Printable Version of Topic

Posted by: dilo Apr 1 2005, 09:19 PM

This mosaic of 4 Panoramic frames from Sol442 show a strong increase in density of rocks, even big ones! Don't know if could be an issue for further movements toward the hill top?
http://img93.exs.cx/my.php?loc=img93&image=sol442pancammosaic8eh.jpg

Posted by: Sunspot Apr 1 2005, 10:18 PM

I remember thinking the same when Spirit was driving up to the rim of Bonneville Crater....

Posted by: Tman Apr 2 2005, 08:20 AM

I have also some reservations. This spiky high rocks are so numerous as never before on Spirit's way.

For comparison:

Sol065 at the side of Bonneville:
http://marsrovers.jpl.nasa.gov/gallery/all/2/n/065/2N132143294EFF1600P1835L0M1.JPG

Sol106 on the rim of Missoula:
http://marsrovers.jpl.nasa.gov/gallery/all/2/n/106/2N135770915EFF3100P1846R0M1.JPG

Sol132 on the plane of Gusev:
http://marsrovers.jpl.nasa.gov/gallery/all/2/n/132/2N138080715EFF5200P1846R0M1.JPG

Sol381 at the side of Husband Hill:
http://marsrovers.jpl.nasa.gov/gallery/all/2/n/381/2N160194962EFFA2IOP1916R0M1.JPG

Even I guess Spirit can't drive over. In this case we have to go another way to the top of the (an) Hill. We could drive through the Tennessee Valley. Then at its end it gives divers options to go higher.

Posted by: ElkGroveDan Apr 2 2005, 04:15 PM

One of the things to keep in mind, especially with the pancam is that there is a certain amount of optical foreshortening in these images (can anyone calculate the relative focal length on a lone pancam shot compared to a 35mm slr? I'm guessing it's the equivalent to 60-80mm). The rocks appear closer together and hence denser in number than is actually the case. Spend a lot of time viewing the analglyphs (as I did in the first 150 sols) and the effect will become apparent.

Granted that navigation must be getting more complex, but I'm guessing there is still enough room between the larger obstacles to maneuver for a while longer.

Posted by: djellison Apr 2 2005, 05:16 PM

105mm I believe.

Doug

Posted by: Jeff7 Apr 2 2005, 05:35 PM

And remember too, the rover was designed to be able to traverse obstacles 2x the diameter of the wheels (wheel diameter = 25cm). Might be a bumpy ride, but the rover shouldn't tip over or get stuck. Those wheels have a lot of torque too.

Posted by: Buck Galaxy Apr 3 2005, 06:28 AM

All these sharp rocks will make designing a safe Mars suit more difficult. Suit punctures from falling or even just walking could be a serious problem for future human explorers.

Posted by: BruceMoomaw Apr 3 2005, 12:39 PM

EVA suits present a severe problem for manned Mars exploration in any case, given the fact that the planet's surface gravity is over twice that of the Moon -- and that we want to absolute minimize the extent to which leakage of human atmosphere contaminates Mars with Earth germs. One interesting point made at the first meeting of NASA's Mars Strategic Roadmap group is that, for these reasons, manned Mars exploration will be something radically different from what we're used to from Apollo -- it will consist very largely of humans running robots by remote control from the central base or from the cabins of their pressurized rovers, with suited-up EVAs limited to the absolute minimum necessary.

Posted by: ElkGroveDan Apr 3 2005, 03:17 PM

Yes basalt and human shoes or clothing do not get along well. Places where there are miles of fractured basalt will do nasty things to modern hiking boots. Southern Idaho, or the cinder cones in California's Owens Valley come to mind. I once had the sole of a leather boot come completely off after a day of hiking near "Craters of the Moon" national monument in Idaho.

On the other hand, I would bet that if we had to make a decision where to land an astronaut tommorrow, the plains of Meridiani would be higher on the list than the rocky hills of Gusev.

Posted by: dilo Apr 3 2005, 05:11 PM

Now it seems to me that Spirit is avoiding the dense rock fields... :
http://img223.exs.cx/my.php?loc=img223&image=sol443pan11lh.jpg
In the meantime, now we see again the North Gusev rim (I didn't for a while...); increased transparency or only favorable light conditions?
http://img223.exs.cx/my.php?loc=img223&image=gusevnorth3gg.jpg
(the top blue portion was elaborated in order to have some smoothing and huge contrast increase).

Posted by: Sunspot Apr 3 2005, 06:37 PM

Which sol are those images of Spirit's tracks from?

......exploratorium site down again?

Posted by: Buck Galaxy Apr 4 2005, 02:22 AM

"...with suited-up EVAs limited to the absolute minimum necessary."

A mandatory EVA being the first human setting foot on Mars of course. :-) I would think the entire crew would get a chance to do EVAs at least once for symbolic sake alone.

