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The cause of today's thin atmosphere is that it failed to establish about 1 bar atmosphere because of lowering volcanism over time, instead it had only 0.07 bar atm. from the begining that did not have enough strong ionosphere that would protect that atmosphere when the mag. field collapsed.
Hi mlomg, everyone.
Where did you see that Mars started with 0.07 Bars? When the solar system formed, the Sun had 70% of its current output and it is very hard to understand how Mars seems to have been warm and wet for its first billion years or so. I've read that they think that Mars started with about several Bars of mostly CO2. "Mars a Warmer Wetter Planet" page 103. Elsewhere I've read discussions of about 3 Bars of pressure at the planet's birth.
Warm regards, Rick.
Hi Everyone,
nickname, if you think about it, it's pretty impractical. Let us say that you have a big 1 meter wide opening and a turbine so that it will suck a cubic meter of air thru that gap every second. This needs to be filtered, and then moved over the condensers slowly enough to let all the water condense out. That means that there will be a LOT of condensers or that the air will have to be compressed. (If it is compressed it will be warmed of course.) You could have one set of condensers cooling the air while the next set is getting a bunch of compressed air. Then have some sort of vent to switch over each half cycle.
This all sounds big, heavy and not particularly reliable. A space probe may will have to make due with a smaller turbines, etc. so you wouldn't be able to pass 1 cubic meter per second. Assuming you can get a cubic meter per second then 2 billion seconds is well over 6 years. That will take a lot of power. Will it keep working that long? In practice you won't get 3% H2O year round. Also, you won't get 100% of the wisps of water vapor. I would guess that you would be lucky if you could do it in 12 or 15 years. Far easier and more reliable to just ship 6 tonnes of Hydrogen to Mars.
A billion is a really big number.
Antius, they worked out the numbers and this system means that you can ship methane to Mars rather than pure hydrogen. Shipping pure hydrogen means that you have to worry about the reliability and mass of high pressure tanks and cryogenic cooling. Methane under modest pressure will easily liquefy using moderate cooling in space or on Mars. Also, no matter how cold you get hydrogen, 15 percent of it will boil off in space so you have to ship that much extra. The numbers say that slightly more mass will be taken by this system but it will be much more reliable. This is why NASA is planning to use it for their sample return mission.
Warm regards, Rick.
Hi naitsabes, everyone.
Cosmic rays are not stopped by our magnetic field. Some of them are stopped by the Earth's atmosphere.
If we give Mars a 1 Bar atmosphere it will be better at stopping cosmic rays than Earth's is because it has a greater scale height (so there will be more matter there for a given pressure).
Our magnetic field does redirect the solar wind to the poles but Eskimos are not dying of radiation poisoning despite the Aurora Borealis . Mars atmosphere is enough now to protect us from solar particles except during the biggest solar flares. During those astronauts can go into their storm cellar. Once we thicken Mars' atmosphere, this won't be a problem.
As for sustaining the atmosphere, the solar wind causes 'sputtering' on Mars which strips away light particles faster than if it did have a magnetic field. However this happens very slowly: a one km diameter comet would last tens of millions of years. If we thicken the atmosphere with volcanic eruptions or dropping comets to a Bar pressure, it will last for billions of years.
Warm regards, Rick
So you're arguing that a carbon tax should not be done because it might only slow ground carbon emissions by 5% instead of 10%?
I don't care. A 5% reduction is better than nothing. Human beings are causing the 6th great extinction event in the history of the planet Earth.
People, you need to understand this: human beings are a high level predator. High level predators do very poorly when ecosystems crash. By that I mean, very seriously, species extinction.
The human race NEEDS to become experts on planetary engineering and biological manipulations. We HAVE to if we are going to survive. There is no better place to do so than on Mars. And if we get to Mars for 300 years or so then, technology has to crash on two planets.
And people, having technology crash would be very bad. We would lose more than 6 billion people and you can't imagine, no one can imagine how bad that will be.
And societies do crash when they over run their environments. Read "Collapse" by Jerad Diamond, I beg you to do this. If I have earned any respect from you, go to the library and borrow this book. Societies live within their environmental carrying capacity for centuries no problem. They go a bit over. No immediate problem. The population builds up, the society gets bigger, richer, more productive. Culture and the arts flourish. Religions become wealthier and more elaborate. To the average person things have never been better. Some people, maybe, are worried about soil erosion and falling aquifers and dumb things like that. But most people don't care.
And then in an eye blink of the life of the civilization, some disaster gets out of hand and it all collapses. 90% or more of those people die or flee. And that civilization is gone. But WE have a global civilization with 6.5 billion armed people.
Global warming is not going to flood your home in the next 30 years. But it will cause drought, disease, wars and famine. Millions of starving, angry desperate people will be on the march.
And please people understand, we won't get to Mars when India is losing millions of people because the Himalayan snow cap is gone and Pakistan and India are throwing nukes at each other over water rights.
