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China is planning to put a Rover on to Luna.  It will have nuclear power so it will be able to run for weeks and have the power to send high bandwidth data back to Earth.

Interesting to see if they can pull it off.

More information is here...

http://www.theregister.co.uk/2007/04/03 … oon_rover/

Warm regards, Rick.

Edit: This post was supposed to be placed in unmanned missions.  Clumsy of me.  Moderator, if you have the time could you move it so it will be easier for people to find.

Warm Regards, Rick.

Hi Everyone,
When reading this forum every now and then someone says, "and nanotechnology robots will solve THAT!"

I just want to say that independent nano-technology robots are a long, long way off.

--- Rant mode on. ---

I read "Engines of Creation" by Eric Drexler, and it felt more like a religious tract than something with real science.

There are severe problems with the independent robots view of nano-tech that most people ignore.

- POWER: I've hand people tell me about nano-bots that swim thru my blood stream zapping viruses.  Or little machines that burrow thru the rock finding useful metals, etc. "Where do they get their power?" I ask. "From your bodies heat!" they tell me. For a heat engine to work you need a heat differential. And one side of this microscopic bot is the same temperature as the other.  Don't people know about the laws of Thermodynamics?

Others talk about putting an antenna on them and receiving power from radio waves.  I ask them how an antenna a few atoms long are going to absorb a wavelength measured in meters.  A shrug; they don't know what I'm talking about.

Other people talk about using a system to convert light into mechanical motion and using a rack and pinion system and clockwork springs to store energy. When I ask them to sketch out how this system would work I get shrugs. Light (at least that found underground or in the body) is not powerful enough to knock atoms about.  It gets absorbed into the electron shell.  So a system to mechanically covert this to motion in a rack and pinion is not trivial.  Ah, well, at least the second system is not physically impossible in theory.

A person said that the nano-bots could take in sugars (from our bloodstream) and burn them producing wastes which are dumped back into the bloodstream.  Ok, this could actually work.  You will need enzymes to act as catalysts, ways of storing this power and systems to clean out the gunk produced by burning these substances.  All of these systems push up the size of the nanomachines (which limits their mobility and  usefulness) but again this system is possible.

-  SMALL IS STICKY:  People talk about the nanobots grabbing this atom here, that one there and assembling useful stuff. The problem is that those atoms are stuck together. Really tightly in some places and it takes a lot of power to wrench them apart when you are few hundred atoms in size. And when you grab one atom from a molecule both halves now want to stick to things. The piece you broke it away from, other stuff drifting around, your machine. When you put it on a half finished robot that robot has 'sticky' surfaces all over. What will stop some thing else coming along and attaching itself on your half done machine? Now you are not just building a machine you are cleaning random, chaotic debris off of it as you try to build it.

- SMALL IS DIRTY: On the atomic scale you have all sorts of elements and molecules everywhere and many of these have sticky surfaces. Glom some of them on your machine in inconvinient places and it stops working. When I ask enthusiasts for nano-technology about this problem I get suggestions like windshield wipers to brush off this stuff, or suggestions that free radicals and 'sticky' atoms don't exist in large enough numbers to be a problem. (Even tho your machine is creating such things locally.) Others talk about smaller nano-bots crawling over the bigger ones removing bad atoms.

To clean off this sticky crap is NOT an easy process. It will take a fair bit of brain power to know how to approach this particular jam, or that molecule's edge, wedged in there.

- PROCESSING POWER: Where do the brains for these robots go? People talk about using rods in carbon nano-tubes to store information. (If the rod is up 3 atoms it means something different than if it is up 4 atoms.) No reason rod logic can't work, but tho very small to us, it must be gigantic on the atomic scale. Nano-bots will have to deal with a very, very complex dirty world. Much of it will be dark and if you say, well put lights on it, the whole question of power comes up again.  (And then you need the processing power to figure out that visual information in a world of difraction and interference rings.)

These machines will need a TONNE of processing power, to figure out what is in their environment (sensors, pattern recognition), will have to make plans in a chaotic environment, will have to move over potentially sticky, magnetic or electrostatic terrain. They will have to coordinate with other nano-bots for big projects, etc. And as the processing power goes up the nano-bots get larger and larger. Their power requirements go up. There are ever more surfaces that random stuff can stick to.
I've had people say that each nano-bot will have low processing power, but they all will find each other, link up into a super network, figure everything out, program each tiny bit of themselves with detailed instructions and then each bit will diassemble and go out do its thing.

