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Comment Re: The treaty says no such thing. (Score 1) 114

You know, you post as AC but it's really obvious who you are, you have the same writing style everywhere you post ;)

Anyway, here's what the treaty actually says:

Outer space, including the moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.

Any questions?

Comment Re:The treaty says no such thing. (Score 1) 114

The missing part is making explicit that an entity owns what it mines and has the right to work the mines it develops. I think given the context it's pretty clear that this was expected, but it is an oversight. You know, if one corporation spent billions clearing the overburden off an asteroid, then another company comes in and just starts mining the ore in question... that's a big problem. It needs to be controlled. Really, it should be allocated out in blocks, with exclusive rights given to use the blocks but only if they're actively working those blocks within a certain timeperiod from their last renewal.

On Earth this is done by nations auctioning off resource extraction rights, but since there's no national ownership of territory in space, no nation could rightfully profit from selling off resource blocks. Blocks would either have to be free or for profits go to an international fund. In the early days, since nobody knows whether space mining actually will play out to be profitable at this point in time, one would expect them to start out free.

But of course all of this would require a new treaty.

Comment Re:The treaty says no such thing. (Score 1) 114

Things don't always come down to that. Look at the Cod Wars between Iceland and the UK. Three times Iceland pushed the UK - a nuclear power with hundreds of times its population - back further and further out its shores. The UK had the military ability to crush Iceland like an ant. But Iceland succeeded by combination of making it economically unfeasible for the British to fish Icelandic waters (net cutters, for example) and well-played international geopolitical maneuvering (for example, threatening to give the NATO base at Keflavík to the Soviets if the US didn't exert pressure on the UK, while also successfully positioning itself as a small weak state being bullied by a large powerful one)

Anyway, the Outer Space Treaty was well meaning. Think of the context of the Cold War and how that was all playing out. It seemed logical to think that both nations would begin laying claim to various bodies (or parts thereof), say by landing as many landers as they could to them... which would inherently lead to disputes, just like happens with worthless pieces of land on Earth - with the each side supporting their claim by military means, just like happens on Earth. It was seen as a ripe grounds for an unchecked military escalation, and while it would start out on other celestial bodies, it would progress to LEO and GEO, and then to Earth.

They were probably way overly optimistic about the space of advancement in space technology (remember, this was 1967) and overly pessimistic about everything else. They certainly weren't trying to "block commercial mining"; the goal was simply to prevent a space arms race between rival powers. Quite to the contrary, the treaty talks frequently about encouraging the peaceful use of space for the benefit of humanity. There's just one detail missing, which is to make explicit that corporations or individuals own what they mine. Without that, there won't be much of any "use of space" beyond exploration.

Comment Re:The treaty says no such thing. (Score 2) 114

Getting things *to* locations in space is inherently expensive. The cost of getting them *back* is not inherently so, if you don't insist on each return having a custom reentry vehicle and instead just shape it as its own reentry vehicle, with full expectation that it'll suffer some ablation during atmospheric entry. Some NEOs have only dozens of meters per second delta-V to reach earth intercept with an optimal trajectory and timing - a good baseball pitcher could do that unaided ;)

Comment Re:Problem with the definition of a planet (Score 3, Interesting) 57

They'll say, "oh, it's okay, there's enough of a size difference between those bodies that they don't count". But the thing is that there's no way that most of the current "8 planets" would have cleared their orbits without help from the giants. It's pretty much accepted science in astronomy that Jupiter, and to a lesser extent Saturn, scattered most of the bodies in our solar system. Mars has a Stern-Levison parameter (rating of the ability of a body to scatter small bodies) two orders of magnitude less than Neptune, and Neptune has multiple Pluto-scale bodies in its orbit. Pluto may be small compared to Neptune, but it's not so small in comparison to Mars, yet Mars has two orders magnitude less ability to scatter them. Mars didn't scatter these things away - Jupiter did. Heck, a number of the models show that the planets didn't even form in their current locations.

There's all this misuse of the Stern-Levison parameter out there to say things that it doesn't. The parameter is based around a probabilistic simulation of the body and a bunch of "small bodies" with a mass distribution and orbital distribution similar to our asteroid belt. But of course, that tells you very little - our asteroid belt only has the size and mass distribution that it does today because of the influence of other planets - and when I say "other planets", I really mean overwhelmingly Jupiter (only a tiny fraction of asteroids are in Mars resonances). Jupiter has stopped these bodies from coalescing into larger bodies and scattered the vast majority of its mass elsewhere. That's not the situation that the solar system was in during formation. There were numerous large "planetissimals" scattered around. The Stern-Levison parameter says absolutely nothing about the ability of a body to scatter large planetissimals. And even concerning scattering asteroids, it doesn't state that the scatters are enough to "clear the orbit", only that their angle changes on a pass by more than a given number of degrees.

