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Comment: Re:Terraforming potential? (Score 1) 134

by Rei (#49781309) Attached to: How To Die On Mars

My favorite approach is to build floating solar towers on Venus or the gas giants - big chunks of greenhouse material shaped like an inverted funnel reaching out into space. Unable to radiate its IR radiation back to space, the air under the funnel would become hotter than the surrounding atmosphere and rise (imparting lift to the funnel without even requiring a lifting gas). Due to the size, drag against the funnel surface would be irrelevantly small. As the funnel narrows, the gas velocity would increase - with a large enough funnel, to well over escape velocity. The funnel could be moved and aimed to some degree by directing part of the flow out through adjustable side jets. If the funnel was shaped so as to cause the gases to spiral and then flare out at the end, you could centrifugally sort the gases out by atomic mass, and thus for example rob light gases (such as water and nitrogen) of escape velocity while allowing heavy gases like CO2 the energy to escape.

Venus could send CO2 on a Mars intercept trajectory to raise its temperature and pressure. Jupiter could send hydrogen on Venus and Mars intercept trajectories, for Bosch water generation. Large moons and dwarf planets could be similarly seeded.

Of course, the obvious question: will this, or any other form of terraforming begin any time in the next many-hundred years?


Comment: Re:Radiation not a problem, an opportunity (Score 1) 134

by Rei (#49781239) Attached to: How To Die On Mars

The sad fact is, the first colonies will probably be build right out in the open on flat land with nothing around for dozens of kilometers, because it's safer to land there. Which is why we haven't landed any Mars probes in deep canyons or the like, despite all of the interesting geological formations that would be exposed on the walls.

Comment: Re:Hobbit (Score 2) 134

by Rei (#49781201) Attached to: How To Die On Mars

I love how these things are all "you simply have to do..." Like one goes out and collects the atmosphere with a butterfly net and splits it with a butcher's knife. Or like just goes and "gets a smelter and a foundry going".

Do these people have any clue how complex these sorts of industrial systems are? They have hundreds of thousands of components, all of which can break, and some of which are massive. The more you scale it down, the less efficient it becomes. And systems engineered on Earth don't just magically work on Mars too. You can't just dump heat into a river or the air, your gravity is significantly lower, and you've got electrostatic dust that clings to everything. And everyone output feedstock you want requires half a dozen or so input feedstocks, not counting all of the parts that can break - and they will break. And not all of these feedstocks can be gotten from the same location.

Let's just pick one little part of what you just wrote. "pass the CO over iron oxide dust" (we'll ignore everything leading up to getting and transporting that CO2). First off, if you literally do just that, you'll get nothing. The reaction needs to be done *hot*. And it can't be just "passing it over", it has to be thoroughly mixed. But then you get ready-to-use steel right? Wrong. Because you don't have "iron oxide dust". First off, you don't have any fine "dust" in mineable quanties, the blowing surface dust is spread over overthing, not accumulated in big pits ready for you to dig up.You at best have sand; at worst, solid rock. Most sands are not going to made of a majority iron oxide (if they have any sizeable quantities at all). Iron ore deposits are places where iron has been *concentrated* by geological processes, it doesn't make up the majority of basalts. And even cementations of iron-rich clay concentrates aren't 100% iron oxide. Whatever you mine (which means mining equipment, which means big, expensive, complex devices), you need to break it up, which means rock crushers, (which mean big, expensive, high wear devices), transport (haulers - more expensive devices), etc. At the mill it's going to go through a range of hoppers, conveyors, etc, all of which will wear and break. In addition to your ore and CO, you need a wide range of fluxing agents to separate out the stuff you don't want and to produce a usable product. The most critical of your fluxing agents is limestone, which on Earth mainly comes from deposits of marine microorganisms. Fat lot of luck finding that on Mars. So you need to mine less common calcium carbonate sources like travertine. More mining equipment. Hey, do you expect to find your travertine ten feet from your iron ore? Yeah, best of luck finding that, you've got to drive! Just hope you don't have to drive hundreds of kilometers, eh? Of course that's just one of a variety of fluxing agents you'll be wanting to add, there are many, for varying purposes. Anyway, once you've got your big molten mess (consuming ridiculous amounts of energy, orders of magnitude more than we've ever fielded offworld), you need to do something with it as you stream it out. Okay, then of course you have your slag skimmers. Hey, how long do you think that parts dripped in a stream of molten iron last? And you need to do something with your slag, so get your equipment to haul it away (after you've cooled it) ready as well. Speaking of cooling, normally we'd use water for that and just let it boil off for cooling, but on Mars it's a precious commodity, so go add more complexity for recapture and cooling! So now we've got a stream of mostly pure steel, but we're not even CLOSE to having usable parts.... (I'll stop here, as I don't want to spend all day on this).

