New Mars Forums

Hi everyone, X.
  Thanks for the kind words X.  You might ask the local university libraries to order a copy of Mars A Warmer Wetter Planet.  They have significant budgets to order books and the librarians are delighted to get thoughtful requests.  Failing that you could try ordering it on Albris.  I got my copy there very inexpensively.

  I was hoping that someone else would do a review of Case for Mars since likely plenty of people have a copy, but anyway, this book does not deserve to wait longer...

"The Case For Mars: The Plan to Settle the Red PLanet and Why We Must" by Robert Zubrin, Published by Touchstone Books, (c) 1997, 339 pages, $15.00 softcover.

This is THE book on Terraforming that is currently in print. 

Robert Zubrin almost singlehandedly has transformed the idea of going to Mars from a $500 Billion boondoggle to a pratical plan.  (NASA has taken his Mars Direct plan and modified & expanded it but it still will cost less than $75 Billion dollars.)  If we used Mr Zubrin's origional plan we could have humans on Mars in less than a decade with 13% of NASA's current budget.

More than any single person, Mr Zubrin has transformed human thought on the Red Planet in the last 12 years.

This book is a powerful example how ideas can be nurtured and grow.  It has been the single largest recruiting tool for the Mars Society and other pro-space exploration groups.  Encourage your local libraries to buy copies.  Failing that, buy some copies of your own and donate them to all of your local high school's libraries.

In case you can't tell, I am IMPRESSED by this book.  It is aimed at a science literate layman.  Someone with highschool science will have no trouble understanding it.

The book starts off describing the Mars Direct mission.  As an engineer who has worked on real rocket programs, Mr Zubrin knows how to plan what is possible.  He then discusses the history of Mars and space exploration to that world.  Many of the problems with NASA and previous Mars programs are political.  Nothing new there but they are spelled out.  (The worst is the 'cost plus' accounting system used for buying rockets in the USA.  This alone has cost the USA hundreds of millions of dollars in lost commercial launches.)

He then goes over how his "Mars Direct" plan (that he invented with some other engineers at Martin Merrietta Astronautics) would work in detail.  Unlike many space programs that people have suggested this gives the details, showing tonne by tonne how the package will fit together.  His biggest innovation was realizing that Mars' CO2 atmosphere could be used (with a dense power source) to make rocket fuel, reducing manyfold the size of the initial launches.  (By not having to ship the rocket fuel to Mars, the size of the initial launches is reduced as we don't need fuel to launch the fuel.)  A feed stock of hydrogen must be shipped to Mars but thru simple chemistry plus power this is turned into 18 times its own mass of rocket fuel.

He then talks about the "dragons" that scare people into saying that a Mars launch is too dangerous and needs more studies.  He shows that these are  paper tigers.  Just one example is the idea that we need to study long term exposure to zero gravity.  Not only are these problems well understood (needing no further study) but by spinning the spacecraft at the end of a teather, connected to the upper stage of the rocket, the zero gravity can be simply avoided.

He also talks about the alluring siren of the moon.  Many people say we should go back to Luna before going to Mars (this is the current USA plan).  He points out that there is no practical need for a Lunar mission before going to Mars.

Starting in chapter 6 thru 9, he discusses building the initial base, the initial colony and finally the possibility of terraforming Mars.  These section of the book are dense with practical ideas on how we can use local materials to help the people there.  This is the biggest difference between Mars and Luna.  Luna is missing most of the elements that life needs, Mars is a rich planet where the materials we need are there in the air and dust.

Furthermore, Mars has been geologically active with both volcanos and water erosion.  Both of these will concentrate minerals suggesting that we will find useful ores on Mars when we start exploring it.

In the final sections of the book he argues that if we wish to have a free society having a frontier is key.  He suggests that Mars is the only likely frontier our society will have soon.

Then in a late chapter he talks about the Martian meteor ALH84001 which showed signs of life. 

After finishing this book, I turned back to chapter four and read it thru to the end again.  It was that exciting.

This is a book that is dense with ideas. 

Since the book has been published things have moved on.  For example, his company Pioneer Astronautics, has continued to work on Mars enabling technologies.  He has created a superiour SCUBA diving breathing system  which can be used in space suits.  He has also shown that even more mass can be saved by converting the hydrogen feed stock into aromic hydrocarbons for a 54 times increase of mass when converting it into rocket fuel.  Partly because of his continuing work, the cost of the Mars mission has continued to drop since he first promoted Mars Direct.