Basic point: a standard based around the "8 planets" having cleared their orbit is a lie. The science says that most of them aren't responsible for clearing their own orbits.

And while we're at it: what sort of stupid standard puts Mars and Jupiter in the same group but in a different group than Pluto and Ceres? There was a perfectly reasonable standard under discussion at the IAU conference shortly before they switched what they were voting on: a definition built around hydrostatic equlibrium. A lot of the planetary scientists left thinking that this was the version that was going to be voted on, and being happy with either "no definition" or an "equilibrium definition", saw no need to stick around for the final vote. Hydrostatic equilibrium actually is valid science, and it's very meaningful. A body not in hydrostatic equilibrium is generally made of primordial minerals. It's the sort of place you'd go to research, for example, properties of how the solar system formed. A body in hydrostatic equilibrium has undergone mass conversion of its primordial minerals to new forms. It's undergone massive releases of energy (which may still be present, depending), associated action of fluids, etc, and are the sorts of places you would go to study mineralization processes, internal processes or search for life. They're very different bodies, and there's a very simple dividing line - one that's much easier to calculate/measure than a pseudoscience "cleared the neighborhood" standard.

Comment Re:Or just make the diesels hybrids (Score 2) 181

And even the best public transport system generally isnt going to start and stop *exactly* where you need it, so there still is going to be *some* walking. Which some people with disabilities or health problems simply can't manage. And to achieve a good public transport system - with frequent stops, densely placed stops, relatively direct routes and affordable prices - is entirely dependent on population density far more than it is on "will". In places with high density, it's a relatively straightforward process to have a good public transport system. In places with moderate to low density, it can be difficult to nearly impossible. And weaknesses in public transport system are a viscious cycle: the less frequent the stops, the further spaced out they are, the longer the transit times, and the more expensive the rides - the fewer people will ride them. The fewer that ride the less frequent you have to have the stops, the further apart they need to be, the less direct the routes, and the less affordable the prices.

Comment Re:Cost of access is key. (Score 1) 345

That was not my point. Ofc we can improve ISP. No idea how much that improves either 'performance' or drops price.

It improves performance a *lot*. As for price, it depends on how expensive that rocket system is. For first stages, an improvement in ISP's effect on the size of the rocket isn't that much greater than linear. But the further up the delta-V chain the engine is used, the more of an impact it has on everything that was used to get it there. An extra hundred sec ISP on a first stage might reduce the system mass by a third; on a second stage up to LEO, maybe cut it in half; on a kick stage for a Mars transfer orbit, maybe cut it by two thirds. On an ascent stage from the surface of Mars... well you get the idea. Shrinking down a rocket to a small fraction of its size - fuel, tankage, and engines - well, that's really significant. ISP is very, very important for upper stages. So you can afford to pay quite a bit for those top stages if it improves their performance. Just not an "unlimited" amount.

There is no way a high tech electrical engine will improve its performance by 10% regardless how much money or time you put into it: the efficiency is already between 98.5% - 99.5%, up to 99.9% in some cases.

This is getting a bit offtopic, but at least the electric engines in EVs don't usually run at nearly that high. Depending on the type they might average 85 to 94% on average. It varies over their load cycle.

Regarding rockets: there is simply not much margin anymore in changing the form of the exhaust tube, burn chamber etc

Actually you can. The general principles of how rocket engines work are fixed, of course - your exhaust will never exceed its local speed of sound in the throat, and then you want to expand it as close to ambient pressure as you want. But the details vary greatly. There's bell nozzles, linear nozzles, annular nozzles, aerospikes, throatless nozzles, atmospheric wake compression, and on and on. There's tons of different ways - developed, in development, and in theory - to pump and inject your propellants - where they need to be pumped at all. Even many propellants that are traditionally thought of as being in one state can be implemented in other states. There's various ways - developed, in development, and in theory - to prevent nozzle erosion. To improve regeneration. To reduce mass. And on and on and on. Rocket combustion is a rather complex thing and we're still trying to get a handle on it. Do you know that we still really don't know how aluminum burns in solid rocket propellant? There's something like five different competing theories. I mean, things like this are a Big Freaking Deal(TM), especially when such small improvements in upper stage ISP have such significance for lower stage mass. And even on your lower stages there's a lot of things that have a big effect on your system cost. For example, how to stop resonant shocks from ripping them up - a lot of people don't realize that one of the main benefits of adding aluminum first stage to propellant mixes is that the droplets of burning aluminum damp shocks. (yeah, it increases ISP too by raising the exhaust temperature, but it also has disadvantages, such as not contributing to expansion, slowing down gases (particularly near the nozzle), and impacting/eroding the throat (or even forming an accumulating slag)

