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Sir Arthur Speaks
rw2 wrote to us with an interview with Clarke in the NY Times. Login, of course, is required, but the interview is worth reading. Talks about space elevators, Kubrick & 2001 amongst other interesting subjects.
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Did anyone else think of Red Mars and start to worry about the idea of a Space Elevator? At least when a rocket explodes or a satellite orbit decays, it only ruins a small chunk of real estate.
Sure, it would be cool... but you won't catch me moving to the equator.
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QDMerge 0.4!
how to invest, a novice's guide
I'd read about his space elevator concept, both in his books and in actual papers on the subject.. Like all good ideas, it's very, very simple.. But I still thought diamond was the way to go.. I'd never considered bucky tubes.. genius man, genius..
Good Line here:
By the way, I'm an absentee landlord of a hundred square miles of some rather rugged territory near the orbit of Mars. I have an asteroid named after me. Isaac Asimov's got one too. It's smaller and more eccentric.
Ha! Asimov would have loved that..
Let's see here... more browsing.. ah ha! He talks about how he originally came up with the idea for the geosyncronous satellite for communications:
Q. One of the legends about you is that you came up with the idea for Comsat in an article you wrote in 1945 and that you never patented the idea.
A. Oh, so you want to ask me about how I lost a billion dollars in my spare time? Well, you see when I wrote my "comsat" paper, it was 1945....I didn't think that satellites could be launched until the end of the century.... I just wrote this article and sent it off and got £15 for it....what I should have done is to try to copyright the word "comsat." If I'd done that....
Good one.. Bit uninformative of anything new, and definitely the article is way too short.. I'd really like to see an indepth interview, or at least to read about whatever he wants to write about.. Someone like Clarke, well, they're just plain interesting, all the time..
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- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
For those of us who cannot/willnot use the NYT site.
Thanks.
51% percent of survival? I'd buy that. I would like to know what he thinks about that UN population implosion report.
I did not realize that nanotubular carbon was so strong. In high school (it was a long time ago) about I did a paper on Bucky Ball (aka C-60) and it's ability to encapulate RNA for gene repair.
Why can't nanotubes be produced in bulk? What kind of contrants are involved in it's production process?
The problem with a geosynchronous skyhook is that if it breaks, there's a hell of a lot of stuff that's coming down, hard. Fortunately, you don't have to use a skyhook for that. "Space fountains", Lofstrom loops, Jacobs Ladders and other ways of exploiting kinetic momentum could build structures that wouldn't be so tall that they'd span an ocean if they failed; if they were all sited on Eastern shores with nothing but open water to the dawnward, breaking them would only make some waves (ahem).
--
Time is Nature's way of keeping everything from happening at once... the bitch.
In addition to great strength, by changing
the orientation of the carbon rings you can
get a conductor, a diode or a semiconductor.
Extremely cool things. The 1st folks that
can make them in industrial quantities are
going to get fantastically rich.
in re falling skyhooks: couldn't you set it
up so that a disaster would cause a disconnect
at the base so that it would (in most cases)
fall up rather than down? I still wouldn't want
to be on it at the time. I recall some papers
from a few years ago also that showed skyhooks
to be fairly stable, statically and dynamically.
garyr
-- your Web browser is Ronald Reagan
I had the pleasure to meet Sir Aurthur in 1996 on a visit to Sri Lanka and was struck by how incredibly sharp this guy is, despite how frail he seemed when I met him. An old man in a wheelchair he may be, but he has a mind like a razor. Here's hoping he keeps going for a while longer.
Silver
Of course in the Fountains of Paradise, the diamond filament was so thin that you couldn't see it. Walking through it would cut you in half!
The hard part is putting enough weight up in space to be able to lift a large load.. and keeping stability would be tough too. It's like using a baloon.
Imagine the winds and huricanes and natural phenomenon. Plus, there'd have to be alot of cable monitoring systems. Cable would need to be replaced.
Pan
I said no... but I missed and it came out yes.
He was knighted after all? I thought that the flap over charges that he is a paedophile caused the British to withdraw the offer of knighthood. Does anyone have the story on this?
In respects to buckytubes, I thought we were just starting to produce them in industrially significant quantities a year ago. I was hearing about all sorts of applications for them, from structural materials to ultra-thin computer monitors. What happened? Where's all the cool new toys? :(
"Read a book!!!" - Handy (longtime companion of the Human Ton).
Hmmmm... perhaps it's time to change my sig line? ;-)
Zontar The Mindless,
Il n'y a pas de Planet B.
Q. One reason you advocate space travel is fear of asteroids?
A. I'm always quoting the science fiction writer Larry Niven that "the dinosaurs became extinct because they didn't have a space program."
Or electricity for heaters, or bomb shelters, or the ability to grow food without soil or direct sunlight, or the ability to clone species, or yada, yada, yada. If we have the ability to relocate a large enough population to an acceptable destination, I'm gonna guess we can stop an asteroid (yes I know how difficult it is).
