:
MGS cost $538 million and…. yadda, yadda, yadda….
MO cost…. yadda, yadda, yadda….
Phoenix cost…. yadda, yadda, yadda….
Etcetera, etcetera, etcetera………………
That is perhaps one of the most representative examples of the Logical Fallacies of Hasty Generalization and Misapplied Generalization I have seen. You have taken a variety of programs spanning 45 years, with incredible changes in technology, major changes in the driving political and economic climates, and many different types of delivery systems. That isn’t apples and oranges, that is apples and quartz and squid. Adjusting the dollars is irrelevant, because the other variables are so incredibly disparate. The comparison should be the difference between manned and robotic missions using the same base technology in the same time period.

Logically, robotic missions to Mars would be far less expensive than manned missions. The food, water, oxygen, and living facilities alone would make human missions more expensive. If you leave the crew on Mars, they have to have huge amounts of supplies. If you bring them back, you have to have a return vehicle, more supplies, and fuel. That makes the manned mission even MORE expensive.

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Originally Posted by JonClarke View Post
This is what the current generation of rovers is doing, in part. Testing the ground and preparing the way for future crewed missions.
Hardly. None of the current generation of rovers is going to verify a settlement site, which will be the most difficult and most critical part of early exploration. There is very little more that we need to know before simply sending a flags and footprints mission to Mars.
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  #98 (permalink)  
Old 30-November-2007, 12:33 AM
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There are two main issues here:

(1) Putting humans on Mars just for the sake of doing it, and/or for colonization, etc.

(2) Scientific study of Mars by robots vs human astronauts.

For the former, the relative science benefit and pros/cons of humans vs robots is less a factor. Humans are going there anyway in this scenario.

For the latter, the issue is how to maximize the science return per invested dollar, independent of whether humans go to Mars.

It seems clear robots are far more cost efficient than humans if science results per dollar is the primary goal.

We must remember little actual science will be done on Mars by either humans OR robots. Rather the data is captured and most of the actual scientific work is done on earth.

Humans are basically fragile biological robots in that role. On orders from earth, they deploy instruments, turn knobs, throw switches, take samples, etc. Robots can do similar things without the vast overhead needed to support humans on Mars.

The projected timeframe must also be specified in any comparison of human vs robot science return per dollar. This is because of the continuing rapid progress in computer and robotic technology. IOW, a recent time estimate for a realistic manned Mars mission is 2031 or 2037:
http://news.bbc.co.uk/2/hi/science/nature/7116834.stm
http://afp.google.com/article/ALeqM5...uI4rNSCpCl3TTQ
http://www.nasaspaceflight.com/content/?cid=5048

We know what humans will be like in 2037: about like today. Rockets will be somewhat similar. By contrast robotics and computers progress very quickly and will be much more advanced. Already IBM's Blue Gene/L has simulated half a mouse brain: http://news.bbc.co.uk/1/hi/technology/6600965.stm. Blue Gene/P is about 6x as fast: http://en.wikipedia.org/wiki/Blue_Gene. We obviously won't be sending a supercomputer to Mars, but what supercomputers do today, a smaller computer can do in a few years. There are even informed projections that computers may mimic aspects of human intellect by the 2030s: http://www.jetpress.org/volume1/moravec.htm

On the robotic front, Honda's Asimo gives some idea of where things are headed. Anyone who thinks "robots couldn't do this or that on Mars" should examine this closely:
http://video.google.com/videoplay?do...267825427&q=as

Now, there are various videos showing Asimo falling down and malfunctioning. But he's a prototype -- not remotely intended for production use. The key is NOT what can he do today, but at the current rate of computer and robotic progress, what could his successors do in 2037?

Re deep drilling, innovative robotic methods are now being developed for use on various planetary bodies, including Mars: http://www.honeybeerobotics.com/idds.html

Re the limitations of CURRENT unmanned terrestrial vehicles, this has little to do with an advanced Mars rover in 2037, for several reasons:

(1) Progress is rapid in computers and robotics. Limitations or failures today mean little for 2037.
(2) Terrestrial unmanned vehicle trials such as the DARPA Grand Challenge (http://en.wikipedia.org/wiki/DARPA_Grand_Challenge) are totally autonomous. The ground rules don't allow human intervention -- at all. By contrast a Mars rover is under earth control, using automation for limited periods. If it encounters problems it just waits for assistance. Of course by 2037, a Mars rover might need little assistance.

