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Comment Re:Idiotic publicity stunt (Score 1) 454

>just proving that the big distance is a very relevant issue.

And yet you have yet to offer any evidence that the distance is an issue. As I have explained, repeatedly, the only thing the distance really changes is the cumulative radiation dose of the travelers. Everything else is pretty much the same regardless of whether the travelers are in transit, or have made it to their destination.

Comment Re:Idiotic publicity stunt (Score 1) 454

And you're not getting the point that, for cargo at least, you're *not* doing anything for 100 days. You're accelerating for a day, and decelerating for a day (probably far less). The rest of the time you're just coasting along. No activity. No wear and tear. Just floating dead in the empty void of space waiting to arrive. Whether that's one day or 99 makes very little difference.

With people, yes, you also have to keep life support running, but that's not going to change at the destination, so it doesn't really matter how long the trip is. As for the trip - we understand space pretty well - it's empty, there's nothing there but radiation, and there's essentially no difference between traveling to Mars, and just circling the Earth in high orbit for an equivalent amount of time. There is zero additional risk - either way you're just killing time floating through empty space without any shielding except the hull. All the elevated danger is at the endpoints - launch and landing. And that's not going to change much regardless of whether you're going to Mars or the Moon.

The ONLY additional risk of traveling to Mars versus the Moon is the prolonged radiation exposure during transit, but even when you land you're only going to modestly reduce your radiation exposure, especially for early colonists without robust, heavily shielded shelters waiting for them (it would take burying the shelters under about 22ft of sand to achieve radiation shielding comparable to the Earth's atmosphere), they're going to be facing heavy radiation exposure at their destination as well during the trip - a few months in transit may inflict a dosage equivalent to a few years at their destination, which sucks, but it was pretty much going to suck regardless. Cancer is likely to be a major problem among early colonists who avoid dying some other way. Life expectancy among colonists is liable to be far shorter than for people who stay on Earth - that can't be helped, frontiers are always dangerous, and this will be by far the most dangerous frontier we've braved. If you're not willing to accept the risks, then I recommend not signing up.

Comment Re:Idiotic publicity stunt (Score 2) 454

The big difference is that, on Earth, you need to be operating continuously over the entire distance, thanks to friction, traffic, weather, and other environmental hazards.

In space, you just set your trajectory and then go to sleep until you get to your destination. We do it all the time when sending probes around the system. There's basically nothing to hit - even when sending probes through the asteroid belt beyond Mars, the densest debris field in the solar system outside of Saturn's rings, and almost entirely unmapped, we just don't worry about it - there's so little material scattered across such a large space that the odds of an unintentional collision are vanishingly close to zero. Even radiation is roughly constant, aside from solar flares. For non-living goods either it can pretty much handle it, or it can't.

The result being that it doesn't actually make much difference whether you're sending a vessel across the solar system or just leaving it in high orbit - the non-fuel costs and risks are roughly the same. And we've gotten good about building hardware that doesn't mind being left "asleep" for years while it coasts through space.

Yes, obviously, if you have people on board you need to keep life support, etc, running, and are dealing with cumulative radiation and risk exposure - but that doesn't actually change all that much once you reach your destination - be it in open space, the Moon, or Mars, you're completely dependent on life support, and are beyond Earth's magnetosphere - reaching your destination only cuts your radiation exposure by about half as the planet's mass shields one hemisphere (well, somewhat better than that on Mars thanks to the thin atmosphere and greater distance from the sun).

Basically, as long as you're living in a tin can outside Low Earth Orbit, it doesn't make a dramatic difference where you are in terms of risk or resource consumption, except for the cumulative biological damage due to microgravity. And while there's some reason to be hopeful, we don't actually know to what degree low gravity will negate those problems, though it seems likely that the higher gravity on Mars will reduce them further than on the Moon.

Yes, since you're being exposed to those risks regardless, it would be nice to not waste time just sitting around waiting to reach your destination, but if you're planning a multi-decade mission, a few months one way or the other isn't likely to make a huge amount of difference. Though, assuming you have inflatable or other "fast deployment" habitats that will offer substantially better radiation shielding than the ship, there's certainly a good argument to be made that you should get into them as soon as possible.

Comment Re:1Million People (Score 1) 486

Have you seen how slow Mars rovers move and how carefully they have to weigh each action, in an environment where if you mess up, there's nobody there to rescue / repair you? Have you seen how much maintenance and consumables is involved in mining?

Do these look like Mar's rovers to you?

The concept that "robots will do everything" is simply not realistic.

Show a little imagination and optimism. With this technology, we could avoid all of the downsides of sending humans to Mars at all. You get your minerals, and nobody is condemned to a miserable life on a frigid, lifeless, airless, irradiated ghetto. How is that not a good outcome for everyone?

Do robots do everything for the astronauts on the ISS? Of course not; the astronauts there are basically glorified construction workers and lab techs. Why?

The ISS is just floating there doing nothing. Meanwhile, robots are exploring the outer reaches of the solar system. Landing on Titan. Snapping pictures of Pluto. lassooing comets. Why do we send robots instead of humans? Because they are better.

It's certainly an arguable point as to whether it's worth the cost sending humans in the first place - but once they're there, there's no debate at all about whether it's cheaper to use their labour or to engineer, build, and send robots to do the same task.

No that's right, there is no debate - robots win every time.

Comment Re:Commodore engineers (Score 3, Informative) 265

Not just Irving Gould. Ali Mehdi was just as greedy personally, and penny-pinching in running the company. When engineers proposed the A3000 with a 68030, he personally called them up to ask whether the 68030 was truly necessary, if there weren't cheaper components that could be used

Comment Re:Pay your fair share! (Score 2) 180

        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:1Million People (Score 1) 486

Commodities that you dig up (apart from the problem of how machinery of that size could be transported to Mars) don't require humans to be on site. Even on earth, on site presence of humans is kept to an absolute minimum. So if some consortium wanted to transport minerals or bulk stone from Mars, and they are somehow able to overcome the negative cost:benefit ratio (still orders of magnitude away) then they don't seme to have any reason to rely on a Mars Colony.

1. They don't have to ask the mars colony for permission to mine remotely

2. The colony could probably not reach any veins of interesting minerals because there are no roads, energy is limited, you can't fly (without air) and you can't camp remotely because of the need for pressurized vessels to live in and the radiation levels which require shielding, They are really limited to the area that they could walk or drive to in a day (say 250 km^2).

3. A mine remote from the colony has no reason to be financially attached to the colony, and earth resident company could run the whole thing from earth. so they don't need to pay the colony any money.

All in all that suggests the human colonists aren't going to be competitive with robotic miners, and thus can't make money by mining.

Comment Re:1Million People (Score 1) 486

Perhaps a new colony forced to live in a very special environment will create a civilization that places value and wealth on working together in order to survive to achieve the ultimate goal of exploration for a generation or three.

There has to be a reason why, in the long term, people would want to live on Mars. After a few thousand people have done it, it loses it's novelty - like flying has lost it's novelty and now relies on the utility of traveling quickly from place to place to be viable.

There isn't a rush to live in the earth's remote places - the Simpson desert, or on oil rigs, or remote islands off the coast of Antarctica. That's because once the novelty of remoteness dies off, people need other motivators to live there.

Those motivators are missing for Mars, which is a far less friendly place than a desert or remote island.

Comment Re:Better to dream big than not at all (Score 2) 486

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) 180

>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) 454

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) 486

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.

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