Perhaps many American's don't care too much about glaciers retreating in the Himalayas? Then they should be concerned about the Ogallala aquifer which stretches from South Dakota to Texas. This giant, underground lake has been filled with tens of thousands of years of precipitation and ice melt. It is being pumped out 100 times faster than it could ever refill and when it goes empty the central USA will revert to desert.
Right now the rule is the corporation with the biggest pump gets the water. It could be going empty in large areas in 60 years. Above ground rivers depend on it and will dry up. The bread basket of America will turn into a dust bowl then a desert. (We have not been getting droughts since the 1930's because of Ogallala.)
Will we be talking about Mars missions then? We need to get to Mars now when we are rich. High technology creates wealth. The people on this site know that Apollo paid for itself many times over from technological spin offs.
We need to do ANYTHING we can to buy time. We need to get our politicians seriously, SERIOUSLY, concerned about the environment. And they NEED to fund science and technology and space exploration. And, god help us, we need to have the public well educated on science and technology.
This was all done in the '60s and the USA had gigantic economic growth (mostly squandered on the Vietnam war.)
Global warming, ecological disaster and getting to Mars are all related. We won't get the last one if the other two are beggaring us. And I, truly, think that we need to get to Mars if the human race is going to last another 5,000 years.
The Ogallala Aquifer Depletion.
Williams May Dry Up without 4000 ' well.
Human beings are causing the Earth's 6th major extinction event. This fact should scare all of you.
Sincerely, Rick.
APPENDIX: Another cost of the Vietnam War.
Dr. Robert Zubrin writes:
"I quote from formally classified documents obtained under the freedom of information act in 1997 by Alan Wasser of the National Space Society, published here for the first time. In one of these documents, a December 9, 1966, letter from Assistant Secretary of State Henry Owen to National Security Advisor Walt Whitman Rostow, Owen states:
<Quote:>
Walt:
1. Here are two copies of the final draft of our space paper, as it is being distributed to members of the Space Council - McNamara, Webb, etc. The Vice President wishes it to be discussed in the Council.
2. It will encounter strong opposition from NASA and Ed Walsh {secretary of the Space Council}. I believe it is right, for two reasons:
(a) Moving forward to a more cooperative relation with the USSR in this field will reinforce our over-all-policy towards the Soviets.
(b) More importantly: It will save money [emphasis in original], which can go to (i) foreign aid, (ii) domestic purposes - thus mitigating the political strain of the war in Vietnam.
3. If the proposals in this memo are left to be fought out by the space marshals and their clients, we will lose. Therefore:
(a) I urge you to get in the fight personally - let the Vice President, Schultz (BOB), and others know how you feel.
(b) Send a copy to someone on the domestic side of the White House staff (feel free to use this covering memo, if you wish) to ensure that someone from that side, representing the constituency whose interests are most directly affected, gets into the fight.
Henry Owen
<end quote.>
Zubrin's book discusses further how NASA was dismantled behind the public's back, the outer space treaty and other outrages.
pg 12 to 13 from "Entering Space: Creating a Spacefaring Civilization" by Dr Robert Zubrin.
The hope that savaging NASA's budget would help offset the cost of the War failed. Note that NASA spent $25 G on the whole Apollo Program. The Vietnam war spent $0.5G / DAY for years.
I wonder why a condenser isn't thought about much in the fuel schemes.
Hi nickname, everyone.
The reason is simply the extremely low vapor pressure of H2O in
the Martian atmosphere. In order to get that water you have to
cycle a huge amount of air. This requires big air intakes, fans
etc. Remember any moving parts are a weak point because of
the ultra fine dust.
In the reactors Dr. Zubrin is planning, a small hole is opened
and CO2 enters the reaction chamber after going thru a dust filter.
It is sealed off and the gas is processed. Repeat as needed. No
blowers, compressors, etc. are needed.
Let me work out the math. The percentage of water in the atm
ranges from about zero up to 0.03%. Let us say that you want
6 tonnes of Hydrogen (enough to power the Mars Direct rocket).
Now water is 2/18ths hydrogen by mass. So you would want
6 tonnes / (2/18) = 54 tonnes of water.
So if you take a cubic liter of Martian air. I don't know what this
would mass but I can approximate this from the Ideal Gas Law.
(Basically take CO2 at standard temperature and pressure and
lower the temperature and pressure. (Any one know the exact
mass of a liter of Martian air?)
Anyway, using the ideal gas law my approximation for the
Martian air is 0.0045 grams / liter (of this near vacuum at 6mBar).
Since only 0.03% (at best) of this is H2O we need
0.0003 * 0.0045 g / liter or about 0.00,000,14 g / liter of water
in the Martian air. Since we need 54 tonnes of water this is:
0.00,000,14 g / liter / 1,000,000 g / tonne = 1.4E-11 tonnes per liter.
So we need:
54 tonnes / 1.4E-11 tonnes / liter = 3.9E12 liters of air.
Since 1,000 liters are in a cubic meter we will need to blow
3,900,000,000 cubic meters of air thru the condenser (assuming
the condenser is 100% efficient). Call it 4 billion cubic meters.