Re a manned mission being able to take more data, more images, etc, that's simply not true. An example of this is the Mars Reconnaissance Orbiter. It takes vast numbers of high-resolution images. Putting a human in Martian orbit to control the imaging would not improve things.

Whether in orbit or on Mars' surface, robots can stay there so long and take such high quality data precisely because humans ARE NOT there. The payload isn't squandered on humans and their support needs but can be dedicated to the scientific mission.

Putting a human on the surface would have some benefit in gathering data. But it is titanically expensive. For the cost of a manned mission (and probably at a fraction of that), a series of unmanned missions could gather far more and higher quality data.

We have already transitioned to mostly unmanned robotic exploration of the deep ocean. Decades ago, we'd send a manned deep submersible. We no longer do that, rather we use unmanned remote vehicles. It's not as exciting, but it's cheaper, safer, and we get excellent results. Likewise there's no serious plan for manned exploration of Venus, Mercury, Jupiter, etc. The entire solar system will be explored exclusively by robots, with the exception of earth's moon and Mars. We could probably put a human on Mercury or Venus, it would just be incredibly expensive. But we get better science return per dollar by using robots. The same is true for Mars.
  #99 (permalink)  
Old 30-November-2007, 12:51 AM
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Well said, joema. Thank you for all the great information.

That Asimo video is almost spooky to watch. It makes you think there must be a person inside that suit.
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Old 01-December-2007, 06:21 AM
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It seems clear robots are far more cost efficient than humans if science results per dollar is the primary goal.
Evidence? Certainly robotic missions can collect some data about Mars more cheaply than human missions. But for detailed scientific studies of Mars or the Moon human presence is far superior.
We need to send people… But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans. Steve Squyres Discover magazine interview June 2004
http://www.discover.com/issues/jun-0...over-dialogue/
We are constantly aggravated by the fact that all the questions we have about Mars could now be answered by Ken and me if we could just walk around on the planet for a few days….But for about two years now Malin and I have been absolutely convinced that we're going to have to send people there. Ken Edgett National Geographic, February 2001.
…human exploration coupled with sample return unquestioningly results in the most profound scientific understanding of a planet... they are essential. ...the "New View" of the Moon that has resulted from the entire range of exploratory tools and cross-disciplinary studies has been eye-opening. It points compellingly to a model for how future planetary exploration should be conducted. Because we now know how to do it right: what kinds of missions and (in hindsight) in what order…. There is no substitute for the ultimate mobile sensor: a human... if the Apollo experience taught us anything it is that the human ability to recognize interesting features quickly and then independently act to follow up on that information can lead to important discoveries... Ross Taylor et al., Reviews in Mineralogy and Geochemistry 60, 657-704, Mineralogical Society of America, 2006.
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We must remember little actual science will be done on Mars by either humans OR robots. Rather the data is captured and most of the actual scientific work is done on earth.
Robots do no science at all, they just collect observations. For field geology and biology they collect that data slowly, clumsily, and inefficiently compared to what human crews could do. This is a documented fact from the Apollo missions and from terrestrial comparisons. Despite 30 years of advances autonomous robots still cannot do as well as teleoperated machines either on other planets or on Earth. Another 30 years might bring autonomous performance up to teleoperated levels. It might not. Even then they will not perform as well as humans on the spot because of the time lag between the sensors and the people actually doing the work. Having humans on the spot will not only collect better data faster but allow on the spot science to be done, as well as much better science back home because of more and better quality data, and larger, better selected and contexturalised samples.

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Humans are basically fragile biological robots in that role. On orders from earth, they deploy instruments, turn knobs, throw switches, take samples, etc. Robots can do similar things without the vast overhead needed to support humans on Mars.
Robots have limited dexterity, mobility, dexterity, adaptability to unexpected surfaces compared even to a gloved astronaut. One reason why the robotic Hubble servicing mission was dropped in favour of a human one was because it would do less with a lower probability of success.

How big an overhead will a human mission need? More than a robotic mission certainly. But robotic missions have huge overheads too. About 4000 people are or have been involved in the MER missions. A human mars mission might have 10 times or 100 times as many people working on it. But it will be at least a thousand times as productive.