Posted by: dilo Apr 4 2005, 04:27 AM

SOL443. I taken them from exploratorium yesterday but now you can find same Pancam images also in MER site: http://marsrovers.jpl.nasa.gov/gallery/all/spirit_p443.html



About EVA activity, it seems to me foolish send humans on Mars surface and then use robots...; using this philospohy, in order to reduce risk, is even better to remote control a robot from Mars orbit!

Posted by: BruceMoomaw Apr 4 2005, 06:40 AM

"About EVA activity, it seems to me foolish to send humans onto Mars' surface and then use robots... Using this philosophy, in order to reduce risk, it's even better to remote-control a robot from Mars orbit!"

I agree enthusiastically with Dilo. In fact, that possibility has been repeatedly discussed, and it too was mentioned by some of the members of the Roadmap Committee. According to an Op-Ed that Donald Robertson wrote in "Space News" several years ago, it's the position toward which a rapidly growing segment of the planetary science community is also leaning. If the US insists on actually landing humans on Mars just for PR purposes even though that act will run a serious risk of biocontaminating the planet, it's likely to run into very serious opposition from the science community.

I think of this as the "Martian Catch-22": the only scientific discovery which could justify something as expensive as a manned expedition to Mars is the discovery of evidence of present or past life, but manned landings will disastrously contaminate the very thing they were sent there to study!

Posted by: Buck Galaxy Apr 4 2005, 07:36 AM

So why not set aside 99% of Mars for robotic-only exploration but build a few bases in one small section of Mars? Surely a base or two won't contaminate an entire planet? Especially if they are very careful not to contaminate.

An aside, I HATE the word "contaminate" when refering to bring life to other worlds.
I can see the point when there is a question if there is life somewhere or not and the need to study some alien microbes without any earth bugs getting in the mix etc etc, but I think it is ultimately humanity's responsiblility and calling to spread life throughout the Solar System and Galaxy. Not just microbes but advanced life.
What greater purpose could our existence serve?

Posted by: djellison Apr 4 2005, 07:42 AM

You can detect the radiation from Chernobyl in plants the world over. Ditto certain volcanic events etc. Simply to maintain the validity in studying martian life - we have to be very very carefull with it. If life is there, then like our own it is probably a delicate thing that we need to be sensitive towards. How will history judge us if we render all species, if any, on the first planet we visit outside our own, extinct?

Doug

Posted by: Tman Apr 4 2005, 08:38 AM

What purpose could our existence serve?

The first step for a responsibility to spread life is to serve life on Earth - the reacher the biodiversity the better. We need still our only source for a long long time. We must also pool together our resources more intelligent as today for that.

My guess is that we cannot go away seriously until we have managed our home right In order to go away we need a lot of resources. And this resources are only be available on an Earth that is full calmness, love and excessive power...

Posted by: paxdan Apr 4 2005, 10:28 AM

Interesting article from NewScientist regarding the biological component of the aerosols in the http://www.newscientist.com/article.ns?id=dn7217

From the Article:
Air samples collected by Jaenicke from over Germany, Siberia, the Amazon rainforest, Greenland and remote oceans found that tiny particles of organic detritus, much of it in the form of biological cells, make up about 25% of the atmospheric aerosol [...] That is twenty times previous estimates and similar in scale to mineral dust.

The article goes on to say that "around a billion tonnes of bio-aerosols enter the [earths] atmosphere every year". While I realise any manned landing on mars is not going to generate this kind of quantity and that the strongly reactive atmosphere/UV would break down organic molecule i think this indiactes two things:

First if there is life on mars, searching for bio-aerosols is a good place to start. Sample reurn of the martian aerosols via a low altitutde atmosphere pass would be an excellent place to start. NASA already has experience at this kind of particulate collection strategy (Genesis and Star Dust) and experience at atmospheric passes, i.e. aerobraking Mars Global Surveyor and Mars Odyssey. A sample return of this nature would be a heck of a lot cheaper and far simpler than a surface reurn mission. Call it an engineering demonstrator of the return to earth section of a more complex (lander, collection, return to orbit, martian orbit rendevous, RTE) surface return strategy.

Second, life detection on planets orbiting other stars has definitely been given a boost by this discovery.

Posted by: BruceMoomaw Apr 6 2005, 12:56 PM

Buck Galaxy, April 4: "So why not set aside 99% of Mars for robotic-only exploration but build a few bases in one small section of Mars? Surely a base or two won't contaminate an entire planet? Especially if they are very careful not to contaminate."

