[Thunderbird]

Terraforming Mars


NASA has on occasion suggested that the human race could one day colonize Mars, and also initiate life to take hold on the surface. I understand that there have been nigh Sayers in the past about the limits of science, and I hate to be one, but I do not believe this at all feasible. It is a dead planet, and always will be, period.... What do you think ? Does NASA know something about Geophysics that I do not?

[freeztar]

Here are some older threads on the topic:

http://hypography.com/forums/space/8...ming-mars.html
http://hypography.com/forums/space/4...ming-mars.html
http://hypography.com/forums/space/5...ming-mars.html
http://hypography.com/forums/space/6...r-planets.html

[sanctus]

Wow, interesting read! I was already a meber of hypography the time they were posted but somehow I missed them...only sad that they always were quite short.

Anyway in the mean time there seem to be projects of manned flightts no?

[Thunderbird]

I have read though the past threads, and everything I can find on the net, but I still do not see how we can bring a dead planet to life.

The main problem, as far as I can see is one of a critical mass. The earth has a mass that allows for a solid core with a liquid outer core. This is due primarily to the resulting pressure gradients dividing layers into distinct divisions that move as independent units.

The earth is not just a rock with things growing on it, it is alive in a real sense, from the core though several layers outward, one layer dependent on the next. These complex dynamic interactions are fundamental for life, it seems only natural to deduce that these environment conditions reflects the life it produces, and sustains, and vice versa.

These dynamics allows for the formation of a mobile core, that envelops the planet in a protective electromagnetic shield, and not to mention the mobility of plate tectonics. Intuitively It strikes me that without these underling dynamics the planet could not sustain the dynamics of a life support system.

The taijitu represents an ancient Chinese understanding of how things work. The outer circle represents the entirety of perceivable phenomena, while the black and white shapes within the circle represent the interaction of two principles or aspects, called "yin" (black) and "yang" (white), which cause the phenomena to appear in their peculiar way. Each of them contains an element or seed of the other, and they cannot exist without each other.

[CraigD]

Originally Posted by Thunderbird

NASA has on occasion suggested that the human race could one day colonize Mars, and also initiate life to take hold on the surface. I understand that there have been nigh Sayers in the past about the limits of science, and I hate to be one, but I do not believe this at all feasible. It is a dead planet, and always will be, period.... What do you think ?

The notion of quickly turning Mars into a world where humans could comfortably live without special full-body-covering suits with breathing and temperature control features is, I think, pretty unrealistic.

The idea that we could muddle with Mars on a global scale in a way that makes it somewhat less expensive for human habitation strikes me as not infeasible.

However, such actions any time soon would be, IMHO, a great mistake, because it would terribly complicate the study of Mars, and thwart increasing our knowledge of the solar system, particularly how the inner planets including our own, formed and change over time.

In the far future (when “the far future” will be, I can’t guess), making Martian surface conditions similar to Earth’s might prove a great feat of “show off” engineering and entertaining novelty. Such speculation is, IMHO, properly the domain of SF.

The main reason for terraforming Mars is to gain human living space, which Mars has potentially a lot of - although much smaller than Earth (about 11% Earth’s mass), it’s all dry land, with about as much land area as Earth. The likely tremendous financial and material cost and uncertainty of such a project (or even just getting humans to Mars), and the abovementioned cost to science, and the feasibility of simply building artificial human-friendly worlds (O’neill cylinders, etc.) at lower cost and greater certainty, and affording lower-cost space travel, argues against terraforming Mar.

Originally Posted by Thunderbird

It is a dead planet, and always will be, period....

Though not as obviously alive as Earth, I think the question of life on Mars is far from settled.

Originally Posted by Thunderbird

Does NASA know something about Geophysics that I do not?

I would hope that NASA and its affiliates, packed as they are with the most apt and educated specialists on the subject, know a lot about Geophysics that you, I, and the collective membership of hypography, don’t know.

They also, I think, have a penchant for and a vested interest in producing scientifically plausible and esthetically pleasing popular edu-tainment on the subject of terraforming Mars, as well as the means and will to do good science considering its possibility. NASA is not only a science and engineering organization, but a education and self-promotion one. I trust it’s people are and will remain grounded enough in respect for basic science to avoid actually attempting such a program as a grand PR stunt, or some dubious get-rich scheme.

[Thunderbird]

Originally Posted by CraigD

I would hope that NASA and its affiliates, packed as they are with the most apt and educated specialists on the subject, know a lot about Geophysics that you, I, and the collective membership of hypography, don’t know.

They also, I think, have a penchant for and a vested interest in producing scientifically plausible and esthetically pleasing popular edu-tainment on the subject of terraforming Mars, as well as the means and will to do good science considering its possibility. NASA is not only a science and engineering organization, but a education and self-promotion one. I trust it’s people are and will remain grounded enough in respect for basic science to avoid actually attempting such a program as a grand PR stunt, or some dubious get-rich scheme.

NASA does need funding for Mars projects, and this is why you do not see studies realeased that say; Reasons why Teraforming Mars not fesiable, Its just not good PR.

