Continuing in a space and science vein, let's reprise the topic
from last time... only this time with another of my rambunctious-uppity
videos.
Are
we ready, once again, to be a bold, dynamic people, ambitious and
confident, ready to take on new challenges and new horizons? See Our Reborn Future in Space,
my look at the ambitious proposal by Planetary Resources to mine
asteroids for "trillions" in purported mineral wealth. How are these
billionaires planning to obtain metals and fuel by mining nearby
asteroids? Has the future finally arrived?
Is it B.S. or not B.S.? In Part 2: Science or Fiction? I discuss the obstacles, technical and economic, facing Planetary Resources.
And while we're on the subject... see a brief but philosophical view of how crucial the next few human generations may be. Part of a series produced by the European Commission’s Horizons 2020 project.
== Is your brain worth the bother? ==
Is it B.S. or not B.S.? In Part 2: Science or Fiction? I discuss the obstacles, technical and economic, facing Planetary Resources.
And while we're on the subject... see a brief but philosophical view of how crucial the next few human generations may be. Part of a series produced by the European Commission’s Horizons 2020 project.
== Is your brain worth the bother? ==
The Brain Preservation Foundation is an interesting enterprise co-developed by John Smart (Acceleration Studies Foundation)
that's offering a prize for researchers who manage to preserve animal
brains in ways that would be suitable for humans and that keep intact
the web of physical connections - or the connectome - that some
believe to contain all of the information in both memory and thoughts.
Brain preservation aims at locking in these connections against
post-mortem decay.Yes, you've heard of Alcor which will contract to rush in the moment you are declared dead and perfuse your brain (or whole body) with chemicals so it can be cooled in liquid nitrogen. The contracts are expensive ($200,000 for whole body cryonics) and the promised event would be very gaudy. Still, it seemed the only option, for those whose aim (some might say fetish) was to have their physical organic brain itself someday brought back to life.
I appraise the tradeoffs in an article: Do we really want immortality?
Believers
in the connectome don't expect or need the organic brain to be revived,
so long as all the synapses and their weightings can be preserved and
later nano-traced in perfect detail. They hope memories, even
personality, might be emulated - some say "revived" - in a computer
setting. Now... I have some deep reservations about this "connectome" business, suspecting that there may be a lot more at work, possibly deep within the associated cells or in highly non-linear and ephemeral standing waves. Moreover, the semantic distinction between emulation and revival is one that we could argue about for decades... and will.
But let's run with this. Here's the innovative idea. If the connectome is everything, then preserve that. No need to revive the organo-colloidal brain, so plasticize it! Lock it in lucite. Store it at room temperature, on your kids' mantle or book shelf. No garish emergency room procedures or draining/perfusions around grieving relatives and no ongoing refrigeration fees. Heck, why not be decorative, till the nano-dissectors and hifalutin computers are ready...
Well, as I said, I have doubts at many levels. Still, it has advantages over the gaudy, rather chilling image of cryo skull-dipping. To become a knick-knack. A conversational tchotchke on my descendants' shelf... and at much lower price, with a lot less drama or dependence on fickle contracts? Well, it grows more... hm... the word isn't "tempting." But let me put it to you.
What level would the price need to reach before you shrugged and said: sure, sign me up?
==More on the flexible Human Mind==
Using
brain-imaging technology for the first time with people experiencing
mathematics anxiety, University of Chicago scientists have gained new
insights into how some students are able to overcome their fears and succeed in math. Teaching
students to control their emotions prior to doing math may be the best
way to overcome the math difficulties that often go along with math
anxiety. READ THIS.Much discussed at the "Transhumanism" talks at TedX DelMar where I spoke about space in our neo-human future... brain-computer interfaces, which are starting to mature.... or IMmature! See for example Brainball! a special table uses magnets to move a ball AWAY from you the more RELAXED you are. (You wear a brain wave monitor.) I love the image of the two competitors, each looking more unconscious or dead than the other!
And... a Real ‘Beautiful Mind’: College Dropout Became Mathematical Genius After Mugging.
== Astronomical News ==
British scientists have produced a colossal picture of our Milky Way Galaxy that
reveals the detail of a billion stars, BBC News reports. "When it was
first produced, I played with it for hours; it's just stunning,"The Pioneer Anomaly has been resolved, thanks in part to efforts of the Planetary Society to help a small team find, then translate, and finally analyze more than 30 years worth of data, recorded on archaic media. Sorry, it wasn’t “strange physics.” But some very good science sleuthing was required.
Astronomers are reporting the first "Earth-sized" planets orbiting within the habitable zones of their stars. They report stellar parameters for late-K and M-type planet-candidate host stars announced by the Kepler Mission. Three of the planet-candidates are terrestrial sized with orbital semimajor axes that lie within the habitable zones of their host stars. Note with this kind of star, there is the chance of getting tidal locked, with one face always toward the sun.
It's difficult to knock a star out of the galaxy. To give a star the two-million-plus mile-per-hour kick it involves tangling with the supermassive black hole at the galaxy's core. Astronomers have found 16 "hypervelocity" stars traveling fast enough to eventually escape galaxy's gravitational grasp. Now, Vanderbilt astronomers report in a recent issue of the Astronomical Journal that they have identified a group of more than 675 stars on the outskirts of the Milky Way that they argue are hyper-velocity stars that have been ejected from the galactic core.
Wind At Sea Is Strangely Van Goghish,
says NASA. New instruments have taken a leap. One of the most beautiful
and surprising things I have ever seen! For the first time we can see
how similar our atmosphere behaves to that of Jupiter. Stunning,
beautiful and thought-provoking!Pop-Art? Artistic geological maps of solar system bodies.
==On the Technological Front==
One of the most instantly recognizable features of glass is the way it reflects light. But a new way of creating surface textures on glass, developed by researchers at MIT, virtually eliminates reflections, producing glass that is almost unrecognizable because of its absence of glare — and whose surface causes water droplets to bounce right off, like tiny rubber balls.
Touché proposes a novel Swept Frequency Capacitive Sensing technique that can not only detect a touch event, but also recognize complex configurations of the human hands and body. Tap your arm or hand for gesture commands without a lens or electrodes, and so on.
== And some lighter stuff ==
See a hilarious xkcd about picking a college major: Why 'Undecided' may be the best choice.
A lovely fantasy Voyager cartoon.
Another beautiful mash-up of classical music and space imagery. Inspiring... and a bit cautionary....
Know that reader who loves to mix both romance and adventure with unusual personalities... and a little science? Have them give a look at the newest novel by Lou Aronica (author of BLUE) and Julian Iragorri: Differential Equations. I see another book with that same title on my shelf, nearby (among my mathematics textbooks!). Lou’s writing is much less dry... and there’s more romance!And finally.... faux vintage travel posters for the solar system.
91 comments:
Plastination is not a bad idea: http://www.gwern.net/plastination
But the concern is whether you can plastinate thoroughly quickly enough. With cryonics, even if you perfuse poorly, you still are guaranteed everything will either vitrify or freeze; with plastination, bubbles of flesh might just rot. That's why existing procedures soak the brain for weeks, so diffusion can penetrate the entire brain - but obviously that's no good for high fidelity preservation!
