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Comment Re:Pay your fair share! (Score 1) 163

        the use of violence and intimidation in the pursuit of political aims.

Sounds like a pretty accurate description of, say, violent groups firebombing abortion clinics to advance extremist medical policies. Or burning crosses and even churches in an attempt to drive ethnic minority populations out of a region.

I could go on, but I doubt I'll convince you anyway.

Comment Re:Better to dream big than not at all (Score 1) 461

Umm, is that supposed to be a joke? Or have you just never actually paid much attention to the moon?

The monthly cycle of the phases of the moon are the result of it's month-long day-night cycle. The part of the moon that's bright is in daylight, the part that's dark is in night, and just like Earth the day-night cycle sweeps across the entire planet. The "dark side of the moon" is poetic license for the side that faces permanently away from Earth, not unlike calling Africa "the dark continent" - referring not to the absence of light, but the absence of knowledge about it.

Comment Re:Wherever data is collected, it is abused (Score 1) 163

>Bastardy is still a thing and will be forever.

Now you've got me wondering - was bastardy actually an issue in cultures where inheritance was passed down the matriarchal line rather than the patriarchal one? I mean it seems that the entire point of formal recognition of bastardy versus "legitimate" children was recognizing that people slept around, but inheritances needed to go to the "right" children.

Comment Re:Idiotic publicity stunt (Score 1) 387

Unless you're in a hurry, distance is largely irrelevant for transporting stuff around the solar system, what matters is specific orbital energies. You typically only burn fuel at the very beginning and end of the voyage, when angular momentum changes per unit fuel are at their maximums, the rest of the time you're just coasting, so there's no added cost for non-perishable cargo. Sending people adds a bit more of a hurry, but it sounds like Musk's plan is currently not to worry about it overmuch, potentially even just using a standard Hohmann transfer orbit between Earth and Mars orbits (optimal fuel usage).

Risks are different, but the Moon is far more challenging, as unlike Mars it has no readily available air or water, and razor-sharp unweathered dust that will make short work of air seals and moving parts.

Space travel really does offer the quintessential perpetual motion machine. In fact, if you're not concerned about transit time at all, you can get from Earth orbit to pretty much anywhere in the solar system almost for free, using the so-called Interplanetary Transport Network of gravitational slingshots and Lagrangian "keyholes" to control your speed and direction while consuming almost no fuel. It can easily take years or decades to get where you're going, but if you're willing to wait the shipping rates can't be beat, and it's been used repeatedly for getting probes into the outer solar system.

Comment Re: H20 (Score 1) 461

How do you prove ice or CO2 "viable"? They're either there, or they're not - every molecule is identical to every other (aside from slight isotope variations). And we know they're there. Distillation might be required to remove hazardous impurities from the ice, but atmospheric analysis already shows the CO2 to already be over 95% pure (okay, not laboratory pure, my memory apparently slipped in an extra 9), with the rest being mostly nitrogen and argon, with about 0.1% oxygen and carbon monoxide, and slight traces of other substances.

Comment Re:Better to dream big than not at all (Score 1) 461

Actually, I seem to recall that Mars is within the range as well, though the safety margins would be (much?) smaller. You also already have a nice big counterweight already almost in position on Mars, in the form of its outer moon, which is very nearly in "Mars-stationary" orbit (though the existence of it's inner moon would present some challenges)

On either world though, while it would be within the limits of current material science, I'm less sure it would be within the range of current engineering ability. Certainly it would not be anywhere remotely near the first project you'd undertake - you'd want a thriving self-sustaining industrial base on site first.

Consider, the orbital dynamics demand that a Lunar elevator extend at least a little beyond the Earth-moon L1 or L2 points, meaning you'd need to build a 60,000 km long tether - long enough to wrap one and a half times around the Earth. It would be by far the largest engineering project ever undertaken by humanity. Building self-contained cities on both planets would likely be a cakewalk in comparison.

Where space elevators are concerned, skyhooks are a much more realistic option - far smaller, far simpler, far lower demands on materialproperties, and with no moving parts they act as roughly 100% efficient momentum "batteries" to transfer momentum between launching and landing vehicles. On the moon you could even theoretically build them to grab stuff right off the surface and hurl it on a transfer orbit to either Mars or Venus. (Ironically, assuming the lower end is near the surface and syncs with surface speed, the smaller the skyhook, the more powerful it will be)

Comment Re:hmm.. (Score 2) 387

Being prepared for the possibility of death is a suicidal streak? So, every soldier and explorer in the history of the world has been suicidal?

I think it would be at least as honest to say that such people simply need to recognize a goal as being worth spending their life on, if necessary, rather than remaining in the comfortable delusion of immortality that many people wrap themselves in, some even unto their deathbed.