I just thought, I was using the minimum air pressure. If we
assume that we do this when the Martian air pressure is at its
highest, then we would need about half the volume that I
calculated above. (But the dust would be worse then. You
will have to make sure you don't get dust in your condensers.)
I'm making some estimates here so I wouldn't be surprised if
I'm off by 10 or 20%. But the point is that you would need a
LOT of blowing and compressing to get any reasonable amount
of water out of the Martian atmosphere.
Warm regards, Rick.
This is from the Pioneer Astononautics website:
"Although all the compounds listed in Table 1 are usable as high quality fuels, their potential as feedstock to plastic production processes should be briefly mentioned.
Ethylene has been called the key to the plastics industry. In terrestrial applications, it is the precursor for many different varieties and grades of polyethylene, which is the most widely utilized plastic in the world.
Propylene is the precursor for polypropylene, which is the second largest volume commodity terrestrial plastic at this time and is widely used for textiles.
Toluene is not directly used as a plastic monomer, but is usually converted to benzene and/or directly combined with ethylene or propylene. With various further processing steps, these chemicals end up in products as diverse as polystyrene, styrene-butadiene rubber, Nylon, polyurethane, epoxies, aspirin, and explosives.
While these applications will be irrelevant to robotic and early human missions, they are potentially very valuable when it is time to build a permanent outpost on Mars."
see:
Use of Aromatic Hydrocarbons.
Nice to see Dr. Robert Zubrin's company is still working towards the Mars colony.
Warm regards, Rick.
Assumptions: ...
Human beings consume ~2500 calories per day in food energy, which equates to 1,000 kWh/year of food energy.
Hi Antius,
I checked this. ~2,356 kilo calories / day almost exactly equal 1,000 kWh/year. (Workings shown below.) Close enough for government work.
I did more research and Bios 3 was a life support experiment in the USSR. It did not get to the stage of being a closed biosphere but it did recycle 30 to (eventually) 70% of the crew's food. They eventually reached 6 month duration before trace element loss became a major concern. Anyway this was not a theoretical ecosystem, it was an actual experiment.
Some more from Fogg:
(pg 52) "Realistically, it seems that such systems may always fall short of the ideal, simply because it may be impossible to scale down the volume of the Earth's biosphere by a factor of >10E13 and adequately maintain all its functions. ..."
(pg 54) "Another consequence of low volume is that the dynamics of the contained biosphere are poorly buffered. This means that the biota are connected with a much smaller reservoir of biogenic materials than on the Earth. Such materials therefore, as a proportion of their abundance, have to cycled through the biota at a much faster rate. ..."
He goes on to describe how Biosphere 2 had to cycle ALL of its CO2 in just a few days. There were 600 ppm variations in CO2 between day and night. He goes on to say,
(pg 54) "... This faster pace of change has the effect of making the system intrinsically less stable. Minor imbalances significantly affect the composition of the buffer in a short period of time. Any habitable equilibrium must therefore be extremely precise as these imbalances could run away very rapidly. The less-than-total predictability of the dynamics of the ecological systems may make achievement of such a fine balance very difficult, especially as natural stabilizing biotic responses that function with in the vast and massive biosphere of the Earth may be too slow or inoperable in a confined space. Once the buffer has changed to the extent that the biological function is endangered (e.g. by levels of CO2 falling too low or rising too high) the system is in danger of crashing completely."
(Emphasis his.)
He goes on and discusses all the tasks that technological life support must do that we get for 'free' from our biosphere. (This cost is measured in energy consumption.) For example, Biosphere 2 had to pay energy for:
- External structural maintenance teams.
- Fans to circulate air.
- Temperature regulation system.
- Dehumidifiers in basement air coolers.
- Pumps to circulate water.
- Misting machines for 'rainforest' cloud.
- Desalination system to maintain fresh water reservoir.
- Algae scrubbers to transfer water between 'salt marsh' and 'ocean'.
- Wave machine to oxygenate 'ocean'.
- Soil bed reactor to neutralize trace contaminants in air.
- CO2 scrubbers (unplanned).
- Emergency oxygen injection system (unplanned).
- Compost machine for rapid recycling of inedible plant waste.
- Monitoring systems.
In Table 2.6 he lists human power consumption & compares it to Earth and contained biospheres.
EARTH (WITH GRATIS LIFE SUPPORT)
------------------------------------------------------------------------------------------------------
World average primary power................................~ 2kW / person
World average electric power.................................~0.2 kWe / person
Industrial nations primary power............................~6 kW / person
Industrial nations electric power.............................~0.7 kWe / person
EXTRATERRESTRIAL ESTIMATES:
------------------------------------------------------------------------------------------------------
EC/LSS only (stored food).......................................~2 kWe / person
Stanford Torus Space Settlement...........................~3 kWe / person
CELSS only (hydroponics w/ fluorescent light)......~15 kWe / person
Ohbayashi Mars Colony 2057
(Total power for all activities)................................~50 kWe / person
Biosphere 2........................................................~100 kWe / person
Quoting Fogg again:
(pg 58) "A particularly worrisome feature about table 2.6 is the power consumption of the one working model of a biosphere habitat, Biosphere 2, which requires a huge ~100 kWe / person to operate, ..."