(You also wouldn't want to leave a plastinated brain out at room temperature, since you will still be losing lots of information over decades. Ideal would be a hybrid - the brain is plastinated and then cooled. If the cryonics org breaks down temporarily, rewarming is not an instant disaster as long as it's not more than few months/years.)
The problem with having a thousand years worth of REEs is that there won't be an immediate market for about 990 years worth of them.
So even allowing for expanding demand due to both economic expansion and lower prices, a financier is going to look at that stockpile and see a revenue flow equivalent to, say, double the current market per year - less storage costs on the other 900+ years worth.
(We used to have similar discussions within the Queensalnd EPA on how to calculate the value of our coal resources - about 800 years worth at current extaction rates. A simple multiplication of the tonnage by the market price produces figures well in excess of current world GDP while applying standard economic principles to derive a Net Present Value for the derived cashflow produced unreasonably small figures.)
On a different note: I love your comments about exponential curves and S-curves and how assuming either the plateaus or the steep inclines is a valid map for the long term is invalid. You explicitly made that point abotu economic bubbles. I wish more peopel understood that the same applies to economic busts.
The imminent demise of the capitalist system has been predicted about every decade since the 19th century.
It jas never eventuated - which means that for those of us unhappy with elements of the current capitalists system, simply waiting for the system to collapse isn't a realistic option.
1) I had a snarky answer for locumranch about Einstein and meritocracy... plus thanks for SteveO and others for great meteorite metal comments, at the end of last comments section. But bring it back here.
2) Plasticization should aim for the marvelous effects on insects and plant cells one sees in 45 million year old amber. Of course, at the molecular level...
3) Ian I believe you under-rate how many orders of magnitude of increased demand would ensue, if prices dropped by orders of manitude. The tip of the Washington monument was made of the most epensive material of its day... aluminum. Which no one could figure out how to refine. Its copious availability now is matched by its incredible demand and use.
This should throw some fat on the fire, so to speak:
Possible link between maternal obesity and low childhood intelligence
Dr. Brin,
You would know better than I: is there even a postulated mechanism on a non-differentiated asteroid that would concentrate elements into an ore? I know of one to concentrate a volatile like water (e.g. the mechanism for possible water at the lunar pole) but most enrichment Earth-side is hydro- or gravity-related one way or the other. There are not very many igneous ores for that matter either. Some primary metal, diamonds, but nothing you can count on commercially. I am not even sure low-g magma would differentiate that way anyway.
Even hand-waving the whole long discussion about economics, if you bring me back a big orbiting chunk of regolith/basalt, I am going to have a hard time getting anything useful from it. Even if it is relatively enriched in platinum series, if I have to mine 10000 tons of regolith to get an ounce of iridium, it ain't a' gonna' happen,at least until we really need iridium and I can't get it anywhere else.
If you somehow bring me a big chunk of Ni-Fe asteroid, we could probably eventually find a way to make something useful from it as long as it stayed in space. It wouldn't make any sense to bring down to Earth, as steel is cheaper than dirt, and a lot more useful than Ni-Fe. (I am doubting you could make steel with current tech in space from it, at least at large-scale.)
And TANSTAAFL - dropping a big pot o' gold down with a regolith ablative shield is still going to put the same amount of heat into the atmosphere as dropping a big golden rock would. It just spreads it around more. Drop it from the asteroid belt and, well, it doesn't matter what you coat it with, it is going to be bad for everyone to try to absorb that amount of kinetic energy. You could slingshot-style brake it to use up that kinetic energy, I suppose. You would still have a bloody large amount of heat.
Hmm, think a mined-out future Australia would send up a mission to drop a big metal asteroid out in the middle of the outback to start a new mining rush?
I looked - there is not one mining or metallurgical engineer listed over at Planetary Resources. That tells me something, and it smacks of unexamined premises...CITOKATE
The problem David is that our hypothetical merchant banker doesn;t care about the volume of metal you sell per year, he cares about the revenue generated.
From memory, Platinum sells for around $45,000 a kilogram at the moment
I'm sure you could sell a lot more of it at $1 a kilgram. But could you sell 45,000 times as much?
To chime back in on off planet alloy making; iron + nickel + chrome + a little bit of other elements= some of the most common superalloys (Inconnel family). Best practice earth side is to pour through a filter system while under vacuum. Substitute out the iron for cobalt and you have other, also prevalent, superalloys.
The saturn V booster used inconnel X750 for the thrust chamber in the engine. But my bet for alloy most likely to be first mass produced out of spaceborn materials is Inconnel 718. It is more easily weldable than other superalloys.
Wow... I got some super smartypants members of the blogmunity! I had suspected an iconel alloy might be analogous to what you could get by blowing carbon thru Ni-Fe melts. If you can get any kind of real steel in large throughput in space, then you've opened up big doors, out there.
I am not sure you could not use the descending gold bars in a tether-transfer system to use sap off the downward potential energy of the gold and give it to outward-bound cargoes.
Indeed, a need to spend mass and energy that way might make us SUBSIDIZE outward cargoes, just to get the gold n'such without overheating the atmosphere! Spew bunches of stuff out toward Phobos just to get the gold... and colonists later use the stuff.
Ian I think platinum is exactly an analogue to aluminum when they used that "rarest of all metals" to cap the Washington Monument as a gesture of pride. Aluminum is probably roughly 5 order of magnitude less expensive now... and 6 or 7 order more used than back then.
====
Oh, about that article: Possible link between maternal obesity and low childhood intelligence.
http://researchnews.osu.edu/archive/maternobesity.htm
Gee wiz... will we ever see a single datum suggesting that the denizens of Red America, who proclaim so loudly that they know better how to live and raise kids, are ever right at all, even once? About anything whatsoever?
Has anyone found a site that sells union soldier Kepi hats for adults (not cheap kids costumes) at reasonable price? I'd love to start spreading that meme.
Oh! You guys are the first to be told!!!
My web site http://www.davidbrin.com has had a total facelift. More a total rebuild! top to bottom. Comments welcome.
My high school chemistry teacher has a background in animal training (among other things). A couple of times during the year, a student would start freaking out because they didn't understand something. In these cases, the teacher would calm the student down before explaining the topic again.
Later, I asked him if he did this because he was an animal trainer. He said yes, that "fear has to be removed before learning can occur". I wish more teachers understood that! Nice to have research backing it up.
Doug,
Re: Meteor metal knives.
That is way cool.
Re: Vapour separation.
Can't remember where I read it, but I recall an idea to use vapour depositing of aluminium to coat inflatable structures, initially to make fuel tanks but eventually large bubble habitats. The bad news is it only works in a vacuum chamber. The goods news is...
SteveO,
Re: Lunacrete cinderblocks.
"but nobody on Earth is going to pay for rego-bricks."
Them damn groundhogs, all'a time rippin' off honest spacefolk.
The lunar ISRU guys are looking at it for NASA, to reduce the cost of a future manned lunar base (as in the Vision for Space Exploration program, before it got hijacked by Constellation (and now SLS.)) Using the blocks as shielding/insulation/thermal-mass for inflatable surface-habs, and better landing pads. Using the meteoric-iron (in the regolith) for simple structures like antenna towers, dish supports, etc. They even think they are able to make things like vehicle chassis, bulldozer buckets, etc, even further reducing the mass you need to carry from Earth, further reducing cost, but I think that level of engineering is too risky for a first-gen NASA program.
