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This phrase did not mean regulation in the since of restriction; it was synonymous with proper function and order in the vernacular of the day.

In small amounts, tritium is not harmful, even if you eat it.

http://yarchive.net/gun/tritium.html
"The biological half-life of tritium (how long it stays in the body) is only a few days because its tritium oxide, the most common form, is chemically almost identical to water."

Well. the state doesn't confiscate the business. And I'm not saying copyright should stop at death. But copyright already extends for decades after death. That period when thay can collect money is a gift (aka copyright) from the State, and saying there has to be some limit, sometime, at which the heirs stop collecting the money is not snatching the money away.

The vast majority of creative works are long out of print/deleted from catalogues, and provide an exponentially declining (or zero) income to the heirs (or the corporations they sold the rights to, 40 years ago). Only a few have any potential for producing income, and copyright extensions lock up all works for the benefit of a very few rights holders.
(the simplest solutions id for the holders to be required to do some minimal work for their money: like registering and paying a nominal fee evry 10 years after the 50 years are up...

See what Lord Macaulay (a successful published author, incidentally) said against the extension of copyright, 165 years ago.

In the last discussion we had. You're getting very close to troll territory my friend.

REPOST:

With all the talk lately about a space elevator, I got to thinking after recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp, (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to the tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere [gatech.edu], with it's associated weather and air pressure, and have little to no fuel needed to escape the earth's gravity, meaning you could do a lot more while you were up there. At normal launch accelerations you can get to LEO with very little external propulsion.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005 [space.com], and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

Space has got vast, essentially unlimited resources. One recent story pointed out the trillion dollar iron asteroid up there. The thing has about 5 tons of steel for every man, woman and child on earth. And thats just one of god knows how many... billions more?

Once we leap the cost to escape hurdle (as I think I have managed), we can proceed to use these resources. There are several obstacles in the way of this, first of which is zero gee mining, we have no idea how to do it. We can either mine the ore out there, or bring the asteroid back into orbit and slice it up there. Or slice it up and send it back to orbit. I would be opposed to moving it back into orbit for processing, purely for the debris issue. Perhaps a lunar base would have some merit there.

So we set up a mining and processing operation either on the moon or in deep orbit, and start cutting and processing one of those bad boys. Whats the first thing we build? A bigger processing and mining operation. Space exploration, much like the internet, has to be a largely incestuous affair at first, existing solely for its own benefit.

Once we have that mastered, we can move to algae pods in orbit for food production, oxygen refining, and fuel production (biodiesel or chemical engines), all of which can be powered by the immense energy of the sun, and use the raw materials abundantly available in space. Whether you ship that stuff back to earth or use it for further colonisation, its a vital step.

The production of automated scouts is also a high priority; a vast amount of surveyor and prospector drones to sweep and map every square inch of every rock and gas in the system, out to the Oort cloud, and figure out what they are made of. I'd err on the side of quantity rather than quality, still no reason not to have either. This could be combined with deep space observatories that would make hubble look like the end of a coke bottle.

So now we have a manufacturing bridgehead, a good idea of what's interesting out there, and a cheap means to launch to orbit. Actual manned system ships would come next, to either colonise or investigate the system. The rest, as they say, is (future) history.

A lot of this would require automation, robotics, right up to the point when we build a larger manufactory from the orginal small one. Robots would als

Yet within the realm of science, we didn't have to advance much to get from one to the other. We needed an understanding of rocketry, some knowledge of life support, some advances in various engineering disciplines.

So you are telling me that the leap from canvas winged powered kites to putting men on the moon wasn't much of an advance?

Moreso in space since you've got to take into account the limitations imposed by automation, or else deal with the problems associated with long term space habitation and life support, and you've got to get from Earth orbit to wherever it is in the asteroid belt you're planning to mine/build

What limitations? I wasn't proposing an AI to drive them, more like remote piloting with certain systems semi autonomous. With that in mind there are no limitations on automation. And its a whole lot easier to get from earth orbit to wherever than it is to get from the earth's surface to wherever.

Have you checked the price of putting something in even LEO lately? We need to make serious improvements to our launch technology first if we're going to do anything like building stuff in the belt.

