nuclear power for terraforming planets

Date: Dec 29, 2004

nuclear power for terraforming planets

Date: Dec 30, 2004

Well, that's an interesting, if rather dubious proposition.

The French have exploded several dozen nuclear devices deep in the volcanic rock of Mururoa, but as we saw, nothing of that magnitude will revive a dead volcano. (see http://www-dam.cea.fr/index.asp ).

Recent observations from ESA's Mars orbiter suggest that some of the volcanos may have been active relatively recently, on a geologic time scale, and that one or two might even still be feebly active today.

Maybe after several decades of research by a first permanent human outpost on Mars, something like that might be contemplated..... but other options may become more attractive by that time.

Date: Dec 30, 2004

I have to agree with Jaro. The size of thermonuclear explosives needed would be many many megatons (probably closer to gigaton yield) and would in all likelihood do not much more than contaminate a fair portion of Mars' surface with fallout.

If a big blast is what you want, a far better method would be to slam a series of asteroids into the summit of a volcano such as Olympus Mons.

Of course this will do nothing if the geologic potential for eruption is absent (read here as geothermal energy.)

A far easier, efficient, and benign way would be to construct large orbiting mirrors, kilometers across that could capture and reflect sunlight onto one or both poles. Concentrating enough heat into these regions will cause rapid sublimation of millions of tons of CO2 and water vapor. As CO2 builds up in the atmosphere, it will tend to trap heat (as would the water vapor.) Given time, additional mirrors, and introduction of Earth organisms (assuming there aren't any there yet!) I should think it should be readily possible to create a homey environment. Given centuries, and possibly thousands of years, our clever descendents should be able to walk on Mars' surface relatively unprotected. I think it could be done, but it would take us commiting to a project that we, and our immediate descendents will not see results from. Still, I think that it would be an excellent way for humanity to use its new found freedoms, knowledge, and resources. (And it sure beats the hell out of fighting over diminishing resources on Mother Earth!)

Date: Dec 30, 2004

these BTW are the observations I was refering to :

http://www.astronomy.com/asy/default.aspx?c=a&id=2692

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Mars geologists generally agree the planet saw volcanic activity within the last 100 million years. And such activity, if it still continues in the geological present, might account for some or all of the methane observed by Mars Express. Because methane doesn't linger in the martian environment, it needs replenishment. That could be the fingerprint of recent activity.

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.....another option for globally increasing Martian atmospheric pressure is large-scale manufacture of fluorocarbons with the highest possible GHG effect (i.e. preventing re-radiation of solar heat back out to space, thus increasing global temperature and polar CO2-ice cap sublimation....).

Of course methane itself if is some 20 x more GHG effective than CO2, while some fluorocarbons may be on the order of 100x more effective ( -- perhaps more - I need to find the reference reporting on that study....).

Perhaps a clever combination of several techniques, including the space mirrors and volcano triggering, may achieve the quickest results....

Date: Jan 4, 2005

Correct me if I am wrong, but I think that the main reason why the ORION project was cancelled was that it implied the manufacturing of nuclear bombs. Your idea could work politically if the bomb material were produced on Mars, it implies Uranium exploitation and nuclar power plants on Mars: it means that Mars would already be terraformed.

Like GoogleNaut said, terraforming Mars would take many generations. I can't help thinking of the building of cathedrals: the ones that started the work could not live old enough to see it completed. Humanity has done such things in the past, and it can be done again.

Date: Jan 5, 2005

Well, the creation of industrial infrastructure would signal the development of Mars--which is different from saying it is Terraformed. Terraforming implies changing Mars to become more Earthlike, whereas Industrialization does not.

I believe that Mars should in all likelihood have deposits of Uranium and Thorium which would be exploited by future colonists for energy and propulsion using more or less conventional mineral extraction, refining and processing techniques. There isn't really any reason why this woudn't work...so I would imagine that an extensive and sophisticated 'native' Mars industrial infrastructure should be well established within a century of the first manned landings. All it will take is a lot of intelligent people already living and working on Mars to decide that they want Mars to be independent of Earth for energy production isotopes. They will then find a way....

As for terraforming Mars--I would imagine that the future inhabitants of a mature human Mars population will decide that for themselves. They will already know much more about Mars than we do--so they will be in an ideal position to make this determination. Trying to rush it along might just screw it all up for us and 'them' (the future inhabitants of Mars.)

Date: Jan 5, 2005

Yes, I agree completely, this is good sense.

But industrialization is another thing than manufacturing bomb material: it requires a great effort to enrich uranium or to extract plutonium in large quantities.

Date: Jan 5, 2005

Its a "great effort" if you do it the old-fashioned way -- using gas diffusion or centrifuge techniques. A laser enrichment facility is very small by comparison.

Date: Jan 10, 2005

What is "laser enrichment" and how does it work?

