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But a human mission IS a one shot venture too
I suppose I should have done a better job of defining what I meant by "one shot". A probe has a very limited set of missions it can perform and really cannot stray outside of that narrow box.
Humans on the other hand can improvise on the spot according to conditions. This is not to mention that the same software (their brains) can be used for multiple tasks beyond having to become active once they reach Mars' surface.
The closest probes can get to this is by adding on remote control devices. But this is hampered from full effect by the great distances between Mars and Earth. It is not realtime at all. And even with this it is more about changing locational priorities than mission priorities.
I stand by my assessment that there can be many experiments conducted en route, and in orbit, that we end up having much more data possible before hitting the surface.
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The problem is that a human mission may carry more equipment, but how much more? I'll venture not much since food, water, multiple redundancy of systems etc is necessarily going to take up the bulk of the mass.
Obviously the human mission is going to have to bring food and water (and air). That's going to be THE MAJOR added expense, in addition to the greater amount of fuel.
But this is essentially saying "fuel source" for the human hardware. So yeah, humans consume a less concentrated and convenient fuel, and so it will take up more space and use up more fuel. The question becomes for that same fuel and space, will the humans make more of it than probes?
Well one great thing is that unlike the probes we can create a selfsustaining fuel cycle for humans. Thus humans can actually have a longer life and not need to be kept asleep during the voyage, or for portions of time on surface. Also, once on the surface the humans can use their fuel more efficiently as there does not need to be downtime (yet fuel continues to be consumed) waiting for commands or when not in a correct position due to rotation.
And humans can clean and repair equipment for reuse. This is not truly possible for a probe... or true only in a very limited way. They can also (if prepared with a small machine shop) make their own equipment as needed.
Given the same amount of equipment as a single probe, humans have the potential to run many more experiments, and without the spacial constraints of a probe. If one must swap existing probe equipment for the added needs of the human hardware, I agree one is not better off. But I think that is a bit of a strawman, as that would be a silly idea to start with, and is not anything close to what I would recommend.
I am arguing for taking a bit more extra equipment than a single probe, in addition to the regular probe equipment and the necessities for a human crew. The human crew will come off better with the fuel they are given.
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The best that could be said is that they could perform the same task to more samples, but so what? They are geographically limited, anyway.
This is not true at all. They can walk further than any probe can crawl, and that's not to mention the could use tracked vehicles to move around even faster (if they wanted to add the weight of a rover). Of course for much less weight they could also fly small "probettes" (like the small military drones we have now) around from the safety of their capsule to other sites. This is much different than our current probes as it would allow real time control and spread over a much greater area.
For greater effect (and smaller weight) they could use balloon drones. I think they might even be able to get the gas from components of the martian soil so they wouldn't have to carry added weight on the flight.
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Beyond that, unless the task involves something pretty trivial like hitting something with a hammer they are going to be pretty much impotent.
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Like I said, I would give them the same equipment. But saying hitting something with a hammer is trivial... harrumph! A lot of good geological work is done hands on, and cannot be done with probes (unless I am wrong and they have the nimbleness to create a slide for miscroscopic analysis).
Let's replace that hammer with a small spade shovel, and you just beat any single probe. Humans can DIG. They can dig faster and farther than a probe and choose a wider scattering of samples. This may not be true on ice planets (where a probe can melt to depth), but is certainly true on solid rock planets.
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That's 366 successful probes (of 1,100 sent), each potentially performing several tasks all over the Martian surface, whereas the humans are limited to within a couple of miles of their base.
I will totally accept your figures and even put myself at greater disadvantage by assuming humans will get better and so less missions fail over time (not to mention I will pretend like the price won't go up for each probe). So let's say for 30M we get 750 successful Mars probes. That means 750 different spots on Mars, analyzed for X amount of samples, and at depths of inches to a few feet of soil.
Oh yeah, I'll also forget that these 1100 missions flown (at average 3-5 years to go from planning to working on the surface) will be over the course of some 100's of years (at best). We will pretend that we flew 1100 all at once.
Now for the manned space mission, while we would potentially only have one Mars Base, it would be able to accumulate more raw data for the area within its reach, then for any of the 750 probes. We will be able to move DOWN and AROUND which is more valuable to real geology than OVER and SLIGHTLY BENEATH.
Given the correct equipment they could set up a small coring station and get a real well log.
They will also not be at the mercy of rocks and range, in order to get proper samples to describe the regional geology. With probes we are limited to what we can get.
Two astronauts could even do some pretty decent survey work. This is not really possible with probes (unless you get a couple running in tandem).
And as mentioned, the crew can conduct a variety of open space experiments during the flight there and back. Even if lost before hitting the surface, we should get some good data in flight (which is what we never get from failed probes).
With the addition of drones, or perhaps a vehicle, or an orbital station (like we had on moon missions) the range of a manned mars mission could be quite similar to 10 or more of those successful probe missions, yet yield more comprehensive data within that range.
I understand that in pure dollar amounts we can send more missions, and more missions makes it sound like more quality... but I do not believe quantity equals quality at all. If I was a geologist trying to survey the grand canyon, I would rather pay for a team of geologists (even two), than toss 1000 rovers at it from Chicago... especially with no realtime connection to the rovers. The quality would not be the same.
And I will now bring up the time factor. We will get more info in that one 3-5 year manned Mars mission than any 10-100 probes which would take over 30-50 years (and that's being lenient).
As far as costs go, I do wonder at how much intercontinental missions (like Columbus) cost to nations back in their day. From what I understand it was quite a bit. I am unsure if it is comparable, but I'd like to know.
Then I look at what we pay for stealth bombers and sdi and oh let's say the new Bears stadium and I think, why not move some money over for a manned mission? We could always do one or two, and just see if it bears the fruit which is promised. If not, go back to probes.
I think we are being overly pessimistic in dismissing the manned potential, especially when cost is the main issue (11B is not much on a gov't level). We could have paid for a couple of Mars missions for the price of Iraq, and we'd have lost less people and been just as safer (though I will admit the Iraqis would not have the opportunity to be ruled by Chalabi).
And in conclusion... what about the Moon? Even if I grant that probes may be the best bet for Mars for a while, why not get back to the moon and setup shop?
I will note that it was announced today that Hubble will be coming down in 2006-8. Moon telescopes would have longer lives and even better quality.
Drink a pint, mull it over, and get back to me later.
holmes
"...what a fool believes he sees, no wise man has the power to reason away.."(D. Bros)
™ Version 4.2