It's a "market" in that the US might one day fund a lunar base, and these tools/techniques might make it more affordable or effective. It's not a "market" in the sense that the base itself it for-profit. (Likewise, Planetary Resources' early customers will mostly be not-for-profit science missions.) I don't see that as contradictory. Plenty of governments have funded exploration in the past, even if they buy a ship from a regular commercial ship-builder.
Re: Carbon.
What would be the best source of carbon from asteroids. I mean long-term, projecting ahead 50-100 years and assuming a bunch of fully developed specialising industries in space, trading between each other as well as selling to customers, where would you source "industrial" carbon? Carbon-minerals from rocky asteroids? Hydrocarbons from wet or icy asteroids/comet-remnants? Buy waste from the tourist habs? Or something else. We're kind of spoilt for choice in easily purified carbon on Earth, thanks to biology and its legacy.
Re: Back to the bricks.
I've always liked the image of an astronaut in EVA suit on the lunar surface, hunched over an anvil next to a primitive solar forge, hammering out a new pick-head or something.
Locumranch,
"That Einstein was a genius, this is indisputable, confirmed by 20/20 hindsight.
Not by hindsight. That was my point, even as a ten year old he was recognised as something special. Likewise as a 16 year old, when applying directly to one of Europe's best science Universities, even when he failed some of the entry exams, the principle himself recognised Einstein's brilliance and recommended a prestigious Swiss highschool for Einstein to finish his studies, then accepted him straight back in. Recognition didn't happen in hindsight in the 1930's, it happened then.
The two examples of him not being recognised - the crumby 19th century German highschool and the "dry spell" when he couldn't find a teaching position before getting his doctorate - have been inflated to epic significance by people who want to imagine there's some kind of philosophical lesson, "See, even Einstein was a highschool drop-out/struggled for recognition". But it's bullshit. Einstein never struggled for recognition.
"That his theories were universally accepted & acclaimed from the moment of their creation, this is yet another myth,"
Nothing is "universally accepted & acclaimed from the moment of their creation" in science. There is no such "myth". Science doesn't, and shouldn't, work like that. Anything important needs to be tested. The more important, the harder the challenge. As David likes to say, Criticism Is The Only Known Antidote To Error.
David,
Re: From the videos. Carbonaceous chondrites.
Did your work suggest that all carbonaceous chondrite meteorites came from comet remnants (sans volatiles)? One particular subtype?
Re: Bagging and slagging comet-remnants.
If you cooked a comet-remnant, wouldn't you risk explosive expansion of the volatiles ripping the asteroid apart, shredding the bag? Ie, wouldn't you have to break up the asteroid into icy rubble to ensure it melted/vaporised in a controlled way?
Re: Using the momentum exchange tethers and incoming gold to propel cargo outwards.
Be funny if the energy was more valuable than the gold. The gold was a near-worthless waste product dropped to Earth after they were done with it. Gold-pressed momentum.
Question for David: would it be practical to use a magnetic or electric field to capture charged particles from the tail of a comet?
Going further, soem fraction of those ions would be metallic, would it be possible to use a mass spectrometer to separate the metals from the volatiles?
Yes, I know that on Earth the tail would likely be considered a pretty good vaccuum but the magnetic scoop wouldn't need to be particularly massive (and I'm sure there a bunch of papers out there about designs for Bussard ram scoops)
Another odd little idea: rather than shipping volatiles up to orbit from the surface of the Earth or from asteroids, has anyone considered using an orbital ramscop to harvest material from the upper atmosphere?
There's lots of fiction about mining gas giants for Hydrogren, why not mine the stratospehre for Oxygen and water?
(You'd need some sort of ion or nuclear drive so that you didn't end up using up more volatiles than you recovered.)
Oh and this should please you David: Blue Seed the proposed floating business incubator is making progress.
Mind you its a long way from "expressions of interest" to lessees puttign down money and I think thiel is beign unrealaistic in suggesting he'll luanch by Q4 2012 when he still doesn't even have a ship.
Forgot the link:
https://news.google.com.au/news/url?sa=t&ct2=us%2F0_0_s_14_0_t&usg=AFQjCNHjC5hD-neyr4ShXgn_rDglXRAf_w&did=7a7c9ca6d286f9b5&sig2=YV1dkNdmxbP07-cwefJkPw&cid=17594032695451&ei=4w-tT6DjE8fvlAWa5gE&rt=STORY&vm=STANDARD&url=http%3A%2F%2Fwww.technology-digital.com%2Fweb20%2Fblueseed--silicon-valley-on-ship
Curious about your thoughts on this David: Saudi Arabia is planning to invest massively in non-fossil energy.
http://www.pv-magazine.com/news/details/beitrag/saudi-arabia-targets-41-gw-of-solar-by-2032_100006719/#axzz1uSl2b03a
Fun stuff - metallurgy for the win!
I worked for ALCOA for five years as a metallurgical engineer. Let's just say I don't think that platinum is the new aluminum...
Fundamentally, space miners are skipping the part where they actually mine the rock, assuming that an asteroid is like a chunk of Earth, with non-homogeneity including ores. Just because something is there, even in higher average parts per million, does not mean you can mine it without ore concentrations. A mine-able ore *is* a concentration of some element, and that is why we don't mine aluminum (3rd most abundant element on Earth) any old place. (Well that and it is really dang difficult to separate - we need hydro-geological processes to form bauxite to make it.) As far as I know, with the exception of the big planetesimals or pieces from them, asteroids are undifferentiated and fairly homogenous.
Al is a light element, so same volume much less mass (and we still have to move mass around in space). It also has the ability to solution heat treat (e.g. the 6XXX series alloys) as well as work harden (e.g. the 2XXX series). It also has a good modulus ("springyness") but shape can make it stiff, and it dissipates energy better than steel in a collision. It does not get brittle when it gets cold, even cryogenic cold. (It is used to make the giant LNG containers - most other metals would shatter. Steel shatters even at terrestrial temperatures up on the North Slope.)
Oddly, I can't find any information on using Pt as a building material. I did find that it work hardens, which is kind of surprising to me. I would have assumed all those guys would be more like gold. I found a few phase diagrams but they are for jewelry so Pt-Rb, or Pt-Au.
Platinum is very useful as a catalyst, and it is pretty, but I don't see it going the way of aluminum, unless it has undiscovered properties.
Re: steel
To make steel in space you need iron (if you have a very rare metal asteroid, no prob) carbon (if you have a very rare chondrite, no prob), lots of oxygen (uh-oh), lots of limestone (formed by oceans, uh-oh), and of course your alloying elements (let's say that those are present in your metal asteroid).
At least, that is the conventional process. There could be some other way, of course.
"SteveO said...
You would know better than I: is there even a postulated mechanism on a non-differentiated asteroid that would concentrate elements into an ore?"
Well, there's always time and gravity.
We know from the prevalent Widmanstätten patterns in meteors that they spent a long, long time cooling and forming those enormous crystals, thousands to millions of years, during which time presumably the denser elements would have congregated near the center of an asteroid, and the lighter elements formed a crust -- but this would only apply to the larger asteroids, ones which have fused into a solid spheroid while hot and liquid enough to allow for migration and separation of the interior molten material.