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Originally Posted by joema View Post
The projected timeframe must also be specified in any comparison of human vs. robot science return per dollar. This is because of the continuing rapid progress in computer and robotic technology. IOW, a recent time estimate for a realistic manned Mars mission is 2031 or 2037:
http://news.bbc.co.uk/2/hi/science/nature/7116834.stm
http://afp.google.com/article/ALeqM5...uI4rNSCpCl3TTQ
http://www.nasaspaceflight.com/content/?cid=5048
We know what humans will be like in 2037: about like today. Rockets will be somewhat similar. [/QUOTE]

Spacefaring will be considerably advanced in 30 years time over what it is at present. We don’t need more advanced rockets than we have already to get to Mars.

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Originally Posted by joema View Post
By contrast robotics and computers progress very quickly and will be much more advanced. Already IBM's Blue Gene/L has simulated half a mouse brain: http://news.bbc.co.uk/1/hi/technology/6600965.stm. Blue Gene/P is about 6x as fast: http://en.wikipedia.org/wiki/Blue_Gene. We obviously won't be sending a supercomputer to Mars, but what supercomputers do today, a smaller computer can do in a few years. There are even informed projections that computers may mimic aspects of human intellect by the 2030s: http://www.jetpress.org/volume1/moravec.htm
All very interesting, but what they mean for actual robot performance on the surface of Mars is just speculation.

Mouse brains don’t do science. A computer of Blue Gene performance would enhance the performance of a human crew even more that it would a robotic mission. In fact computers of such capability would generally require a protected environment to operate – like a human habitat. Fast computer speed is good, but it does not do science, only provide a better tool for people to use.

Predictions of mimicking the human intellect have been made before, so far with little to show for it. And what does “mimic” actually mean? AI research has given us search engines which mimic the human intellect’s ability to search and correlate information but much faster. But it still does not mean your PC does research. What it does is give better tools for people to use.

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Originally Posted by joema View Post
On the robotic front, Honda's Asimo gives some idea of where things are headed. Anyone who thinks "robots couldn't do this or that on Mars" should examine this closely:
http://video.google.com/videoplay?do...267825427&q=as
Completely irrelevant to Mars exploration. No payload. Can only move on flat surfaces. Needs near 400 watts to run. Has an endurance for less than an hour. Such a machine is useless on Mars.

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Now, there are various videos showing Asimo falling down and malfunctioning. But he's a prototype -- not remotely intended for production use. The key is NOT what can he do today, but at the current rate of computer and robotic progress, what could his successors do in 2037?
His successors will be doing well if they could mimic what MER can do now. The MERS are much more power efficient, have unlimited endurance, diverse payload, can cross wide ranges of surfaces – rocks, steep slopes, sand. A much better question will be what MERs successors be capable off in 2037? IMHO, based on extrapolation past progress and current options, is that they might be able to mimic the performance of a teleoperated rover on the Earth of the Moon. But they will still be well below what a human could do driving the same machine.

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Originally Posted by joema View Post
Re deep drilling, innovative robotic methods are now being developed for use on various planetary bodies, including Mars: http://www.honeybeerobotics.com/idds.html
A contract to research technology does not equate with such technology being actually feasible. It will certainly be very slow. So far the ability to drill even 10s of metres has been unrealised. Two m is about the limit for robot technology. Whereas a trailer mounted rig operated by a human crew can drill 10’s of metres in a few hours.

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Originally Posted by joema View Post
Re the limitations of CURRENT unmanned terrestrial vehicles, this has little to do with an advanced Mars rover in 2037, for several reasons:

(1) Progress is rapid in computers and robotics. Limitations or failures today mean little for 2037.
Progress is indeed to expected. Experimental technology now indicates what operational technology may be capable of it 10-20 year’s time. It might be another 10 years before such technology is space qualified. So hopefully vehicles with autonomous speeds measured in kilometres rather than metres might be practical in 30 years. They might not too. Driverless cars have been actively researched for 30 years, and are still not operational.

Even if this technology is available in 30 years, such vehicles will still need to consult with mission control on important decisions, which immediately inserts 10-40 minute delays even for quick decisions. A decision that would a person on the spot 5 seconds would take 10 to 40 minutes Plus every science operation will require constant supervision from Earth, and that is where the time delay becomes crucial. Operations that would take an astronaut a few minutes would take days.

