Cosmic radiation is only about 9 rem/year on a fully exposed Mars surface, mostly so low because the planet provides a rater large amount of shielding. A simple sandbag roof over living quarters can reduce that by a third down to 6. Since the vast majority of time settles aren't in the open, it is reasonable to conclude the risk of cosmic radiation, which accounts for ~ half our terrestrial annual exposure, isn't all that high. It would be space crews who would be expected to see the risk since they have no planetary shield. Transatlantic airline pilots get around a rem per year. The Earth only shields us roughly half of cosmic radiation - which is due mostly to the planet acting as shield rather than the magnetosphere.

Solar flares are likewise of little concern to a Mars surface dweller. The planet and atmosphere block out most of their radiation. Relatively simple sandbag roofing under a dome can reduce it even further, to the extent that under a small sandbag level roof a settler would only experience about 3 rem during a flare. Fortunately we know in advance and have warning time to get into even more secured areas for the minor duration of a flare. So we have no need of electromagnetic shields, err fields, to provide the protection needed.

Now as to fusion development, what we know currently points to deuterium being a key ingredient. Mars' concentration of which is roughly six times the level of seawater on Earth. So once we figure it out, we don't need to go looking elsewhere for the fuel. Which ties us back into the original topic. ;) Deuterium last I knew was already running at over $10k per kilo (or was it pound? IDR). I can only image what would happened to the price if demand for it suddenly shot up. And with mars having a "high' concentration of it, it wild be come a very hot commodity indeed.

Yeah the teleporter was a tad tongue-in-cheek. A lander would be needed, but that lander has to come back out of the gravity well. At that point we're back to the cost/problem of getting off of the Earth's surface.

It could be based off of a Martian hopper - a VTOL "hopping" coat which uses rockets to go up, "slide over" and go back down. Quite handy for local travel and feasible because of the plentifulness of fuel supply and lower gravity.

This is just a part of the larger, international effort to attain fusion. The largest tokomak today is the International Thermonuclear Experimental Reactor (ITER), being built in France. The international collaboration is comprised of the United States, Japan, Russia, China, South Korea, India, and the European Union. Check out http://iter.org for more information. My PhD is in nuclear engineering, with graduate coursework in plasma physics and fusion reactor engineering. According to the ITER website, they plan on "First Plasma" by December 2025, which, when you think about it, is not really that far off anymore (8 years). With all the partners, it took them what seemed like forever (10 years) to just settle on site selection, but France eventually got it. ITER is much larger than any previous tokomak, with a "gain factor" of 10. That means the fusion energy produced within the plasma is ten times the power required to keep the machine running. Previous large machines were closer to 1. The next step is what they are calling "DEMO" - an as yet unnamed successor to ITER that will demonstrate net electricity generation by adding energy removal equipment to the tokamak. ITER will not generate electricity because the energy removal systems would interfere with all the engineering diagnostics (ITER will be very heavily instrumented to iron out all the final plasma physics details). "DEMO" will essentially be about the same size as ITER, but without all the diagnostics, and with energy removal systems. After DEMO, the world would be ready for building commercial fusion energy plants. Using heavy isotopes of hydrogen (deuterium, found in all water), the energy reserves are practically unlimited. By natural occurrence, deuterium is 0.0115% of all hydrogen, but there is a LOT of water in the world's oceans! It's actually a bit more complicated than that, because "first-generation" tokomaks will burn deuterium-tritium (D-T) plasma, as that reaction takes place under easier-to-obtain conditions. D-D reactions need hotter, denser plasmas. But, tritium can be "bred" from lithium, and the world's lithium reserves are very large. Eventually, fusion reactors should be able to burn D-D, but that will require more advanced designs. Fusion energy could power the global economy for millions of years.

He developed a "warp field" around the ship, that's how he broke the light speed barrier.

Of course, now we're way off the original topic. Not that I mind, with this threaded organization of comments.

