rejuvenating mars

[moreandless]

among the fun discoveries by MGS , Mars Express and Odyssey is the certainty that Mars is concealed
under a blanket of dust. There appear to be glaciers buried by dust and not necessarily very deeply
eg...Phoenix lander . I would love to see Zubrin's mars-direct fuel manufacturing technology at work
(scale model lets say)for a year followed by a liftoff utilizing the finished product. I believe the lost
Polar lander intended to send penetrating missiles into the subsurface. A similar device could perhaps
clear the dust from an area for our fuel factory.

 

[MeteorWayne]

I would say that calling what was below Phoenix a glacier, is a substantial stretch of the known facts.

Yes, there was an ice layer. To call it a glacier (implying unlimited water/ice) is not supported by the facts.

 

[moreandless]

there are numerous sources of information about dust covered glaciers on Mars
including statements such as "not just those known to be under the Phoenix lander".
One,at about 60deg latitude is 3 times larger than the city of Los Angeles and a half mile thick.

after making that post i was looking at other interesting threads and came across a report
out of the Lunar and Planetary Conference 2010 which discusses this very same subject

 

[Couerl]

When we reduce Venus' atmosphere to acceptable levels we can construct giant girders on it's equator and place some self-deploying solar sails that open automatically on the side that is turning away from the Sun and close on the other. That way we can spin up the Venus to decrease the length of the day.

[/sarcasm]

I think it might be simpler just to have everyone on the surface run really fast in the same direction to speed it up. :lol:

 

[moreandless]

i tend to favor the new "flexible" path owing to the fact that there are many important
robotic missions that need to be conducted so that when we are ready with our new
propulsion systems the ' ground truth' will be better understood. For instance it is
essential to know if we can manufacture not only fuel but greenhouse gasses on mars.
msfc

 

[Fallingstar1971]

OK lets "jump start" Mars' magnetic field.........

Earth does it by having a molten spinning core. Tidal flexing from the moon may just help keep it that way.........

So........

What if we moved the entire asteroid belt into orbit around Mars? Would that be enough mass to be "moonlike" and perhaps re-introduce tidal flexing, which could re-introduce a moving core, which could jumpstart the magnetic field.

Of course, getting equipment out to the belt will be difficult, but some small, steerable rockets and some physics pros could get it done.

Who knows, perhaps Mars could condense the asteroids into a moon with its gravity.

Once the field is active, all of the topics other suggestions and ideas can be realized.

The same idea could be applied to Venus to speed up its rotation, but I have to wonder what made it so slow to begin with. It very well could have been knocked upside down by an early impact, and if thats the case, then I dont know if a moon would help at all. (Not to mention the danger of whizzing asteroids across Earths orbit)

http://dawn.ucla.edu/personnel/russell/ ... venus_mag/

It appears that Venus' magnetic field is shot as well. So no matter which way you go, this problem will either need to be addressed or your facing a cost that will run continuously throughout the life of the colony. (Unless you can cure cancer. That alone would greatly increase our range by making us immune or at least practically treatable to certain radiations)

Also, no matter how you do it, its going to take time. ALOT of time. Governments, like people, want instant results, otherwise project funding gets re-directed due to our governments short attention span. Like I said in a previous post, its getting to the point where "If it cant be done in 4 years or less, dont bother because your funding will be cut by the next guy to come along"

Star

 

[moreandless]

Exciting Mars' core is a must . Which is why i lean toward some brutal methods like
asteroid bombardments and nuclear core-seeking devices. I think there is a lot of merit
to the notion that uranium and other actinides are powering our own magnetic field.

 

[Couerl]

Exciting Mars' core is a must . Which is why i lean toward some brutal methods like
asteroid bombardments and nuclear core-seeking devices. I think there is a lot of merit
to the notion that uranium and other actinides are powering our own magnetic field.

Then all we'll have to do is hang around a half billion years for it to cool back down and take effect. :ugeek:

 

[B_Cary]

To get a lot of CO2 into Mars' atmosphere quickly, we could recycle a few nukes. The trick (aside from getting them there ) would be to have them impact the south (bigger) polar cap. Massive sublimation of CO2 and vaporization of water would result.

'At Hiroshima [12.5-15 Kt], it has been estimated, as Glasstone* states, that: "solid materials on the ground immediately below the burst probably attained surface temperatures of 3,000 to 4,000°C (5,400 to 7,200°F)." And as far away as 0.61 mile, they may have reached 1,800°C (3,270°F). With a 250 Kt weapon such heat could readily extend from 1.1 to 2.6 miles; [...]'