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(2) Terrestrial unmanned vehicle trials such as the DARPA Grand Challenge (http://en.wikipedia.org/wiki/DARPA_Grand_Challenge) are totally autonomous. The ground rules don't allow human intervention -- at all. By contrast a Mars rover is under earth control, using automation for limited periods. If it encounters problems it just waits for assistance. Of course by 2037, a Mars rover might need little assistance.
Autonomous navigation will be very useful for many applications, not least for direct human exploration. But exploration is a lot more than being able to navigate a route. I can do that without much conscious thought. Exploration is an activity that is orders of magnitude beyond simple driving. It requires interpretation, understanding, knowledge, and experience, and something which will always be better done by a person on the spot than with a time lag.

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Re a manned mission being able to take more data, more images, etc, that's simply not true. An example of this is the Mars Reconnaissance Orbiter. It takes vast numbers of high-resolution images. Putting a human in Martian orbit to control the imaging would not improve things.
MRO is an excellent example of a mission that is ideally performed by an unmanned spacecraft. This is not the sort of mission I or anyone else who has written on Mars exploration has advocated in the past 30 years. We are talking about surface missions.

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Whether in orbit or on Mars' surface, robots can stay there so long and take such high quality data precisely because humans ARE NOT there. The payload isn't squandered on humans and their support needs but can be dedicated to the scientific mission.
The point is the MERs don’t get high quality data. The handful of instruments they carry are roughly equivalent to what an astronaut would carry on a pedestrian EVA to do a quick characterisation of the samples and their context. Compared to a pedestrian EVA they cover only 5-8 metres a day, instead of several km. Not that you could send people to Mars simply to do pedestrian EVAs. They would have unpressurised rovers which could cover tens of km a day, carrying more instruments than MSL. They would have pressurised rovers that could explore hundreds of km from the landing site. They would take samples back to the station and run chemical analyses that include trace elements, rather than just the majors. They could process large samples to get truly representative measurements. They could cut thin sections of the samples for petrographic work. They could run thousands of samples to chose the best samples to bring home – and bring back hundreds of kg. The human payload is not squandered but invaluable.

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Putting a human on the surface would have some benefit in gathering data. But it is titanically expensive. For the cost of a manned mission (and probably at a fraction of that), a series of unmanned missions could gather far more and higher quality data.
A human mission to Mars will not be titanically expensive. Using per kg costs and reasonable mass estimates a human mission would cost 70 billion. Spread over a 10 years development period this is the cost that is currently being spent on human missions. Unmanned missions are roughly twice as expensive per kg. I have already shown good reason why this is the case.

In the politically unlikely event of similar moneys being spent on an unmanned, 70 billion might buy you 10 large rovers and sample return missions. These would achieve far less than a single human mission of the type described. They might cover between them several hundred km and return a few kg. The human mission would explore thousands of km and return hundreds of kg. Plus those samples would be characterised by people on the spot with a vast array of instruments, not working through a 40 minute time delay with a limited suite of tools. Plus the human mission would investigate a whole range of issues regarding human settlement potential which no unmanned mission can ever do.

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We have already transitioned to mostly unmanned robotic exploration of the deep ocean. Decades ago, we'd send a manned deep submersible. We no longer do that, rather we use unmanned remote vehicles. It's not as exciting, but it's cheaper, safer, and we get excellent results. Likewise there's no serious plan for manned exploration of Venus, Mercury, Jupiter, etc. The entire solar system will be explored exclusively by robots, with the exception of earth's moon and Mars. We could probably put a human on Mercury or Venus, it would just be incredibly expensive. But we get better science return per dollar by using robots. The same is true for Mars.
ROVs and AUVs are enormously useful machines that greatly expand our capabilities to explore the oceans. But they have not replaced saturation divers, hard suits, surface ships, nuclear submarines, submersibles, they complement them. Furthermore most underwater robots are in fact teleoperated, taking advantage of real time human decision making and judgement. AUVs do very simple tasks. Teleoperation is going to be very important on Mars, as an adjunct to human exploration, not as an alternative.