What the producers would need to develop is not a teleporter. I believe that would be impossible--or at least I know of no theory of physics or information science that would make that remotely feasible.

No--we would need a universal lander. A small craft, about the size of the now-retired STS orbiter or maybe considerably smaller, that could take off like a conventional airplane, climb to the high troposphere like any airliner, then engage a rocket that would boost it into orbit. That same engineer I mentioned, who talked of building a space-to-space ship in orbit, talked of a landing craft that could also land on and take off from the Moon or Mars.

Mars does have one problem Earth does not have. Its magnetic field is very weak. That would leave anyone on the surface more vulnerable to cosmic radiation. Mars is, of course, much farther away from the Sun than Earth, on average. But still: all cities on Mars would need electromagnetic radiation deflectors, in case of solar flare.

Concerning resource development, the best direction to look in would be beyond Mars, but not much further beyond: to the Galilean Moons of Jupiter, and Titan, the largest moon of Saturn. I doubt you're going to find anything on the other rocks except water ice, and the elements of topsoil--or regolith. The water ice actually would be twice as rich in deuterium as are the oceans of Earth. That applies to every extraterrestrial object. The race would thus be on to develop controlled fusion.

That is interesting.

Me dino looked it up, though it does not say which writer dreamed that power source up.
https://en.wikipedia.org/wiki/Dilithi...
Wikipedia says fictional dilithium crystals can only be found on certain planets (not of this earth?).
If those crystals are not of this earth, that begs a question about a William Shatner Star Trek movie in which the Enterprise goes back in time.
Movie ends with some World War III survivor dude breaking the light speed barrier with that attracting flying by Vulcans to make a close encounter of the third kind.
I do not recall what the light speed barrier breaker used for fuel. Maybe he found a dilithium crystal meteorite like how kryptonite is obtained to be used against Superman.

But it would be a lot easier to jump to Jupiter from Mars than from Earth. Sure, you'd have to wait longer between launch windows. But then you're climbing out of a shallower gravity well and making a shorter transit.

And the side effects could be almost as valuable as the power provided.

That sounds great. Won't get you to Jupiter, though.

The costs for building it in Earth orbit would indeed be too high. So any starship space docks we'd build would need to be near Mars. Mars Planetia does have a ring to it. It is something they unintentionally got right. ;)

But unless we had teleporters or other orbit-to-earth mechanisms a "rescue" mission would be hard to pull off without terrestrial supporters getting them to orbit; a task a bit more difficult than an "underground railroad". Though I suspect there are enough well-funded producers who, upon seeing a free planet where they can thrive, could put the resources behind it.

More realistically we'd be building the tether transport system and/or nuclear-electric "cyclers" not too dissimilar to the one used in "The Martian". I'd expect we'd mostly hold off on operations near Earth for political reasons; no reason to rustle native's jimmies. That said, a pure spaceship with any level of defensive/offensive capability would be a strong defensive play and could generate significant appeal - and fear. Being of the independent-from-Earth mindset we'd most likely use such a vessel to increase our independence in the material sense in the beginning. The less dependent on terrestrial exports we are the better a position we are in for any economic negotiations with terrestrial exporters - and governments.

Though having such a ship could trigger terrestrials trying to build one of their own the sheer cost of it would delay its actual production. It would take them much longer since they would have to ship everything from Earth. Then they would need to develop "space legs": experience which we would already have. I very much doubt there would be much support for launching a nuclear strike against Free Mars.

Even so, we'd be better off with focusing on an orbital defense grid in Mars orbit for a non-aggressive defense posture; only adding offensive capability if the terrestrials got aggressive. It would be rather difficult to launch a sneak-attack from Earth to Mars and any incoming craft would be trackable and almost sitting ducks given the predictability and limited approach orbits and vectors. Of course, our ships that transferred to/from Earth orbit would need some defensive capability as those would be the primary vectors for aggression.