I get it, you have a basic understanding of the chemical formulas for making a couple products. Well, here in the real world, a simple chemical formula is not enough. Real world processes are far more expensive and complex. They don't just pop together by waving a magic wand where you say, "you just do X and Y, and poof you have a habitat!"

In the real world, we're not even 1% of the way to the point where we could set up a working steel mill on Mars. Not. Even. Close.

Humans living on Mars can't just "bootstrap" themselves like some sort of colonist stepping off of the Mayflower. They're entirely dependent on modern technology just to live. Well, unfortunately, modern technology is produced by extremely complicated global supply/dependency chains. You can't just chisel a CO2 scrubber out of a chunk of granite.

Comment: Re:Hobbit (Score 1) 134

by Rei (#49781079) Attached to: How To Die On Mars

Indeed, it's far easier to build a hab on Earth that you know will work and launch it. We're about as close to being able to build complex structures on Mars out of local materials as we are to being able to send a probe to alpha centauri: vague, general ideas with little real-world engineering and no practical experience.

Even the simplest "local materials" concept - building a hab on Earth with the structural strength to bear a thick layer of regolith, launching it, then dumping the regolith on top - requires engineering, launching and landing a "martian excavator", which would be a multi-billion dollar program. Certainly more expensive than say the Curiosity rover. I'd wager in the 5-10 billion range, after all is said and done (not counting the hab itself).

Or were they picturing people spending half a year outside in space suits working with picks and shovels and burning the caloric equivalent of many tonnes of food and other consumables and wearing through their space suits, all while being exposed to a high radiation flux?

Comment: Re: This seems foolproof! (Score 1) 74

by Rei (#49780743) Attached to: Russian Space Agency Misused $1.8 Billion, May Be Replaced

I counted four lanes, but you're right, it's actually only two lanes, the other half is a rail line. So half of what I accounted for being rail rather than road totally justifies $60k per square meter!

And bridges! Wow, no road has ever included bridges before! We're not talking the Danyang–Kunshan here, they're little bridges over a little river. And the terrain of the valley bottom would be considered "flat" by the standards of many countries, such as Japan. I drive on roads with more elevation change than that every time I go to my land.

There's absolutely zero reason for a 28 mile road through the countryside to cost 9.4 billion dollars. None. The longest road tunnel in the world is over 15 miles long and cost a grand total of $113 million. In Sweden, where wages are tenfold what they are in Russia.

(Lastly, I have no clue what you mean by "original source video". )

Comment: Re: This seems foolproof! (Score 2, Interesting) 74

by Rei (#49778525) Attached to: Russian Space Agency Misused $1.8 Billion, May Be Replaced

That's true - olympic medals are only required to contain a minimum of 6 grams of gold, and at least 92% silver. Even still, it's a an incredible price

$9.4 billion for a 28 mile road. And we're not talking through an urban area, just simple new constuction. 4 lines. 28 miles. 45000 meters long with an actual driving width of... oh, let's say 3,5 meters per lane? Not sure what's typical. So about 157500 square meters. $60k per square meter. I mean, seriously, just think about that. You could stack $1000 Louie Vitton handbags 5 layers deep across the whole road for that money. $9.4 billion for 28 miles? You could pay Russians $3 an hour to carry passengers on their shoulder at 3 miles per hour and carry 50 thousand passengers per day every day and it wouldn't cost as much as the road for nearly 20 years.

Comment: Re:Corruption? In Russia? (Score 1) 74

by Rei (#49778303) Attached to: Russian Space Agency Misused $1.8 Billion, May Be Replaced

Really? That's your example of something comparable to Roscosmos embezzling 10% of its annual budget? Operation Lightning Strike which turned out to be a big entrapment op that spent years trying to convince non-key players to commit crimes that they never would have otherwise, and a link that's anything but an endictment of NASA?