As for crewed missions to Mercury of Venus, I agree there is no reason (at present) for human missions there. I don’t know anyone who is seriously suggesting them as a goal. These are missions indeed best served by robots. The Moon, Mars, and near earth asteroids are different. They can be reached using present day or near present day technology. Their environments are relatively benign and full advantage can be taken of relatively unimpeded human presence in every respect.

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Old 01-December-2007, 06:35 AM
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This will be my last post for a week or so, I am away.

I am a great advocate of using the right mission for the task. For a great many missions robots are ideal - remote sensing, geophysical and meterological networks, reconnaissance. But there are also roles for which human crew are unequalled, this is the opinion of everyone I know who actually works in field robotics and in planetary science. Not there is not a place for humans in such missions. Robotics and teleoperation would greatly improve the effectiveness of such missions, just as they do today in underwater exploration and on the ISS.

But I would like to know why the "robots only" advocates are so adamant in their hostility to any human role in exploration and pin so much hope on quite speculative capabilities of robotics 20-30 years down the track?

Mike Griffin once wrote about the "real" as opposed to the "legitimate" reasons for space exploration. The "real" reasons were those that meant that in the end people want to see humans in space, on the Moon, Mars, and beyond for emotional and ideological reasons as well as the "legitinmate"reasons of science, and strategy. The vehermence of the opposition to human missions from some suggest that there are similar "real' reasons being held against human presence, as well as the "legitimate" (but sometimes erroneous) reasons that robots are faster cheaper better. I would like to know what these real reasons are. Is there a deep seated sense that people should stay on Earth, a belief that technological evolutionwill supercede biological evolution?

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Old 01-December-2007, 07:12 AM
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why we need a man on Mars ?
We don't NEED a man, a woman would be fine.
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Old 01-December-2007, 08:17 AM
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Evidence? Certainly robotic missions can collect some data about Mars more cheaply than human missions. But for detailed scientific studies of Mars or the Moon human presence is far superior.
We need to send people…
Of course, but all in due time. The exploration of Mars to determine the best sites for colonization is best left to the robots. It is a long ranging, but not very detailed study that is needed for this. Later on, when humans are living on Mars in colonies, THEN is the time for detailed human exploration. When people have the time to explore, instead of spending most of their time ensuring their very survival, then they can go on detailed, extensive explorations.

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Robots do no science at all, they just collect observations. For field geology and biology they collect that data slowly, clumsily, and inefficiently compared to what human crews could do. This is a documented fact from the Apollo missions and from terrestrial comparisons.
Oh, come on. You are using 45 year old technology to predict performance 10-20 years from now? Please, at least keep your analogies within the same millennium.

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Robots have limited dexterity, mobility, dexterity, adaptability to unexpected surfaces compared even to a gloved astronaut.
In some cases yes, in other cases no. Robots are used extensively in manufacturing on Earth because they are more efficient, faster, and far more accurate in many cases.

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How big an overhead will a human mission need? More than a robotic mission certainly.
Not more, a LOT more, as has been pointed out.

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A human mars mission might have 10 times or 100 times as many people working on it. But it will be at least a thousand times as productive.
Now THAT is a totally unsubstantiated and unqualified exaggeration. As always, it depends upon the robot, the level of technology, and the application. As noted, robots are more efficient and precise in certain tasks. There is no reason to believe that decided advantage cannot be applied to exploration on Mars.

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Completely irrelevant to Mars exploration. No payload. Can only move on flat surfaces. Needs near 400 watts to run. Has an endurance for less than an hour. Such a machine is useless on Mars.
It isn’t the exact machine that is being presented, but the concepts and the obvious advancements in robotic technology. The right tool for the right job. Robots to be used on Mars will be designed to be used on Mars, incorporating the appropriate technologies.
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Old 01-December-2007, 09:36 PM
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We don't NEED a man, a woman would be fine.
You got that right!
I think it was Jacques Piccard who said something like:
"To dive to the ocean depths, to travel through celestial space, these are the things that make life worth living."
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Old 02-December-2007, 02:34 AM
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Fusing Jacques Cousteau and Jean-Luc Picard to make a generation spanning quote, very clever.

