Terraforming of Mars, how long it could take aside that we invent required technology

[Nikolai]

Why would you try to maintain a terraformed planet?

For the same reason we want our own planet to be amenable to human life. So that we have a place to live. And, more particularly, so that all of our eggs won't be in one metaphorical basket.

If it was sustainable on its own, its a good "lifeboat" in case something happens on/to Earth - but if Mars is doomed if humanity falters on Earth, what is the point?

That's the key "if". I think it would be foolish to try to terraform Mars with the goal of keeping it forever dependent on resources from Earth. The idea would be to make it an independent home for humanity eventually, with a population able to cope on its own with threats on a multi-century timescale and maintain its own planetary engineering.

All those resources would be better spent making Earth more like the paradise it should be, rather than turning an unihabitable place into a barely habitable place - or securing Humanities hold on space with asteroid colonies, colonies on titan, etc... which could include underground colonies on mars, sure, why not.

Why does these have to be mutually exclusive?

[Nikolai]

If you're suppose to constantly "terraform" Mars than it'd most likely be cheaper and better to build domed cities (easier to do on Mars due to lower gravity) than indefinitely pump resources into something that simply cannot achieve stable terraformation.

Cite? (ten chars)

[KerikBalm]

For the same reason we want our own planet to be amenable to human life. So that we have a place to live. And, more particularly, so that all of our eggs won't be in one metaphorical basket.

A place to live and not "having all of our eggs in one basket" that can be accomplished without terraforming - so the question still stands... why terraform?

That's the key "if". I think it would be foolish to try to terraform Mars with the goal of keeping it forever dependent on resources from Earth. The idea would be to make it an independent home for humanity eventually, with a population able to cope on its own with threats on a multi-century timescale and maintain its own planetary engineering.

Mars, as a terraformed world can never be independent of extra-martian resources. It is 1/10th the mass of Earth, its simply too small, to support a thick enough atmosphere for any significant length of time (in the geologic timescale). What is the point in making a home for billions of people, if it begins deteriorating as soon as its ready, and will be quite harsh again withing a couple millenia?

Why does these have to be mutually exclusive?

They don't, I'm simply speaking of prioritizing and making the most of resources.

Sending truly massive amounts of liquid/gaseous resources (hydrogen, nitrogen, water, methane, etc) to mars is going to waste truly massive amounts of liquid/gaseous resources. When making living space or refugia, there are much more efficient uses of resources

[Nikolai]

A place to live and not "having all of our eggs in one basket" that can be accomplished without terraforming - so the question still stands... why terraform?

You're right -- I didn't really answer the question.

Risk mitigation. It's much safer for humans to live in an area where the habitability can be measured in millennia rather than based on the moment-by-moment habitation maintenance capabilities of your domed city (or underground colony, or what-have-you).

Mars, as a terraformed world can never be independent of extra-martian resources. It is 1/10th the mass of Earth, its simply too small, to support a thick enough atmosphere for any significant length of time (in the geologic timescale). What is the point in making a home for billions of people, if it begins deteriorating as soon as its ready, and will be quite harsh again withing a couple millenia?

You misunderstand me. I don't mean to claim that it will be able to create an entirely closed ecosystem that humans would find comfortable. I mean that the Martians will be able to take care of things themselves. They'll be able to drop in resources every few centuries to take care of making sure that habitability doesn't go away after a few millennia.

They don't, I'm simply speaking of prioritizing and making the most of resources.

So am I. A smaller colony would still require resources to run; 100% reclamation is impossible. What do you have to demonstrate that a technologically robust colony -- one capable of continuing to allow the human race to grow, even if it has to act entirely on its own -- would require fewer resources per capita than terraforming with periodic maintenance?

Edited August 19, 2014 by Nikolai

[KerikBalm]

What do you have to demonstrate that a technologically robust colony -- one capable of continuing to allow the human race to grow, even if it has to act entirely on its own -- would require fewer resources per capita than terraforming with periodic maintenance?

Just a guesstimate based upon the amount of "unutilized" resources that are present in a biosphere.

The water per capita here on earth, for example, is much higher than the attemps at making closed ecosystems (which never quite worked when scaled up).