1,800°C is a lot of carbon dioxide sublimating. Conversely, the distance before the heat subsided to, say, 100°C would be enormous. Does anyone have an idea of how much CO2 would be released by a 250 Kt explosion?

*Samuel Glasstone and Philip J. Dolan, The Effects of Nuclear Weapons, published by the United States Department of Defense and the United States Department of Energy. Used at http://www.nukefix.org/weapon.html.

 

[GraemeH]

But I disagree that Venus would be 'easier' than Mars to teraform due to reasons stated in Menelloms post. The only thing that is harder on Mars is maintaining an atmosphere long term due to not much of a Mars magnetic shielding to protect against solar wind blowing it off. But that can be done with large factories continuously pumping gases into the atmosphere.

I'd be interested in hearing some of the data on how quickly Mars would lose its atmosphere if terraforming attempts were made. There's long term and there's long term. If Mars might lose whatever atmosphere we help generate within a couple decades, it's a big for terraforming problem. On the other hand if it'd lose it over the course of a few centuries well... presumably we'll have come up with a solution long before it would become a problem.

Hmmm, erosion of an atmosphere by the solar wind is a very small contribution. Solar wind and radiation work by dissociating atmospheric gas molecules, for example;

2H20 ------> 2H2 + O2

Hydrogen is then easily lost because of it's low mass and thus it's high Vrms (see below) exceeding the escape velocity of the planet.

Mars current atmospheric solar erosion rate is calculated as 6g per sec - avergaing over all species ( http://www.sciencemag.org/cgi/content/a ... 5/5811/501 ).

The main contributor to non equilibrium atmospheric loss is the velocity of individual gas molecules exceeding the escape velocity. In effect, the young warm wet Mars lost atmosphere and/or froze out, cooling until an equilibrium was reached. The issue with any Mars terraforming proposal is that without increasing the escape velocity (higher Martian mass/gravity) as soon as you switch on your atmospheric processing units and increasing the temperature, Mars will try to attain equilibrium by losing atmosphere.

To give an analogy, it would be like trying to blow up a balloon which has got a leak. The bigger you try to blow up the balloon, the larger the leak becomes!

Here is an outline of how you could go about calculating a very rough approximation:

- Calculate the root mean squared gas velocity from Vrms = SQRT ((3 x R x T)/M)
where;
R is the ideal gas constant 8.314 J per mol per K
T is the temperature in Kelvin (Mars has an average surface temp of 227 K)
M is the molar mass of the ideal gas in kg (CO2 = 44E-03)
- Assume a Gaussian distribution of gas velocities centered on the above Vrms, with a distribution width (say) of 3 sigma.
- The proportion of atmospheric loss is the distribution above the Martian escape velocity (5.03 km per sec).

Uuuuuugh, Venus has issues too. :roll: Not only would you need a big sunshade, but you would have to deliver a huge amount of water into the atmosphere to lock up all that CO2 into carbonate rocks, otherwise the atmosphere would just cool and get even denser than the 90 bar current condition. I suspect that even if you could accomplish that, the terraformed Venusian climate would be highly unstable without plate techtonics and the recycling of CO2.

To be honest, IMHO, our Earth currency would be far better spent creating a sub-regiolith habitat on the moon....but that's a whole different thread!

 

[eburacum45]

In effect, the young warm wet Mars lost atmosphere and/or froze out, cooling until an equilibrium was reached.

But it seems to have taken a long time for that equilibrium to be reached. Mars may have had a considerable atmosphere for more than a billion years.

Uuuuuugh, Venus has issues too. Not only would you need a big sunshade, but you would have to deliver a huge amount of water into the atmosphere to lock up all that CO2 into carbonate rocks, otherwise the atmosphere would just cool and get even denser than the 90 bar current condition.

Note that adding water also adds extra oxygen to the planet.which would also need to be combined with the crust. Relying on geochemical processes to get rid of the excess carbon dioxide and oxygen would takes a long time.

 

[Couerl]

Uuuuuugh, Venus has issues too. :roll: Not only would you need a big sunshade, but you would have to deliver a huge amount of water into the atmosphere to lock up all that CO2 into carbonate rocks, otherwise the atmosphere would just cool and get even denser than the 90 bar current condition. I suspect that even if you could accomplish that, the terraformed Venusian climate would be highly unstable without plate techtonics and the recycling of CO2.