Comment Re:All good, great, and fine but.... (Score 1) 387

The moon is attractive primarily as an orbital fueling/industrial base for Earth, and would be almost entirely dependent on Earth for support for the indefinite future as it lacks readily accessible environmental resources. Plus you have to deal with razor-sharp unweathered moon dust rapidly destroying air seals and moving parts.

Mars in contrast has millions of cubic miles of easily accessible water ice, and plentiful CO2 in the atmosphere - the bulk ingredients needed for growing a biosphere. Add some algae and a bit of fertilizer, and you can grow biomass just as fast as you can build greenhouses. A job for which nanoncellulose has some small potential - translucent, gas impermeable, easily moldable, and roughly as strong as aluminum. And it can be made from biomass using only thermal and mechanical processing, leaving the "waste", including all the trace elements, ready for reuse as fertilizer for new growth - the cellulose itself is built only from the elements in water and CO2.

In addition, the Moon is only a little closer in terms of energy (=shipping costs) - the difference in distance primarily boils down to longer travel times. And there's no reason to believe landing would be substantially easier on the moon - it has a shallower gravity well, but lacks an atmosphere for aerobraking from orbital speeds. And at lower speeds, as landing approaches, both worlds are essentially in vacuum.

That said, I would rather expect test landings on the moon simply to guard against unexpected difficulties of landing on minimally unprepared surfaces in vacuum. But that's just a engineering test, not a large scale plan in it's own right.
s a development detail, not a

Comment Re:H20 (Score 1) 461

Well, the water is pretty much literally right there to be picked up - cutting ice is a fairly well developed technology that shouldn't be heavily impacted by doing it in vacuum. And CO2 is even easier - it's everywhere, and existing vacuum pumps will have no problems collecting and concentrating it.

As for converting it to biomass - plants are extremely adept at converting water and CO2 into oxygen and biomass. And microbial ones like algae can reproduce exponentially over very short timescales, allowing you expand production just as fast as you can build greenhouses and collect the necessary trace elements.

You talk as though there's something magically more difficult about using mature technologies just because you're on another planet. Once you're inside an artificial pressurized habitat, the only immediate differences from being on Earth will be the strength of gravity, and the view out the windows.

Comment Re:The Moon is first (Score 1) 461

Except that the Martian wind also wears the dust nice and smooth, unlike the razor-sharp moon dust that will make short work of moving parts and formerly airtight seals. If the wind had any force behind it it might be a problem, but as you say the dust will get into everything either way, so the only real problem is the reduction in visibility and insolation due to dust storms. Sandblasting would seem to be a problem, but due to the extremely low wind force and correspondingly fine particle size, it's probably only an issue for transparent surfaces, which would need some sort a protective coating.

Nigh-limitless CO2 delivered to your doorstep is also a valuable Martian resource - needing only to be fed into greenhouses to be converted into oxygen and (with water) construction feedstock. Nano-cellulose for example is translucent, gas impermeable, easy to sculpt when wet, and roughly as strong as aluminum when dry. Also food-safe (it's used as a thickener) and compostable. And of course carbon has numerous other uses as well.

>That's much easier than waiting multiple months.
Only early on, or if you have a relatively leisurely and easily fixed disaster on your hands. Evacuating a colony of any size would likely be impossible either way, and any critical parts presumably already have spares standing by. Which pretty much leaves emergency supply runs of food, water, or air. And Mars has water and air available locally with minimal processing. Medical evacuation in case of problems beyond the expertise and technology available locally might be a nice option for a few individuals, assuming they could survive the return to Earth's gravity (and crushing acceleration of the trip), but it's absence is hardly a catastrophe beyond the personal level.

Comment Re:The Moon is first (Score 2) 461

Unfortunately, the problems are considerably more difficult, and the transportation costs almost as high. All the moon buys you is faster transit times, which is only relevant if your need for help can wait for several days.

The moon is interesting primarily as a fuel, and perhaps eventually construction base, conveniently near (energetically) Earth orbit. And perhaps as a location for major radio telescopes on the far side, nicely shielded from Earth's radio noise. Mars is practically Earthlike in comparison.

Comment Re:What kind of drugs (Score 1) 461

Well, first we'll have to calculate just how many cannabis brownies will be needed to last 100 people for 80 days...

And where are you getting "one way" or "survival of the fittest" from? The current plan is to re-use the transport ships many times, with free return passage to anyone who wants it on the returning ships. And colonizing a new world is likely to be a deeply cooperative endeavor - humanity hasn't been particularly "survival of the fittest" since we started pre-chewing food for our elders.

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