Our understanding of Mars has also grown since then.  The major things we have learned is that Mars has a lot more water than was thought when he wrote the book (which is good) and that the southern polar cap has about 1/4 of the CO2 than was thought (which is bad).  Terraforming can still be done using his methods, but using the perfluorocarbons (the super greenhouse gasses he discusses) will likely be manditory as well as just the polar solletta mirrors.

The Martian meteor ALH84001 now looks like the indications were NOT caused by life but (in my opinion) this question is not fully resolved.  More than anything that rock has shown how hard it is to distinguish life signs that are microscopic in size.  (If we were on the planet, the problem would be trivial to solve.)

The current Mars Sample Return mission that NASA is building is a direct result of this book and the Mars Direct plan.  Anyone with an interest in Terraforming should snap up a copy of this book.

Warm regards, Rick.

This is a great thread that basically shows that you can't use nuclear weapons to warm Mars by hitting the polar caps.

Martyn J. Fogg had a different idea in his "Terraforming: Engineering Planetary Environments" book.  On page 281 to 283 he suggests non-fission boosted thermonuclear pipes to melt ground water and vaporize nitrate rocks.  Lacking Fission products they would produce little fallout as well as being more powerful than fission bombs.

He points out that the entire nuclear arsenal of Earth (approximately 10,000 megatonnes) is equal to 1/2 an hour of Martian sunlight.  However, there are things that sun light is good at (crops and general warming) and some things it is too dilute an energy source for (vaporizing nitrogen rich rocks and melting quickly deep ground water).

Fogg suggests using thousands of these fusion rods to quickly jump start terraforming.  I think that some mirrors, greenhouse gasses and a several hundred years will do the job.  But a few of these things for particular jobs (e.g. this city wants a lot of fresh water now) might be very useful.

Warm regards, Rick.

You could drop small bodies in the southern highlands while humans lived in the Northern lowlands.

You wouldn't want to hit Mars with big impacts but no reason you couldn't target carbonate or nitrate beds with smaller asteroids.

Edit: While I was researching another post, I came across this table in the Terraforming textbook.  I'm adding it to my post for your enjoyment.

Note: exponents are in brackets, e.g. 1.4(12) = 1.4x10^12.

Diameter of impactor  (km).... 1.............. 5............... 10.............. 100
____________________________________________________________
Impactor mass (kg).......... 1.4(12)....... 1.7(14)....... 1.4(15)...... 1.4(18)
Crater diameter (km)............ 16............. 66............. 122........... 931
Imported volatiles (kg)...... 6.8(10)....... 8.5(12)....... 6.8(15)..... 6.8(16)
Incr. in Pressure (Pa)......... 1.8(-3)......... 0.2............. 1.8........... 1770

Depth H2O depth (m)........ 4.7.(-7)...... 5.9(-5)........ 4.7(-4)......... 0.5
Devolatilized CO2 (kg)....... 4.0(12)...... 1.0(14)....... 4.1(140...... 4.1(16)
Pressure of above (Pa)........ 0.1............. 2.7............ 10.7.......... 1070

Depth equivalent of regolith meltwater (m)
.......................................... 8.1(-5)....... 0.01............ 0.08............. 81

Substantial Atmosphere Impact Erosion?
.......................................... No............... No........... Some..... Significant?

# of Impacters needed to produce 300 mbars of CO2
...................................... ~291,000..... ~112,000..... ~2,800......... <28

# of Impactors needed to produce 10 m of water globally
....................................... ~123,000........ ~980.......... ~120........... <1

The table includes bodies 50 km in size which I left out for room reasons.  There is another table that talks about comet impacts.  However these generally have such significant atmosphere erosion that they are not worthwhile larger than 10km in diameter.

Warm regards, Rick.

Why might we want to drop asteriods or comets on Mars?

1) Add mass to Mars & increase its gravity.  (This is so small an advantage as to be almost zero.)

2) Add volitiles to Mars.  Mars has been slowly losing water to space for billions of years.  From what I've read, a comet 1 km cubed in size would last tens of millions of years before its water was lost.  More Nitrogen, Argon and the like will help Mars perminantly.

3) Start volcanos.  This is a good thing bad thing.  Impacts large enough to start up volcanos will also blow away a fair bit of atmosphere.  By the time we start dropping giant comets on Mars the local population likely won't appreciate impact this large.

4) Land on Carbonates / Nitrates rock formations.  It is looking like Mars does not have much in the way of Carbonate rocks (too acidic?) but likely it has plenty of Nitrates caused by lighting reacting with nitrogen in the atmosphere.  If we drop a iceteroid with 5% NH3 on Mars on top of a nitrate bed we might get a nitrogen boost double what is in the comet itself.  (This is all speculative but likely in my view.)  If we don't have carbonate beds, we might be able to drop the comet on CO2 Clathrates and get a simular effect.  Basically by picking the impact points we can leverage the amount of mass in the comet.