This suggestion has been made -- astrobiologist Frieda Horneck recently proposed setting up a series of very big protected-environment "natural parks" on Mars, in which only sterilized devices would be allowed to explore -- but the risk remains that terrestrial germs would spread gradually across the entire planet throughout any water table that Mars possesses. The spread might be slow and incremental, but it would still happen. (It will happen a lot quicker on Europa, of course, if we manage to contaminate that world's unified subsurface ocean -- which is why NASA's scientific advisory group has concluded that the sterilization of Europan spacecraft is even more important than that of Martian spacecraft.)


"An aside, I HATE the word 'contaminate when referring to bring life to other worlds. I can see the point when there is a question if there is life somewhere or not and the need to study some alien microbes without any Earth bugs getting in the mix etc etc, but I think it is ultimately humanity's responsiblility and calling to spread life throughout the Solar System and Galaxy. Not just microbes but advanced life. What greater purpose could our existence serve?"

I myself have absolutely no objection to spreading Earth life to lifeless worlds -- but the whole purpose of looking for alien microbial life is to learn new and important scientific things. How can we possibly do that if we contaminate every supply of it we discover as soon as we start investigating it, which we definitely will do if we insist on putting people on the spot there rather than doing our sample-collecting with sterilizable unmanned vehicles (possibly controlled by humans in Mars orbit)?

Posted by: BruceMoomaw Apr 6 2005, 01:03 PM

Paxdan: "...If there is life on Mars, searching for bio-aerosols is a good place to start. Sample return of Martian aerosols via a low altitude atmospheric pass would be an excellent place to start. NASA already has experience at this kind of particulate collection strategy (Genesis and Stardust) and experience at atmospheric passes, i.e. aerobraking Mars Global Surveyor and Mars Odyssey. A sample return of this nature would be a heck of a lot cheaper and far simpler than a surface reurn mission. Call it an engineering demonstrator of the return-to-Earth section of a more complex (lander, collection, return to orbit, Martian orbit rendevous, RTE) surface return strategy."

This is exactly the design of "SCIM", which was one of the four finalists for the last Mars Scout selection. It could be very scientifically useful, but let's not overestimate its usefulness in Martian astrobiology -- which would probably be nil. First, Martian atmospheric dust and gas has been exposed for long periods to solar UV, and probably to the traces of H2O2 oxidant produced in Mars' atmosphere by that UV -- which are very likely to quickly break down any complex organics in them. Second, a SCIM-like sample collector that plows through the upper atmosphere at about 20,000 km/hour will heat any dust particles or gas molecules it scoops up in its aerogel collectors to several hundred degrees, finishing the job of not only sterilizing them but breaking down any complex organics into far simpler compounds that would probably be hopelessly uninformative scientifically. (For this reason, by the way, the sample that SCIM returns -- if it ever flies -- would not need to undergo sterilization protocols on Earth.)

Posted by: Chmee Apr 6 2005, 05:15 PM

I think not allowing human EVA's is a bit paranoid, at least on the grounds of biotic contamination. We are talking about an extremely harsh environment (much worse than Antartica) where there is absolutely no evidence of current (or even past) life. Going all the way to Mars to remote pilot robots does not make sense; we can do that from here.

Mars is not isolated and never has been. There has been an exchange of rocks (in the form of meteorites from large asteroid impacts) between the planets since the formation of the Solar System, so if any "contamination" happened it occured long ago. This is not even counting the number of probes that have already landed on its surface.

Comparing the impact of a scientific research station to a nuclear reactor meltdown (like Chernobyl) is not a fair comparison. The small amount of possible contaminates from a manned station is not even a several orders of magnatute like that from that of a large fission reactor.

If life exists, it is probably buried very deep and will be very difficult to find, thus requiring people to be there.

Dont get me wrong, I hope we find life there on Mars. Let's just not be so afraid of possible (non-existent) threat of contamination that we never go there.

BTW wasn't this same debate carried out in Kim Stanley Robinson's books? Reds vs Greens?

Posted by: Mongo Apr 6 2005, 08:30 PM

Considering the huge cost of a manned Mars program, would it not be safer (from the standpoint of avoiding biocontamination, as well as avoiding human risk), as well as more scientifically productive, to put that money into developing autonomous robotics?

An Asimov-level robot could spend years on the surface of Mars with no need for resupply, and no additional risk of biocontamination--plus have its senses optimised for geology, etc.

I agree that the current robots are a long way from 'I, Robot', but a few tens of billions of dollars on AI/robotics development could just make a difference in robotic capabilities--and, in my opinion, tip the scales firmly in favor of robotic exploration.