Ignoring how difficult all this is I ask a very simple question. I ask how they will link together and exchange info? "There will be holes so that the rod logic can push rods into each other." Well, what if there is dirt or stuff stuck to the side of one so there is not a tight fit? "No problem, we will just put windshield wipers on them!" What will keep stray atoms from getting into the holes? "No problem, we will just put little powered hatches on them!" etc.

Let's just say I'm more frightened by the iron death of the universe than I am by "grey goo".

I ask that anytime someone wants to fix a tough terrafoming problem with self replicating nano-robots, they either:

A) Discuss how the above problems would be solved.

B) Admit that this is for the FAR future.

or

C) At least wait until we have experience with swarms of insect sized robots doing some useful, productive work before you magically solve problem with robots that have an enviroment that is orders of magnitude more complex.

---- Rant mode off. ----

For an interesting story about insect sized robots you might want to check our James P. Hogan's "Bug Park". It is a lot of fun & has some good lessons for what happens when you shrink scales.

Regards, Rick.

In "Terraforming: Engineering Planetary Environments" by Martyn J. Fogg he has a chapter that talks about this.  One suggestion was to take two high peaks and put a series of mirrors on them that would reflect a powerful laser beam back and forth between the mountains.  (See page 166.)

This laser would be tuned to break up chlorofluorocarbons.  As months go by, these trace substances are eliminated from our air.  (This reduces greenhouse gasses and substances that destroy the ozone layer.)

We have to make sure aircraft, people and birds and animals don't go into the beams or they will be fried.

Anyway it was an interesting idea and the only way I've seen suggested on how to speed the break up of these substances.  If you don't have fission or fusion, you have to watch the atmospheric pollutants that you create to power these megalasers.

Warm regards, Rick.

This is the time line as I see it for Terraforming Mars.  I won't bother listing my references (most of them on in the Terraforming books reviews that I have been posting anyway).  I have been studying this topic with some determination for half a decade, and I think these estimates are likely more accurate than most.

If anyone has questions about a particular point I make below feel free to ask about it.

YEAR 0:
Move in Solletta's over (behind) the poles to warm the high latitudes.  Humans start releasing green house gasses but it will take 100 years to build up the industrial facilities to really significantly start affecting the atmosphere.  Dropping some small comets on nitrate beds will speed things up but I will ignore this idea for the first 100 years or so.

YEAR 4:
All CO2 on the surface of both poles have evaporated.  Mars' atm pressure is at 20 mbar and rising as the soil warms and out gasses CO2 absorbed by it.  (I am being more conservative in this estimate than Zubrin here as I think that the soil will be buffered by a fair bit of ice which takes more energy to warm.)

YEAR 20:
With the pressure of CO2 rising, the air can absorb more heat and move it better.  This is a positive feedback cycle.  Mars is about 10 to 15 C warmer which is enough to put significant parts of the planet above the triple point of water brines.  More water frosts out each year but much of it melts under the year long sunlight from the mirrors.  This melting water carries heat deeper into the soil.

Note that the ice being made now is pure water and not the CO2 cathrates I believe to be common on Mars.  As ice replaces cathrates, more CO2 is released into the atmosphere.  The atmosphere is likely around 50 mBars.

YEAR 100:
Frosts are turning Mars white which lowers the albedo.  This is balanced by the atmosphere pushing 75 to 100 mBars and a significant increase in super greenhouse gases.  (Nitrous Oxide, Sulfur hexafluoride and various perfluorocarbons.)  This is where the sollettas are key.  Without them (say just greenhouse gasses) any water vapor just freezes out on the poles.  However significant melting happens each summer at the poles as they get all day sunlight and the air is warmed at the medium and high latitudes by the solletta.  The goal is that most frost melts pretty much planet wide by evening each day.  If not, we must wait longer for more greenhouse gasses.

People can now walk around in winter clothing and oxygen masks.  Tho cyanobacteria were likely introduced earlier they hopefully should be taking off now and spreading.  They are releasing O2 to the air.  Tho millennia away from a breathable atmosphere the O2 will start thickening the ozone layer and stopping more ultra violet light.  (The thicker atmosphere will also be stopping 10 times more cosmic rays making moving & working on the surface safer.)

