Talk-Polywell.org

Heading on a tangent to a thread on news...

One issue with terraforming Mars is the planet's lack of a magnetic field. A (superconducting?) current loop around the equator comes to mind as a very effective, if difficult, option.

Personally I think any real solution needs to be a practical one, and building a superconductor all the way around a planet doesn't seem practical to me at all. Why produce magnetic field in places where you don't need it, such as behind the planet? If you can build in constant thrust station keeping so you don't need an orbit, you can put it very close to the Earth and perhaps even tap into the radiation as your power source to stay on station. This way you're building the smallest shield possible. A ring a few hundred km above Mars that is a few hundred km diameter might generate sufficient field to protect across the 7,000 kilometers diameter of Mars. Seems a lot cheaper than building a 7,000 km dia. ring on the planet.

Two much smaller magnets, one at each pole.

Well the magnetic field is mostly needed to protect against radiation.
Stripping a planet of its atmosphere takes billions of years, so we would not need it to keep the atmosphere.

For radiation shielding you can use a narrow depth of a higher intensity magnetic field, or a large depth of a weaker field. How intense would the field need to be for localized shielding?

I don't see a shield at great distance from Mars towards the sun doing much.

Terraforming Mars is Zubrin's schtick. He thinks that warming the planet by 4C or so will cause all of the CO2 to out-gas from the ice caps and regolith and that this will produce an atmosphere of, say, 130 torr over a 50 year period. This, in turn, will warm the planet to where is is something like Northern Canada. Its certainly not an Earth-like environment, but 130 torr atmosphere would allow one to walk outside with only breathing gear rather than a bulky pressure suit. It would also allow for very large domes to be built, since there would be little pressure differential. This partial terraforming would be a major improvement over the existing Mars (and would actually make it similar to what Mars was thought to be like prior to Mariner 4).

I have no idea if this is possible or not. However, to make Mars with a breathable atmosphere would be nearly impossible.

KitemanSA wrote:Two much smaller magnets, one at each pole.

This is the exact idea I discussed with a friend several years ago. Might even help if booster magnets are added elsewhere on the planet's surface.

I think the first thing that needs to happen though, is to add more mass in the form of more water. Drops some iceteroids on it.

kurt9 wrote:Terraforming Mars is Zubrin's schtick. He thinks that warming the planet by 4C or so will cause all of the CO2 to out-gas from the ice caps and regolith and that this will produce an atmosphere of, say, 130 torr over a 50 year period. This, in turn, will warm the planet to where is is something like Northern Canada. Its certainly not an Earth-like environment, but 130 torr atmosphere would allow one to walk outside with only breathing gear rather than a bulky pressure suit. It would also allow for very large domes to be built, since there would be little pressure differential. This partial terraforming would be a major improvement over the existing Mars (and would actually make it similar to what Mars was thought to be like prior to Mariner 4).

I have no idea if this is possible or not. However, to make Mars with a breathable atmosphere would be nearly impossible.

Currently perhaps, but with effective space tugs, it might be doable. Keep adding Iceteroids to the planet, and see if something can be done about pushing Phobos and Deimos together and getting them to orbit right.

And how could this article be more timely?


http://www.popularmechanics.com/how-to/ ... =pm_latest

Yeah, I was considering this as well. Do some sort of cosmic pool billard and dodge asteroids into each other until a very big one (with a nice water content) gets just the right nudge to come crashing into Mars. That would pretty much achieve everything at once. But once I learned about the theory with the super greenhouse gasses, I revised my earlier opinion. I think that the nuclear factories/greenhouse gass idea would be faster and cheaper to do. It could also be more controlled.