The recent impactor discussions brought up about the comet that may hit Mars brought to mind some vaguely remembered ideas about terraforming Mars. Volatile rich bodies are directed at Mars to give it an atmosphere of the resulting gasses. If my BOTE numbers are right, the estimated 30km diameter comet would roughly double the atmospheric pressure if it hit and converted all of its’ material to gas that didn’t escape. If that were the case, then 40-50 comets would give Mars an atmospheric pressure of roughly half Earth sea level. With the quantity of volatiles that either escaped Martian gravity, condensed to liquid, or just weren’t there in the first place, it would take 100-200 comets at least to get the job done.
That would give enough atmosphere for radiation protection, exploration with tanked air instead of spacesuits, and sealed but unpressurized living, working, and farming buildings. Compared to the advances of the last fifty years in space travel, this might seem a very long way off. Compared to the advances of the last century though, it might be much closer than any of us currently would think.
I know this concept has been kicked around for decades. My question is, “What is the recent credible work on it?”
johnhare
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I think it’s the wrong move to terraform the only planet other than earth that is already suitable for life. All they really need is abundant energy. Let the terraforming happen naturally as people move there and terraform their little piece at a time. I think it will take less effort and actually happen faster.
Venus is uninhabitable but much closer to earth in size. That’s the planet to practice terraforming on.
The big problem is that they have to be the right volatiles, H2O, which is probably going to be the bulk of what you get, won’t give you a high enough atmospheric pressure at a useful temperature, and if it did, there’s actually already enough water on Mars to cover the surface an average of 22 meters deep.
Maybe the target should be a blue Mars before a green Mars?
You only need ~1psi to go with just oxygen tanks. 2.5psi is significantly more comfortable, but 1psi can be adapted to. Both are significantly below your half of sea-level pressure.
Even the destruction from one or two comet impacts of that size could, combined with out-gassing from the enormous hot crater and feedback, be about enough to use just an oxygen tank in Hellas Basin.
My copy of Fogg’s Terraforming dpes not lie at hand. I remember much. higher numbers of impacts in the appropriate section.
Feels like a massive waste of perfectly good volatiles.
I just can’t see the point of terraforming Mars. We go to all this effort to get out of this life-giving gravity well because we think there are resource riches throughout the solar system, then we drop down into another gravity well and spend a few centuries trying to turn it into the equivalent of a high altitude desert on Earth, with the added bonus of no breathable air.
It’s like a kid wanting to leave their small, but pleasant, home town to make it big in the city… only to end up living on welfare in an even smaller, poorer, nastier town.
Even weirder, the very fact that you’re using resources from the rest of the solar system in order to make Mars even vaguely liveable (well, tankable), just shows that the resources are out there, not on Mars.
johnhare:the estimated 30km diameter comet would roughly double the atmospheric pressure if it hit and converted all of its’ material to gas that didn’t escape. If that were the case, then 40-50 comets would give Mars an atmospheric pressure of roughly half Earth sea level.
Jay Dugger: I remember much. higher numbers of impacts in the appropriate section.
A 30km diameter nucleus is unusually large.
I tend to agree with Ken here. Mars will be terriformed over time by settlers. Venus, OTOH, can be our terriforming guniea pig. Here’s a link to articles on the subject by Peter Kokh of the Moon Society. Note the article ‘Venus Geomorphed’ which discusses the idea of using comets to a) alter the atmosphere, and b) affect rotation… http://www.moonsociety.org/publications/mmm_papers/venus_rehabpaper.htm
Paraterraforming should not be overlooked. This is the step-wise creation of bubbles where terraforming to a high-level of living quality is done using limited resources. With time the entire planet is turned into a greenhouse. It is far less expensive and matches the needs of a the population as it grows.
Instead of having volatiles be free up to outer space, why not concentrate it to the pressure needed by humans?