If you have seen some of my previous “200 person first mission to Mars” comments, it always includes women. That is practical, logical, and biologically reasonable.
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Old 02-December-2007, 02:40 AM
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Fusing Jacques Cousteau and Jean-Luc Picard to make a generation spanning quote, very clever.
No, silly, Jacques Piccard (Two 'c's, not one) was a famous balloonist who also designed submarines.
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Old 02-December-2007, 02:59 AM
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Old 04-December-2007, 01:29 AM
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It's okay, a lot of people probably don't know that at all, but now you can say that you do.
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Old 06-December-2007, 03:26 AM
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Of course, but all in due time.
Screw that! Let's just DO IT! We have the technology. But do we have the gumption? We could probably do it for $1011. The U.S. economy is on the order of $1013 per year. If the cost of doing it were amortized over 10 years, the total cost would only run 0.1% of U.S. GDP for 10 years. In the grand scheme of things, that's not very expensive.

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The exploration of Mars to determine the best sites for colonization is best left to the robots. It is a long ranging, but not very detailed study that is needed for this.
A priori considerations suggest that the lowest altitude spot on Mars (the Hellas Basin) would have the mildest conditions. The determination of an actual building site can be accomplished from orbit by using an old Keyhole spy satellite.

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Later on, when humans are living on Mars in colonies, THEN is the time for detailed human exploration. When people have the time to explore, instead of spending most of their time ensuring their very survival, then they can go on detailed, extensive explorations.
What time-consuming tasks are people going to have to do to ensure their survival beyond heating up some water to mix into their MRE's? Take out the trash? If there's a lot of manual labor necessary, then just bring along a few illegal aliens in order to free up the geologists' time.

Also the idea that humans are somehow "fragile" compared to machines is just wrong. How many cars are still on the road after 40 years? And have you ever seen a machine maintain or fix itself? There is no way the science that was accomplished by the Apollo project could have been done with robots. Robots can not now do the science that was accomplished on the Moon by the Apollo project. Until robots get to Bladerunner levels of capability, they will not by definition be able to do all the things humans can do. I doubt that Bladerunner-style robots will be available in 30 years, but who knows? Maybe they will. But we're supposed to hurry up and wait for 30 years to find out? That, my friend, is a councel of FUD.
  #110 (permalink)  
Old 06-December-2007, 04:18 AM
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Screw that! Let's just DO IT!
Yikes!! Take it easy, man. Have a couple shots of JD while I explain. “All in good time” meant that we shouldn’t send men to Mars until we have determined the best location. We still don’t know where water can be found and in what quantities. We don’t know the composition of the ground in any one area. If it’s flags and footprints then go home, it doesn’t matter. But if it is to be a colony, then it matters a LOT. It would be a waste of time for people to search millions of square miles of surface area for the best location. Let the robots do that.

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A priori considerations suggest that the lowest altitude spot on Mars (the Hellas Basin) would have the mildest conditions. The determination of an actual building site can be accomplished from orbit by using an old Keyhole spy satellite.
That is hardly the most significant requirement. Water, availability of certain minerals, and possible existing underground caves are more important to a colony. Except for the water, I’d say the top of Olympus Mons may be one of the best locations.

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What time-consuming tasks are people going to have to do to ensure their survival beyond heating up some water to mix into their MRE's? Take out the trash?
Again, for flag and footprints, not much at all. For starting a colony, then there would be a lot of work to do, including constructing facilities to grow food and produce oxygen.

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Also the idea that humans are somehow "fragile" compared to machines is just wrong. How many cars are still on the road after 40 years?
Strawman. It depends upon the machine, and it depends upon the application. For 24/7 operation, radiation resistance, no need for oxygen, food, water and sleep, machines are better. Here on Earth we use billions of machines to do specific tasks. We should let machines do what machines do best. That is what they are for.

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There is no way the science that was accomplished by the Apollo project could have been done with robots.
Would you care to expand upon that? Perhaps robots available at the time could not have, but current robots certainly could.