(Its power requirements were so great that they had to build a power plant on site to pay for this energy. The electrical energy was actually ~1/2 that which was supplied by the sun over its area.)
He then goes on to point out that larger ecological containers than Biosphere 2 will not have to pay all these costs. If you have a big enough biosphere that you have a natural weather cycle you don't need to worry about wave machines and weather simulators for example.
Anyway, this is food for thought.
Kim Stanley Robinson has written a novel called "Icehenge" where a key plot point in the early part of the book is the difficulty in closing a life support system. You might find it interesting.
Warm regards, Rick.
Math Appendix:
// Human beings consume ~2500 calories per day in food energy,
// which equates to 1000kWh/year of food energy.
Checking this:
You say that humans need ~2500 calories / day. These are of course, kilo-calories. 1 k Calorie = 4,184 Joules.
So 4,184 J / kCal * 2,500 kCal (per day) = 10,460,000 J (per day)
1 kWh= 3.6e6 J (a kilowatt hour is a measure of energy so this is correct).
(Power = energy / time so: power * time = energy)
10,460,000 J (per day) / 3,600,000 J/ kWh = ~2.91 kWh (per day)
2.91 kWh / day * 365.25 days / year = 1,061 kWh / year
So:
2,500 kCal / day / ((1,061 kWh / year) / (1,000 kWh / year)) =
= 2,356.27 kCal / day
Hello Rick,
...(2) Basic photosythetic efficiency of algae in natural sunlight is ~5%...
The second problem is the instability of small ecosystems. From what you have told me, large ecosystems tend to be more stable because the massive volume of air serves as a buffer against any sudden changes in atmospheric gas concentrations.
Hi Antius, everyone.
That 5% figure sounds wildly optimistic. Do you have a reference for it ?
EDIT: The figures I was thinking of were discussing conversion of light into biomass on Mars and NOT talking about the efficiency of photosynthesis itself. I have been doing some research and 5% seems totally possible for algae. (Natural ecosystems usually run from 0.5% to 2% efficiency. I could easily see some species of algae reaching 5%.)
As for the stability of ecosystems, Fogg was not saying the air volume was the key problem. He was suggesting that small ecosystems were less stable than large ones. I think that he picked the air volume to biomass ratio because it was something he could use even for theoretical habitats since they had published their volumes and the size of the biomass could be estimated.
But, if your air is going out of whack, it is nice if it has enough volume to buy you some time to fix it.
Warm regards, Rick.
People will not need greenhouses to produce food. Microscopic water-bourne plants (algae), yeasts and edible bacteria can produce food that is as nutritious and tasty as that which we enjoy today. This can be done using artificial energy sources and the plant required is extremely compact and will not need any sunlight.
Human beings will live within compact settlements, under pressurised plastic domes. ... <SUMMARY: UV, cold & vacuum won't be an issue.>
At no point will a terraformed planet be neccesary for survival. ...Pluto would be every bit as colonisable as mars, in terms of environment and resources.
Hi Antius,
Bacteria and yeast are anaerobic so if you want oxygen you need photosyntheses. And photosyntheses whether done by crops or plankton is very inefficient. It requires a gigantic amount of energy. I consider it, very, very likely that people will take advantage of the free light from the sun to reduce this energy cost. So unless you postulate that the energy is so cheap that it is not worth building windows then I think we will have greenhouses.
You might want to read "Terraforming: Engineering Planetary Environments" by Fogg. In Chapter 2 he looks at the stability of closed life support systems. Basically he shows that the larger the ecology, the slower it reacts to permutations. I reproduce a chart from page 55:
BIOMASS TO ATMOSPHERE MASS RATIO (Normalized so Earth will be 1:1)
CELSS "Breadboard"........................................... 2000:1
Bios 3.................................................................. 1000:1
Biosphere 2........................................................... 350:1
Stanford Torus....................................................... 250:1
O'Neill Island 2......................................................... 20:1
Bernal Sphere.......................................................... 13:1
Martian "Worldhouse"................................................ 7:1
Earth......................................................................... 1:1
Terraformed Mars....................................................... 1:2.7
All of the above are theoretical except the CELSS "Breadboard" (which failed) Earth (working) and Biosphere 2 (which failed).
The only stable biosystem we know of is Earth. Biosphere 2 is the largest attempt to build an independent self sustaining biosphere and it was wracked by instabilities and problems. The food plants produced too little food in part because they overestimated how much light they would get from the desert sun. Carbon dioxide production (by animals) so greatly exceeded the production of O2 by plants that carbon dioxide scrubbers had to be installed. (Another reason for low food production was that broad mites were not properly kept in check by predators and ate too much of the food.)
There were many other problems with Biosphere 2 (concrete absorbing CO2, biological matter rotting and absorbing O2, air conditioning problems in keeping this giant green house cool, etc.) It makes very interesting reading.
I consider Biosphere 2 to be a huge success as an experiment. It showed just how hard it is to create a independent biosphere. We should respect the one we have; it is precious and very rare.
