Terraforming Mars

[GIThruster]

Growing food on Mars: https://www.thalesgroup.com/en/worldwid ... -you-space

[Diogenes]

I still haven't seen anyone suggesting anything about what we should try to do with Phobos.


Boost it up or crash it into the planet?

[GIThruster]

The energy you get from crashing Phobos into Mars to change its orbit, you have to put into Phobos to crash it into Mars, so no real gains here.

Now if you smack Mars with a comet made of CO2, that's a whole new ballgame.

[choff]

If Ceres turns out to be an ice ball maybe we could smash that into Mars!

[williatw]

I thought this was more or less settled a few years back; the most effective way to heat up Mars with minimal side effects:

viewtopic.php?f=8&t=3466&hilit=super+gr ... e&start=45

This might interest you: http://www.ens-newswire.com/ens/oct2008 ... -24-01.asp Quoting: A gas used in manufacture of flat panel televisions, computer displays, microcircuits, and thin-film solar panels is 17,000 times more potent a greenhouse gas than carbon dioxide, and it is far more prevalent in the atmosphere than previously estimated. The powerful greenhouse gas nitrogen trifluoride, NF3, is at least four times more widespread than scientists had believed, according to new research by a team at Scripps Institution of Oceanography at the University of California, San Diego.
17000X times CO2 at trapping solar heat means a relatively small amount of it manufactured on Mars and outgassed into the atmosphere would warm up the planet enough to cause the massive amounts CO2 and water at the poles and permafrost to start outgassing. It would cause a runaway greenhouse effect on Mars. I am essentially letting the sun do the heavy lifting as far as warming up the planet.

New measurement techniques have revealed much higher atmospheric concentrations of NF3 than expected, which can be partially attributed to the fact that industrial losses of the gas had been underestimated. NF3 emissions are increasing rapidly – rates of industrial production increased 40-fold between 1992 and 2007 alone . This is particularly alarming because NF3 has a 100-year global warming potential of 17,200, meaning that it is 17,200 times more powerful than carbon dioxide in trapping atmospheric heat over a 100-year time span – much higher than most other GHGs.

http://www.wri.org/blog/2013/05/nitroge ... nventories

[hanelyp]

Greenhouse gas theory of global warming is rubbish. Total surface pressure has much more impact on surface temperatures than what is in the atmosphere, by way of adiabatic compression. Convection cancels most of the "greenhouse gas" effect.

[williatw]

Greenhouse gas theory of global warming is rubbish. Total surface pressure has much more impact on surface temperatures than what is in the atmosphere, by way of adiabatic compression. Convection cancels most of the "greenhouse gas" effect.

I was talking about using NF3 to start a runaway greenhouse effect on Mars where it would do some good. The fact that NF3 is 17K times more powerful than CO2 just seems to confirm that CO2 is just a weak greenhouse gas. Of course on Mars CO2 is the bulk of the atmosphere with many times more mass frozen on its surface waiting to be outgassed; the pressure on Mars after the CO2 outgassed I believe is estimated to be about 300 mmHg. Enough so that temperatures would be comparable to Earth with atmospheric pressures high enough for liquid water to exist on the Martian surface

[Diogenes]

The energy you get from crashing Phobos into Mars to change its orbit, you have to put into Phobos to crash it into Mars, so no real gains here.

I dunno, not having an orbital time bomb seems like a pretty good gain to me.

Now if you smack Mars with a comet made of CO2, that's a whole new ballgame.

Mars needs more mass, and if we are serious about settling on it we need to figure out ways to add some. Especially C02 and water.


If Mach effect works, and if we get polywell (or equivalent) working, we can make some unmanned space tugs to move ice bergs out of Saturn's rings.

[GIThruster]

If Mach effect works, and if we get polywell (or equivalent) working, we can make some unmanned space tugs to move ice bergs out of Saturn's rings.