Re, nuclear+chemical. There are proposals for this. The main issue isn't efficiency - the extra chemical energy doesn't make that much of a difference - but thrust. The downside to nuclear thermal is that the reactor is so heavy (fission is like that, unfortunately) that the mass ratio is only something like 3-4:1. That's really bad (you generally get 15-20:1 or even better for a chemical first stage). So the approach is to inject oxygen early in the ascent phase for added thrust, but only run on hydrogen higher up when gravity losses are lower. I'm really not that sanguine about nuclear thermal rockets getting a serious development program any time soon, though. The public overestimates the risk, of course - not only am I sure they'd well seal the fuel elements against whatever damage would be incurred by explosion or reentry, but there's the simple fact that the fuel is "fresh", not contaminated with the more hazardous actinides. But it's going to be a hard sell. And a really hard development project, if they ever did try again. Gigawatt-scale flying nuclear reactors that pose radiation hazards during assembly and test aren't exactly childs' play.

Comment Re:The guy aint no Sagan... (Score 1) 345

You forgot to exclude operational expenses.

Yes, people to run robots and comm time on the DSN. We're not talking about massive expenses here. The real expenses are the capital costs.

And also didn't mention that you can't just lob chunks of metal straight to Earth's surface,

Actually, you really just can. Even random rocks from space - not shaped for optimal entry shape, not cemented together by anything yet what nature chose to gie them - do this all the time. They have to be between a certain size range (too little and the whole thing ablates; too large and it explodes, either in the atmosphere or on impact), but the random creations of nature do it; delberately shaped and sintered projectiles should have no trouble with it, with (proportional to their mass) relatively little burnoff.

You would, of course, need a rather large area designated as the impact area; even with very precise aiming, by the time they get to Earth and undergo reentry the random variables will spread them out over a sizeable chunk of land. A large salar might be ideal, since they get resurfaced periodically so the impacts wouldn't be damaging the landscape.

By your same logic, the mining of minerals on Earth would be zero dollars per gram if the equipment was solar powered and automated

It's almost as if I didn't discuss capital and ongoing costs in my above post.

Launch costs really are key to the rate of development at the very least, in that they limit the rate in which funding can be raised for the necessary exploratory and test craft to be launched. Even if the economics for operating a mine on a NEO works out really well at present launch costs, you have to prove that you can do it before you can raise the billions to build it. And to prove that you can do it you have to launch a number of missions while you're still relatively poorly funded. They face the same problem that Bigelow has faced - a probably reasonable business plan but the early phases hinging around factors that they don't control.

It does nobody any good to pretend that the lack of a space economy is because investors are cowards and morons

I think you need to go back and read my last post again, particularly all of the "it's too early to say"/""we don't know"/"but time will tell"/etc lines. I'm not saying that at all. I'm saying that there very well could be a compelling case for asteroid mining even without any radical changes in space technologies. But there's a great deal of work to prove that before we can get to that point.

Comment Re:seriously? (Score 1) 83

Are the other variants more dialectal? In addition to huoji ( / ) (fire chicken) what I read states that there's also qimianniao ( / ) (seven-faced bird), tujinji ( / ) (cough up a brocade chicken) and tushouji ( / ) (cough up a ribbon chicken)

(hope Slashdot doesn't mess up the characters)

Comment Re:seriously? (Score 1) 83

On the other hand I would want to talk to Archimedes

You speak ancient Greek and can communicate with the dead? Okay, I'm impressed. ;)

Thanksgiving trivia for the day: the word for "turkey" comes from extensive and long-running confusion about where the bird came from. For example, in English it's called Turkey. In Turkey it's called "hindi", referring to India. In India it's called Peru. In Peru it's called "pavo", referring to peacocks, which are native to south and southeast asia, such as India (cyclic there), Cambodia, Malaysia, etc. In Cambodia (Khmer) it's called "moan barang", meaning "French chicken", while in Malaysia it's referred to as "ayam belanda", meaning "Dutch chicken". Both of those in turn think it comes from India: in French it's called "dinde" (from "poulet d’Inde", aka "chicken of India"), while in Dutch it's "kalkoen", referring to a place in India. Greek has a number of local dialectal names, such as misírka, meaning "egyptian bird", while in Egypt it's called dk rm, meaning the Greek bird (even though the latter part of the name derives from Rome - the Italians, by the way, thinking it comes from India). One variant of Arabic even credits it to Ethiopia.

A couple languages deserve special credit for their words:

Best accuracy: Miami indian - nalaaohki pileewa, meaning "native fowl"
Worst accuracy: A tie between Albanian (gjel deti, "sea rooster"); Tamil (vaan kozhi, "sky chicken"); and Swahili (bata mzinga, "the great duck")
Most creative: Mandarin - many names with meanings such as "cough up a ribbon chicken" and "seven-faced bird"
Least creative: Blackfoot: ómahksipi'kssíí, meaning "big bird". Hmm...

"Consider a spherical bear, in simple harmonic motion..." -- Professor in the UCB physics department