We even see this on Earth -- we have a solid iron/nickel core, loaded with enough dense radioactive elements to generate the heat that keeps the middle layers molten. We also have the Sudbury Basin, an ancient impact crater large enough whose ore deposits, according to one theory I read, are due to the gravitational separation of the resulting magma, though I cannot find such a claim on a casual search.
A federal judge has ruled that a final volume of the CIA's three-decade-old history on the failed Bay of Pigs invasion of Cuba can remain shrouded in secrecy because it is a draft, not a finished product.
Re: Inconel
The properties that make Inconel cool are mostly not needed for "generic" space construction. Not a deal breaker, just don't get enamored of "superalloys" if you don't need 'em (or consider alternative recipes that would never work in an Earth environment). In this case, it might just be more convenient to make them due to raw material availability in space. I understand they are quite difficult to machine.
I don't know the fab process for it so I can't speak to its space-factuability - I am guessing though that the vacuum step is either used for degassing or for the pressure difference to force it through. If the first, you won't have that problem if you fab in vacuum. If the second, you would need to sacrifice volatiles.
Also remember, as I alluded to above, while metal meteorites are more common on Earth, that is due to their ability to survive entry and impact. They are quite rare as meteors.
Doug,
Metal meteorites are a special case - they must have formed in a planetesimal large enough to differentiate. You are looking at the former core of a body when you are looking at a metal meteor.
I am asking about all those other asteriods that Planetary Resources say they are going to be mining. The ones that have very minimal gravity.
Dr Brin, since you like to link to the xkcd comics website, I noticed this one:
http://xkcd.com/1047/
which is a chart of a whole bunch of mathematical approximations, such as 99 to the 8th power as the approximate number of meters in a light-year.
Yet there is one approximation I find fascinating, and as far as I know, I'm the only person who has noticed this (until now). Even though there is no particular reason there would be a relationship between the two--the ratio of a kilometer to a mile is very close to the golden ratio.
That is: a kilometer is very nearly .618 miles, and a mile is very nearly 1.618 kilometers.
Larryhart that's interesting!
SteveO great metallurgy!
Jane S - nice story about your teacher.
Paul - I never said most CC types were extinct comets. In fact, those would be mostly large bodies.
Ian - gold pressed momentum.... ouch! But what a concept
Ian - the magnetic ion tail of a comet is very diffuse and immense. And dangerous. Sudden currents.
- Your atmosphere upper scraper is proposed at NIAC!
"Curious about your thoughts on this David: Saudi Arabia is planning to invest massively in non-fossil energy."
-I have said repeatedly. The sons of ibn Saud are very very smart and determined.
A man made a wedding ring from a meteorite. Included are links for pictures of the ring and Widmanstätten patterns.
http://news.yahoo.com/blogs/technology-blog/man-forges-own-precious-wedding-ring-meteorite-032635030.html
A number of meteorites have had their parent bodies tagged, or at least strongly suspected. If you know that meteorites with 'X' characteristic are likely sourced from this group of asteroids, that narrows down the search field significantly. Planetary Resources doesn't have to go after a huge chunk, since asteroids with common characteristics often travel in 'families' of varied sized pieces, all in about the same orbit. Just find an appropriately sized bit for your project. Isn't PR also using those proposed cheap orbital telescopes to look for good prospects (no pun intended)?
TheMadLibrarian
hikeya heejun: Samurai exclamation of surprise
Mad, and some of those families are known to follow reliable Earth-grazing orbital paths.
Cases in point: the Perseid and Leonid meteor storms.
Usually meteor 'storms' are cometary debris bands, leftovers from a comet as it orbits and Earth just happens to pass through a particularly thick ring of leftovers. Unfortunately, although there might be some bigger chunks in along the way, most of those remnants are marble or smaller size. You'd do better to figure out a way of Hoovering up orbital rubbish, than to try to collect those cometary trash streams.
TheMadLibrarian
fresolo biasinp: cheese making mold
SteveO,
Re: Platinum uses.
1700C melting point... How would it go as a reentry-shield? I do likes me spaceships bling.
Re: Cold brittleness of steel (or iron).
Forgot about that. Got all excited about the low thermal expansion of Fe-Ni alloys and forgot about actual brittleness. That could be the show-stopper for eventual adoption of meteoric nickel-iron for even basic structures. We may need those weird zero-g impossible-alloys that we're all secretly hoping for.
(eoomp seryp: First catch your Eoomp... - http://www.wikihow.com/make-eoomp-seryp)
Paul, you mention buying waste from space tourist habitats.
A quick look aroudn the interent suggests the average human excredtes around 1.5 litres of urine and 0.5 kilograms of feces per day.
For any extended stay in space you can also figure several litres (very conservatively) for washing, cooking and waste disposal.
Bigalow, Virgin, Astrium et al seem initially to be planning to send up 7-8 people for a week at a team.
8 people on average over a year would produce around 14 tonnes of urine and waste water and 1.4 tonnes of feces.
Once youve got the stuff up there you might as well use it (if only as shielding) since the launch cost works out to around $30 million.
Of course, not being stupidm the tourism companies will probably be working on recycling the water at least. So the net contribution per person is more likely to be closer ot the daily average.
Still, if we end up with hundreds or thousands of torusists, it still amounts to tonnes and tonnes of volatiles.
Ian, a clever independent space bartender could sell beer and with the right timing collect more H2O than he dispenses in the beer.
On the brittleness of the type of simple nickel-iron alloys that would be most plentiful given the right asteroid, exactly how cold is space in Earth's Goldilocks zone? Out of Earth's shadow (or the moon's). That is, more meaningful, what would be the resting temperature of an 8" I-beam, polished, in the normal sun, in the vacuum of space? There are limits, the upper being a full-on sideways exposure of an infinitely long beam, and the other an end-on exposure of an infinitely long beam. I think. And in the real world, heat variations in a 100' I-beam slowly rotating from end-on solar exposure to full-on (sideward).
Don't make me invent carbon-fiber reinforced asteroidal nickel-iron composite beams! Because I'll do it!
(ionspork tobany)
I really enjoyed the two videos. I would be interested in donating computational power from my multiple PC's for Planetary Resources or whomever needs the data to make this succeed. Please keep up updated on this aspect.
Just one little way the little person can help make this a reality.
Anonymous:check out Boinc. It lets you donate your spare processor time to all sorts of worth purpsoes from SETI to drug design to developing open source translation programs.
I'm sure the asteroid miners will take advantage of it in time.
Re. ni-fe brittleness. I naively occurs to me that your average knocked about ni-fe asteroid isn't. Is that correct and could this be made advantage of?
Nice Existence promotional video by Patrick Farley btw. Just like the monolith from 2001, only rounder!
See the teaser now in the upper right corner of Contrary Brin... but watch at hi res! It's better that way.
Then watch the whole Trailer Monday night!
d
Author Rips Bad News
http://www.cracked.com/blog/5-ways-to-spot-b.s.-political-story-in-under-10-seconds
Since we're on a space jag, anyone have any thoughts on what the USAF's X-37B is doing during those year-long top-secret missions?
I have a bunch of HELP QUESTIONS for you brilliant fellows.
1) I hope you like my NEWLY RE-DONE WEB SITE! http://www.davidbrin.com
2) Does anyone know how to set up some of my sub-pages so they can have simpler URLs and not need".html" or ".htm" at the end?