If we postulate that you have very, very cheap power and a perfect biosphere that does not need sunlight (so it works equally well underground or on Pluto) then your point is made. However, I expect we will have largely terraformed Mars before that happens. You feel that a closed ecology is easy to create; I don't. Perhaps we should agree to disagree?
Furthermore, a plant sized biosphere is attractive for more reasons than just aesthetics. In a small colony with a high power life support life is totally dependent on technology. One dark age will end life. Tiny life support systems will also concentrate political power. You will have 'hydraulic empires' unlike history has ever known.
So in answer to your original question: "Terraforming - Worth the Effort?" I think the answer is yes, at least until we see a Biosphere 2 or something that is able to close the ecological cycle. I LIKE ecosystems that are independent of technological intervention.
Warm regards, Rick
"On to Mars - Colonizing a new world" edited by Dr R. Zubrin & Frank Crossman of the Mars Society, Apogee Books Space Series, (c) 2002, 264 pages, $19.95.
This is a book that has a series of monographs on topics brought up in the Mars Society annual conference. It includes a CD with more papers from the 2001 and 2000 conference as well.
I had put off writing this review for a long time hoping to read thru the CD and including comments on it. However, I've been so busy that I've decided to just review the book. When I get around to the CD I'll edit this post.
This book did not have anywhere near the impact on me that "Case for Mars" did. But "Case..." had many clever ideas that had been built up for many years by many people all presented in one place. This book is incrementally building on that work (so to speak). Filling in details and offering opinions of the details of colonizing Mars. There is not much new on Terraforming.
As can be expected, the articles are of varying quality. Some I found very interesting; others I had to force myself to finish.
The greatest value of the book is the data that it contains. For example, in the article entitled "Power, communications and Computer Technologies for Mars" they give numbers for geothermal, nuclear, solar, solar power satellites and wind power, specifically working out which would give the most power per stowed volume. This is info you would have to search long and hard for elsewhere.
Others were what I considered puff pieces. Clerics saying if you didn't bring priests and God to Mars then it was not worth going. They were very careful not to say which religion they supported so the reader is free to assume that it is the one that they favor.
There was a wide variety of essays. From funding options for Mars exploration, legal considerations, details of potential colonies, types of space propulsion systems, crew selection, vehicles for the Martian system, ethical considerations of terraforming, and ideas for making the Mars society more successful, there are many ideas and topics.
One eye opening essay said that the first person to land on Mars, stay there a year and come home should OWN it. It sounds preposterous, yet the author makes a strong case for this.
The book is likely to have something that will interesting for anyone curious about Mars exploration and terraforming. It is written at a variety of levels (some assume a solid science background others are for anyone). A few of these articles tempt me to summarize them for our terraforming forum.
The book's opening is a speech by Robert Zubrin which brought tears to my eyes. This is a man that knows how to make people think big. I'm tempted to recommend people buy the book for that speech alone.
However, I think that only real Mars fanatics will want to buy this book. For normal folks, you might suggest that your local library pick up a copy.
Warm regards, Rick.
If the planets at trojan points were not of comparatively negligible mass, but on a par with the other planets, would the system still be stable?
I think so, I believe it is called a Rosette World.
It is not stable. If the mass of the body at the Trojan point is more than 4% of the smaller of the two primaries it is unstable to outside permutations. The Rosette world is stable in a system with no other bodies but is unstable in the long term if there are any permutations to the orbit.
Warm regards, Rick.
Hi everyone, Rhodes.
Rhodes, if you gave us more background for WHY you needed the O2 it would be easier to help you. Yes you could ship acid to Mars but shipping anything to Mars is very expensive. If you are shipping people to Mars they will grow plants and O2 will be generated from water using sunlight.
If you want rocket fuel, then ship a nuclear reactor plus some hydrogen to Mars and use its heat and power to make aromatic hydrocarbons (benzine and like products.)
There is more information here:
Using Aromatic Hydrocarbons for Mars Mission.
The key equation is:
6 CH4 --> C6H6 + 9 H2 + heat
Why not ship the Hydrogen directly rather than methane? Hydrogen has such a low boiling temperature that 15% of it will boil off en route. It is expensive (in terms of mass) to handle it and cool it. It would require less mass to hold on to a tank of CH4 (which readily liquefies at spacecraft temperatures under moderate pressure) rather than H2.
The hydrogen is what we want. It is reacted using the Sabatier reaction with CO2 thus:
CO2 + 4 H2 --> CH4 + H2O.
The methane is used as fuel with O2 split from the water. The H2 released from the water is used to make more methane.
Or you can heat the CO2 in hot H2 in the presence of a chrome catalyst:
CO2 + H2 --> CO + H20.
The carbon monoxide is vented as a waste or could be used as a very useful industrial chemical if your economy has gotten that far. The water is cracked into H2 and O2. (The reason we don't just dig up the rock hard ice and use it directly is that it is easier to build an automated chemical processor that uses the air than creating a mining unit.)
You should look at "The Case for Mars" by Robert Zubrin in your library.
Warm regards, Rick.