Heyyy, wow did you ask the wrong man. Here's an older post I made....

With all the talk lately about a space elevator, I got to thinking after a recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to escape the earth's gravity, meaning you could do a lot more while you were up there. At normal launch accelerations you can get to LEO with very little external propulsion.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

Space has got vast, essentially unlimited resources. One recent story pointed out the trillion dollar iron asteroid up there. The thing has about 5 tons of steel for every man, woman and child on earth. And thats just one of god knows how many... billions more?

Once we leap the cost to escape hurdle (as I think I have managed), we can proceed to use these resources. There are several obstacles in the way of this, first of which is zero gee mining, we have no idea how to do it. We can either mine the ore out there, or bring the asteroid back into orbit and slice it up there. Or slice it up and send it back to orbit. I would be opposed to moving it back into orbit for processing, purely for the debris issue. Perhaps a lunar base would have some merit there.

So we set up a mining and processing operation either on the moon or in deep orbit, and start cutting and processing one of those bad boys. Whats the first thing we build? A bigger processing and mining operation. Space exploration, much like the internet, has to be a largely incestuous affair at first, existing solely for its own benef

2. Equipment not working at -40.

Considering that these ships are intended to be used by the coast guard in the gulf of Mexico, I don't see the problem.

3. Unshielded cables.

WTF is he talking about? The only way to sniff data from an unshielded cable is if you are right next to it. It is not going to help you when the cable is on a ship in the middle of the ocean. Further, the moment data is transmitted off the ship via radar, all bets are off. Unless you encrypt it *anyone* can listen to it.

• Gulf of Mexico != middle of the ocean - but that's just a nitpick
• RADAR != transmission device - see RADAR
• Maximum distance to electrically sniff from an unshielded cable != right next to it - see TEMPEST
• Encrypting something != only you can listen to it - it simply means that other folks will have a hard time understanding it which is a critical distinction

Insisting on absolute safety is for people who don't have the balls to live in the real world.

-- Mary Shafer, risks researcher, NASA

Aha, Google eventually found something:

http://yarchive.net/space/shuttle/shuttle_control. html

According to Mary Shafer herself:

"After the first S-turn on STS-1, the entire re-entry was hand-flown through STS-4, at which point the FCS was rewritten (and the e-seats removed). John Young took over the flying when the sideslip meter pegged and stayed pegged for several seconds, meaning that the limit had been exceeded. This happened because L_YJ was about half the size predicted and the wrong sign and not even the extremely robust FCS could deal with that much error. Cf Iliff & Shafer, "Extraction of Stability and Control Derivatives From Orbiter Flight Data", NASA TM-4500, June, 1993."

There might be methods whereby you wouldn't need to carry the fuel with you, for example with a space elevator. However, just what advantages would a space elevator offer over a tower launch? (I've used parts of this post before, but I have since refined my ideas). I contacted a man responsible for a similar idea a while back, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to match the earth's gravity, meaning you could do a lot more while you were up there. At a reasonable acceleration (5 to 7 g's) you would be in geostationary orbit. From there you could build a fully system wide ship or ships, as its much easier to escape the planet's gravity from GEO than from the surface.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

So, what you're saying is: Her survey needs a some patches?

---

Insisting on absolute safety is for people who don't have the balls to live in the real world - Mary Shafer, NASA

I would like to ask your opinion of an idea I have... With all the talk lately about a space elevator, I got to thinking after a not so recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to reach GEO, meaning you could do a lot more while you were up there. I originally estimated reaching escape velocity with this system, but it turns out I got the numbers wrong and that would only be suitable for electronics and things that could withstand insane G-forces.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Consider the big dig in Boston has cost about 12 billion so far... Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years.

Its not FTL but baby will it get the ball rolling. I'll just run this by everyone here... With all the talk lately about a space elevator, I got to thinking after a sort of recent slashdot discussion, just what advantages would a space elevator offer over a tower launch? I contacted the man responsible for a similar idea, the skyramp (warning: hideous javascript menu may break firefox), Carlton Meyer, and had a dialogue in which he pointed me to a tower launch archive.