5) Adjust the spin of the planet.  Again this result would be so small as to be almost zero unless we are talking about unreasonably huge numbers of rocks of very large sizes.

6) Adjust the albedo of Mars.  In another thread I calculated that if we darkened Mars with a carbonaceous chondrite asteroids to a depth of 1mm we would get a 5 degree C warming.  This might be enought to be significant for terraformers.

7) Melting the ice caps.  No question this would work but the problem is that water (or CO2) vaporized / melted will just refreeze.  Even the energy of fair sized asteriods would be dwarfed by the sunlight reflected by a 200 km^2 mirror hovering over the poles for a year or two.

Anyway those are the main reasons I see for dropping rocks.  If people would like to argue that we shouldn't drop rocks on Mars, perhaps we can move that question to a new thread?  In this thread the working assumption is that someone might want to do this and we will talk about how expensive it will be.

Warm regards, Rick.

Hi Jarek, everyone.
  I was hoping an ecologist would post a reply to your post but it doesn't look like that will happen so I will take a stab at it.

  If we want the Martian ecology to take advantage of all the energy and physical resources avalible to it, competition IS very efficient.

  We have not had much success with planned ecologies.  Biosphere 2 was the biggest attempt and its ecology was so simple that it crashed.  Many species overran the planned limits and humans had to become top level preditor, painstakingly squishing bugs for hours a day to try to keep things in ballance.

  Having said that in general, I have some specific comments to things you said...

  The sun is not never ending.  It is building up Helium ash in its core and is slowly burning hotter.  In around 800 million years we will have a run away green house effect and lose our oceans.  (See "The Life and Death of Planet Earth" by P. D. Ward & D. Brownlee for the details of how the Earth's ecology & geochemic cycles will react to the increasing insolation.)

  Even if we somehow set up a stable 'super efficient' ecosystem where there was little competition between lifeforms it won't last.  Mars is a high radiation environment and any genetic drift will select for organisms that compete more efficiently than the handicapped critters we want.

  Parasites are perhaps the ultimate in wasteful creatures but they are key in limiting populations that grow too dense allowing more variety in species.  And variety is the key concept needed for viable ecosystems.

  I think we would be better off selecting (and perhaps bioengineering) critters that are more tolerant of Martian conditions and let them create their own ecosystem. 

  Warm regards, Rick

Mars likely started off with an atmosphere of around 3 to 5 bar and it has taken billions of years to lose it.  (With much of the nitrogen being reacted by lightning into Nitrates).  It will likewise take millions of years to make a noticiable dent in Venus' new 3 bar atmosphere.  Very likely, the gasses from volcanoes will more than make up for any losses

Rick

Theoretically, you could change the rotation rate with a moon almost the size of Venus itself.  However, realisitcally, so much mass is not rotating very much that we are stuck with what we have got.

Rick

At this URL is 24 pictures of Vesta.

http://www.solarviews.com/raw/ast/vesta24.gif

I guess the question is how round is round?  To my eye, it is visibly not a sphere.

I am not saying anything at all as to what causes the magnetic field.  The solar wind is made up of charged particles.  They will be accelerated by the magnetic field.  (Which does work on them.)  The sun's own magnetic field is coupled to the solar wind.  It is far from clear to me what would happen to a small moon that is given an artificial magnetic field. 
Will the accelerations on it cancel out as it orbits Venus?  To answer that we need to know where the poles of the magnet are, if the moon is tide locked with the planet, etc.
However, since the magnetic field is accelerating particles even a super conductor will need more power to pump up the energy lost accelerating the solar wind.

You can not make a regular moon a permanent magnet.  They are not made of ferromagnetic materials.

It likely does.  I think that the very weak magnetic field is caused by a very slow rotation relative to the sun's magnetosphere which is passes thru and (thru induction) is coupled with.

I am confused by your question.  I think we may be talking about to different things. 

I'm talking about stabilizing Mars' climate by making a large moon (much more massive than Phobos and Demos).  Are you talking about changing the rotation rate?

The masses of the satellites are so tiny they almost certainly have no noticeable effect on Earth.

We could theoretically build a moon in any orbit that we wanted with any rotation that we wish.  We could put a moon into such an orbit that it would either spiral out or in.  The moon could either speed up or slow down Venus' rotation rate.  (Tho the kick would have to be pretty big to get it out of its tidal lock with the Earth.)

My understanding is that the Earth's magnetic axis does not go thru the center of the Earth either.

"The Solar System: Mars" by Linda T. Elkins - Tanton, published by Chelsea House Publishers, (c) 2006, 206 pages, hardcover.