Bill

Posted by: Gray Apr 8 2005, 01:07 PM

Robert Ballard has an interesting story about his undersea exploration which may be apropos to this conversation. The Alvin is only big enough for two people plus the pilot, and has only small porthole to view the outside. Back in the 1970's Ballard installed a CCD camera on the outside of the vessel. On one dive he was accompanied by a man who was an expert in the giant worms that lived by the deep sea vents. He let the "worm guy" look out the porthole, since that was the purpose of the dive, and Ballard operated the CCD. Part-way through the dive Ballard realized that the other guy was watching the TV screen over his shoulder. When Ballard asked him why he was looking at the TV screen and not out the porthole, the man replied, "The view is better." At that point Ballard realized that it was much more effiecient to conduct all of his undersea research using unmanned submersibles.

Posted by: tedstryk Apr 8 2005, 02:23 PM

[quote=Buck Galaxy,Apr 4 2005, 07:36 AM][quote=BruceMoomaw,Apr 4 2005, 06:40 AM]"About EVA activity, it seems to me foolish to send humans onto Mars' surface and then use robots... Using this philosophy, in order to reduce risk, it's even better to remote-control a robot from Mars orbit!"

I agree enthusiastically with Dilo. In fact, that possibility has been repeatedly discussed, and it too was mentioned by some of the members of the Roadmap Committee. According to an Op-Ed that Donald Robertson wrote in "Space News" several years ago, it's the position toward which a rapidly growing segment of the planetary science community is also leaning. If the US insists on actually landing humans on Mars just for PR purposes even though that act will run a serious risk of biocontaminating the planet, it's likely to run into very serious opposition from the science community.

I think of this as the "Martian Catch-22": the only scientific discovery which could justify something as expensive as a manned expedition to Mars is the discovery of evidence of present or past life, but manned landings will disastrously contaminate the very thing they were sent there to study!

[/quote]

Well, yes, but if we did it now, there is a chance we would destroy our chances of ever finding if Mars had its own life. Also, it would hurt our chances of discovering whether or not Earth life was transmitted via meteorites. We would never know if it was brought naturally or artificially. And it would be a shame to find the remnants of Martian microbes that our microbes killed off before we had a chance to study them.

Posted by: wyogold Apr 9 2005, 05:17 AM

I think you are missing an important point about driving/controling robots at mars compared to at earth. It takes a great amount of effort to send the signal from earth to mars plus you are limited to bandwidth,time,position of the planets. The delay in signal is also a huge factor. Its not like you can just pick up a joystick here on earth and drive the rover around. Its a give the command, wait half an hour and see what happens, repeat. If you are on mars you have real time control of the rovers/robots. I do think that we need eva after finding a good area with the rovers. I would do this on the premise that the amount of data processing a human can do is incompatible to a remotely controlled robot. Plus if you put somebody there that has a large knowledge base (of geology or such). They will be able to see things that will be of interest that might be missed by a remote camera on a rover. One instance of this is the presumably huge dust devil that went by spirit which was unknown until the moc photos reveled the track. A human would have seen and document that. To me the amount of work a human does in a day would take a rover several weeks if not months to complete and the human results would be vastly superior.

scott

Posted by: Bill Harris Apr 9 2005, 07:34 AM

To have humans _on_ Mars is more than a PR stunt (athough one might argue that the current US Administration's announcement of this goal is just that); in a larger sense, this is the human destiny.

But having a spacious and well-equipped manned orbiter _at_ Mars with multiple Rovers communicating with the orbiter in real-time via geocentric relay satellites is the reasonable path to travel. Samples could be delivered to the orbiting lab facility using return-to-orbit samplers.

A living, breathing observer on Mars would be a wonderful event, but the environmental overhead of keeping the observer in that state would be tremendous at Mars' distance.

--Bill

Posted by: dvandorn Apr 9 2005, 07:58 AM

Actually, no. Keeping a human crew alive and well is probably easier on the surface than in orbit. At least, it's easier assuming you'll be able to use Martian resources to support the manned crew.

For example, if there *is* a lot of ice easily available to relatively simple equipment, a crew can use Martian water for drinking, washing and food cultivation, and (through electrolysis) to provide oxygen for breathing. They can also use Martian water and elements in Martian rocks to make rocket fuel to get them back home.

Lugging all the Martian resources you want to use all the way up to Mars orbit will be more difficult and probably a good deal more expensive. Most expensive of all is bringing everything you need from Earth.

Biocontamination issues aside, a maned Mars landing is probably going to be easier and cheaper than a manned orbital mission.

-the other Doug

Posted by: Jeff7 Apr 9 2005, 08:40 AM

One thing though - to convert the ice to usable water for cultivation and oxygen, you're going to need a lot of equipment. We're talking about like maybe a convoy of ships to Mars, all capable of landing and deploying in fairly short order, because the astronauts don't want to die of dehydration while trying to get their ice melters active. And power sources might be a problem - sure there's solar power, but one good dust storm could very quickly cause serious problems.
And, the best spots for ice are at the poles - not much solar power available there, on a planet already farther away from the sun than we are.