[Thunderbird]

The only feaseble way is to add mass to the planet, the only way to do this is push Venus into Mars and start from scatch. Cooking time will be about 3 billion years.

[CraigD]

Originally Posted by Thunderbird

These dynamics allows for the formation of a mobile core, that envelops the planet in a protective electromagnetic shield, and not to mention the mobility of plate tectonics. Intuitively It strikes me that without these underling dynamics the planet could not sustain the dynamics of a life support system.

One might think that Earth’s magnetic field provides an important shield for its life, primarily against solar wind protons. Solar wind protons have about the same energy (1 keV), and have about the same effect of biological organisms - ionization, which can break chemical bonds in tissue, causing injury and death, or in genetic material, causing cancer and mutation – as soft x-rays.

One would, I’m pretty sure, be entirely wrong.

There’s a lot of evidence and reason to suggest that the absence of a magnetic field, while it might change the nature of life on Earth, causing different species to thrive, would not prevent it from having formed. A couple key ones come to mind

• The Earth’s ionosphere is also an effective charged particle shield, so even if it had no magnetic field, its wouldn’t get dramatically more radiation than it does.*
• Geomagnetic reversals. Geological evidence strongly suggest that the Earth’s magnetic field swaps polarity every million years of so (and sometimes much more frequently), with centuries or longer periods in which the field strength is nearly zero. Yet it appears these events did not cause mass extinctions, or otherwise much disrupt the ecosystem.
• Radiation extremophiles. Even if the preceding effects and evidence were absent, many organism, some surprising large and complex, have been discovered that thrive under sustained high doses of ionizing radiation. As the saying goes (well, OK, the saying appears to be from a 1993 Michael Crichton screenplay, but it’s a good one, IMHO, anyway ) “life, uh … finds a way.”

Models and probe data indicate that Mars no longer has a significant magnetic field, and a much thinner atmosphere than Earth (in large part, it’s believed, due to being stripped away by exposure to the solar wind), but it’s know to have an ionosphere, so its surface is effectively shielded from the particles that a magnetic field would also shield it from.

So it’s not so much that Martian life – if it exists – suffers from the lack of enough magnetic field, but from the lack of enough atmosphere. Models and probe data suggest that Mars once had a significant magnetic field and a thicker atmosphere, but lost both about 4 billion years ago. Whether Mars has ever had life, or still has some extremophile survivors, science has yet to compellingly reveal.
________________
* Calculating from data (Apollo 11 Solar Wind Composition Experiment and THE SOLAR X-RAY FLARE OF 7 JULY 1966,) on the observed solar wind and x-ray fluxes, we get then that the Earth’s magnetic field reduces its influx of a fairly narrow range of ionizing (1 keV, in the soft x-ray band) radiation by a large factor of about 100,000. The solar output is very variable, with infrequent burst of a few minutes of as much as 10,000 times the usual x-rays, so Earth without its magnetic field and atmosphere would be have about 10 times the x-ray band ionizing radiation as – bad news for the majority of surface-dwellers (though not as bad news as the lack of atmosphere :yikes: ).

Fortunately, Earth has an atmosphere, with an ionosphere that’s also an effective charged particle shield, so even if it had no magnetic field, its surface wouldn’t be awash in solar wind protons.

[CraigD]

Originally Posted by Thunderbird

The only feaseble way is to add mass to the planet, the only way to do this is push Venus into Mars and start from scatch. Cooking time will be about 3 billion years.

We’ve discussed the fun of planet moving and other super engineering before, in one of my favorite threads, “How to destroy the Earth”.
Working out the delta-v for a Venus-Mars transfer orbit gives 9485.4 m/s (5132.5 to start, plus 4352.9 to match orbits pre-collision, unless you’re keen on creating an Earth-mass debris belt in Earth-intesecting orbit ). Throwing in the mass of Venus gives an energy requirement of . Adopting the units of this post, that’s about 100,000 Great Pyramids worth of antimatter fuel, 4 days of the total energy output of the Sun, 250 billion years of the power consumption of our present day civilization, or 2/3rds the energy necessary to utterly destroy the Earth.

With that kind of energy, and the engineering needed to harness it, you could more easily surround Mars with heat lamps, manufacture an atmosphere from bits of gas giant planets, and while you’re at it, make some nice oceans, fuse that nasty Martian dust into some decent sand, and create a planet-size, 1/4th gravity beach resort (the volleyball alone might make it worth the effort )

This is realm of super technology (and science fiction), and showing off in the extreme, next to which O’neill cylinders and even interstellar colonization seem almost easy.

[modest]

I’m wondering if there’s an established way to determine the change in a planet’s surface temperature with increased atmospheric volume.

I’m thinking life can’t exist without liquid water. Adding an atmosphere to mars would help push toward the triple point on water’s phase diagram through the effect of pressure alone but not drastically and not close enough. Mostly what’s needed is a temperature increase.

I guess what I’m looking for is a source or method that gets how much atmosphere is needed to trap enough heat to elevate the surface temperature some 40 C.

We know the temp and pressure of Earth, Mars, and Venus. If we plotted a curve between them would we have at least a very approximate guess?

-modest