People were surprised to discover a great deal of water on the moon and the moon is very small compared to Venus, my guess is that there's a great deal of water on Venus as well, beneath the surface and trapped in the rock itself and the fact that plate tectonics is inactive may actually have helped to preserve it en situ. Virtually all rock has some water content and Venus is packed full of So2 in the upper atmosphere, which loves to break down rock.. Rain the So2 out by shading the planet and the rocks will erode and out will come the water. This is very similar to how it happened on Earth. No need to deliver anything except for the giant, (fictitious) tin-foil umbrella.. It's still a silly pipe dream because in either case we're talking about many millions of years of natural geologic processes before it is ready, but it's far less silly than "terraforming" Mars. We couldn't even begin to terraform the Sahara and that was a lush and wet and warm place a mere 10 thousand years ago. There's silly to the 10th power and then silly to the 100th power and if we could actually do either, then we would simply do both. :lol:

 

[neilsox]

Earth has 0.4 millibars of carbon dioxide at sea level. Has any one grown plants at 1000 times that much carbon dioxide = 400 millibars? Too much carbon dioxide may be bad for plants, just as too much oxygen is bad for humans. My guess is 400 millibars of carbon dioxide will only warm Mars 18 degrees f = 10 degrees c, so Mars will still be too cold for robust agriculture except at the lowest elevations near the equator. If so, we need other green house gases plus lots of extra solar energy from statite mirrors about 200,000 kilometers from Mars, to provide oxygen by plant photosynthesis.
If Mars presently looses 6 grams of atmosphere per second that may jump to 600 grams per second, with Mars 20 degrees c warmer with 20 millibars each of oxygen and nitrogen and 50% relative humidity at the top of the atmosphere. I'm counting the water vapor as part of the atmosphere.
600 grams per second should be much easier to replace than maintaining the giant statite mirrors very long term. Getting the atmosphere to almost 1/2 bar is however extremely costly except with very optimistic results. Neil

 

[eburacum45]

People were surprised to discover a great deal of water on the moon and the moon is very small compared to Venus, my guess is that there's a great deal of water on Venus as well, beneath the surface and trapped in the rock itself and the fact that plate tectonics is inactive may actually have helped to preserve it en situ. Virtually all rock has some water content and Venus is packed full of So2 in the upper atmosphere, which loves to break down rock.. Rain the So2 out by shading the planet and the rocks will erode and out will come the water. This is very similar to how it happened on Earth. No need to deliver anything except for the giant, (fictitious) tin-foil umbrella.. It's still a silly pipe dream because in either case we're talking about many millions of years of natural geologic processes before it is ready, but it's far less silly than "terraforming" Mars. We couldn't even begin to terraform the Sahara and that was a lush and wet and warm place a mere 10 thousand years ago. There's silly to the 10th power and then silly to the 100th power and if we could actually do either, then we would simply do both. :lol:

It's hydrogen which is in short supply on Venus; this gas is almost certainly not present in the crust except in trace amounts. Probably there is enough to cover the whole surface of Venus with a metre of water. Perhaps that is enough for some sort of colonisation, but it seems unlikely.
Incidentally I'm quite sure that long before we try anything like terraforming Mars or Venus we will have terraformed the Sahara, unless someone wants to preserve the desert habitat.

 

[crazyeddie]

Well that checks off one of the concerns as far as atmosphere is concerned. The bigger problem looks like it would be radiation. The daily dose of radiation that a hypothetical 'Martian' would experience would be high, and while it could me managed, it'd still wreck havoc. Large blasts of solar radiation like from a flare would especially do a LOT of damage.

Radiation, more than atmosphere or temperature is the biggest hurdle for terraforming Mars. Settlements would need to be contained or possibly even subterranean, for a long time if not permanently. Short of finding a way to "reboot" Mars' planetary dynamo or else artificially producing a planet sized field (either of which is a century or centuries beyond our current capability) there's nothing that can really be done about the radiation problem on Mars.

I've read that an atmosphere of at least 390 millibars would be sufficient to protect people living on the surface of Mars from ordinary solar and cosmic radiation. Only during solar storms would people have to seek underground or shielded shelter.

 

[neilsox]

Earth's magnetic field decreases radiation exposure for for most of the planet, but not for the North and South Magnetic poles. The people who live near the North magnetic pole have a low incident of cancer, for several reasons. The possible implication is solar radiation as a cause of cancer is over rated, so Mars settlers may do fine in spite of the lack of magnetic field. If the settlers need the equivelent of SUBA gear, most of them will be outside rarely, and radiation inside their shelters can be lower than typical Earth structures. Possibly large super conducting coils can further reduce local radiation exposure. USA citizens are outside less than two hour per day, on the average, so this won't be a lifestyle change for many of us. Vehicles can provide protection from the secondary radiation which typically passes though the thin atmosphere of Mars. Neil