Humans are just too fragile and expensive (in terms of raw resources) to keep alive during a mission like this, at least considering the possible payoffs.

Once we figure out how to make a sustainable space station, then we might be able to put something in orbit around Mars, and control a rover from there. The problems with the ISS aren't exactly a good sign for this either - you can't keep sending new supplies to a space station millions of miles away.

Geez, I'm quite the optimist here, eh?

Posted by: Mode5 Apr 9 2005, 09:20 AM

A spacecraft in orbit with humans on board will be able to accomplish the tasks of control. They will have the ability to upload/download and store data for return to Earth. Obtaining samples would be an automated process without the need for humans. The collection of items will take longer during a mission without a human's presence. Robots can still give us what we want.

The problems with landing on Mars are immense for humans. There will always be a slight risk that they will not land properly or achieve a return orbit to Earth. A mission concentrating on the deployment/control of robots and satellites from an orbiting vessel has many advantages. It would be safer. It could give us a platform for future missions. Humans that land on Mars will need to take all biological waste back with them. They will need a clean room and a decontimation room to transit in and out of the lander. That will take a fair amount of time. We don't want to bring any uncontrolled Mars specimens back to Earth just yet.

I hope we go slow in a plodding course forward. Step by step. Keep the general public, who are not as fascinated by space wanting more and more. I don't want to see a repeat of the apathy during the Apollo missions. I believe Apollo 17 was the best mission from a scientific standpoint, unfortunately it was also the last. Apollo tells us that science alone will not keep the exploration going. Eventually we will have to land humans on Mars. I want a long term self-sustaining settlement also but that is many decades off. I hope I live to see it.

I believe an orbit-only mission would cut the R and D time considerably. Ultimately using robots will give us more science and at an earlier date than if we land humans on the surface.

Posted by: cIclops Apr 9 2005, 10:43 AM

The difference between remote operations from Earth or Martian orbit is only significant in terms of time delay and that is only important during robot movement operations. Taking longer to move a robot from site to site, or positioning a sensor or manipulator, is almost insignificant compared with the enormous cost of sustaining people in Martian orbit. Having spent all those resources putting people into orbit, the incremental cost of landing them on surface is small compared with the benefits of having the most sophisticated "robots" in the known universe on the surface conducting exploration and scientific studies. The question is not whether to put people on the surface or in orbit, it's whether to send people to the surface.

Posted by: TheChemist Apr 9 2005, 03:11 PM

Todays PanCam depository on Exploratorium consists of rock portraits.

http://qt.exploratorium.edu/mars/spirit/pancam/2005-04-09/

Posted by: dilo Apr 9 2005, 09:00 PM

Very intriguing gallery...
http://img50.exs.cx/my.php?loc=img50&image=rockgallery9sy.jpg
especially the left image on 2nd row, with truncated rock and apparently white material on one side of rocks to the right!

Posted by: Bill Harris Apr 10 2005, 10:16 AM

The mining and processing operations you suggest may be appropriate for colonization many decades down the road, but for the immediate research and exploration missions, an orbiting "mother ship with robotic drones" is the most practical approach. Jeff7, Mode5 and cIclops answered well so I won't repeat...

Remember, the Martians tried the direct landing and exploration gig back in the 30's and ended up D E A D. Fortunately, we on Earth didn't get wiped out because biocontamination hadn't been invented yet...

--Bill

Posted by: BruceMoomaw Apr 10 2005, 02:38 PM

Getting back for a moment to whether humans should be put on the surface of Mars: if it wasn't for the biocontamination issue, the argument for going that small remaining distance if you've already put them into Mars orbit would be extremely strong, thanks to the fact that Mars (unlike the Moon) has easily accessible resources (atmosphere and ground ice) that can be used to sustain a surface crew but not an orbiting crew.

But the biocontamination argument against it is still extremely strong. If one argues that Mars is already contaminated by terrestrial organisms transferred from Earth to Mars via meteorite, then the main scientific argument for running up the huge expense of sending humans to Mars promptly collapses too. And if one argues that it's unlikely that manned crews would contaminate more than a very small slice of Mars: the problem is that they WILL, at an absolute minimum, seriously contaminate every single local part of the planet that they actually try to examine scientifically. For all these reasons -- more than the expense of the expedition, although the latter is also a serious problem -- I think it will be a very long time before we send humans to the surface of Mars.

By the way, keep in mind that if you're going to adopt the alternative of just putting a crew into orbit around Mars and having them teleoperate surface-exploration robots without that maddening radio time lag, you can explore Venus in exactly the same way. And it's closer (if less scientifically interesting, and more exposed to solar particle radiation and X-rays...)