If M-E works, we can open a wormhole in Venus' atmosphere and simply let the CO2 rush through and replenish Mars. It will then hold heat quite well and we'll even be able to plant it. A few years of plants converting CO2 to O2 and we'll even be able to breathe there.

If what you want is to change Mars' orbit, you don't want to hit it with part of it's own orbital mass, which includes all its satellites. You want to redirect something from outside like a comet, and they usually have an abundance of CO2.

Not sure I'd want to be on Mars when it is hit by a comet. Yeah, some added atmo and a warmer orbit would be nice, but I'd guess the tectonic stresses would generate Marsquakes (well what should we call them?) for decades.

[hanelyp]

Material can be made to flow "uphill" through a wormhole between Venus and Mars? Sounds like a violation of energy conservation. Yes, Venus has high surface pressure, I don't think that high.

[krenshala]

Its downhill from the Venus surface pressure of 9.2 megapascals to the Mars surface pressure of ~600 pascals.

[GIThruster]

Material can be made to flow "uphill" through a wormhole between Venus and Mars? Sounds like a violation of energy conservation. Yes, Venus has high surface pressure, I don't think that high.

I'm not very familiar with the physics. Why would you consider it "uphill"? At the altitude on Venus where pressures and temperatures of CO2 are Earth-like, it would seem to me atmo would naturally flow through a wormhole. On Mars there's near vacuum, and one could place the mouth significantly above the planet surface if more vacuum is needed. So why would you have an "uphill" flow? Seems very downhill to me.

[Diogenes]

Material can be made to flow "uphill" through a wormhole between Venus and Mars? Sounds like a violation of energy conservation. Yes, Venus has high surface pressure, I don't think that high.

I'm not very familiar with the physics. Why would you consider it "uphill"? At the altitude on Venus where pressures and temperatures of CO2 are Earth-like, it would seem to me atmo would naturally flow through a wormhole. On Mars there's near vacuum, and one could place the mouth significantly above the planet surface if more vacuum is needed. So why would you have an "uphill" flow? Seems very downhill to me.

Gravitational gradient. Whatever energy it takes to move a mass from Venus to Mars, is the same energy it would take to move an equal mass of air to Mars.


The atmospheric pressure on each planet has nothing to do with it.

It's the gravity gradient pressure between Mars and Venus that has to be overcome.

[GIThruster]

It doesn't take any energy to move mass through a wormhole. The mouth of the wormhole alters the gravitational gradient at whatever point it is created, such that it goes negative, so speaking of the gradient at whatever point is was before the wormhole is not the proper way to view the problem.

The wormhole is like a hill, but it is a downhill at both ends, since it is the mouth that needs to be held open by negative mass with negative inertia. The qualification for what makes an "absurdly benign" wormhole, is that the gradient at the mouth is not too steep for a human to survive transit through it. However, gas pressures at terrestrial levels, easily overcome things like gravity gradients. Try to remember that gas moves at a significant fraction of c at room temperature. See Brownian Motion for numbers here.

Point is though, that it is a downhill climb into the wormhole at both ends, and one supposes flat between. It's like walking through a valley. Pressure matters much more here than the gradient. Ask yourself if you puncture a balloon at the mouth of the wormhole, would the gas inside still want to flow out of the balloon? Sure it would!

But that first sentence, surely that can't be true? "It doesn't take any energy to move mass through a wormhole." Well does it take energy to move mass through a siphon? No. It can certainly take energy to climb to the p;pint of one mouth, to enter it, and could require more energy to enter than to leave, but that concerns where the mouth is located, and what is the gradient in the terrain surrounding the mouth opening not what passes through it.

[krenshala]

The suns gravity on Venus is 5.983 x10^33 kg m^2/s^2, while the on Mrs it is 7.887 x10^32 kg m^2/s^2. Thats a difference of 5.1943 x10^33 in Venus' favor. I guess the question then becomes is the fact that Venus' atmosphere is 15333 1/3 times greater sufficient to overcome the gravity difference.