Should we terraform Mars?

[Dr Mordrid]

What with Elon Musk hell-bent on going to Mars with or without NASA, and the agency itself building the Space Launch System, the subject is being broached.

Astrobiologist Chris McKay's paper from NASA Ames....

Link....

Should We Terraform Mars?

As we continue to explore farther out into our solar system and beyond, the question of habitation or colonization inevitably comes up. Manned bases on the Moon or Mars for example, have long been a dream of many. There is a natural desire to explore as far as we can go, and also to extend humanity’s presence on a permanent or at least semi-permanent basis. In order to do this, however, it is necessary to adapt to different extreme environments. On the Moon for example, a colony must be self-sustaining and protect its inhabitants from the airless, harsh environment outside.

Mars, though, is different. While future bases could adapt to the Martian environment as well, there is also the possibility of modifying the surrounding environment instead of just co-existing with it. This is the process of terraforming – essentially trying to tinker with Mars’ atmosphere and environment to make it more Earth-like. Although still a long ways off technologically, terraforming the Red Planet is seen as a future possibility. Perhaps the bigger question is, should we?

One of the main issues is whether Mars has any indigenous life or not – how does this affect the question of colonization or terraforming?

If Mars does have any kind of biosphere, it should be preserved as much as possible. We still don’t know yet if any such biosphere exists, but the possibility, which has only increased based on recent discoveries, must be taken into account. Such a precious discovery, which could teach us immensely about how life arose on both worlds, should be completely off-limits. Small colonies might be fine, but living on Mars should not be at the expense of any native habitats, if they exist. The most likely place to find life on Mars is underground. If the surface is truly as sterile and barren as it seems to be, than colonies there shouldn’t be too much of a problem. It has also been suggested that Martian caves would make ideal human habitats, serving as natural protection from the harsh conditions on the surface. True, but if it turned out that something else was already taking up residence in them, then we should leave them alone. If Mars is home to any indigenous life, then terraforming should be a non-issue.

What if Mars is lifeless? Even if no life otherwise exists there, that pristine and unique alien environment, so far barely scratched by humans, needs to be preserved as is as much as possible. We’ve already done too much damage here on our own planet. By studying Mars and other planets and moons in their current natural state, we can learn so much about their history and also learn more about our own world in that context. We should appreciate the differences in and variety of worlds instead of just transforming them to suit our own ambitions.

There is also the more current but related problem of contamination. There has been a long-standing protocol, via the 1967 Outer Space Treaty, to have all spacecraft going to the Moon or Mars sterilized as much as possible. If bacteria from Earth made it to the Martian surface and survived, it would complicate the search for life there; if a lander or rover was to later identify living organisms in the soil, it might be difficult to determine whether they were just contamination or true native life forms. From both a scientific and ethical perspective, it would seem prudent to try to protect Mars as much as we can from earthly intruders. This applies equally to whether Mars is already inhabited or not. Fortunately, for almost any kind of bacteria or other microrganisms from Earth, it would be very difficult if not impossible to survive on the Martian surface, nevermind flourish. The risk of planet-wide contamination is very negligible, but it is still better to take strict preventive measures than to play with chance.

See also this excellent paper by astrobiologist Chris McKay. Some different views from this article on whether Mars should be protected and preserved at all costs or altered to help life to flourish there, but is a good presentation of the current ideas being put on the table. From the summary:

“Planetary ecosynthesis on Mars is being seriously discussed within the field of planetary science. It appears that restoring a thick atmosphere on Mars and the recreation of an environment habitable to many forms of life is possible. It is important now to consider if it “should” be done. To do this takes us into new and interesting territory in environmental ethics but both utilitarian and intrinsic worth arguments support the notion of planetary ecosynthesis. Strict preservationism arguments do not. It is important to have the long-term view of life on Mars and the possibilities of planetary ecosynthesis. This affects how we explore Mars now. Mars may well be our first step out into the biological universe, it is a step we should take carefully.”

[paulw]

If you ever want to live there without living in an airtight dome then lets terraform it..
It most likely will take years to do..

[Jammrock]

I always thought Mars lacked the mass to maintain a livable atmosphere.

[Dr Mordrid]

The mass wasn't the problem, the absense of a strong magnetosphere was. After its iron core solidified all Mars had left was a weak residual magnetic field inadequate to prevent the solar wind from blowing its atmosphere away - though it took billions of years to do it.

