Yes. If it is possible to terraform Mars at all, this will take a thousand years according to the Mars society estimate - probably optimistic if anything - to get to the point where it's possible to grow trees there. Probably many thousands of years for a breathable atmosphere. And that is if everything works out. There is no hurry to start on a thousand year project. As a civilization we'd find it a major challenge to tackle a one hundred years project.
Can you imagine any present day government or organization committing to terraform Mars, commitment of billions of years every year, having to set up mines and factories on Mars mining a cubic kilometer of fluoride ore every decade and processing them to create potent greenhouse gases - and to build 245 nuclear power stations on Mars each generating half a gigawatt of power continuously just to power the conversion of the ore to greenhouse gases? That's the "easy way" to terraform Mars outlined by Chris Mckay in his 2004 paper.
Would any terrestrial government continue to pay the hundreds of billions of dollars every year surely needed to do that? Even for a century never mind commit to similar level of funding for a thousand years? You can't expect Mars colonists to build their own nuclear power stations etc from resources mined on Mars, they'd struggle to survive at all.
That's the easy way, thought to be easier than building thin film mirrors in orbit similar in area to a disk the diameter of Mars. Academically it is interesting, a clever solution, but dependent also on some assumptions about Mars that may not be valid. Practical though in terms of something we might feasibly do in the near future - I think - not really.
Indeed postponing it by a century may speed it up by many centuries, by finding a faster way to get it started which leads to it finishing sooner.
Think what all that finance and industry could do to help restore Earth and re-terraform the areas we have damaged.
But more than that, there is no guarantee at all that it would work. If you could make Mars into a duplicate of Earth, the oceans would freeze and trees couldn't grow there. That may well be what happened to Mars. To make it warm enough for Earth life, you'd need to warm it up - through greenhouse gases or planet scale mirrors. That's mega engineering, have to keep that up mining about a cubic kilometer of fluoride ore every decade to keep it warm, into the indefinite future.
A planet dependent on mega engineering like that could unterraform as quickly as it was terraformed. And remember Earth took hundreds of millions, or depending how you look at it, billions of years to terraform. A hundred thousand year terraform project would be a thousand fold or more speed increase on natural processes.
But there is also much that makes Mars different from Earth. These are just a few, go into more detail in my science blog posts.
And once we introduce life there, it is irreversible, much to go wrong if we introduce the wrong lifeforms.
Right now, Mars is of no use as a "backup". If anything happens to Earth, then Earth will still be by far the most habitable place in the entire solar system. So the best place to terraform will be Earth itself. Like it or not, Earth is the place we have to keep habitable and we can't escape to Mars. We'd take our problems with us anyway.
It is so easy and straightforward in some science fiction stories. But science fiction though great for opening our minds to new possibilities, is not science prediction or science future fact. Before the moon landing for instance, not one science fiction story got close to an accurate "prediction" of it. And many were set on a Moon with thick drifts of dust deep enough to swallow up entire vehicles without trace. Many other ways science fiction does not predict science fact accurately - from time to time it does but that's not its main function.
There is much also to go wrong.
If we want to experiment with living off planet, then large habitats such as city domes on the Moon, lunar caves, or probably easiest at least most controllable, Stanford Torus habitats would probably be the best place to start.
I can understand that many people are excited by the idea of terraforming Mars. It looks quite habitable in the photographs until you realise it has no atmosphere to breath even with an oxygen mask, is free of ice only because there is hardly any water (otherwise it would be solid ice from pole to equator with the warmest regions in the equator average temperatures same as Antarctica), etc etc.
Science fiction movies are works of imagination, science fiction stories also, and though often great for stimulating imagination and leading to new ideas, they are seldom super accurate predictions, except when set in the very near future and often "miss" even then.
See also: Robert Walker's answer to Is it ethical for humans to terraform other planets? Do humans have the right to completely change the nature of other planets or moons to suit our needs?
And my my science blog posts (all also available now as kindle booklets):
Can you imagine any present day government or organization committing to terraform Mars, commitment of billions of years every year, having to set up mines and factories on Mars mining a cubic kilometer of fluoride ore every decade and processing them to create potent greenhouse gases - and to build 245 nuclear power stations on Mars each generating half a gigawatt of power continuously just to power the conversion of the ore to greenhouse gases? That's the "easy way" to terraform Mars outlined by Chris Mckay in his 2004 paper.
Would any terrestrial government continue to pay the hundreds of billions of dollars every year surely needed to do that? Even for a century never mind commit to similar level of funding for a thousand years? You can't expect Mars colonists to build their own nuclear power stations etc from resources mined on Mars, they'd struggle to survive at all.
That's the easy way, thought to be easier than building thin film mirrors in orbit similar in area to a disk the diameter of Mars. Academically it is interesting, a clever solution, but dependent also on some assumptions about Mars that may not be valid. Practical though in terms of something we might feasibly do in the near future - I think - not really.