Comment: Re:This seems foolproof! (Score 3, Insightful) 74

by Rei (#49778067) Attached to: Russian Space Agency Misused $1.8 Billion, May Be Replaced

This is, after all, the same country whose 28 mile road to the Olympics cost more than if they'd covered the whole road with gold medals two layers thick. ;)

Concerning this privatization, the only question that remains is, which friend of Putin is going to get to "buy" the space agency at a " fair market value" ;)

User Journal

Journal: Verbiage: Some puns (2)

Journal by Chacham

As if Some puns wasn't bad enough, i shall here continue my plagiarism, brevity, and literary destruction:

Mick Jagger's dog asked his friend, Patricia Whack, for a loan, offering a small item as collateral. Puzzled, she asked her husband what it was. "It's a knick knack, Patty Whack. Give the dog a loan. His old man's a Rolling Stone."

Sixteen sodium atoms walk into a bar followed by Batman.

Comment: Re:I'll believe it when I see it... (Score 1) 117

by Rei (#49767671) Attached to: India Ends Russian Space Partnership and Will Land On the Moon Alone

Its not that simple. You can't just recover it from nuclear reactor waste because it's mixed in with other isotopes of plutonium, and isn't in that great of quantities to begin with. So first off you have to reprocess nuclear waste to extract the neptunium - which again, itself isn't in very great quantities, it takes a lot of waste, and most places don't want to do waste reprocessing to begin with due to cost and liability issues. You then have to make neptunium targets and expose them to a neutron flux - that is, using neutronicity that could otherwise be used for power generation or other valuable purposes (it takes a lot of neutrons to make a tiny bit of Pu238). Pu238 should be more thought of as a manufactured product than as a byproduct of particular types of nuclear reactors.

There are a few other candidates for use as space power sources that actually are waste products, but they're all significantly worse performers. There are two other alternatives. One is to make a Sterling RTG, which was in development, but funding has been cut off (it's also kind of tricky because you have to ensure that something with moving parts will operate for decades in the harsh environment of space). The other is to make an actual nuclear reactor. This means almost limitless power, but it comes at the expense of not only massive development costs and public opposition, but a large minimum size and massive radiator requirements, as well as the same reliability challenges of sterling generators.

There's no easy solutions. Except, of course, to stop bloody wasting plutonium once we have it.

Comment: Re:I'll believe it when I see it... (Score 4, Interesting) 117

by Rei (#49764673) Attached to: India Ends Russian Space Partnership and Will Land On the Moon Alone

"Love" is the nice way to put it. "Largess at the expense of all other solar system exploration" would be more accurate. Here's a graph. And it's always the same stupid justifications - how many times can we pretend to be excited about "revelations" that Mars was once in its past a wet place? Or that we're going to stumble into life any time soon in its perchlorate-rich, destroys-organics-on-contact regolith?

And it's not just huge amounts of money that they're wasting - they're also throwing away most of the remainder of our plutonium supply. At least there's money to start making it again, but it'll take time. Plutonium is precious, and it's needed for outer planet missions.

Comment: Re:Twenty five years of science destruction... (Score 2, Insightful) 117

by Rei (#49764639) Attached to: India Ends Russian Space Partnership and Will Land On the Moon Alone

I hate to be the one to tell you but academia generally pays poorly outside of the US. More so in a country like Russia that is still clawing its way back up from the economic collapse that occurred during the transition from communism to capitalism.

Perhaps if most of the country's wealth wasn't concentrated in the hands of a handful of corrupt oligarchs who live like a modern version of Roman emperors they'd be able to pay researchers a living wage.

Comment: Re:Ducted fans? (Score 1) 75

by Rei (#49763377) Attached to: The Hoverboard Flies Closer To Reality

You don't need "antigravity" (which in all likelihood is impossible). Diamagnetic hoverboards would be possible... if we could make ridiculously powerful, compact halbach arrays in the board. Also you'd need a clever mechanism to detect and deal with flying over ferromagnetic material, or otherwise it's going to smack into your board really hard.

"Well I don't see why I have to make one man miserable when I can make so many men happy." -- Ellyn Mustard, about marriage