Date: Jan 10, 2005

There are two types of laser enrichment techniques -- AVLIS, or Atomic Vapour Laser Isotope Separation, and MVLIS, which is Molecular Vapour Laser Isotope Separation. Both take advantage of the slight shift in photo-ionisation light frequency of atoms or molecules containing the lighter Uranium-235 isotope, versus the heavy U-238 isotope. Once the U-235 atoms are 'tagged' by ionisation, they are easy to separate from the remaining neutral atoms or molecules.

If you do a Google on AVLIS or MVLIS, you will find lots more information.

Date: Feb 4, 2005

I wrote earlier (Dec. 30 -- see above) that "some fluorocarbons may be on the order of 100x more effective ( -- perhaps more - I need to find the reference reporting on that study....)."

Well, it turns out I was waaaaaay off :

http://story.news.yahoo.com/news?tmpl=story&cid=96&ncid=753&e=10&u=/space/20050204/sc_space/bestwaytomakemarshabitableinjectgreenhousegas

Best Way to Make Mars Habitable: Inject Greenhouse Gas

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Gas of choice

The new research modeled how manmade greenhouse gases would affect Martian temperature and melt water ice and carbon dioxide ice at the poles.

Artificially created gases could be 10,000 times more effective than carbon dioxide in warming up the Red Planet, the study determined. The gases that would work the best are flourines and could be made from elements readily available on Mars, Marinova and her colleagues found.

<SNIP>

http://www.newscientist.com/article.ns?id=dn6973

Greenhouse gases could breathe life into Mars

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Runaway effects

Using computer models, researchers found that a gas called octafluoropropane (C3F8) produced the greatest warming in their study. The gas also worked well when mixed with other gases.

Adding this gas so that its concentration in the Martian air was 300 parts per million could spark a runaway greenhouse effect by evaporating the polar ice caps, which are composed of carbon dioxide. That extra CO2 - a greenhouse gas itself - would lead to even more melting and warming. This could help thicken the Martian atmosphere and increase atmospheric pressure.

But this amount represents 25,700 times Earth's annual production of fluorine- and carbon-based gases.

<SNIP>

Date: Feb 4, 2005

Greenhouse gasses could warm Mars--but I've got to wonder about the loss of atmosphere from Solar Ionization. If a planet's gravity well isn't deep enough, then it's possible for the upper atmosphere to become ionized and ablate away. Too a certain extent this happens to every world--even Earth possess a detectible ion 'tail' of hydrogen, oxygen and nitrogen--gassess readily available in the atmosphere. But since Earth has a relatively 'deep' gravity well, it holds on to much more of its atmosphere than say Mars. Mars possesses only about one-eighth of Earth's mass, it's gravity well is much 'shallower' giving gassess that much more potential to escape.

Adding gasses to the atmosphere of Mars is no simple feat--as you say Jaro, the necessary production of flourocarbons would have to be 'thousands of times' the production capacity of Earth--which is no small task. My best guess is that future inhabitants of Mars may want to augment global warming by increasing insolation.

By constructing large mirrors from materials extracted from Phobos and Deimos, the sunlight impinging on the surface of Mars could be substantially augmented. An array of mirrors in a sun-synchronous polar orbit could accomplish this task--but still engineering hundreds of thousands of square kilometers of mirror is no simple task. Not even doing the numbers yet, it would be my belief that the mirrors must subtend a substantial fraction of the total surface area of Mars to be effective. According to the CRC Handbook of Chem. and Phys., Mars possess a radius of an equatorial radius 3397 Km. Assuming a 10% augmentation of illuminated (dayside) surface, this is still about:

(1/2)*[4*pi*(3397*km)^2]=7.251*10^6*km^2. This is the equivalent of a single square mirror almost 2700 Km on a side! An orbital array of hundreds or thousands of mirrors will clearly be required. A single large mirror could be constructed as a single ring around the entire planet! Such a ring at a height of 1000km from the surface (radius=4397km,) and canted 45 degrees to the solar flux to direct the rays normally to the surface of Mars, would need to be about 233km wide across it's face.

Clearly such a scheme requires a vast engineering investment on a scale never seen before.

Date: Feb 5, 2005

In one of the articles, Robert Zubrin was quoted as saying that "These are 20th-century ideas on how to approach a late 21st-century, early 22nd-century problem" (refering to the GHG injection idea).

This could be interpreted any number of ways, but I take it to mean that a late 21st-century, early 22nd-century solution will involve large-scale application of nanotechnology.

Some ten years ago, there was an interesting article in the Journal of the Brit. Interplanetary Society (JBIS) about what you might call regional terraforming of Mars. As I recall, the concept involved "growing" a series of enormous, contiguous parasol-type structures that would be gas-tight, maintaining a life-supporting atmosphere under them, while allowing light in through their transparent domes. These cellular structures could extend for hundreds of kilometers and be capable of continued extension at the periphery, on an as-needed basis. Pretty nifty, I thought....