If history is an accurate guide, technological development on free Mars could quickly overtake terrestrial - particularly in the very technologies needed for space travel and defense. A Free Mars space fleet would have the advantage of space-based resources, and thus would be able to have significantly more mass. This mass would be useful for shielding and could be combined with powerful mass accelerators ("railguns") for weaponry if needed. Terrestrial ships would be very hard pressed to keep up - especially with Martian fleet having all the space maneuver experience and adaptation.

Wonder where the idea of "dilithium crystals" came from.

A certain engineer, years ago, put up a page describing a ship modeled exactly after USS Enterprise NCC-1701, but using ion propulsion to drive it, and regular nuclear fission reactors for power. This was his first-generation model. He projected a round trip between Earth and Mars of 90 days--a rapid transit with continuous acceleration, naturally.

Me dino is suddenly thinking of a Star Trek starship that is not powered by fantastical dilithium crystals.

And most of those cases inhabit our government.

Several years ago, a visionary engineer proposed building a space-to-space ship--one that would look very much like the space vessel USS Enterprise NCC-1701 from the Star Trek franchise. What's more, he proposed to build this in geostationary orbit, and use it to fly colonization missions to the moon and Mars, plus at least one exploratory mission to Venus, one rendezvous with a near-earth asteroid, and one long-range explorary mission to the Jupiter system and especially to Europa.

Now if I understand you correctly, the costs of building such a vessel in geostationary orbit would be far greater than the cost of first establishing Martian colonies and then building that super-vessel in low Martian orbit, not Earth orbit.

If we then put this together with the Free Mars proposal, that would suggest the first mission this super-vessel would fly, would be a rescue mission for Earth-bound "producers" seeking to defect. Or did I miss something?

Yes, Mars as a separate polity due to the distance is part of the reason I think it is the most logical choice for a Gulch. "Working Mars" would be too rough for the looters - just as settling the American West was. A rugged frontier just does't appeal to them. ;) You don't have to hide the Gulch if it takes too much for the looters to come after it. History as our guide shows the way - build it, appeal to enough of a base of producers while keeping it too frontier-like to attract looters yet capable of operating as an independent entity, then formalize that independence.

A Free Mars has the potential to replicate at a planetary scale what Free America did at the continental scale. Once I started comparing the possible space ward bound scenarios to history it was quite shocking how close some are. This time around, however, our "Columbus" has to seek the support of producers, rather than governments.

They won't go voluntarily. Radioactive slag would be a more likely fate, albeit with intolerable civilian casualties and unintended consequences.

Yes, I remember that the Martian sidereal day is only a little longer than the terrestrial sidereal day. And the Martian solar day might not be even as much longer, given the length of the Martian year.

We are left only with the longer transit time--which pretty much guarantees that Mars will always be a separate polity.

I doubt one could develop a mobile fusion generator, especially for an aircraft. Let's not conflate fusion power with John Galt's electrostatic motor. (Even that could drive a prop plane, but never a jet plane.)

But a massive power plant to drive an all-electric railway system? That's easy to imagine.

Yeah I'm no fan of Phobos, but it isn't really in the way. Aerostationary orbit is only required for a fully synchronous skyhook. Mars would actually benefit from a low orbit asynchronous skyhook, which is more feasible because it has no existing population.

An async skyhook would provide an additional martian transport system. One that "touched down" every couple hours or so would give you a circumferential up/down navigation sequence. You could thus have multiple settlements which grow to become hubs. Think of it like a train, one that just happens to actual go up and then down instead of across the surface. It would be quite a way to get more out of the investment as you could use it for cross-planet transportation when not using to to launch or receive long-haul cargoes. Personally I think asnyc hooks are a better choice anyway because of the multiple-location aspect.