We all depend upon technology to survive - for water, food production, shelter, transport of goods, waste treatment, etc. Without that technology, life for most of the human race living today, would be as impossible as it is on the moon.
But this largely misses my point. My point was, that by the time we get to terraforming Mars, it will already be heavily colonised by human beings who:
1) Do not need a terraformed planet in order to survive;
2) Do not wish to endanger their environment with the sort of massive global changes that terrforming would entale;
3) May have everything that they really want and need within the boundary of their habitats. ...
Hi Antius, everyone.
I agree with what you say about us requiring life support now. I also agree with point 1 above.
But as for 2, my question is "what environment?" If there is no life who cares about the Martian environment? The solar system is filled with lifeless rocks. After you have spent a few years in a lifeless environment, I suspect that giving Mars a biosphere will look pretty darn attractive.
As for your #3, the reason will be many people will want a world that won't kill their kids at a drop of the hat and there will be economic incentives to do so.
Mars is so cold it is dangerous and expensive. If we add greenhouse gases it will warm up making it cheaper to live.
Mars is a near vacuum which is dangerous and expensive. If we thicken the atmosphere it is safer and cheaper to live. Greenhouses in particular get a lot cheaper if Mars is not a near vacuum.
Mars has so much UV that it is dangerous and expensive to protect against. If we add a small amount of O2 we get an ozone layer for radiation protection.
Now all of these steps run into the free rider problem, but it could be argued that the free rider problem is the real purpose of governments. It is true that terraforming is so long term that it will always seem like it is not worth the while. But it is a job that inspires men's souls and I can see people devoting their lives to moving the project forward.
Warm regards, Rick.
... I doubt Venus will obtain it volatiles from a planet 0.16 light years away.
Hi everyone, Tom.
Neptune is 30 AU out, but this is only 1.678e-25 lightyears.
Warm regards, Rick.
...
Then the problem of trying to have 17 times the quantity of sunlight at 20 times the distance from the sun as Earth comes to mind.
That is just to keep the place warm. ...
Hi everyone, nickname.
The situation is worse than that. Neptune is actually at 30 AU from the sun, so it gets 900 times less heat from the sun than Earth and about 150 times too little light for photosynthesis. Plants require a stupendous amount of light to grow so food and air are always going to be very expensive out there.
And this is an expense that has to go on year after century after millennium.
Rick
The main problem with terraforming seems to be an excess of carbon. CO2 seems pretty abundant, as does Hydrogen, so water is no object. The gas giants are made of Hydrogen and Helium so the best planetary transportation would be helium filled airships.
Hi everyone, Terrafomer.
If you wanted to put a dirigible in a gas giant atmosphere, you would have to use hot hydrogen. He is more dense than hydrogen so it would sink.
Warm regards, Rick.
I strongly believe that we need to cut carbon emissions. But you are dead right in that lowering energy consumption is the equivalent to being poor. Our only hope is fission power and then fusion.
There is an excellent essay, in "Power" by S.M. Stirling. It traces the amount of personal freedom people have enjoyed and compares it to the energy density they control. When you have cheap energy you don't need slaves.
But look at how Magnetoplasmadynamic power plants were killed off by current energy interests. Look how funding for fusion has dropped just as we are getting to the point of ignition. It is enough to make one weep.
In the documentary "Who Killed the Electric Car" they point out that the oil companies expect to make 6 trillion dollars in the next decade if the price of oil remains high. (I am not sure of this figure, can anyone double check?) It is a huge amount anyway. If they have the influence to get Bush to launch lawsuits against the California law mandating that 4% of cars sold do not contribute to the air pollution, what chance does fusion have before that oil is burnt and even MORE carbon is in the air?
As for coal, anyone who thinks it is non-polluting should visit the Chinese countryside. It is an ecological disaster AND it pumps ground carbon into the air.
Humans are causing the Earth's sixth large extinction event. We have records of dozens of cultures that have overran their ecological carrying capacity and collapsed. (See "Collapse" by Jered Diamond for an especially easy to read account of some of these civilization leveling disasters.) When I look at what is happening in the world, it is like watching a train wreck in slow motion.
Rick
Altho some have suggested that oil comes from non-biological processes (so Mars might have some) I suspect that oils and hydrocarbons will be rare or non-existent on Mars. The Jatopha plant is a hardy, drought resistant species that produces fruits that are over 1/3 oil.
Facts:
- A fast growing perennial.
- Can live for 50 years.
- Average height is 3 to 5 meters.
- Requires little maintenance.
- Requires 1/10 the water that an average palm tree does.
- Can survive 3 Earth years with no water by dropping its leaves.
- A laxative and has been used to treat fever and malaria.
- Sap is an anti-inflammatory.
- Seeds have 37% oil content.
- Produces oil in its second year and can live 50 years.
- Bark and twigs can be made into ink, tannins and dyes.
- Oils in seed can be used for bio-diesel fuel, soap, candles & lubricants.
- Prefers well drained soil.
- Does require high - quality soil.
- Thrives in warm temperatures.