3) See http://bookscreening.com/frequently-asked-questions/
Does anyone know of any other aggregator sites that collect and help people see book trailers?
Correction... Patrick Farley's preview-trailer for EXISTENCE won't be viewable till Thursday or so. But spread the word about the entirely different teaser!
www.youtu.be/ANVT0hYbAfE
Thanks all.
db
2. It's possible, but usually gets handled by the underlying engine (Whatever handles http://www.davidbrin.com/ needs to do the interpreting of the rest... scuse the pun!). If you're just using raw html with page based links, then no. Something like Ruby on Rails? Certainly, but you need to set up the data mapping and complexity leads to fragility. You might be able to get Apache to do something, but I'm no expert there!
It's simpler than that.
Call your files "index.html" and site them inside directories. So,
http://www.davidbrin.com/existence.html
becomes
http://www.davidbrin.com/existence/index.html
which can always be reached by the URL
http://www.davidbrin.com/existence
That what you're looking for?
It's simpler even than that. Your web site is running on the Apache server, which is flexible in mapping URLs to file names. Here's a good place for your webmaster to start: http://httpd.apache.org/docs/2.0/content-negotiation.html You just have to turn the setting on.
And a piece of advice for webmasters who are reorganizing sites. Forward this to yours and remind him not to break your old URLs.
Cool URLs Don't Change
Dr. Brin,
Saw the teaser trailer - it looks like a good romp, but then I was gonna read it anyway, so I am not your target audience! (Still worried about Streaker and Jijo though...)
All,
I love reading blog comments where the term "Widmanstätten" is bandied about. :)
Jumper,
There is no "cold" or "hot" in vacuum, not in any useful way. Temperature is a measurement of atomic motion. No atoms, no temperature. That said, things (atoms in the I-beams) get broiling hot in the sun since there is no conductive or convective cooling - only slow radiative. Eventually, something would radiate to match the CBR temperature. That is why the Moon itself is so cold, though obviously not 2.7K. Thermal cycling is a strong design consideration on orbit. I have some students at Ball Aerospace and Lockheed-Martin - once you invent your composite I'll put you in touch. ;-)
Paul 451,
Pure Pt wouldn't be good for a heat shield, as I understand them. You don't want a refractory (high melting temp) material so much as one that transports heat away from where the people are, or insulates them from it. You can do this via ablation, like the Mercury, Apollo and now the Orion, or via low thermal conductivity, like the Shuttle. If we think about using it to conduct heat, there are better conductors that are a lot less dense. Weight is the enemy. No idea bout Pt compounds, but they would still be dense. Wikipedia says the oxides decompose on heating, so that would be bad.
Tony,
If a metal asteroid gets smacked by something really big, the energy is enormous and the metal would act (and in moments be) liquid. And too, where do you think we get all our neat metal meteorites? Bits smashed off of metal asteroids by smaller projectiles.
Also found more reports of how even the "metal" asteroids are mostly really just metal-rich homogenous, undifferentiated bodies. e.g. 433 Eros Imagine an ore orders of magnitude lower than anything commercially viable on Earth.
Even (6178) 1986, the richest asteroid known, has something like 0.013 troy ounces of gold per ton on average, well below ~1 oz.ton concentration in commercial Earth ore. (I estimated from the Wiki article.) Still, there may be heat differentiation there, so there may be ore concentrations somewhere.
Notably, one of the guys on the board of Planetary Resources wrote a book where he proposed 3554 Amun as a place to mine. Too bad it has turned out to be not consistent with being metal type.
Man, why am I the nay-saying nabob on this? I *want* asteroid mining!
Great stuff guys, thanks.
SteveO... you are the naysaying nabob because you are "contrary"!!!
It's how guys like us got burnt alive in other culture... but can be valuable in this one. ;-)
Early asteroid mining techniques would likely just use large solar concentrating mirrors to directly vaporize spots on asteroids, with the vapor deposited nearby through electrostatic attraction, partially sorting the material by mass.
The material with higher concentrations of the desired elements then becomes "ore" that could be gathered and processed again for greater enrichment.
Fractional distillation might also be an option - heat in stages to boil off and collect different materials at different temperatures.
I doubt we'll see centrifuges used early on to induce material separation - the forces and temperatures involved seem to imply fairly massive constructs - and early mining efforts will be all about minimizing the mass delivered to the asteroid.
Tom,
Interesting idea. Let me think "out loud" here.
1) we build a ginormous mirror array out of...what? I guess we could reuse our solar sails here, something like mylar, but we will need a superstructure and an anchor (otherwise, off it goes!). It will need some stiffness, or maybe rotation would serve, to be effective at focusing sunlight in a small spot. That seems like a non-trivial engineering problem. We could build gigantic metal mirrors, but chicken and egg there.
2) Let's say we figure that out and we vaporize a bunch of rock. In atmosphere and gravity, we get local deposition if we heat up a metal or metal oxide, sure, due to atmosphere slowing it down and cooling it off. What about in space? You are kicking off atoms well past escape velocity, so we need some sort of attraction. Electrostatic - hmm, well we are interested in metals - are we thinking we have ions? Because then we need to be making plasma, not just hot rocks or gaseous metals, and I don't think that is going to happen with solar concentration. I'm have no idea if volatilized metals are going to have a charge. Maybe from friction during the process? Here on Earth, metal volatilization is often done on compounds, like oxides or chlorides, which we probably won't have in space. Those are condensed when they hit something relatively cool. We could use an effect like eddy currents to deflect, say, aluminum, but you are going to lose a lot to space that way. Good luck volitilizing Pt and Au and all that. It is easier in vacuum, no doubt, so that is working in your favor.
I am trying to get a picture of how this would work and am not seeing it. Is there a design out there that you can point me to? There are just so many things we naturally assume will work like on Earth that wouldn't, so I am having a hard time seeing it. Too many variables I don't know about, so I am not going to invest my $1 yet. ;-)
SteveO -
I was thinking in terms of induced dipole effect. Might not work for individual elemental atoms, but without surface tension or gravity to hold material in place, I suspect much of the matter blown off will be clusters of atoms anyhow.
SteveO:
Also, the mirrors need not be all THAT big - we're not trying to vaporize the whole asteroid, just a small spot at a time, from a fair distance away.
To minimize polluting the mirror surface, it needs to be a fair ways off - so only a small curvature. The stiffness of the material plus a springy rim to keep it stretched should be adequate.
Aiming/changing the focal length of a flimsy mirror might be an issue though, so it might be best to build in a mesh that can be slightly tightened with an embedded piezoelectric effect to alter the curvature.
Anchoring it is a bit of an issue - the asteroid will likely be tumbling, so you can't simply tie it up. If possible, one would balance the slight solar pressure with the slight gravity of the asteroid, creating a statite. If not, there's plenty of reaction mass to use in a drone to tug it back into position periodically.
Looks like blogger didn't like my other post - too big? Re-try in two parts:
Planetary Resources should consider setting up and spinning off "First Orbital Bank", a momentum / potential energy banking concern.