NASA Ames Chris McKay thinks it would take about 100 years to terraform Mars if supergreenhouse gases could trap solar energy with a 10% efficiency, less time if a higher efficiency is possible. Once established the new atmosphere wouldn't need all that much new gas to be maintained. Maybe just issue everyone an old Buick

[KRSESQ]

McKay seems to be making the argument that terraforming Mars should be verboten regardless of whether there's life or not. That's BS. A more relevent question might be, if there is life just hanging on in the martian environment, How might it adapt and flourish in a more Earthlike environment and would we want it to?

If Mars is indeed lifeless, then basically there's no environment to preserve. The whole planet might be treated as a blank canvas.

The backfires we've experienced as a result of our previous modest attempts at macro-engineering have made us timid. Instead of treating them as learning experiences toward a more perfect understanding of macro-engineering, we're letting those setbacks frighten us into believing the entire subject is somehow immoral or otherwise anathema to civilized society.

Ultimately the decision whether to terraform Mars will probably be made by the people who end up living there. They may choose to proceed whether us Earthlings like it or not.

[Brian Ellis]

Simple answer: NO WAY!

Apart from the scientific, technological and moral problems, the earth simply isn't rich enough to sustain a viable economy on both planets and it would be unlikely that Mars could ever be self-sustaining.

There should be an international treaty as per the Antarctic.

[TransformX]

Simple answer: NO WAY!
it would be unlikely that Mars could ever be self-sustaining.

I didn't bother reading, but if the soil is fertile enough to feed the population and there is enough solar energy or otherwise, they won't really need the earth to sustain them.

[Brian Ellis]

I didn't bother reading, but if the soil is fertile enough to feed the population and there is enough solar energy or otherwise, they won't really need the earth to sustain them.

If the conditions for life, as we need to know it for humans to live there sustainably, on Mars were acceptable, it would already be a green rather than a red planet. AFAIK, the soil is sterile, there are no water, carbon or oxygen cycles, it's cold and solar radiation would be insufficient to reach the threshold for photosynthesis to occur. As I said, the biggest obstacle would be economic and earth resources are barely sufficient for our own selfish and greedy needs; we could never afford to sustain life bubbles there as well.

[Umfriend]

Where should that gas come from though? Venus? Perhaps a very long hose being lifted over and above the sun? You'd need only about 600 gigameters of flexible pipes methinks.

[VJ]

I can see the moral problems behind it: it is not because nothing lives there, that we should start destroying the place. On the the other hand, if there is no life, it may be the logical next step of mankind.
If it has to be done, it should be done as a fresh start: carefully thinking what will go there, and not send anything there that can damage an environment (a bit contradictory, as terraforming is is essence changing the environment). We should not make the same mistakes again ("the solution to the pollution is the dilation" does not keep holding). Everything sent there should be used and recycled; everything made there should be recycled. And as Brian said: it should be self supporting, on everything (food, building materials, ...).

Umfriend: Wouldn't it be possible to extract/obtain gasses from rocks (e.g. through some engineered bacteria or so)?

[Dr Mordrid]

Water: subsurface ice all over the planet. Just the south pole has >1.6 million cubic kilometers.

Carbon: at the poles or in winter frozed CO2 at or nead the surcace, and the atmosphere is 95% CO2 - a basic requirement for plant photosynthesis..

Minerals: most everything, especially water generated oxides and lots of iron, magnesium and other metals.

Gardening: you don't need soil if you use hydroponics, a proven tech already used for industrial scale farming on Earth. If you've eaten lettuce, cabbage, 'greenhouse' tomatoes etc. in the US a large percentage were hydroponically grown. Simple self-sealing plastic inflatable domes (greenhouses) trap heat and with basic machinery stabilize the gases.

ISRU (in-situ resource utilization) can generate liquid water (and therefore oxygen and hydrogen), methane (H2 + the CO2 atmosphere) and there is also trace methane in the atmosphere, and many other chemicals using known basic processes.

One of the very basic Mars scenarios involves sending a large lander with ISRU hardware and tankage to generate methane, water and O2 before humans arrive using the Sabatier reaction;

4H2 + CO2 --> CH4 + 2H2O

With H2 being on the lander and CO2 from the atmosphere. The methane is stored, and most of the water is initially electrolyzed to produce O2 and more H2 for producing more methane (solar and/or RTG power.) CO can be generated, along with more O2, using zirconia electrolysis cells.

Methane, CO2 and CO are rocket fuels usable for the return ride, going to phobos or deimos or transporting cargo around Mars. CO or methane burn with O2, and CO2 can be used with magnesium from the Martian soil in a hybrid rocket. Methane is also an excellent supergreenhouse gas for kickstarting the warming of the planet.