On Earth the plant is used to prevent erosion, create a living fence that livestock won't eat and to repeal rodents. It grows wild in Central and South America and Africa.
The main problem of course is that this plant prefers a warm climate which means it will likely be a green house plant. However, I think it likely that it will form an early industrial crop.
Warm regards, Rick.
Simply coating the rocky core with Iron (or Nickle, if it's magnetic) would make a magnetic field.
Hi all, Terraformer.
Nickel is a magnetic metal. However, a cold iron or nickel will not make a magnetic field. What you need is flowing conductor (such molten metals, flowing metallic hydrogen or salty water). As this flowing conductor moves thru the sun's magnetic field the dynamo effect will induce currents which will then form your magnetic field.
Rick
Are there any estimates of temperatures, pressures and weather atop the plateau, mid-wall and down in the Valles Bottomlands ??
This is a very tricky question since the answer depends on what the conditions of the MEGAOUTFLO event leave the planet. The scale height of Mars is 11 km so everytime you go 11 km above the datum, the air pressure drops to 1/e what it was at the datum. 5 miles is about 8 km so assuming that the floor of the Valles M. bottom lands are close to the datum (likely a good guess) then the air pressure at the top would be about 27% as thick as at the bottom.
Guesses were that early in Mars' history it had a CO2 atmosphere around 3 bars. This would mean that at the top of the rift valley would have a pressure of around 1 bar.
Most of the MEGAOUTFLO events took the average temperature of Mars up to a few degrees below zero. However Valles M. is near the equator, at low attitude and so would expect near the maximum warming. As a wild guess I would venture that perhaps 1/3 of the year's days it would have temperatures topping 0. So you would expect a lot of water running under frozen surfaces or glaciers. Further up the walls there would be frost, ice and water under permafrost. (Back then Mars' ground was a lot warmer...) Expect glaciers everywhere.
Similar question applies to Terraformed Mars. Assuming enough cometary imports to raise atmospheric pressure to 'flowing water' for a few millenia, enough greenhouse gasses to thaw those caps...
Will Mars be 'Out Of The Silent Planet', with 'High Plains' / Andean Plateau conditions in Marineris and 'Everest' everywhere else ??
What's the lapse rate ??
The questions above are unanswerable because it is anyone's guess at how far terraforming will proceed. My gut feeling is that terraforming can takes us with out too much trouble to Andean Plateau in the low laying areas. But it will take a lot more effort to make the high lands places where Earth animals will survive. So (my guess) is that the low, equatorial areas will be like the coldest areas on Earth and the higher areas will be left to the lichen and glaciers.
Lapse rate: The estimates are that MEGAOUTFLO events die out within millions of years after the volcanic eruptions that created them stops.
Warm regards, Rick.
This made me think of using a mirror array (made up of many individually movable mirrors) on the surface of Mercury to achieve the same job [focusing heat on Jupitor's moons]. ...
Perhaps each segment can be built on the cold side and transported around to the hot side when completed.
Hi all, Michael.
The mirrors will be sending the light typically 930 million km. To create a mirror with a focal length with this precision will require the reflecting surface to be optically smooth at the sub-atomic level. These giant mirrors will have to flex to keep the moons in focus. They will have to adjust for the heat causing them to expand and change the focal length, etc. I don't see it being physically possible.
Mercury does not have a cold and hot side. It rotates 3 time every two orbits.
Warm regards, Rick.
Several years ago I read a Scientific American article that talked about ways carbon moved from the ground into the biosphere / atmosphere. The major ways that carbon moved into the ground was:
- carbon rich sediments being subsumed under continents via continental drift.
- The weak acid (carbonic acid) weathering rocks and being incorporated into mineral sediments.
- formation of calcium carbonate in shell fish and coral (which is buried and eventually turns into limestone).
- vast shallow swamps having ferns dropping into them, forming coal beds. (Not happening now.)
The point was these carbon sinks take millions of years to remove the carbon from the biosphere / atmosphere.
It is widely quoted that a carbon atom in the atmosphere will take a couple hundred years on average before it is incorporated into the biosphere. However once the carbon is incorporated in the leaf of some bush, the problem is not finished. In a few years that leaf will die and rot and the carbon will reenter the atmosphere as carbon dioxide again.
The carbon that is being pumped into the air will be around for a lot longer than a couple centuries. The key point is that it does not have to be removed from the air since most carbon sinks that remove it from the air will send it back into the air a few years later. The question is how long will it take to move the carbon from the air / biosphere BACK INTO THE GROUND. This will take a lot longer.
Ground carbon (fossil fuels) have such a high energy density that they will be in demand until they are exhausted. I think that anything that lowers their demand will be needed if we hope to save the planet.
We might try to cool the Earth with giant mirrors. But if the danger of thinking of this as a quick fix is that if civilization ever drops below the space flight level, who keeps the mirrors going for thousands of years. Remember these will be constantly accelerated from light pressure and the solar wind. Giant mirrors will be affected by tides tending to pull them vertical. Giant mirrors if made out of metal (say an aluminum layer over plastic) can have currents induced in them as they move thru the Earth's magnetic field. Once they have induced currents, then they will be affected by those self same magnetic fields.
