Sample-return mission to Mars needed before manned mission.

[JonClarke]

Using and not using ISPP for a manned mission is the difference between using an all up mass in LEO of a few hundred tonnes and over a thousand tonnes. <br /><br />It also means the difference between long and long stays on the Martian surface, as the ISPP plant will also produce fuel for the vehices, power for the hab, water and oxygen for the crew. Redundancy is built into the mission archiecture much more efficiently than with bring it all from earth missions. Redundancy with a non ISPP mission pushes mission mass in LEO to several thousand tonnes.<br /><br />Without ISPP/ISRU it's unlikely that crewed landings will be practical. That why just about every US Mars mission study for the last 14 years has included some form of it as an essential technology.<br /><br />Jon<br /> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[dobbins]

The needs of a crewed mission have exactly zilch to do with a simple sample return mission. A sample return mission is of interest to other people besides the advocates of manned flight to Mars and attempting to cram a fuel test that will endanger a sample return down their throats is only going to create more opponents to a manned mission to Mars.<br /><br />

 

[JonClarke]

So you are advocating only minimalist MSR missions? If you don't like the complexity of ISPP then you presumably don't want the complexity of MOR either. Are you aware that such missions would return a few tens of grams of sample?<br /><br />In my view such a mission is better than nothing, but I would prefer a bit more material to work on, the several hundreds of grams that MOR profiles would allow, and or better the several kg that ISPP makes possible.<br /><br />This is quite independent of whether or not there will be a future human mission. I agree that MSR can be justified on its own merits. However the reasons become even more compelling if it is a precursor mission to the first human landings.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[dobbins]

What I'm advocating is not letting the agenda of the people that want to rush to Mars to get in the way of a mission that has implications beyond the agenda of one segment of the space community.<br /><br />

 

[JonClarke]

Who here is advocating rushing to Mars?<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[pathfinder_01]

I am confused here. Why would you attempt to make propellant on the 1 st sample return mission to mars? Sure that would be a great gain in theory, but why take the risk when at the moment there are zero grams of material from mars waiting to be analyzed on earth. <br /><br /> I can see a dual mission where a probe caring an experiment to generate fuel on mars as well as collect a sample to send back to earth. I can not see anyone funding a probe that must make fuel on mars to return it’s sample to earth. Too risky. <br /><br />All you would need is for some dust to clog up the processing equipment and instead of a few hundred grams of precious material to analyze you get nothing. In addition there could be all sorts of other ways to do this mission with less risk. More cost and less capability perhaps but at least you WOULD have a hand full of Martian dirt giving you confidence in your ability to return something from a mars. <br /><br />If you must test something then perhaps you could test the engine using methane carried from earth since you would need an engine anyway and currently no engine has been tested at mars. <br /><br />Me personally, I would go with a mission that landed a lander and put the return ship in orbit and just depended on the lander lauching the samples into mars orbit. <br />

 

[wdobner]

Well, why don't we try to find a way that the sample return vehicle could come into low earth orbit, dock with a manuvering vehicle, and then have that vehicle fly to the ISS for at least the initial investigations into the sample. That way the sample stays nicely away from all 6 billion of us, and any dangers posed by the sample are exposed to 3 to 6 people on the ISS. This way we get a detailed investigation of what is in a Martian soil sample, the nuts who fear the dirt will kill us all don't have it closer than a few hundred miles, and hopefully the ISS gets a slight upgrade and a mission which even the most virulent anti-ISS people can support.

 

[dobbins]

You are making an assumption that Luddites will react logically instead of emotionally. They will quickly come up with fear stories ranging from astronauts bring a plague back from the ISS to wild tales of the population being wiped out when the ISS crashes "like Skylab".<br /><br />

 

[nyarlathotep]

This is ludicrous. <br /><br />Earth sweeps up several hundred kilograms of meteorites ejected from Mars every year. If there was anything nasty on Mars, we've already been contaminated with it.

 

[josh_simonson]

Well, meteorites that spend between 1 and 1 million years in the harsh evironment of space, then fall to earth in a several thousand degree fireball...

 

[lclark2074]

I agree first get srm and do some tests with a propelent lab and bring back a small of the product you make like a gram of the fule you make. The rest of it gose into mars atmasphere.<br />What i like to see is a class of rovers so the r&d cane be spred over the program. And more rovers Means you get more since. When you make classes of rovers all you chang sencers so you don't redisine the hole thing <div class="Discussion_UserSignature"> </div>

 

[JonClarke]

Hi pathfinder<br /><br />Everything about a MSR mission has risk. Landing is risky, so is trying to obtain the sample, earth return launch, possible rendezvous in Mars orbit, injection to earth transfer orbit, entry and landing.<br /><br />ISPP eliminates one type of risk - MOR, proosed by most MSR missions - in exchange for another, ISPP. It is not evident to me that ISPP is a greater risk, as it would have been extensively tested under simulated conditions on earth (probably harsher than those actually encountered) and proably demonstrated as a secondary payload of an earlier mission. The advantage is of ISPP is that it allows a much greater payload to be returned to earth, much greater than can be achieved using MOR.<br /><br />Dust can be excluded by filters, the amount of dust in the martian atmosphere and its size distribution is quite well known. Filters can be designed that will not clog in the time required or pass a signbificant amount of dust down the processing stream. Alternatively you can liquify the atmospheric CO2 in a closed environment and then let most of it boil off. the dust stays in the liquid and can be dumped as a slurry, he gas that is boiled off goes downstream. If very high purity is needed then both processes could operate sequentially. These are the sort of issues that would be addressed before you sent an ISPP plant to Mars and could easily be tested on earth in a simulation chamber.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[josh_simonson]

Shoot, a semi-permeable membrane would easilly eliminate all dust, though you'd probably want a pre-filter. <br /><br />It's alot easier than the problem of people tromping dust in/out of a spacecraft.

 

[JonClarke]

Indeed it is, although even that is a manageable issue.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[scottb50]

Until we have people on Mars the data we get is limited. A person could do more in an hour than robotic testing or return missions could do. It seem pretty obvious that there is little or no out-right danger involved, and the fine dusts will present a problem, but that can be controlled using current expertise. Whether or not small quantities are a problem will remain until we test it anyway.<br /><br />I see absolutely no reason we couldn't start tomorrow, or even today. <br /><br />If the researchers bring back samples, that's fine, until we get people there we know little more than nothing. <div class="Discussion_UserSignature"> </div>