Posted by: Jeff7 Apr 10 2005, 02:43 PM

Mention of a crewed orbiter around Venus brought up one other issue - venturing outside of Earth's magnetic field. Missions to the moon were lucky - a good solar flare could kill off an entire crew.
If I remember right, the October flare from a year or two ago fried an instrument on one of the Mars orbiters. Imagine the radiation dose closer to the sun - and Venus has no magnetic field, so there is no safe haven there.

Posted by: cIclops Apr 10 2005, 02:54 PM

And what exactly is the basis for assuming this? That earth DNA will somehow jump into Martian DNA (if it exists) and modify it to such an extent that it can't be detected? Or that earth organisms will suddenly thrive in the harsh Martian environment, far harsher than any on Earth, and destroy all Martian life? Or that Redpeace have just issued a press release?

Posted by: Mode5 Apr 10 2005, 11:15 PM

Great pics Dilo, thank you for posting. The 3rd one down on the right is my favorite. The split in the rock with the inner surface exposted is begging for a close-up.

Posted by: Mode5 Apr 11 2005, 12:48 AM

The first point below explains the need to keep things in as pristine a state as possible.

http://www.cosparhq.org/scistr/PPPolicy.htm

Sample Return Missions from Mars

Category V. The Earth return mission is classified, “Restricted Earth return.”

• Unless specifically exempted, the outbound leg of the mission shall meet Category IVb requirements. This provision is intended to avoid “false positive” indications in a life-detection and hazard-determination protocol, or in the search for life in the sample after it is returned. A “false positive” could prevent distribution of the sample from containment and could lead to unnecessary increased rigor in the requirements for all later Mars missions.

• Unless the sample to be returned is subjected to an accepted and approved sterilization process, the sample container must be sealed after sample acquisition, and a redundant, fail-safe containment with a method for verification of its operation before Earth-return shall be required. For unsterilized samples, the integrity of the flight containment system shall be maintained until the sample is transferred to containment in an appropriate receiving facility.

• The mission and the spacecraft design must provide a method to “break the chain of contact” with Mars. No uncontained hardware that contacted Mars, directly or indirectly, shall be returned to Earth. Isolation of such hardware from the Mars environment shall be provided during sample container loading into the containment system, launch from Mars, and any in-flight transfer operations required by the mission.

• Reviews and approval of the continuation of the flight mission shall be required at three stages: 1) prior to launch from Earth; 2) prior to leaving Mars for return to Earth; and 3) prior to commitment to Earth re-entry.

• For unsterilized samples returned to Earth, a program of life detection and biohazard testing, or a proven sterilization process, shall be undertaken as an absolute precondition for the controlled distribution of any portion of the sample.


Edit:
"you can explore Venus in exactly the same way." -BruceMoomaw
Yes, exactly. The same technology could be used for any number of locations. It's well worth getting this done now. The return on investment would be used as a way to continue further missions. DARPA and the US military are going in this direction(remote robotics). We can piggyback their research and vice-versa. I think this is one of the main reasons why Bush is supporting Mars exploration. You could call it the "red budget" instead of the "black budget".

Posted by: BruceMoomaw Apr 11 2005, 05:07 AM

Me: "...the problem is that [landed humans] WILL, at an absolute minimum, seriously contaminate every single local part of the planet that they actually try to examine scientifically."

Ciclops: "And what exactly is the basis for assuming this? That earth DNA will somehow jump into Martian DNA (if it exists) and modify it to such an extent that it can't be detected? Or that Earth organisms will suddenly thrive in the harsh Martian environment, far harsher than any on Earth, and destroy all Martian life? Or that Redpeace have just issued a press release?"

No; it's the fact that Earth DNA (and/or other terrestrial biochemicals) will get mixed in with Martian ones to the extent that we can't tell what chemicals we're detecting really evolved on Mars and which are misinterpreted terrestrial ones. In short, it's the danger that terrestrial germs and their biochemicals will so DILUTE any evidence of native Martian microbes (whether fossil evidence or still-living organisms) so much as to render that evidence seriously ambiguous in nature and so hopelessly confuse their study. And, to repeat, the environments that we most hope to find extant Martian organisms in are precisely those pockets of the Martian environments where Earth germs could live right now -- such as the subsurface liquid-water table, or near-surface polar ices that periodically thaw into pockets of liquid water. Even if we do find some Martian organisms so utterly alien in biochemistry that there is no danger of mistaking them for Earth microbes, we will have no way of knowing for sure whether Mars also evolved other organisms bearing a closer resemblance to Earth microbes.