A subsidiary - Transfer Services Inc - would handle orbital operations, bagging space junk and transferring it to safe "vault" orbits using high efficiency ion or plasma engines or electromagnetic tether drives. This captures valuable abandoned potential energy and momentum, and adds to it, instead of wastefully de-orbiting and destroying it. Tough, space-durable fabric containers would help protect First Orbital from collision liability issues. This part of the business has the side benefits of providing experience with safely containing and moving lumpy and sometimes loose materials, and with high efficiency thrust systems -both may be useful for eventual asteroid mining ventures. First Orbital might also obtain space junk clean-up fees from insurers of satellites.
Transfer Services would also develop tethered momentum transfer systems that will make First Orbital energy assets “liquid”. Customers will be able to borrow, purchase or withdraw momentum from the First Orbital vault, and pay Transfer Services to add it to orbital investments such as geosynchronous satellites. Transfer Services’ profits would also add to First Orbital’s assets on deposit. Planetary Resources’ asteroid survey drones would eventually be First Orbital and Transfer Services customers.
When other space-based businesses realize the value of the energy in their existing and new satellites, last stage rockets and other equipment, and decline to simply abandon them, Transfer Services can offer to help them make deposits with First Orbital. As an exchange rate becomes established through momentum purchases, the value of First Orbital’s assets will become widely recognized, allowing it to obtain and make loans in conventional currencies against its unconventional momentum assets. Eventually that could include loans of operating capital to asteroid mining ventures like Planetary Resources, secured by drone-proven asteroid mining claims or rights (once the legalities of the latter get worked out). Even a highly conservative loan to asset ratio will substantially multiply First Orbital's financial power.
First Orbital Part 2:
As the First Orbital vault fills up with "junk" launched from Earth, the relative value of momentum will fall. So it will be critical for First Orbital growth, to keep moving into other areas of space finance. A space junk recycling enterprise might extract small amounts of gold other precious metals from defunct satellites, creating the first small deposits of precious metals into First Orbital’s vault, to diversify its asset base. Compacting space junk would also make it easier to use for momentum transfer. Automation and processing technologies involved in recycling should be useful for automated mining operations.
First Orbital will become “the most secure precious metal depository on or off the planet. Why send your space gold to Earth, where common robbers can break in? Keep it safely on deposit in orbit for a small yearly fee, and borrow against it on Earth!” Inexpensive methods of transferring precious metals to banks on Earth will eventually be necessary, but early on First Orbital could absorb the cost of small transfers to demonstrate the capability to produce precious metals on demand from Earth-bound depositories. As soon as space law is reformed to clarify mined materials as property, and asteroid mining gets underway, First Orbital can simply store much of the mined precious metals as deposits – no need to immediately transfer it to Earth to borrow against it or even sell it to investors willing to keep it deposited with First Orbital.
Oh, and Tom, I'd like to see how fractional distillation would work in low/micro g...there are ways around it that I was able to find, but nothing so far that would work with metals.
Tom - did you see the video of the solar sail Japan launched? I don't think you are going to be able to rely on a thin film mirror. Of course, I could be wrong!
A momentum bank - literally! I love it.
So we add energy to existing junk in order to boost it to a higher orbit. People pay us money for cleaning up the neighborhood. How do we withdraw the energy? If I take any of that momentum out that means it goes back to a lower orbit. I don't think those satellite owners are going to like that. I might be missing something here.
Hmm...still I like the idea of a momentum bank. How about this: You could de-orbit the space junk - steal its momentum - and put that in the mo-bank.
Momentum as a fungible. Mo-dollars? The exchange market would be fascinating.
Good grouch-crit from SteveO! And Tom C I love First Orbital. But you need to parse FAST orbital transfer...which would be either by tether sling (TS) or rocket... versus slow transfer which can be by electrodynamic tether. The latter can re-stock the momentum holding pens for the former.
But dig it. When asteroid mining begins in earnest, you'll have a flow of valuable stuff downward that needs to be de-orbited gently and upward stuff that could use the momentum in exchange. That's the economy we worked out earlier and the coolest thing so far.
QUESTION! Let's brainstorm whether space ores can be heated and separated by the energy or atmospheric entry! Picture a glob of the stuff inside an aeroshell that cools itself by transmitting heat inward to the ore-cargo, while using its shape to maximize the time it takes to fall from orbit to target point on the surface. Also, it maneuvers to maximize separation forces on the molten matter within. Ballpark possible?
"How do we withdraw the energy?"
Several ways
- a tether extending down from a a higher orbit will transfer momentum to objects in a lower orbit.
- once serious asteroid mining gets under way, you'll need ways to decelerate incoming objects to allow them to be captured into Earth orbit
Another possibility I find encouraging is, once again, a gun or catapult mechanism that impacts a pusher plate on a spacecraft or satellite. The nice thing there is if you can get sufficient accuracy you can use almost anything for the reaction mass.
One potential way to use asteroid regolith would be selective laser sintering.
http://en.wikipedia.org/wiki/Selective_laser_sintering
This would potentially allow astronauts on the ISS or a future replacement to make components using regolith or a mixture of regolith and a monomer.
There's also no real limit I can see to scaling this up - especially not if you can use concentrated solar light in place of the lasers. Concentrated Solar Thermal Plants here on Earth regularly get up to 1,000 x concentration.
A further thought: it isn't necessary to produce the final purified metal in orbit, a concentrate that's higher grade than terrestrial ores and that can be delivered anywhere on the planet for minimal cost will do nicely for the more valuable minerals.
So, I'm thinking big, lifting bodies made of 50% PMG concentrate laser-sintered into a metallic glass and shaped into a flying wing. You use a tether to lower the flying wing into an unstable orbit where it's decelerated further by the upper atmosphere.
The flying wing would be equipped with a terminal guidance system like the ones used on the JDAM munitions.
http://en.wikipedia.org
/wiki/JDAM#JDAM_Extended_Range
These should allow it to be steered to within a few square miles on the ground and decelerated to a touchdown speed of a few hundred KPH.
(The big problem with this approach would quite possibly be popular opposition to having large rocks dropped on the Earth. Fortunately, I happen to know a country that has lots and lots of empty space and quite lot of mineral processing experience.)
Work things right and you could use the heat or re-entry as part of the processing - burn off impurities as you go.
Just got this from my pal, the world's tether expert:
There are several tether schemes that could pay for lifting stuff out of earth's gravity well by dropping other stuff down into it. This can be done by space elevator or slings. But the 3-D orbit mechanics are tricky. The fact that we imagine and draw stuff on a page doesn't mean that all orbit planes are coplanar.
Heating by reentry is tricky: for large objects, there isn't time to heat the object through, so you heat up a thin skin and blow it off. But shear heating by impact with the ground can do that.
The more serious issue is that space activities by signatories of the Outer Space Treaty carries strict and unlimited state-to-state liability to all other signatory states, for damage caused to aircraft or on the ground. In addition, I vaguely recall John Lewis saying that reentering objects create roughly their own weight in NOx.
These factors don't mean that it's not worth talking about or doing; just that it will be complicated (except possibly in fiction).
The idea of the momentum bank is to accumulate a large enough mass that transferring some momentum to a new satellite or other orbital transfer doesn't much change the orbit of the bank.
Transferred momentum would be continuously restored via high efficiency ion/plasma/magnetic drives. It would likely never pay to de-orbit any mass from the bank.