+&x
login: uncle_duke
password: trudeau
And of course the country is American Samoa!
cypherpunks321 (pass=cypher)
or create your own account.. it's free and you don't even have to give them a real email address, they don't mail you your password or anything.
The above account is made out for a male from Uruguay with email guest@hotmail.com. So if, you're paranoid, they won't know anything useful about you.
---
I hope you're not pretending to be evil while secretly being good. That would be dishonest.
simple.
ensure the center of gravity of the breakaway portion is at greater than geo orbit altitude.
this makes for 2 nice properties:
1. cable always in tension ( centrifugal force
pulling cable out like tennis ball on a
string.
2. in event of breakaway, fall "up"
unfortunately, our idiotic government would never cough up the funds to do basic development of the components necessary to build such a thing...
I am 32 yrs old.
When I was 5 ( 1972 ) it was reasonable to believe that within my working lifetime, I would be able to go to orbit as a tourist.
we were progressing that fast. the technology (except HAL) of 2001 was reasonable. everything (technologically speaking) in that movie COULD have happened by now.
somewhere along the line we lost our way.
the government fell in love with the space shuttle, a brilliant idea, flawed execution.
the government fell in love with the space station, again good idea, crappy execution.
if we had only....
The difference between Theory and Practice is greater in Practice than in Theory.
I thought we were discussing A.C.C.'s ideas, and the logical extension of same, such as buckytubes and skyhooks (an interesting discussion thus far). Perhaps the subject of his sexual proclivities ought to be discussed elsewhere.
I don't know about anyone else, but AC is truly "THE MAN" in my book.
In all honesty I don't know of anything that I can find at fault with him (other than his Mysterious World of Arthur C. Clarke which, I will admit, is truly entertaining to watch, but is total bunk science.)
Anyway, to this day whenever I pick up one of his books, the first thing I think of when I read something about some gizmo is "okay...." but then I soon say "Wow!" when it finally sinks in just what the thing does.
If there should be a patron saint of /., AC gets my vote.
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8012456989047663620151201231566801865112556408748
It wouldn't be particularly nice to be around, like a broken steel cable whipping into its attachments and ripping up anything that gets in its way. It would be best to be elsewhere.
--
Time is Nature's way of keeping everything from happening at once... the bitch.
Given the fact that this item is up on the NYT home page and not buried in a paper somewhere (although I'm sure it's there, too), I wonder what Sir Arthur's connection to all this technology that he's always seemed to predict is. Does he use the Internet? Does he think computers with HAL's intellect will one day exist and should we fear them?
He'd make a great target for a Slashdot interview. The questions from the NYT were nice, but I don't think they were posed by a geek. Given the reverence to which we hold Clarke, I'm sure that if we were asking the questions, you could probably write a whole 'nother novel with the answers.
He might be alot of things, but I saw your picture in the dictionary under "dickhead". Whatta moron.
Too bad the author didn't get a chance to talk about 3001. I felt like such a sucker after buying that - I found it really immature and ideological. What could he have been thinking? He seems pretty smart in the article, I guess he just doesn't take his fans too seriously. Alas
Can your IM do this?
there's one for ya
OK, I'm ignorant. In English, what are they?
And how likely is it that they'll be cheap enough to do what he is proposing anytime soon?(and he said it'd still be $1 trillion, where's that budget surplus?)
We must stop promoting this disgusting puritan attitude that there is somehow something wrong with sex. You need to be flogged repeatedly. Children should be introduced to sex at the youngest age possible, in order to not pervert them as society has done. If arthur c clarke is a pedophile, that is just another facet of his genious.
I think this has been answered pretty well by othre posts, but -- it's not quite a geosynchronous orbit. If were perfectly geosynchronous then something like a hurracaine could pull on the cable and yank the entire thing down. You pull it down enough with the cable that the cable is tensioned and will resist environmental forces that would tend destabilize it. You'd still get standing waves in the cable, but I gather these are not as big a problem as they could be.
anyway, this means that the centrifugal force is larger than the gravitational force. So, if you just let go of the bottom of the structure it should be hurled away from the earth like a fanblade. In the aforementioned Red Mars Scenario terrorists blew up the anchoring satellite. Losing the ballast like that make it fall to earth regardless. Lacking an anchor point it may do less damage, but still a big mess. Megadeaths, bad press, angry investors. An all around bad day for everyone.
garyr
-- your Web browser is Ronald Reagan
The energy requirement to significantly change the orbit of a 10 km asteroid is roughly equivalent to what it takes to accelerate at least a few million people to the speed of light. Asteroids are heavy, people aren't - it's going to be a lot more energy-efficient to move the people. Plus, once we have a few hundred million people in space the population not living on earth will likely explode just as it did in the Americas from 400 or so years ago.
Energy: time to change the picture.