I will assume that larger mirrors are placed over the poles around this time.  This will greatly speed the warming of the planet.

YEAR 100 TO 200:
A wide variety of simple plants are added to the warming Mars.  They struggle for a long time.  (No soil, there might be toxic dust left, high UV levels, low pressure, missing bacteria symbionts, lack of biologically fixed nitrogen and other minerals in forms that life can use, etc.)  I think that it is likely in 200 years a few simple ecologies have started.  These ecologies are anaerobic so much of Mars life is brown and smelly.  O2 levels are rising but very, very slowly.  This helps with the ozone layer.

Liquid water is common and the H20 in the air is a powerful greenhouse gas helping to keep the planet warm.

YEAR 200 TO 500:
Warming the first few meters of the soil is fairly easy but it is much slower the deeper you go.  I think it likely that Mars has huge reserves of CO2 in deep brine aquifers and vast amounts of CO2 cathrates.  In 500 years much of the CO2 reserve will have been released.  Atmospheric pressure is likely 1/3 to 1/2 Earth's pressure and ice is melting everywhere.  Permafrost, floods and snow is common.  Arctic ecologies are possible in some areas.

Tho much of low laying Mars is now hospitable to life it will take centuries for life to spread to it.  Humans can shorten this by doing a lot of work to try to develop widely spaced ecologies.

(Note that increasing the free O2 to 1% of Earth's level is still a big improvement.  A life support system can use a compressor and some simple chemical reactions to get O2 out of the air rather than having to lug bottled air along or needing huge greenhouses for a base.)

YEAR 500 TO 2000:
Some time between 500 and 2000 years after we have started terraforming Mars a healthy ecosystem is widespread in low laying areas.  O2 levels rise rapidly at first since the rocks are already oxidized.  However, the problem is that some plant sucks CO2 out of the air, holds that carbon for a few years.  When it dies it rots and releases the carbon back into the air as CO2.  So the O2 level will rise steadily as more and larger plants grow but will stabilize at a (low) level until the biosphere can make large gains in mass.  Even tho the air is not breathable, the O2 makes a significant ozone layer which protects water from dissociation and makes the surface much more pleasant.

Now arctic swamps will slowly bury unrotted peat moss like stuff which will very slowly suck CO2 out of the air.  This will take the 100,000 years that McKay & others estimated for how long it would take to give Mars a human breathable atmosphere.  However if humans take big trees filled with carbon, cut them down and bury them (or take them to the top of high mountains which are sterile and out of the biosphere) we can lock up the carbon.  Life will have to suck new carbon dioxide out of the air.

Note that Mars cools as CO2 is absorbed, but the air pressure stays the same since O2 is replacing it.  Something will have to be done to keep it warm.  (More comets? More greenhouse gasses?) 

I vote for comets because at this point, we will want to have a fair bit of nitrogen to buffer the air and help nitrogen fixing plants.

If we artificially bury vast amount of carbon the time to get a human breathable atmosphere can be greatly reduced.  (2000 years?  5000 years?)  However it has taken us hundreds of years to dig up the coal that is currently filling our air with CO2.  We have to bury vastly more carbon than those coal beds and instead of giving us energy it costs energy.  I suspect that this will happen in spurts with long periods where people don't bother.  However a several thousand year push will give the colonists a high enough O2 content for flying insects.  Once we have bees we can add millions of species of plants that need insect pollination to reproduce.

We likely will have breathable levels of O2 in the air long before the air is breathable.  CO2 is toxic if the partial pressure is too high.  Virtually ALL of the CO2 has to be drawn down first before people can take their first breath of unprocessed air.

10,000 to 100,000 years (depending on the the colonists):
A 'world wide' breathable atmosphere (at lower elevations).  Note that in the lowest areas people might be able to breath long before someone a couple km higher.  So people might push to get a breathable atm at the -4 datum, and several centuries later start pushing to allow people to breath at the -3 datum etc.

So when people ask me how long does it take to terraform Mars, the answer is complex.  50 to 100 years can make the planet a lot easier to live on, 500 years will give you ecologies, a nice thick atmosphere and a significantly improved ozone layer.  5,000 years will allow insects and I think that even optimistically it will take 20,000 years before anyone walks around on Mars with out a breather mask.