[Brian Ellis]

Water: subsurface ice all over the planet. Just the south pole has >1.6 million cubic kilometers.

Carbon: at the poles or in winter frozed CO2 at or nead the surcace, and the atmosphere is 95% CO2 - a basic requirement for plant photosynthesis..

Minerals: most everything, especially water generated oxides and lots of iron, magnesium and other metals.

Gardening: you don't need soil if you use hydroponics, a proven tech already used for industrial scale farming on Earth.

ISRU (in-situ resource utilization) can generate liquid water (and therefore oxygen and hydrogen), methane (H2 + the CO2 atmosphere) and there is also trace methane in the atmosphere, and many other chemicals using known basic processes.

One of the very basic Mars scenarios involves sending a large lander with ISRU hardware and tankage to generate methane and O2 before humans arrive using the Sabatier reaction;

4H2 + CO2 --> CH4 + 2H2O

With H2 being on the lander and CO2 from the atmosphere. The methane and O2 are stored, and most of the water is initially electrolyzed to produce O2 and more H2 for producing more methane (solar and/or RTG power.) CO can be generated, along with more O2, using zirconia electrolysis cells.

Methane, CO2 and CO are rocket fuels usable for the return ride, going to phobos or deimos or transporting cargo around Mars. CO or methane burn with O2, and CO2 can be used with magnesium from the Martian soil in a hybrid rocket. Methane is also an excellent supergreenhouse gas for kickstarting the warming of the planet.

Sorry, you have not thought this through.

To generate methane from CO2 and hydrogen is a highly endothermic reaction (even the phase change from ice to water is endothermic!). Where is your energy coming from to provide the necessary heat? Also you will need vast quantities of energy to generate the hydrogen? Dammit, if it were as easy as that to convert CO2 to CH4, why do you think it is not done on earth to reduce the CO2 levels?

Your last sentence is even more far-fetched. CH4 has a low global warming potential (~25 on a 100 y scale). You would need a much more stable substance such as perfluoroethane with a GWP of ~10,000 by the teratonne to start warming a whole planet significantly, with a suffocating atmosphere. Furthermore, a methane atmosphere with sufficient oxygen to support life would be highly explosive (change the orbit nearer here???? )

Sorry, Doc, bring your head out of the ozone layer and plant your feet firmly on terra firma; I'm not a science fiction fan.

[KRSESQ]

You guys are overlooking the importance of robust volcanism in the formation of a viable biosphere. The first life on Earth probably formed around hydrothermal vents at the bottom of some primordial sea.

My guess is that there is probably not enough volatiles trapped in Mars' ice to significantly increase the atmospheric pressure even if we could get the planet warm enough. It would take a LOT of volcanic outgassing to reach a threshhold at which true terraforming can be said to have occurred.

Unless Mars can be made geologically active enough, chances are any imported Earth-life would have to stay under pressurized domes forever.

As for a Mars colony being self-supporting, that depends on the availability of raw materials. No wood, obviously, so all construction would be stone and concrete (marscrete?). Other mineral resources are obviously unexplored. Some machinery would have to be transported from Earth, at least until local industry could be established. Power would be solar, at least initially, and nuclear. Otherwise it wouldn't be a whole lot different from establishing a colony on some inhospitable corner of the Earth, except perhaps in scale.

[Dr Mordrid]

Brian: It is you who didn't read the whole post.

Those ISRU techniques, and the power sources for doing them, have already been worked throgh. And they aren't mine - they're NASA's, Russia's and the various companies who work with them.

For example; RTG's produce both electricity and huge amounts of heat; 500 - 100,000 watts of it with a half-life of 87 years if Pu-239 is used - but it's not the only option. Normally this heat is dumped by large radiators, as in space probes, but in ISRU it can serve other purposes. It can be channeled off using numerous methods, a little or a lot at a time.

For initial fuel needs you send a low boiloff fuel tug/lander of H2 to Mars from L2, whch is a low energy fast transit. SpaceX calls this the Dragon's Nest.

Space energy needs differ from "normal" earth needs. The use of methane, CO2 and CO are nothing new for rockets & ISRU and for Mars they are ideal, and space agencies have done a ton of work on them. This is especially so for methane which SpaceX may well use in its next engine.

As for methane as a greenhouse gas, it has one big advantage: it can be made in place using simpler ISRU methods than hauling halides and other precursors and gear to Mars - at least initially. For one thing, early use equipment will already be there for fuel production. Once the chemical production infrastructure is built up a bit more a changeover can be made.