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Until robots get to Bladerunner levels of capability, they will not by definition be able to do all the things humans can do.
Another Strawman, since no one I have ever heard of suggests that they can. Robots do the repetitive tasks, the dangerous tasks, the 24 hour tasks, and a lot of really mundane tasks.
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  #111 (permalink)  
Old 06-December-2007, 04:46 AM
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If there's a lot of manual labor necessary, then just bring along a few illegal aliens in order to free up the geologists' time.
How disgustingly racist of you.
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Old 06-December-2007, 05:13 AM
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How disgustingly racist of you.
Speciesist maybe, but definitely not racist.
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Old 06-December-2007, 06:35 AM
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Yikes!! Take it easy, man. Have a couple shots of JD while I explain. “All in good time” meant that we shouldn’t send men to Mars until we have determined the best location. We still don’t know where water can be found and in what quantities.
Since water flows downhill, the most likely place to find it would be at the lowest elevation on the planet. I'm talking underground aquifers here, not flowing rivers. However, the atmospheric pressure would reduce ice sublimation, and allow water to exist in a liquid form at least for short periods. At about 1/10th of an atmosphere you would probably still need a pressure suit to walk around in though.

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[Except for the water, I’d say the top of Olympus Mons may be one of the best locations.
That's an interesting suggestion. Wouldn't it be windier than Laramie up there though?

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Would you care to expand upon that? Perhaps robots available at the time could not have, but current robots certainly could.
A robot wouldn't have found the Genesis Rock.

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Another Strawman, since no one I have ever heard of suggests that they can. Robots do the repetitive tasks, the dangerous tasks, the 24 hour tasks, and a lot of really mundane tasks.
I agree, but humans have their place too. Robots and humans can complement each other.
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Old 06-December-2007, 01:44 PM
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Robots and humans can complement each other.
"Hello, sir, your organic integument is looking quite healthy today."

"Thank you, my good 'bot, and your support rods are quite fetchingly shiny."
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Old 06-December-2007, 01:50 PM
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Speciesist maybe, but definitely not racist.
Does it really matter what you call your ignorance? I know you're certainly not the type of person that I want to have anything to do with you, even if it's only over the internet, so congratulations, you've "earned" a spot on my ignore list.

There are other people on this planet besides yourself, and how you treat them ends up being how they will treat you....so good luck to you...you'll need it.
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Old 06-December-2007, 01:53 PM
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...the idea that humans are somehow "fragile" compared to machines is just wrong...There is no way the science that was accomplished by the Apollo project could have been done with robots. Robots can not now do the science that was accomplished on the Moon by the Apollo project...
Humans are obviously far more fragile than robotic probes. That's why hostile environments such as Venus and the deepest oceans on earth are explored by robotic (not manned) vehicles:

http://nssdc.gsfc.nasa.gov/nmc/maste...o?sc=1981-110D
http://robotics.me.jhu.edu/~llw/gallery/jason_2.html

The science accomplished by Apollo could easily be done by robotic probes today, and at far lower cost.

For a hypothetical manned Mars mission 20-30 years in the future, computers and robotics would be far more advanced.

I'm not arguing humans should never go to Mars, but the specific issue of cost effectiveness. If the goal is not colonization, etc, but scientific exploration, robotic probes of the 2030s would be far more cost effective than a manned mission.

Note this is on an equal dollar basis. We can't compare a $150 billion manned mission in 2035 to (say) the $820 million Mars Exploration Rover today.

The comparison is between

(a) Equal dollars spent in the same time frame on a manned vs unmanned Mars mission, OR

(b) Estimated dollars spent on a robotic mission to equal the science return of a manned mission, both in the same timeframe.
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Old 06-December-2007, 06:27 PM
Warren Platts Warren Platts is offline
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Humans are obviously far more fragile than robotic probes. That's why hostile environments such as Venus and the deepest oceans on earth are explored by robotic (not manned) vehicles:

http://nssdc.gsfc.nasa.gov/nmc/maste...o?sc=1981-110D
http://robotics.me.jhu.edu/~llw/gallery/jason_2.html
Actually the deepest oceans were explored by humans first in 1960.


The fellow on the right is Jaques Piccard. He and U.S. Navy Lt. Don Walsch went as deep as you can go: 35,800 feet in the Marianas Trench near Guam.
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The comparison is between

(a) Equal dollars spent in the same time frame on a manned vs unmanned Mars mission, OR

(b) Estimated dollars spent on a robotic mission to equal the science return of a manned mission, both in the same timeframe.
I agree, except I would rephrase it as, given that one is willing to blow $100 billion on exploring a planet, (the Moon or Mars), which program would return the most, best science: manned or unmanned?
Also, when you say that "The science accomplished by Apollo could easily be done by robotic probes today, and at far lower cost." is an unfair comparison, because the science that could be accomplished by a second generation manned Apollo program would be an order of magnitude greater still than the original program.