This is hardly just my judgment -- as Donald Robertson pointed out a few years ago in "Space News", it's become the majority consensus among astrobiologists, and is a reason why they are coming to oppose the idea of any manned mars landings for a long time (as opposed to robotically returning samples of Martian surface material to Earth for study, perhaps selected efficiently by manned crews orbiting Mars). Certainly there is no remotely convincing scientific rationale for taking that last step and actually putting humans on the Martian surface for a long time -- as the Mars Strategic Roadmap group has noted, given both the danger of biocontamination and the difficulty of space-suited EVAs under the relatively high gravity of Mars, even a human crew on the surface would do a great deal of their exploration using robots controlled from either their home base or their pressurized rovers. In short, manned Mars exploration will, for a long time, be radically different in nature from what we became used to on Apollo -- so different that there will be little advantage in humans teleoperating those robots from the surface rather than from Mars orbit. Why spoil the possibility of so much invaluable scientific study just for the PR value of hastily putting one flag-waving clown on Mars (to paraphrase Tom Lehrer's deadly description of the Apollo Program)?

Posted by: Bill Harris Apr 11 2005, 09:25 AM

Good post(s), Bruce. The critical problem we face is ensuring that we do not contaminate Mars with our DNA or microbes. It would be terrible to not be able to determine if that bug or DNA fragment was ours or theirs.

Admittedly, Mars may be contaminated by earlier spacecraft or "earth meteors", but we can't risk more episodes.

Sending an orbiting laboratoryt Mars will be a tremendous undertaking, but the overhead of safely and sterile-ly landing a human on Mars is more tremendous. It's that last step down to qnd out of Mars' gravity well that is the dilly. For the cost (in terms of both $ and mass) of "one flag-waving clown on Mars" a dozen or more Rovers could land and work for many Sols.

--Bill

Posted by: Jeff7 Apr 11 2005, 02:54 PM

And even if Mars was already "contaminated" by meteors from Earth, that simply would show that life in some degree is capable of hopping from planet to planet without our intervention.

Posted by: dvandorn Apr 11 2005, 03:22 PM

Very good point, Bill. Especially about earlier spacecraft. NASA had all of the American craft designed to land on Mars sterilized, I know (the Vikings, Pathfinder and the MERs, as well as MPL), but what about MCO? And IIRC, the Russians did *not* go through a sterilization process on their Mars landers -- several of which sem to have reached the surface, if not in operational condition.

It's very true that a trace of biomatter on a crashed Mars probe is far less likely to contaminate the whole planet than a whole human outpost -- people exist in a veritable soup of microbes, parasites and symbionts. Our very breath contains organic material. Filters designed to keep such particles from moving one way or another are expensive and clog up easily -- they could be an answer for very short-term human stays on the surface, but would become a maintenance nightmare on a months-long stay.

By the same token, it's fair to say that human-delivered micro-organisms would get sterilized pretty quickly by the Martian surface conditions, as would any Martian microbes -- we're going to have to look beneath the surface to find any evidence of the latter, I'm sure.

It all comes down to intentions, I think. If we never intend to try and establish a human presence on Mars, then it makes sense to *never* even attempt to land there -- it would pose far too great a risk of contamination. However, if we *do* intend to put humans on Mars to stay, then by definition we will be *intending* to place a terrestrial environment on Mars (no matter what extent). In which case, the problem becomes maintaining "pockets" of uncontaminated Martian environments for study.

Since we're operating with a severe lack of information on the quantity, distribution and current status of Martian biotics, *any* discussion of cross-contamination -- either way -- is an exercise in energetic arm-waving. And since we're a long way from making firm plans about landing humans on Mars, we have many, many opportunities to expand our data on Martian biotics before we commit men and materiel to *any* such plan. Hopefully, by the time we *do* start serious work towards a manned Mars landing, we'll have more information and can make rational decisions about the contamination risks.

-the other Doug

Posted by: Bill Harris Apr 11 2005, 04:11 PM

No matter what our ultimate plans for Mars are, we need to be very, very careful about studying the baseline bio-conditions there. Mars in the most likely chance we'll have to study another (potential) biosphere in the next millenia and it would be nice to know whether or not life took root anywhere else besides Earth. The next candidates are Jovian and Saturnian satellites (Europa, Titan, etc) but it will be many yeasr before we get there.

--Bill

Posted by: dilo Apr 13 2005, 05:48 AM

Mode5. it seems they heared you!
http://img221.echo.cx/my.php?image=2p166143l2564jb.jpg

Posted by: Buck Galaxy Apr 13 2005, 06:07 AM

So how long do we wait? Say MSL or some other rover in the next 20 years finds Martian Microbes! Do we then NEVER land a human there? Supoose we don't find any? Do we keep looking for hundreds of years before landing humans?

Science is important and these questions must be answered, but at some point humans must walk on Mars. I think it is ridiculous to travel all the way to Mars and then never land. Surely the landing site will have a robot colony that will have completely investigated the nearby area and declared it microbe free.