Basically I can not see such giant mirrors staying in a stable orbit for hundreds of years with out active measures to do station keeping. And this then makes the health of the entire planet based on human kind maintaining a high tech society.
Rick
Hi Everyone.
I read this article and the main thing that struck me is that the chance of NASA increasing the cost of the mission many fold to make the area around their astronauts a bit warmer just won't happen. But for the terraforming forum this data is great.
I was really surprised that they found that 9% of the sunlight was scattered by the atmosphere. With Mars air pressure being a near vacuum, I would have guessed a much lower number.
The reason they use convex is because they want to inflate them with a gas charge. They make up for the spreading of light with additional mirrors. I think that they are trying to make the mirror as flat as possible given how they hope to deploy it.
Thanks noosfractal for bring this to our attention!
Warm regards, Rick
So a strong CO2 atmosphere and sulfur in the regolith will add to acidity, keeping it well below 4.0. Remember sphagnum grows between pH 3.0 and 4.5, stronger acid decomposes rock flower more quickly; I said the goal was 3.0 to 3.5.
I don't think we need to panic about the peat moss (to be used as soil expander) being acidic. The plants are pushing H+ ions into solution, a good number of them will be left behind in the water when we pull the moss out and dry it. When we mix the moss with regolith the hydrogen protons will react with clays and the minerals of the regolith and speed getting minerals out of the rock into forms plants can use. Also note that there are many species of plants that will grow in some what acidic soil. (Rhododendrons for example.)
Someone who knows more about botany than I might suggest some useful Mars plants that prefer moderately acidic soil.
Anyway, my point is that acids are not like some bacteria that grow and spread. If the soil is somewhat acidic, the protons will react and the soil will become less acidic unless the plants keep pumping protons into it some how. (Fir trees drop needles which make the soil around them more acidic in part to cut down on competition.)
Warm regards, Rick.
Look up the term aeroplankton. Wikipedia often has a lot of information, their definition:...
Hi RobertDyck, everyone.
Wow, I had never heard of aeroplankton, thanks for the tip. The universe is just so strange. Wikipedia actually has very little on them, how often are they found at the top of the stratosphere? Do you know any books that talk about their life cycle & ecology in detail?
However, despite being proven uneducated on this element of my argument, I remain unconvinced that it is simple to terraform Venus. You talk about gene-engineering terrestrial bacteria; all DNA requires phosphorous. This is not found in Venus' upper atmosphere in any quantity. (I've never seen anything that says it has been detected there at all.) That is saying nothing about the other trace elements that you need to make cells.
Spatula, the temperature on Venus' surface is ~465C which will melt lead. This is above the critical temperature of water (374C), where no matter what the pressure it is at it does not form a liquid. So there will be no water to dissolve CO2 and do the other things you mention. The water in the atmosphere, will photo-disassociate and the hydrogen will be lost. I believe I've read that NASA space probes have detected hydrogen being lost from Venus. Anyone have a link?
Spatula, what do you mean 1g/L?
Antius, when the sun was only 70% as hot as it is now, Venus was thought to have a hot wet greenhouse. The temperature then was enough to evaporate the seas. The carbonates were baked out of rocks releasing CO2 and Venus has turned into the dry greenhouse it now is as the hydrogen was lost.
Now if we add water (which is a VERY powerful greenhouse gas) we make the temperature problems worse. If we could somehow turn the CO2 atmosphere into oxygen then Venus will then radiate a lot of its heat and we might be able to get it to a stable state. But for that to happen, you have to have liquid water at the same place as the phosphorus, iodine, iron & other trace elements. I don't see this happening unless the planet is made much cooler, presumably with some sort of space mirror or the like.
In the book, "The Life and Death of the Planet Earth: How the New Science of Astrobiology Charts the Ultimate Fate of Our World" by Peter D. Ward and Donald Brownlee, they argue that the increasing temperature of the sun has brought Earth close to the edge of long term habitability. They argue that within 800 million years our planet will be sterile.
Venus is a lot hotter than Earth (1.913 times the Earth's insolation), so its oceans will always be in danger of ending up in the run away wet greenhouse that it suffered when Venus was getting 1.33 times Earth's current insolation. This suggests to me that we will ALWAYS want to have a mirror reducing the amount of heat it gets from the sun, or be adding more floating mirrors, manually sequestering CO2, moving Venus farther from the sun, etc. It just sounds like more work than for Mars.
In other threads, people have spoken of magical nano-tech to harvest CO2. Of dropping giant comets to add water to Venus. Of spinning up the planet's rotation to give a usable day/night cycle. Or of moving Venus and Mercury around the solar system, etc. These are obviously very, very difficult to do. I do not argue that it is physically impossible to terraform Venus, just that it is harder than to do so than for Mars.
Anyway, I usually ignore the terraforming Venus / Titan / Europa / etc. threads. They are (I think) very far in the future, where as Mars could be terraformed with current technology, assuming we had a population on the planet. Mars is where my interest lies.
Warm regards, Rick.