The market price for a manned craft in lunar orbit is now $100 million. You have $100 billion to spend (less than the original Apollo program) on exploring the Moon. The state of the art probes are 2nd-generation versions of the rovers on Mars. What would you rather send: 100 Apollo-style lunar manned missions, or 1,000 lunar probes? If the basis for deciding is the amount of quality science returned, the clearly the former is the better option. If the basis is government jobs for the 4,000 minders it takes to watch each lunar probe, then the latter might be the better option.

Think about it this way, to match the Apollo accomplishments, you'd have to have the capability to return 100's of pounds of catalogued and photographed in context rocks. To do that is going to take more than a little Estes rocket. In other words, you'll have to send an unmanned landing craft more or less the same size and complexity as the original Eagle lunar lander. So if you're going to go to that much trouble, then why not send people as well?

You all speak of the vast complexity associated with sending people, but what was the original lander but a can whose aluminum sides weren't much thicker than a beer can, a rocket engine, and a few tanks of compressed gas, and a computer to help mind things? And having a pressurized temperature controlled space onboard a spacecraft has mechanical advantages as well. With a standard Earth temperature and pressure in the cabin, a simple store-bought laptop computer could run the whole show. So if you eliminate one layer of complexity by getting rid of humans, you add another layer of complexity and expense by having to use hardened computers that can function at extreme temperatures.

Last edited by Warren Platts; 06-December-2007 at 07:02 PM..
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Old 06-December-2007, 06:46 PM
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"Hello, sir, your organic integument is looking quite healthy today."

"Thank you, my good 'bot, and your support rods are quite fetchingly shiny."
LOL!!!!!!!!!

On a more serious note, there will always be those (I am one) who favor expanding human presence as far as we can, and those who don't see the point. It's an age old argument.
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Old 06-December-2007, 08:27 PM
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Actually the deepest oceans were explored by humans first in 1960.
That actually supports my point. Ultra-deep-diving manned submersibles capable of reaching the deepest ocean (such as the Trieste) no longer exist. Today, unmanned ROVs are used.

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What would you rather send: 100 Apollo-style lunar manned missions, or 1,000 lunar probes?
You wouldn't decide on that basis. Again, that's comparing prior small and simple unmanned probes to Apollo.

On an equal dollar basis, the comparison is between (a) Apollo or Constellation equivalent, and (b) the same dollars spent on optimally sized unmanned probes. You wouldn't necessarily use 1,000. The number and size would be a technical decision based on the science goals. It could easily be 10 large unmanned landers, each the mass of the Apollo Lunar Module, but capable of returning far more data and/or samples.

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to match the Apollo accomplishments, you'd have to have the capability to return 100's of pounds of catalogued and photographed in context rocks. To do that is going to take more than a little Estes rocket. In other words, you'll have to send an unmanned landing craft more or less the same size and complexity as the original Eagle lunar lander. So if you're going to go to that much trouble, then why not send people as well?
Again, this illustrates my point. Most of the LM payload capacity is devoted to human passengers and life support. On average, each LM returned 142 pounds of lunar samples. By contrast the non-science LM payload needed for human support was around 1,000 lbs: astronauts, space suits, food, water, air, electrical power, extra weight for man-rated redundant systems, etc. So the sample return was on average about 1/7th the size possible from a similar unmanned mission -- because of human overhead.

For a non-sample-return mission, the advantage of unmanned probes is even greater. All the payload capacity needed to get humans back can be instead spent on science payload, since the vehicle can just stay there. E.g, most of the mass (and cost) of the Apollo CM, SM, and LM ascent stage could be spent on an unmanned lander.
  #120 (permalink)  
Old 07-December-2007, 02:20 AM
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Actually the deepest oceans were explored by humans first in 1960.
That's ignoring the Beebe-Barton Bathysphere in 1935 and all of the test dives made by Piccard bathyscapes.
For gosh sakes, humans did not "begin" exploring the deep ocean by waking up one morning and diving down to the bottom of the Marianas Trench! It took baby steps.
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"If you think the LHC will create black holes, you might as well believe Hobbits are at the bottom of your garden."- Dr. Mike Inglis
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