You don't just need to add enough water to irrigate sufficient crops as in some sort of closed underground hydroponics facility, but you need to basically saturate the environment with enough water to get standing pools of water + enough water vapor that you have condensation and rain and a functioning hydrological cycle.

You don't need to just heat a closed habitat to above freezing, but large swaths of the entire planet... etc.

It just seems inefficient to me, my guess is it would be very inefficient if the sole purpose is to create habitabe space for humans.

As to losses... the numbers on how many tons of various compounds Earth loses to space per time unit are staggering, and Earth's got a larger radius, more gravity, and magnetic field. Also significant recycling of the crust... Losses on mars would be so high that I think its unfair to require 100% reclamation of some closed habitat. A closed habitat with large stockpiles of resources would lose resources much slower than mars would lose resources if terraformed.

That said... I would like to see some planet terraformed (ideally one that doesn't have its own life already/is not suitable for life already).

I do place a lot of value on earth's biosphere, it would be great to have a functioning "copy" of it somewhere else - from the fish in the sea, the arhea and bacteria in the hot springs and ice, jungles, forests, plants that survive in arid conditions, ants, spider, snakes, etc...

but for that, we really need a copy of Earth. If you got mars up to 1 atm, you'd still have the basically unsolvable problem of low gravity, which would cause many many species to rapidly evolve into different forms.

Although that would still be pretty cool, I do have more fondness for Earth's current forms.

I won't deny the coolness factor... but... I think mars is just too small and old... if we could somehow move venus out to its orbit, smash them together (and then throw ceres on it for good measure + added water), then we might have something

[RuBisCO]

Atmospheric loses from Mars are over millions of years not thousands. So I see no difficulty in maintaining habitability of a Terraformed Mars.

[Jesrad]

What RuBisCo said.

Mars had a dense atmosphere for long enough to have liquid water erosion all over its surface. Bring it back to that state and you'll have millions if not billions of years worth of habitable planet estate.

Besides, Earth will become uninhabitable too, eventually. There is no such thing as "stable terraformation" ever.

Yet, even though I'm a lifetime member of Mars Society, I'd rather we start colonizing the lunar poles and asteroid belt.

[KerikBalm]

Atmospheric loses from Mars are over millions of years not thousands. So I see no difficulty in maintaining habitability of a Terraformed Mars.

I seem to remember reading the timescale being 10,000 years.... I'd ask you for a citation, but I'm having troublt finding one myself.

I'm assuming terraforming whereing you simply add the atmosphere, and the mantle is still solidified, and it still lacks a magnetic field.

The liquid H20 on mars lasted about a billion years it seems, which basically marks when the atmosphere became too thin (to retain heat, or prevent water from sublimating, water can't exist as a liquid on most of mars due to the low pressure).

During that time the atmosphere was protected by a magnetic field, and regenerated by volcanic outgassings.

Volcanic activity has ceased, and the magnetic field is gone.

http://science.nasa.gov/science-news/science-at-nasa/2008/21nov_plasmoids/

Plunking down a 1 atm atmosphere composed mostly of lighter O2 and N2 (rather than CO2) would create an atmosphere that wouldn't last nearly as long.

Unless you want to place some fusion reactors on mars that somehow pump massive amounts of energy into its core, melting the interior again and restarting a strong dynamo to give it a magnetic field.... but that it a huge task, much large than the more limited terraforming scenarios

[Pawelk198604]

I heard that some scientist question the morality terraforming, as it can destroy the native life forms like bacteria, which after all may exist even on Mars.

[KerikBalm]

http://www.nature.com/ngeo/journal/v7/n5/full/ngeo2137.html#f1

"Mars would have formed with ≥6–10 bars CO2 equivalent of carbon assuming the same initial [C] and [Kr] as Earth. 40Ar/36Ar and 129Xe/132Xe suggest that 90–99% of the initial atmosphere was lost before ~4.1 Ga (ref. 26). Subsequent loss rates are less clear; Mars’s C/84Kr ratio suggests P ~ 60 mbar following the Late Heavy Bombardment26."