Doug,
I tend to believe in exploring as many options as possible when it is cheap to brainstorm. Later on, when real operations are being set up, the most effective available methods for the intended use can be chosen. If settling the Moon or Mars is a tentative, individual, bit by bit operation, then obviously bubbles, domes, and caverns will be gradually built and expanded. If somehow before settlement starts, resources can be used early on to create some form of atmosphere, that might be preferable.
Much of it depends on time frame and available technology. If cheap inspace transportation becomes available, moving material to a planet might be preferable. If really cheap orbital atmosphere scooping becomes available, Venus may become the refueling point of the inner solar system. Von Neuman 3D printing machines could bubble the whole moon in this century.
Until it costs money or excessively intrudes on our time, I think playing these concept games is good. Of course, I’ve been wrong on many previous occasions.
If Ceres could somehow be maneuvered into Mars, there would be enough water to cover half the planet with oceans…
Warren,
While the very idea upsets most of the people here for quite good reason, it is a fascinating idea that could use some brainstorming.
Once we have the volatiles on Mars they will need a cover to prevent them from escaping.
Mars really is a frontier. Which means if we don’t automatically assume the colonists are slaves of either some government or corporation but are instead free people owning their own resources they will make their own improvements over time; especially if they own enough resources to start with (including nearly 500 plots) to finance whatever.
Abundant energy, not made expensive because their little community has no lawyers (or laws) to stop them, gives them enormous growth potential. The more we learn about mars the more we realize how habitable it is, as is. While not essential, the first reactors on mars should probably be integrated into landers we send there. Send two or more, owned by different companies, so they compete on price to the colonists. Even if only one, the colonists can choose to pay the price or just rely on their own methane from solar for industrial power.
Getting to mars is expensive (and will never happen without a plan that doesn’t make colonists foot the bill) but living on mars does not have to be. The key is individual ownership and a free market.
If you don’t see it, visit a rural ranch. Even if they have millions of dollars in assets (cattle and land) most actually live a very frugal life. That’s the model for mars.
Look at it another way. You live on mars in a spacious two story underground mansion with solar power and equipment to produce methane, water and oxygen from the martian air. More than you personally can use. Would you sell the excess power and gas to other colonists? How much would you charge? What if others also had excess and were selling it for less?
What if you saw a need for something the colony didn’t have? Would you pay incoming colonists for some of their mass allotment? They’re arriving with 1000 kg needing only half of that to survive. Might they sell you some of that? Instead of money, would they accept a starter home you’ve already built, ready on their arrival? Can people make deals if they are free?
It is many years before the colonists can make advanced electronic components. It is easier to make the big heavy stuff that is expensive to transport.
Carbon monoxide is a major competitor to methane as a fuel because it is easier to make and has a compatible temperature range to LOX.
Advanced yes, but most electronics can still be made from discrete components. Checkout the links on the last paragraph.
Winning end game of a colony has capacity to locally produce everything needed to survive and grow. Shorter term, local production of high mass/value items has priority. IC chips and semiconductors in general may be one of the last items produced locally. Once a local semiconductor fab facility is operating, the high end semiconductors may still be imported for awhile.
Peter,
“Winning end game of a colony has capacity to locally produce everything needed to survive and grow.”
I disagree. Look at nations on Earth, not one of them exists independently of the others. The “end game” is to be able to afford to purchase whatever you don’t produce by selling whatever you have in excess. To not have someone else supporting you at their expense.
Look at Australia, we are able to maintain a first world lifestyle, without being supported as a “colony”, primarily by exporting basic resources (iron, natural gas, and food.) We are capable of building an IC fab plant, but it’s still more efficient to import electronics.
This is why I consider Mars a lost cause. It can never contribute to broader solar-system-wide trade. Nothing launched off Mars will be cheaper than acquiring it from somewhere else in the solar system, nothing from Mars can never contribute to the broader economy. So Mars will never be financially independent (in spite of Ken’s proposed pyramid scheme.)
Historically, the difference between colonies that became nations, and colonies that failed, was their ability to be profitable, to produce something that the parent nations wanted. That pattern will continue into space. And it’s something that Mars fans always forget.