If we get fusion (especially He3 fusion) then these numbers can be sped up.  Hot water could be pumped deep into frozen aquifers to release water and CO2.  High powered spaceships can move a lot of mass to Mars and perhaps start giving it a nice big moon.  With vast amounts of energy it is a lot easier to find fluorine, dig it up, and pump it into the air as greenhouse gasses.  It is a lot easier to bury the carbon.  It is easier to collect a lot of radioactives from all over the solar system and send them on a one way trip to the Martian core (to start some volcanoes).  If we have generous power we might be able to shave off 10 or 20% from the times I give.  If we are power starved then triple the times or just say it is impossible.

Those who talk about nano-technology saving the day or gene engineering plants to be vastly more efficient have no idea of how hard these ideas are to implement.  Yes they might happen, but I have some severe doubts.  A discussion on them would likely be a good post for another day.

Warm regards, Rick.

Rather than using 3 legs I would use 6.

Radar on board finds a generally flat area and it goes into vertical landing mode (like a jump jet).  As it decends the legs start to touch down on rocks and the like.  Give each leg a 50 to 70 cm of 'give'.  If at least 2 legs have not touched down on the other side of the plane by the time it has used most of this give, then rise up a bit, move forward a bit and try landing again.

Extra legs make it a lot easier to find a stable landing zone.  (The cost of this is the mass of the extra landing gear, but since this is mission critical I feel it is worth while.)

Warm regards, Rick.

In the Case for Mars a system is described where methane is created from hydrogen imported from Earth. The URL below describes a system where the methane is turned into aromatic hydrocarbons. This reduces the amount of hydrogen which needs to be imported to Mars by a factor of 4 over the methane fuel created by the Sabatier reaction.

(Note: aromatic hydrocarbons are ones that contain benzene rings. They have a distinctive smell which results in their class name.)

// Go to the link below and then look for the article called "
Mars Aromatic Hydrocarbon and Olefin Synthesis System"
http://www.pioneerastro.com/projects.html

Benzene (C6H6) is created with the reactor described in the article. Note that the chemical has 1 hydrogen for every carbon atom. Thus the fuel needs less hydrogen per carbon to be burnt by the oxidizer.

There has been significant advances in the field of using catalysts to turn methane into aromatic fuels as this would allow methane (natural gas) to be economically moved from natural gas fields which are too remote for a gas pipeline. One problem is coking (carbon build up) on the catalysts. This article describes techniques which lower the speed of the reaction but greatly extends the life of the catalysts making it suitable for working on Mars.

The group also created better catalyst for this reaction (Mo-Zr/HZSM-5 zeolite catalyst).

the key formula is:

6 CH4 --> C6H6 + 9 H2 + heat

Benzene and liquid oxygen have a Isp close to LOX/Kerosene. Small amounts of toluene (C7H8) and naphthalene (C10H8) impurities does not affect performance. (In fact if burnt in a slightly oxygen rich environment the naphthalene actually gives a slight boost in Isp.)

This great boost in efficiency means that the hydrogen can now be shipped to Mars as either water or methane which are much more reliably stored in vacuum environments. This is important as it allows this process to be used by small probes where hydrogen boil off would be a real problem.

Another advantage of this system is it takes less power than the Sabatier system. Additionally it requires less O2 oxident and this further reduces power requirements.

SUMMARY:
This system makes sample return missions and human missions to Mars cheaper and more reliable.

The above is a neat propaganda trick to make it seem that we are on the same side and to further your agenda that there is a lot of junk science on climate change.  Actually there is very little junk science on the subject apart from what Exxon and its siblings are funding.  See below.

In a propaganda war one side says "True, true, true"  the other side says "False, False, False" with neither side expecting to convert the other.  The purpose is to sway people who are not converted to one side of the other.

I have better things to do with my time. 

A rational or scientific debate works on a different principle.  People explicitly create a thesis, and show the evidence and logical interference that supports their case.  They do calculations showing where all data has been gotten and showing each step of the process.  And when something that their argument depends on is attacked they either defend it or admit they are wrong and change their mind or modify their thesis to take into account the better data.

Let me give an example.  I did a calculation in another post and I showed,
a) where I got my data...
b) the assumptions that this calculation is based on...
c) each step of the calculation was done in the open.