I was about to mention heating via aero-braking but our good host beat me to it! I suppose you could hide behind the asteroid and swarm out to do the necessary working after. Either that, or detach and follow it on a slighter higher/cooler trajectory before rejoining it? Tumbling would be a problem, and better have a space tether arrangement to reclaim the lost momentum!
All wooly brain storming at this stage. SteveO is doing sterling work as the negative feedback loop, and will likely say 'bolomides' to all this!
David Brin:
I deliberately left the mechanism of momentum transfer out, as there are lots of possible ways, and that's an area where we really need to get out there and try things.
My favorite at the moment is to dock a payload at the momentum bank, attach it to a tether, shove it outward a relatively short distance (small rocket, maybe even spring-loaded catapult if you're not in a hurry). The payload starts to fall behind as it moves into a slightly higher orbit - as it does, pay out the tether fast enough to keep up.
Once you've paid out enough tether for whatever orbit or target you're going for, gently brake the tether to a halt - and the payload swings outward, achieving maximum velocity at the top of it's swing.
At that point, it drops the tether and proceeds onward. If going into orbit, it'll be an elliptical orbit, so if you want a nice geosync orbit, you'll need to use a rocket to finish up.
The benefit of this approach is that you can get more momentum transfer with a shorter tether, versus a "beanstalk" approach. Another likely benefit might be faster transit through the van Allen belts.
You can reverse this to send stuff to lower orbits as well, including de-orbiting.
David,
WRT Nitrous oxides, the real issue for deorbiting material is the net release compared to producing the same material here on Earth.
Conventional mining and smelting also tend to produce plenty of NOx.
You know once private enterprise really gets foothold in space there's another class of commodities I can see being worth producing up there.
Illegal drugs.
Heroin is one of the few substances I can see repaying the cost of bringing down from orbit in the short term.
Thanks for the reminder of how long ago I did a launch loads analysis or Pioneers F&G.
I had fun doing that and it is nice that some other folks had fun clearing up the anomaly.
More from Mr Tether Joe Carroll:
http://www.star-tech-inc.com/id121.html
http://www.niac.usra.edu/studies/800Carroll.html
But do tell them that the shuttle burned more aluminum than hydrogen (the bright SRB plumes were molten alumina). Also tell them that vapor or molten-spray processes can give better properties than ingot metallurgy. Read about the Osprey process (used for Mercedes engine cylinder liners, among other things) to learn more.
http://en.wikipedia.org/wiki/Spray_forming
The challenge with debris is partly technical, and partly diplomatic: Russia owns most of it. Anybody who touches it is likely to end up sharing liability for it, so you only want to do that if there's money to be made. (And US policy is that US entities will not touch foreign space objects without the owner's permission. The liability attached to the object means that objects can't be abandoned.)
The UN Treaties merit multiple careful readings. They actually make sense--but you may have to read and argue about them many times before you discover their meaning. They can be downloaded from:
http://www.oosa.unvienna.org/oosa/en/SpaceLaw/treaties.html
Thos links will teach you about electrodynamic tethers!
http://en.wikipedia.org/wiki/Calutron
Seems to be a place to begin thinking further, anyway. The silver electromagnets are pretty odd and interesting history too.
A quick thought about M-bank: the security of investments in the bank obviously depends on a constant or increasing value for Delta-V.
Any big increase in available Delta- V (caused, say, by the deflection of a major asteroid into Earth orbit) or fall in the value os Delta-V (caused, say, by a spsce elevator) could cause major economic disruption (especially if DeltaV was in effect being used as a reserve currency by governments to settle inter-government transactions.)
Ian,
So what you are saying is: Mo-money, Mo-problems?
David,
I've bought a hat (a crushable Fedora) from the Village Hat Shop (they are on line). I've been very happy with it. They sell both a suede and a garment leather version).
Regards,
Hans
whoops. They sell Civil War Kepis in the above materials.
Regards,
Hans
As soon as space law is reformed to clarify mined materials as property, and asteroid mining gets underway, First Orbital can simply store much of the mined precious metals as deposits – no need to immediately transfer it to Earth to borrow against it or even sell it to investors willing to keep it deposited with First Orbital.
But between now & then, don't be surprised if we see some folks in Somalia investing part of their tanker-ransoms in economy-model spacecraft. Old biz model, new territory.
infanttyrone,
And Space Pirates are even cooler than asteroid miners.
(Seriously, I think it was Asimov who said that most space migrants will come from poor non-space-fairing nations, just as most migrants to the US (such as his family) weren't from ship-building nations.)
Chris Claremont actually wrote three science fiction novels that dealt with some of these issues: space piracy and space terrorism. (Also, first contact.) The pirates were funded by corporate interests (via shell groups), while the terrorists were various disgruntled government and military types who felt the world government forming after first contact and the peaceful nature of said contact was against their and humanity's interests (they wanted to go in guns blazing, despite the fact the aliens contacted humanity because they'd encountered a more advanced hostile species and wanted an ally).
The problem with Space Piracy is establishing a base in space. Space capsules have only so much supplies and the like, so holding satellites hostage becomes a waiting game. You wait for the pirates to run out of supplies. And if they have an Earth-based base, then it's open to attack from the U.S. and Russia (and China) who don't want their satellites taken hostage.
Space terrorism is closer, in that any group with the ability to launch a rocket into space (even if not orbit) could have it explode and shower the region with debris, causing a worse-case scenario. But if say Iran or North Korea pulled this type of BS, I very much doubt there would be protest by those nations' protectors over a U.S. strike to eliminate any facilities capable of launching a rocket into orbit because such shotgun weapons are indiscriminate.
Rob H.
My "old biz model" wasn't optimally worded.
I had in mind more of a simple theft of the precious metals and sending them back to Earth to keep (and eventually resell), not to ransom.
This was amusing:
http://www.dailytech.com/article.aspx?newsid=24678
An engineer wishes to build an interplanetary craft, nuclear powered, ion drive, says it would take twenty years to complete. www.buildtheenterprise.org seems to be non-functional, but the dailytech article was fun. There might be better design concepts, Ryk E. Spoor's "Threshold" had a couple of nice ones, but we should get started.
"editrex hroubt", would have given Ford Prefect a terrible time over guide entries.
Paul reminds me of a great old SF short story from the 50's or 60's (I think).
It's set on Mars and all the manual labor in the colony there is being done by people from the Himalayas asnd the Andes because they're adapted to low atmospheric pressure.
They wear relatively simple compressors since the Martian atmosphere was assumed to be a lot thinker than it really is.
So, they're preparing for the first arrival of a series of carbonaceous asteroids that will give Mars a denser more breathable atmosphere. But these guys are just out digging trenches by hand and for them the asteroid's arrival just means the start of the process by which they'll be shoved asde by people from the developed world.
Here's how space piracy might work in the real world: you've got lots of asteroidal material in high parkign orbits.
Someone makes some relatively minor changes to the material's orbit.
Just enough that it'll be expensive and difficult to reloate the material withotu knowign the new orbit - and just enoguh to create potentail legal liability if it collides with something.
Then you sell the new orbital elements to the original owner - or you "find" the material suspiciousl quickly and colelct a reward from the owner or the insurer.
The other form of space piracy we need to worry abot in the near term is ackers takign control of satellites and extorting the owners.