60 millibar is about 10x what it is today, and would allow for water to be liquid (if the water is warm enough), but that is far too low for humans to breath, and the late heavy bombardment was over 3.8 billion years ago.... so lets say between 4.5 to 3.8 billion years ago, mars went from 6-10 thousand mbar, to 60, and today its just 6 mbar.

It lost atmosphere quite fast, and its in even worse shape today with the lack of volcanism, and the solar wind.

"Our technique rules out a thick, stable palaeoatmosphere and cannot exclude atmospheric collapse–reinflation cycles on timescales much shorter than the sedimentary basin-filling time. General circulation models predict that atmospheric collapse to form CO2 ice sheets and subsequent reinflation might be triggered by obliquity change5. If sediment accumulated at 1–100 μm yr−1 (ref. 20), our DTMs could integrate over ~106–108 years of sedimentation and contain many collapse–reinflation cycles. Therefore one interpretation is that smaller ancient craters formed while the atmosphere was collapsed, whereas rivers formed during high-obliquity, thick-atmosphere intervals."

Cycles of atmosphere collapse and return? interesting concept.

[Nikolai]

It lost atmosphere quite fast, and its in even worse shape today with the lack of volcanism, and the solar wind.

Solar wind is even worse than the LHB? Solar wind is even worse now than it was during the LHB?

How much of the atmosphere was lost to creation of mineral compounds, how much to solar wind, and how much to the LHB itself? In other words, in all this, do we have statistical models for determining the stability of a Martian atmosphere now (especially ones that would help us put atmospheric collapse/reinflation cycles into context)?

[TMS]

Google Dr. Robert Zubrin. Also, for more immediate results

My God, the first two minutes of that are painful!

[RuBisCO]

I seem to remember reading the timescale being 10,000 years.... I'd ask you for a citation, but I'm having troublt finding one myself.

I'm assuming terraforming whereing you simply add the atmosphere, and the mantle is still solidified, and it still lacks a magnetic field.

The liquid H20 on mars lasted about a billion years it seems, which basically marks when the atmosphere became too thin (to retain heat, or prevent water from sublimating, water can't exist as a liquid on most of mars due to the low pressure).

During that time the atmosphere was protected by a magnetic field, and regenerated by volcanic outgassings.

Volcanic activity has ceased, and the magnetic field is gone.

http://science.nasa.gov/science-news/science-at-nasa/2008/21nov_plasmoids/

Plunking down a 1 atm atmosphere composed mostly of lighter O2 and N2 (rather than CO2) would create an atmosphere that wouldn't last nearly as long.

Unless you want to place some fusion reactors on mars that somehow pump massive amounts of energy into its core, melting the interior again and restarting a strong dynamo to give it a magnetic field.... but that it a huge task, much large than the more limited terraforming scenarios

Well consider this study on terraform the moon, yep THE MOON: http://adsabs.harvard.edu/abs/2002iaf..confE.230R

If you want a magnetic field we could do it with an orbital ring.

I'm tired of people claiming that the gravity or lack of magnetic field makes terraforming mars impossible, show me the calculations, what is the rate of lose? Calculate out how many mbars would be lost per year, show me that calculation, then I'll believe you.

As for mars atmospheric losses 4 billion years ago: IMPACTS, impacts can account for most of atmosphere loss, not solar winds.

http://www.nature.com/nature/journal/v338/n6215/abs/338487a0.html

http://onlinelibrary.wiley.com/doi/10.1029/98JE02074/pdf

"Based on tabulated crater densities, the process of atmospheric cratering can account for a loss of 50–90% of the Martian atmosphere since the onset of the geologic record. Stable isotope fractionation measurements suggest that loss of ∼90% of atmospheric species to space has occurred via solar wind pick-up-ion sputtering [Jakosky and Jones, 1997]. Combined, ∼95–99% of Mars' atmosphere could have been lost to space."

So that means the impactors took out 50-90% of the atmosphere and since then solar wind as taken out 90% of what remained. That a solar wind loss rate of less then 1 mbar per 1 million years.

Edited August 22, 2014 by RuBisCO

[Jesrad]

Also take into account that much of the CO2 solidified on the poles.

[RuBisCO]

Also take into account that much of the CO2 solidified on the poles.

Yes that was taken into account but sequestration models only account for tiny fraction of the loss.