Doing it this way puts myself at risk.  If I multiply instead of divide then I look stupid, publicly.  However the advantage of this method is that peer review has the highest chance to find mistakes.

You championed this bogus documentary.  I spent some of my all too rare free time and found very strong evidence that this show is BS.  If we are really in a rational debate and not just trying out yell each other, then you have to either say, "so sorry, it was full of BS.  I'll edit or delete my post so as not to deceive others" or DEFEND the sorry thing. 

So are you willing to either delete the link to that vile propaganda or are you willing to defend it?  If you are not willing to do either than in my own mind you are not worth wasting time on; you are some one undeserving of my respect.  I give people in this forum the benefit of a doubt and ASSUME that we are actually are in a rational debate.  So far I've singled you out because you have chosen to support a spectacularly shoddy bit of propaganda.  (It makes shooting fish in the barrel easy.)

Another principle that is used in rational debates is Ockham's razor.  This says that if you have two hypothesis that explain a phenomenon, the simpler one is likely to be true.

Rick's theory: "The consensus of thousands of scientists is that we have, human caused, climate change.  This is very dangerous in the long term.  A few scientists who are largely funded by Exxon and other fossil fuel corporations dispute this."

Martian Republic's theory: "Prince Phillip has created this environmental movement to scare people.  And he controls Gore.  And scientists, hundreds maybe thousands of them, are all lying because they know that they get more funding that way.  Sure, Exxon is funding the good scientists but hey, good for them, they are supporting the truth!"

If you honestly want me to revise what I understand about meteorology, physics, chemistry, history, what is happening in my own province and country, what I see with my own senses and what I believe about the effectiveness of the scientific method and rational thought, then I suggest you do not champion such nonsense.  Going to some effort to gain back my respect would help.

See above.  Are we in a rational debate?

Humans construct stories to explain the world in their own minds.  This is how I see the climate change story:

Tthe USA body politic has been polarized into two camps.  Bush & the Republicans say that global climate change is not happening / might be happening but scientists can't agree / is happening but is not caused by humans and in any case is nothing to worry about.  (Pick a month in the last year to get their spin at that time.)

The Republicans have a very easy to understand reason to do this.  They have major ties to big oil.  Bush has personal ties with the House of Saud.

Human beings have evolved to collect into tribes.  We see it in gangs in the inner city, clans in virtual worlds and political parties and nationalism.  (I find it interesting how quickly and easily clans form with strangers in a virtual world.)

I have people in my extended family.  Some voted Socred.  Everything that they read was run thru the Socred filter.  Socreds basically told the truth.  When the media reported something good about the Socreds it was true.  When the media reported something bad about the Socreds it was an exception / exaggerated / a media lie.  They were part of the Socred tribe and viewed the world that way.

Other members of my family belong to the NPD tribe and likewise filter their data to conform to their world view.

Now we are seeing the Liberal world view springing up. 

These people can't talk to each other because they can't agree on the data, social values or the processes of political thought.  Anytime they talk about politics there is a fight.

(As for myself I dislike ALL of the political parties.  None of them represent my views so I usually vote for the underdog to keep the politico's on top nervous.)

This is what I see happening in the USA.  I think that the progressively nastier and dirtier political tactics that are being employed will result in a fight, especially if people feel that they are being prevented from getting a voice in their government.

Back to my main thesis.  There are lots of people who are in the Bush tribe and if some Exxon funded 'scientists' say we don't have anything to worry about then by damn they are ready to believe it.

Others are in the Democrat tribe.  If Al Gore says that Global Warming is a problem then, no shit, they are ready to believe that!

I am in the Rationalist / Scientist tribe.  When someone says that thousands of scientists all over the world for the past 6 decades have been falsifying data and lying, well it pisses me off.

If the stakes were not so high I could easily ignore it.  But I think that the world that my grand kids will be living in will be significantly worse than if we tackled this problem now. 

There are other worries.  Humans are causing the 6th great extinction event in the Earth's history.  That is very troubling.  I think that climate change will make this worse as we are already seeing species undergoing environment stress because spring is coming earlier and the like. 