There's evidence satellites have already been taken over briefly but seemingly at least that was simply for lulz.
By burning the satellite's fuel reserves or simply orienting its antennae away from Earthm hackers could permanently incapacitate a satellite or even deorbit it by using the manouevring fuel to send it into a lower orbit.
For all we now, satellite owners have already been successfully extorted. Let's face it, they're not going ot advertise that if they can help it.
Just to go off on a brief tangent, it is touching to see how much Isaac Asimov has touched the collective souls of the computer industry; I say this as I'm abstracting "Communications of the ACM" and found the term "Asimovian androids" in the article - in short, Asimov being identified as the "face" of the humanoid robot.
For all that certain groups try to disparage science and science fiction, the truth is it has already left a deep imprint in the collective souls of humanity and will never truly be completely stamped out, no matter how hard they try. And while in a thousand years humanity may not "know" who Asimov was, he will undoubtedly live on in the collective soul of humanity by the way he touched our imaginations so many years ago.
Rob H.
Indeed. Asimov codified the Three (Four?) Laws of Robotics, on which so many stories are based, and the term 'positronic'. They get the nod in everything from Aliens (see Bishop and his comments about buggy previous synthetics) to ST:TNG's Mr. Data. Asimov may not have invented the term 'robot', but he certainly defined many of the things we hope and fear for from our new cybernetic overlords :)
TheMadLibrarian
cordera ppgrat: Duotronic coding language, a precursor to positronic.
A start-up which includes ATK as a major shareholder is planning to offer "Mission Extension Services" to satellite owners.
The Mission Extension Vehicle will dock with satellites to boost their orbit and thereby extend their operational lives.
http://www.vivisat.com/?page_id=10
As I said here several times now, I think this is one of the big short-term business opportunities in space and could help development of the technologies needed to deliver asteroids into Earth orbit.
Speaking of Asimov's memes taking hold, I think Robert Heinlein's term "waldos" for teleoperated hands should have taken hold. I still call them that but people just look at me with incomprehension. The concept is, of course, expandable to a teleoperated humanoid or even to one of the extremely cool bipedal "forklifts" Sigourney Weaver ran in Aliens.
"Jumper, why do you call your loader 'Waldo?"" "It's a long story."
TheMadLibrarian:
Asimov may not have invented the term 'robot', but he certainly defined many of the things we hope and fear for from our new cybernetic overlords :)
My understanding is that it was PRIOR to Asimov that fictional robots were always seen as dangerous Frankenstein-type monsters, the sort of thing that "man was not meant to tamper with." It was Asimov who changed the paradigm, introducing the Three Laws as safety features and allowing robot stories to be something other than cautionary tales and more like engineering problems.
Maybe I'm just seeing a couple of stars in an odd alignment, but did anyone else see an oddly "comma" shaped object in that milky way image?
Start at the bright center.
Zoom in 6 times.
Look SSE from the center to the large black void with a bright orange star.
Zoom in 3 times more and center on that bright orange star - it appears to have many rays shooting out, presumably a photographic effect.
Follow the dark channel from that star to the left past several bright white stars, and you'll come to that odd looking shape.
Zooming in it still doesn't look like just two stars in a line.
I thought maybe a galaxy - but it seems rather bright for that.
Tom Craver,
It won't be a background galaxy because the bright heart/black channel is the dusty part of the Milky Way, you ain't seeing most of this galaxy in that direction, let alone any other galaxy.
I suspect it's just a nebula illuminated by a red giant (or two). There's a variant nearby. If you're at full zoom on the "comma", zoom out twice. On the left (following along the black channel) there are three bright white stars. Just above the centre/brightest there's another orange blob, centre on that and zoom in again and you can see the orange blur around the star, with a blank streak underneath. The orange glow is dust illuminated by a red giant, the blank streak is thicker foreground dust blocking that glow. You can imagine such thick foreground dust bracketing an illuminated nebula such that only that comma shape is visible. At full zoom, your comma has a fuzzy glow above it. I suspect the bottom is partly blocked by dark foreground dust. Either that or it's an artefact (image or alien.)
Indeed that whole black channel (and all noticeably black parts of the image) is thicker dust blocking the light of background stars. Once you get your head around that, zoom back out, and the whole galaxy looks filthy.
(Excellent directions, btw. Although you should yell "Enhance" after each zoom.)
Omigosh, a lot to follow up on...
Re-entry smelting: Usually there is a lot more going on than just heat - the heat is just necessary to drive the reaction (or a product of it). For steel, you have to blow in oxygen and supply limestone and coke - there is a very delicate chemical reaction you need to feed to get steel (or more precisely pig iron). The Aluminum/magnesium/lithium family is hot but electrolytically refined from oxides, which you are not going to find a lot of in vacuum. Copper chalcopyrite can be ground up and burned resulting in "white metal" an alloy of iron and copper that is then electrolytically refined.
By the way, if you know your minerals, you will probably notice that you are going to find none of these ores "out there."
As far as I know, the only "ore" we know of would be the metal-rich asteroids. If we start with a chunk of metal it is likely to be Ni-Fe-Co with a bunch of other stuff. That is fairly well alloyed, which means that gravity won't separate the elements. If you heat it up and cool it slowly you might get some separation as different elements freeze up at different temps. But that is driven by kinetics, which means the more an element precipitates, the harder it is to get more of it to precipitate (here is a practical use for partial differentiation!). Anyway, you would need some other sort of process to really separate them, and you still end up with mostly iron, which is cheaper here. The more exotic and smaller concentration stuff would still be dissolved and would need to be conventionally removed, so I don't see a benefit to heating it up. Same goes for aerobraking an asteroid (and by the way, YIKES!!) and you are not likely to have enough delta v to pull it out of an orbit that dips into the atmosphere. I would guess that you are losing delta-v to heat the atmosphere much faster than you could replace it with rockets.
On NOX yes we make plenty in pyromet, but it can be captured as it is produced too. Not so much if we just drop stuff.
Vapor metallurgy - so, how are you going to do that without volatiles or gravity? You need something to drive it from one place to another. Electrorefining to me seems a more likely scenario since you will have plenty of sunlight to drive current.
A mo-bank using some high-ISP low thrust system is interesting. A way to build up tiny amounts of delta-v over a long period of time and then use it up in one swell foop. You get the benefits of high impulse with the higher efficiencies of high ISP.
"Waldoes" are used in the nuclear and chemical industries, and are called such.
Again, it is not that it is impossible to get something useful from asteroids, the question is how to even build an economy doing that when we can get everything cheaper already on the planet. And if you think you are not selling for Earthly consumption, you are going to have to show an economic reason and sufficient demand on orbit to justify to it to your investors.
Again, I do not see bootstrapping as an option, since the entry barrier is so massive to even return one pound, even worse for anything at a commercial scale.
*not a grouch, just an engineer* :oP
Speaking of cool "artifacts" in the galaxy map:
Zoom in 5x on the central box.
Slide right to the area of missing blocks.
Center on the cool looking "pink nebula".
Measure the distance from the central box to the nebula.
Look that same distance further right for a missing block by itself.
North West of the missing block is a green spot.
Zoom all the way in on that.
onward
David Brin, your "top ten toxic chemicals suspected to cause autism and learning disabilities" link is broken: is the article it's supposed to refer to at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3404655/ now?
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