Regarding asteroids vs. meteoroids I'm going to have to disagree as one of us is using the term incorrectly. My education holds that meteoroids are too small for mining as they are generally only a few meters across, and often much less than a meter. Of course, back then Pluto was a full-fledged planet so that definition may be too old. However, the bulk of the inner and middle belt asteroids are believed/known to be heavily metallic. These are the "Bright S" and "Bright M" class asteroids. The former are composed mostly of metallic iron with silicates such as magnesium (hence the "S"). The latter are primarily made up of metallic iron (thus the "M"). Ultimately, for purposes of rotation mass (such as in a tether), as long you can manage/contain the stresses it doesn't matter much.

Regarding launching from the moon, sure you benefit form lower gravity and no atmo, but it doesn't make up for the costs of building and maintaining a system there. The moon has some distinctly more difficult and costly environmental problems than Mars does - y0u pay a price for having no atmosphere. The mass you have to take to the moon is dramatically more than for Mars. Whereas on Mars you can get away with, for example, with growing food under millimeters of thin plastic on Luna you're talking very thick glass - measured in feet. Of course, the 28 day day/night cycle would pose other problems - problems that preclude solar power for a moon base. Sure you could set up by the poles, but that isn't where the goods are.

Almost everything you need to build that catapult on Luna you have to ship there. Martian rockets and fuel can be built there. The shallower gravitational well means we can can use less energetic (and volatile) fuel quite effectively.

Until we have something like fusion you can't generate the power on the moon to reliably grow food for a population of any significance. This means a lot of money in importing basic goods - a lunar settlement before a Martian one is a financial gravitational well (and probably after, just less of one). However, Mars we already know has nearly all of the resources to build its infrastructure. The only thing you will need to import much of at first is high technology such as computer tech and the more refined materials - all of which tend to be rather lightweight and functionally dense.

Lunar does is another massive hurdle. It gets everywhere. It is ridiculously fine and very abrasive. And by abrasive I mean enough to wear through three layers of space suit boot. It got into everything, causing problems from moving suit arms to "lunar hay fever". Any mining operation will exacerbate this problem radically. Trying to clean it with wet wipes only made it worse due to their charged natures. The thermal swings are very large, which causes additional problems. Even maintaining a consistent temperature range is rather difficult on the Moon just as it is in orbit.

Lunar bases require a massive increase in requirements and mass, for little to no gain and none compared to the Martian environment. Sure, it has h3, but currently h3 has no real value plus to get it you need to ship in masses of h2 and apply metric captions of energy - making it possibly not cost effective. Even before we manage to control fusion, deuterium is already very valuable and Mars has it in abundance.

Looking historically, if Earth is Europe, the moon is Greenland and the Americas is Mars. Sure, it took longer to get to North America than to Greenland, but it was done because that is where the resources were.

In some cases, there have been damn little "mental evolution."

Probably right, but I like homo's better than collectors, current or past. Maybe if we get rid of the collectors, the homo's will work ;)

Just one problem with the skyhook systems on Mars: Phobos is in the way. We'd have to sacrifice it. Frankly, I find that no great loss. Phobos is a captured asteroid.

Why is Phobos in the way? Because areostationary Martian orbit is going to be a lot higher than is geostationary Earth orbit. High enough to coincide with the orbit of Phobos.

And actually I don't propose to mine the asteroids. Meteoroids, yes, but not asteroids. You're going to find nothing there but water (with twice as much heavy water as you'll find on earth) and plain ordinary rock. Mars has the mineral wealth. The asteroids will come in handy when, as, and if we solve the contained fusion problem.

You can get down to Mars, I'm sure, with less delta-V (though the transit time is a lot longer). But how about lifting something up? On the Moon you can build an escape-speed induction catapult. On Mars, you need rockets. That same atmosphere that lets you brake and/or parachute down, is a literal drag when you want to lift something up.

Still, Mars has higher gravity--and if you build a beveled spinning ribbon, you can simulate Earth-normal gravity easily. So the crew won't risk going osteoporotic from a long stay.

Global warming...

Interesting...seems to be a problem with all homo's.
Laughing...