(e.g. Caterpillar eggs hatch when it gets warm.  A species of bird migrates and eats these caterpillars.  However the bugs are hatching 3 to 4 weeks early and the birds are not finding the food source for their young when they arrive and lay eggs.  Significant drop in the population of birds.)

There is a very good book called "Collapse" by Jerad Diamond.  He documents several civilizations that have collapsed because they over exploited their environment.  Interestingly, all of these civilizations collapsed just after they were at their richest, most populous and most 'efficiently' exploiting their environments.

I think that people don't realize how good we have got it now.  If our civilization collapses the few survivors will have a very miserable existence.  Furthermore, we have burnt the easy to access petroleum deposits that have such concentrated energy that they can raise civilizations.

I think it is a distinct possibility that Humans may face extinction in the next 500, 2000 or 5000 years or so.  If we can keep a high technology (avoid collapse of our global high tech civilization) then this is a non-issue.

If humans can get off Earth and colonize Mars the chance of our species surviving the next 50,000 years more than triples in my estimate.  The USA over the last 40 years has totally dropped the ball on space development.  However, Europe, India, China and Japan all have aggressively growing space programs and all (except perhaps Europe) have stated that a long term goal is colonizing Mars.  (China has damn near said when they land on Mars they own it.) 

Good for them!  The most important, absolutely vital thing, is that humans get off this planet.

Anyway, this is the story in my head that drives me to waste my time in a Mars Forum.

Sincerely Rick.

Hi everyone,
  In this forum:

http://newmars.com/forums/viewtopic.php?t=5295

  I wrote a review of the book "Mars: A Warmer Wetter Planet" by Dr Kargel.  I think that this book would be of great interest to the Water on Mars forum and invite discussion here on the book and the exciting (or perhaps outragous) claims he makes.

  If you discover references that support or undermine his main points, this would also be the place to put them.

  Warm regards, Rick.

"Terraforming: Engineering Planetary Environments" by Martyn J. Fogg, published by the Society of Automotive Engineers, (c) 1995, 544 pages, hardcover.

This book is long out of print. I found used copies at the big online book sellers (Amazon wanted ~$1,000, what a rip off). However, B&N, & other book sellers were asking about $300.00 US. I picked up my copy at Alibris & it was shipped to my place within the week.

This is a seriously fun book (if you are into science geek type fun).

This is written like a science text book and seems to intend to place itself as the definitive book on terraforming. I feel that it succeeds in this goal. It starts with a review of terraforming from its first discussion in the pages of science fiction to its current state of semi-respectability in scientific publication (such as the journals "Science", the "Journal for the British Interplanetary Society", "Nature", "The Environmentalist", "Advances in Space Research" & "Speculations in Science & Technology").

The book is written for the interested layman. It does include a variety of formulas but these can be ignored with out losing the main thrust of the argument. The book is literate and easy to read.

The most useful part of the book is it is a reference with truly hard to find data of interest to terraforming neatly organized in one place. e.g. I had been looking for what would be the best mix of perfluorocarbons mostly likely to be first used as the first artificial greenhouse gasses on Mars. I could not find the IR wavelengths absorbed by these compounds anywhere, but the information I wanted was right there on page 238. (Such as exists in 1996, many of the values needed have not been studied by scientists at that time.)

(See this:

http://www.newmars.com/forums/viewtopic … 9&start=55

for new information posted by Rxke.)

After a discussion on guidelines on how to best intellectually approach terraforming, Chapter 4 talks about planetary engineering of Earth. The major thing that I took from this is that it is a hell of a lot easier to prevent our planet from becoming overheated, polluted, and fighting the spread of vast deserts than it will be to reverse these after they have happened.

Mr. Fogg makes a distinction between "ecopoiesis" (low effort, largely biological terraforming intended to make a bacteria biosphere on a planet) and "terraforming" (higher effort means to make a world suitable for human life).

The book is not highly theoretical. In addition to the chapter on saving Earth there are two chapters on terraforming Mars, one for Venus and a further chapter discussing the possibility of ecopoiesis and or terraforming on other bodies in the solar system (not real likely with out magical nano-technology & the like).