I have mixed feelings about this book.  On one hand it has information on Mars that is not already in my library.  On the other hand it does not have enough 'oomph' to really make me happy.

This is a book that is intended to be a serious scientific primer for high school students on Mars.  It is part of a series of new books talking about the solar system and we have learned so much about Mars in the last few years it gets its own book.

As a primer to the planet it is excellent.  However it is not a fun read.  It is a long series of facts and essays.  Well organized, but lacking the excitment of the best written science books.

Also there is not much of interest to terraformers in this book.

If you are looking for an up to date book to give you the facts on Mars this will make a good choice.  I fully intend to read the other books in the series for the rest of the solar system.

However I am seriously wondering if there is enough new material to make it worth my while putting it into my library.

Warm regards, Rick.

Hi Rob, everyone.

Actually the dust storms are caused when the CO2 on the south pole sublimes.  If we raise the temperature 5 degrees then the CO2 will not form an ice cap and you won't get the wind to kick up the dust storms. 

However clouds and snow and ice will certainly reflect more heat back into space.  I've been playing around with inventing a Mars game (pun intended) and have been trying to figure out how to model this.

Warm regards, Rick.

Sure, if you can move an asteriod it is not that much more difficult to put it into an orbit.  The trick is to start with a distant orbit around Mars and then thrust for a few minutes at the furthest point of the elipse to circularize it and make it shrink.

Sure, but it is not that hard to get an orbit.

I don't have the numbers before me but I doubt that there are enough NMA to make a circular moon.  The moon has to get 800 to 900 km in diameter to squish into a sphere and that requires a LOT of asteriods.  However by heating them we can make it a lot easier for them to slump together.

Most space dust is not magnetic.

The solar wind would not rob a perminant magnet of its field.  An electro-magnet would do work on the solar wind and thus would require more energy to be constantly be fed into it.

No reason we couldn't lift all of Venus out of Venus' gravity field with enough energy.  Speaking practically tho, I can not see this happening even with a He3 economy.

As for shielding the magnetic field generators inside; you can't have it both ways.  If you want to have a magnetic field to do work on the solar wind, than the solar wind will do work on you.  If you shield your inner magnets with mu metal or superconductors, then the field won't reach outside your shield.

Huge impacts on Venus would almost certainly put crud into space that would find its way to Earth.  However most will take millions of years to get here, be small and be spread out widely over time.  So it wouldn't worry me too much.

I'm not sure what you mean by help angular momentum.  But a tiny amount of mass in orbit holds a giant amount of angular momentum.  For example, all the planets masses added together are less than 1/1000 the mass of the sun, but the planets hold more than 99% of the solar systems angular momentum.

Mars has no moon so its obliquity precess far more than the Earth's.  Even a relatively small amount of mass in an orbit will significantly stabilize the system.  So I think the answer to your question is a yes.

Luna is actually composed of mantle level rocks with high melting points.  The L1 point will always stay between the Earth and Luna as is a mathematical construct based on the mass of Luna and Earth itself.  Yes, people say that before the solar system ends, Luna will escape Earth orbit and enter orbit around the sun.  From there it could either hit the Earth, end up in orbit again or get kicked further away.

The angle of the magnetic field has to do with the flow of charged particles and interference with the solar magnisphere.  Also a planetary magnetic field is temporary.  Uranus' magnetic field has built up the way it is thru recent chance and physics not because of a late impact.  However late impacts are the accepted reason why it is tilted on its side.

If you are talking about a large body in the Venus - Sun L4 or L5 point it can't be that large.  L4 & 5 are only stable if the small body in those points are 5% or less of the mass of the planet.

Sure this would work.  You would need a huge amount of mass and Venus (for terraforming) would actually like to lose mass.  But speading up the Martian day (to even out more the temperature swings) while adding mass and heat to Mars would be very welcome.

99.9999% of the Plutonium on Earth is man made (with the exceptions of that natural breeder reactor in the Congo).  There is not enough made to put a dent on Mars' core.

Thanks for the interesting post StarDreamer.

Warm regards, Rick.

A small moon can hold a tremendous amount of angular momentum which is directly useful in stabalizing the degree that the planet tilts over many thousands of years.  It will stretch the crust and add heat to Mars thru tides.  It can be put into a decaying orbit (via rotation periods and mass concentrations) so after many million years it will hit Mars adding heat an mass to the planet and (perhaps) starting volcanoes and a MASSOUTFLO event.

All of these advantages can be had for many orders of magnitude less than trying to build up Mars' mass by a significant amount.

Nice question.

Warm regards, Rick