Indeed postponing it by a century may speed it up by many centuries, by finding a faster way to get it started which leads to it finishing sooner.
Think what all that finance and industry could do to help restore Earth and re-terraform the areas we have damaged.
But more than that, there is no guarantee at all that it would work. If you could make Mars into a duplicate of Earth, the oceans would freeze and trees couldn't grow there. That may well be what happened to Mars. To make it warm enough for Earth life, you'd need to warm it up - through greenhouse gases or planet scale mirrors. That's mega engineering, have to keep that up mining about a cubic kilometer of fluoride ore every decade to keep it warm, into the indefinite future.
A planet dependent on mega engineering like that could unterraform as quickly as it was terraformed. And remember Earth took hundreds of millions, or depending how you look at it, billions of years to terraform. A hundred thousand year terraform project would be a thousand fold or more speed increase on natural processes.
But there is also much that makes Mars different from Earth. These are just a few, go into more detail in my science blog posts.
- May have lost most of its volatiles already. Is not clear it has enough, may only have enough for perhaps a 2% of Earth CO2 atmosphere or so
- Less sunlight, only half, may not seem that much less but would be enough to put it into a permanent frozen state, no free water, no trees grow, with an Earth type atmosphere. That's why we would need to warm it up continuously into the foreseeable future through artificial means.
- Less gravity - this impacts on the biosphere as it means you need to produce three times as much oxygen for the same partial pressure in the atmosphere. So far nobody knows what effect it has on humans - either babies, foetuses or adults.
- No continental drift, so long term has no way to return limestone and other carbonates back to the atmosphere as CO2
- Needs a buffer gas such as nitrogen for humans to breathe, -where do you get it from
- No magnetic field - this means long term its atmosphere gets lost through solar storms - this is mainly for very long timescales though
- Close to asteroid belt. Ten times meteorite impact rate of Earth. Strange place to choose to run to if you are scared of large meteorite impacts hitting Earth as you'd get ten of those on Mars for every one on Earth for the same surface area. Also means a high rate of smaller meteorites and micrometeorites also - the atmosphere at present gives little protection.
- Right now surface is near vacuum, very inhospitable. Can't breath even with oxygen mask, need a full body pressurized spacesuit
- Cosmic radiation meaning you would need to limit time on the surface, lifetime maximum period of time you would want to spend doing EVAs or in surface rovers - if you follow the ISS type guidelines then in an entire lifetime you are permitted a total of 2 years on the surface or you greatly increase risk of cancer which you can get at early stages in your life.
And once we introduce life there, it is irreversible, much to go wrong if we introduce the wrong lifeforms.
Right now, Mars is of no use as a "backup". If anything happens to Earth, then Earth will still be by far the most habitable place in the entire solar system. So the best place to terraform will be Earth itself. Like it or not, Earth is the place we have to keep habitable and we can't escape to Mars. We'd take our problems with us anyway.
It is so easy and straightforward in some science fiction stories. But science fiction though great for opening our minds to new possibilities, is not science prediction or science future fact. Before the moon landing for instance, not one science fiction story got close to an accurate "prediction" of it. And many were set on a Moon with thick drifts of dust deep enough to swallow up entire vehicles without trace. Many other ways science fiction does not predict science fact accurately - from time to time it does but that's not its main function.
There is much also to go wrong.
If we want to experiment with living off planet, then large habitats such as city domes on the Moon, lunar caves, or probably easiest at least most controllable, Stanford Torus habitats would probably be the best place to start.
I can understand that many people are excited by the idea of terraforming Mars. It looks quite habitable in the photographs until you realise it has no atmosphere to breath even with an oxygen mask, is free of ice only because there is hardly any water (otherwise it would be solid ice from pole to equator with the warmest regions in the equator average temperatures same as Antarctica), etc etc.
Science fiction movies are works of imagination, science fiction stories also, and though often great for stimulating imagination and leading to new ideas, they are seldom super accurate predictions, except when set in the very near future and often "miss" even then.
See also: Robert Walker's answer to Is it ethical for humans to terraform other planets? Do humans have the right to completely change the nature of other planets or moons to suit our needs?
And my my science blog posts (all also available now as kindle booklets):
- Trouble With Terraforming Mars
- Imagined Colours Of Future Mars - What Happens If We Treat A Planet As A Giant Petri Dish?
- Why Nukes Can't Terraform Mars - Pack Less Punch Than A Comet Collision
- To Terraform Mars with Present Technology - Far into Realms of Magical Thinking - Opinion Piece
- Ten Reasons NOT To Live On Mars - Great Place To Explore
- Why We Can't "Backup Earth" On Mars, The Moon, Or Anywhere Else In Our Solar System
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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