Trust me on this, they are plenty stable. If I remember correctly, they have something like 4 or 5 times the needed tensile strength... Although I could be forgetting.... (it might be like 2 times... But I'm pretty sure it's more). I once knew ;)
Ok, technically, to a significant fraction of the speed of light. The calculation is pretty simple:
Gravitational energy of asteroid = 1/2 M v^2
where M = Volume * density.
Volume = 4/3 * pi * (5 km)^3 (if the diameter is 10 km) = 5*10^11 m^3
Density = roughly 4*10^3 kg/m^3
so M = roughly 2*10^15 kg
The size of this asteroid mass is what's important - it's enormous compared to anything we can handle with any remotely available technology today.
If we can strap rockets to an asteroid like that and significantly change its orbit, we can certainly send a number of people roughly equivalent to that mass into space to fend for themselves. If each person weighs on average 100 kg and requires an extra 100 kg of luggage, that means that if we have the ability to move an asteroid that size, we also have the ability to put into space 10^13 or 10 trillion people.
We'll be populating space in the billions long before we can move asteroids around much. And Clarke's point that we need to get into space to avoid our "single point of failure" here on this planet is very very important.
Energy: time to change the picture.
I attended a NASA space elevator workshop earlier this year, and I'd like to make a few comments. First of all, the cable hanging from synchronous orbit is not an optimum design. Large structures have to support all the load at each point. So a cable hanging down is smallest at the bottom, and each unit of length going up has to be an increment thicker to support the added weight of that length of cable. So as you go up the cable cross section gets exponentially bigger, because thicker cable in the higher sections add proportionately more load. Now consider a tower built up from the ground, using the same type of high strength materials as the cable would use. A tower will show the same type of exponential taper, but with the fat portion near the ground (i.e. it will look like the Eiffel Tower). For a minimum weight design, you would build a tower up from the ground and have it's top meet a cable hanging down from orbit. To put some numbers to it, assume you have 2 million psi carbon fiber of the buckytube flavor. A constant section strand 800 km long at one gee can just support it's own length. The physics of the situation says the cross section needs to increase by a factor of e (2.718..) every 800 km to keep from breaking. The earth's gravity well is the equivalent of 6400 km deep due to the fall off of gravity with height. So a cable hanging all the way from synchronous orbit, which is only 2% from the top of the gravity well, needs to be about e^8 times the mass of whatever you are lifting, or about 3000:1. If you have a tower and a cable, each e^4 times the cargo weight, then the combined weight is 110 times the cargo weight. This is a much simplified analysis. In the real world, you will have factors of safety and redundant design, overhead beyond a bare cable to deal with. Also, the tower, being close to the ground is presumably cheaper to build than the stuff in orbit. Finally, compressive and tension strengths for the same material are not the same. But the basic idea is that a cable all the way from orbit is not optimum. Secondly, buckytubes are presently made at a cost of $800/gram, a few grams at a time. Work is being done on scaling up production and bringing down cost. If it gets down in the range of $10/gram, people will start using it in places where weight is extremely critical (that's about the cost to launch things into space for example). Thirdly, long cables in orbit MUST be damage tolerant and have self-repair capabilities because man-made space junk and natural meteoroids WILL run into it. For example, you can have 6 main cables, any 4 of which can carry the load, with cross-straps every 10 km to re-distribute the load around a break. The cables need to be separated by more than the width of the widest thing that can run into it (think space station = 120 m wide). When a cable gets broken, a "repair spider" runs out to the break with a replacement spool of cable, winds in the broken pieces, and installs the new one. Fourthly, in the near term, a full up space elevator is not economic. Single-stage to orbit rockets are marginal on having payload (88% fuel, 10% structure, 2% payload). So anything you can do to relieve them of some of the rocket propulsion job can have a dramatic impact on payload capacity. So a tower going up from the ground in the range of 10-100 km (which can be done without buckytubes), and a cable in orbit to catch the rocket which is 100s of km long can help a lot, and can be done with existing carbon fibers.
Hey,
The account that Slash gives us seems to point to page, but not the one i was (we all are) looking for. Tried to find it in the archive but you seem to have to pay for it. Is there anyone that knows a working URL?
-Rejo.
I'm afraid that bucky- structures are not exactly connected triangles of carbon. The buckyball would be a bunch of connected triangles, if nature hadn't cut off all of the tips and created those pentagons. What you end up with is a truncated icosahedron--better known as a soccer ball. This structure has the same symmetry group as the icosahedron [the triangles] but is instead made up of 20 hexagons and 12 pentagons.
If you open any organic chemistry book, you'll notice that carbon seems to like to bond together in rings of 6, hexagons. Carbon seems to support hexagons, pentagons and heptagons with relative stability.
errrr hehehe,
Did you think that up yourself stupid, or did your mommy tell you that one?
Idiot!
You dickheads are coming in your pants over ACC, he's a fucking nobody!
Why don't you give some credit to guys like Steven Hawking who make sci-fi become reality?
Or does that require too much sensibility for you custard boys???