This is the first book that gives me numbers for atmospheric erosion by asteroid and comet impacts. (On Mars, asteroids of 5 km radius or less and comets of 1 km radius or less should not cause any significant atmosphere erosion.) He also discusses using impacts to release volatiles such as CO2 and N2 from carbonate and nitrate beds. (Big impacts are wasteful of energy; splitting the incoming bodies into 200 to 500 meter chunks and directing them to exact targets are better. However, he prefers exploding exactly sized thermonuclear bombs (H-bombs) to more efficiently release these substances from the Martian rock.)

If we want to see Martian seas in less than tens of thousand of years using H-Bombs (or asteroid impacts) is pretty much needed. It just takes too long for the warmth to work its way down thru the rock and permafrost to thaw out the ground water in any reasonable amount of time.  (The first few meters thaw quickly, after that it is very slow.)

I learned of another problem that will face terraformers from reading this book. When converting atmosphere from CO2 to O2 suitable for humans to breath, plants will suck CO2 out of the air, (releasing O2). However, when the plant dies it then releases the CO2 (consuming O2) when the material rots. It is not until we get significant amounts of carbon buried in oil and coal deposits that large shifts in the CO2 : O2 ratio will occur. He suggests artificially burying peat and wood to speed the take down of carbon from the air. (Or peat and wood could be shipped to the tops of mountains as this is effectively in space and outside of any likely biosphere.) I had understood in principle this problem, but I had not realized the scale of the process.

Some of the ideas that people have given in this book are mind blowing. One engineer, Paul Birch, suggests a series of 3 giant mirrors to focus 1.2 times the normal Martian sunlight into a region only 30 km or so in width. This is enough energy to melt the crust releasing all the volatiles needed. (The set up of all of these mirrors and / mirror - lenses is truly clever. The light pressure from one set of statites is enough to hold up the second set against the Martian gravity while the third floats on the gases released by the boiling crust.)

In summary, this is THE book on terraforming. Anyone seriously interested in the subject should track down a copy. 5 out of 5 stars.

Note:
A lot of what is in this book is in Robert Zubrin's "The Case for Mars". If you don't want to spend $300+ for this book, "The Case for Mars" will give you 85 to 90% of what is in this tome for $15.00.

I have a suggestion for the activists amongst us: we could start a campaign to encourage an updated version of this text. With enough pre-orders we might be able to get a second edition printed with a couple thousand copies. I would be willing to buy a 4 copies of an updated text at $30.00 or so for donating to friends & local libraries.

Dr. Fogg has a website at:

http: www users globalnet co uk ~mfogg

if you are interested.  It is a fairly small site.

Warm regards, Rick.

Hi everyone,
The URL below suggests that melting CO2 clathrates can form brines which will stay liquid at Martian surface conditions. The URL is here:

http: www lpi usra edu meetings lpsc2001 pdf 1689 pdf

I think that clathrates (CO2 'dissolved' in ice) are a significant store of CO2.  If we can warm the planet, this extra CO2 will slowly flow into the air helping the green house warming.

Warm Regards, Rick.

Hi Tholzel,
My understanding was that the theory was that there was frozen H2O  permafrost, with liquid CO2 buried under it at enough pressure to be a liquid.  If something caused the solid cap to break or vanish, the liquid would explosively boil.  The vast amount of heavy gas lifting rock and sand would flow like a pyroclastic eruption, carving the channels that we see. 

I doubt it however.  The distances that the catastrophic floods covered seemed far too great for any sort of CO2 pyroclastic flow.

The White Mars theory was concidered pretty exotic, but it allowed channel type landforms with out resorting to liquid water.  However, in the last 5 or so years Mars is proving a lot wetter than people expected.

This is not direct evidence that White Mars is wrong.  But many people see less need to invoke it given that water is so common.

Warm regards, Rick.

The question origionally asked was "how long it would take for the Greenland ice cap to melt if all the power from the sun when into melting the ice in Greenland?"

To answer it I thought about what would happen if you put all the energy of the sun into a maser beam and fired it at Greenland.  Obviously it would flash to plasma almost instantly. 

However, (as I stated explicitly in my prelude to the calculation), the question of how long would it take with all the energy hitting the Earth from the sun to melt it tweeked my interest.  So I worked it out.  My calculations showed I used the area of the whole Earth's silhouette for the amount of energy absorbed.  This is certainly no secret.

Actually I didn't choose that temperature, I was quoting nickname.  He has not said where he got that figure.  Perhaps it was chosen as a high value which the Greenland area is unlikely to reach?