Posted by: Bill Harris Apr 13 2005, 06:58 AM

I do not know. As a child of the space age growing up in the 1960's I have long dreamed of zipping up a spacesuit and clomping around on Mars. But now that we are wiping our feet on Mars' doormat I have reservations about leaving our molecular footprints until we find out what is there.

--Bill

Posted by: Mode5 Apr 13 2005, 07:36 AM

Too cool Dilo! Thanks for the followup. That piece hanging out looks out of place or had some heavy weathering. Are there any theories on it?

Posted by: paxdan Apr 13 2005, 07:46 AM

Earth and Mars have been swapping material since the formation of the solar system. We've found mars rocks here, even a bit of phobosite. And while earths gravity well is deeper than that of mars, I don't doubt that with the rich biosphere which has existed here and the near ubiquity of microorganisms in the first couple of Km's of the earths crust that at least a few bacteria have made the ride. I am certain also that we have sent life. I worked for a year as an undergrad in a Category 3 containment lab working with nasty pathogens, and while this doesn't make me an expert on biocontamination. If there's one thing I know it is that bacteria are tough little buggers and they get everywhere. I am confident that we have sent life (or its remnants) to mars on every craft dispatched so far.

In short I think the debate as to whether we should risk contaminating is moot. In fact I think the use of the word contaminate is wrong as it implies that some form of containment is being breached. Well those millions of kilometres of vacuum have been breached thousands (if not millions, or billions) of times during the last 4.5Gyr and we've done a good job in the last 45. It just isn't a pristine planet.

When we go to mars, of course we should do everything possible to minimise the exposure to our biota, but not at the expense of our next small step.

Posted by: cIclops Apr 13 2005, 08:30 AM

Yes, unsubstantiated speculation about contamination risks should not interfere with exploration, however the assumption that bacteria can survive ten of thousands of years exposure to solar radiation and hard vacuum in space, plus atmospheric reentry also lacks evidence.

Posted by: Bill Harris Apr 13 2005, 12:42 PM

Agreed. I _do_ think that we need to approach this cautiously in case irreparable harm is caused. Although Earth, Mars and neighbors have been exchanging material for eons, there is a difference between sending a rich source of biological material to Mars as opposed to a bug hitching a ride on a rock. Just as there is a fundamental difference between a natural process and a manmade action. There have been natural mass extinctions on Earth since time began, but if humans caused a "nuclear winter" or other catastrophe that would be looked at unfavorably.

I agree in principle, just be careful!

My own career has been devoted to minimizing the environmental impacts of mining on the surrounding countryside, and as such I look at myself as a _environmental_realist_, as opposed to an environmentalist.

--Bill

Posted by: Gray Apr 13 2005, 01:21 PM

Hmm, this topic seems to have split into two conversations; one about rocks the other about human exploration of Mars. I wonder if we should separate the two; or is everyone OK with the contrapuntal discussions.



Mode5,

The image you noted looks really neat. The rock in the bottom center of the picture looks as if it's crumbling from the bottom up. Perhaps the rocks are experiencing very slow mechanical weathering in a zone close to the soil. Could this be the effect of frost action over long periods of time?

Posted by: paxdan Apr 13 2005, 01:57 PM

What it lacks is direct evidence. All the components are there. If you were a bacteria http://www.nature.com/nature/fow/001019.html, makes sense seeing as the majority of big impacts are going to take place in the ocean. As for solar radiation i have no idea how big a rock you would need to preserve a sporulated bacteriaum inside a salt crystal, i'm not even going to guess. Reentry, in comparision, is the easy bit. It's ram pressure that causes the meteors to glow not friction, and the interior temps of meteorites above a certain size remain low. Below a certain size they slow to terminal velocity in the atmosphere and impact at a few hundred kph.

Really the hard part is the shock and heating casued by the impact that would be required to blast them of the earth in the first place.

<end panspermia related threadjack>

Posted by: David Apr 13 2005, 03:11 PM

If there were no intention of putting humans on the surface Mars, then I don't see any particular advantage to prioritizing a human mission to Mars. It seems to me that if we want to move in easy steps from moon landings to human exploration of other parts of the solar system, the natural sequence would be:
1) Near-earth asteroid rendezvous/landing (I don't think there are serious contamination issues here!); possibly a sequence of such trips, to work out problems in extended space missions
2) Manned Venus orbiter + unmanned probes (obviously this is a big leap from (1), but I can't think of anything in between)
3) Manned Mars orbiter (landing on Phobos?)

It's true that Venus is subject to more radiation; but that also means more power available for the orbiter . Exposure to solar radiation would be a problem for any extended manned space mission anywhere. Venus' advantage is that the travel times would be shorter. I'm not an engineer, though, so I have no idea what the technical problems would be in not only sending a crew out and bringing them back; I imagine they are different from, but not more complex than, returning a crew from Mars.