The ideas I see bandied about there are similar to what I had in mind, which would be essentially an 11km tall tower (think pylons rather than skyscrapers, based at sea), with evacuated airless launch tubes, using nuclear reactors to power a maglev or pulley system to accelerate vessels to escape velocity. These would then emerge above the end of the troposphere, with it's associated weather and air pressure, and have little to no fuel needed to escape the earth's gravity, meaning you could do a lot more while you were up there. At 1m/s acceleration, you would be at escape velocity when you exit the top of the tower.

Not only would this enable multiple launches daily, it is, unlike the space elevator, readily achievable with today's technology, and financially viable as well. Given NASA had an annual budget of $16.2 billion for 2005, and a nuclear power plant costs a cool billion to build, give or take, we could have this up and running in a few years. And once we are up there...

Space has got vast, essentially unlimited resources. One recent story pointed out the trillion dollar iron asteroid up there. The thing has about 5 tons of steel for every man, woman and child on earth. And thats just one of god knows how many... billions more?

Once we leap the cost to escape hurdle (as I think I have managed), we can proceed to use these resources. There are several obstacles in the way of this, first of which is zero gee mining, we have no idea how to do it. We can either mine the ore out there, or bring the asteroid back into orbit and slice it up there. Or slice it up and send it back to orbit. I would be opposed to moving it back into orbit for processing, purely for the debris issue. Perhaps a lunar base would have some merit there.

So we set up a mining and processing operation either on the moon or in deep orbit, and start cutting and processing one of those bad boys. Whats the first thing we build? A bigger processing and mining operation. Space exploration, much like the internet, has to be a largely incestuous affair at first, existing solely for its own benefit.

Once we have that mastered, we can move to algae pods in orbit for food production, oxygen refining, and fuel production (biodiesel or chemical engines), all of which can be powered by the immense energy of the sun, and use the raw materials abundantly available in space. Whether you ship that stuff back to earth or use it for further colonisation, its a vital step.

The production of automated scouts is also a high priority; a vast amount of surveyor and prospector drones to sweep and map every square inch of every rock and gas in the system, out to the Oort cloud, and figure out what they are made of. I'd err on the side of quantity rather than quality, still no reason not to have either. This could be combined with deep space observatories that would make hubble look like the end of a coke bottle.

So now we have a manufacturing bridgehead, a good idea of what's interesting out there, and a cheap means to launch to orbit. Actual manned system ships would come next, to either colonise or investigate the system. The rest, as they say, is (future) history.

A lot of this would require automatio

Dangerously strong pogo oscillations, which could have ripped the engine off the rocket, happened to trip a pressure sensor which caused the computer to shut down the engine.

Pogo was reduced to tolerable levels by the end of the Apollo series, and later engines such as the SSME were designed to eliminate it entirely.

Not like they didn't come close... (search for "pogo oscillation")

Sadly, that is no longer the case. Individuals have and continue to come into court and consistently get their way at the expense of the public. They do so routinely. The Supreme Court of the United States even upheld Congresses right to apply copyright retroactively with the Sonny Bono CTEA. Personally, I like this quote better, it seems much more relevant:

Just as the absurd acts which prohibited the sale of game were virtually repealed by the poacher, just as many absurd revenue acts have been virtually repealed by the smuggler, so will this law be virtually repealed by piratical booksellers. At present the holder of copyright has the public feeling on his side. Those who invade copyright are regarded as knaves who take the bread out of the mouths of deserving men. Everybody is well pleased to see them restrained by the law, and compelled to refund their ill-gotten gains. No tradesman of good repute will have anything to do with such disgraceful transactions. Pass this law: and that feeling is at an end. Men very different from the present race of piratical booksellers will soon infringe this intolerable monopoly. Great masses of capital will be constantly employed in the violation of the law. Every art will be employed to evade legal pursuit; and the whole nation will be in the plot. On which side indeed should the public sympathy be when the question is whether some book as popular as Robinson Crusoe, or the Pilgrim's Progress, shall be in every cottage, or whether it shall be confined to the libraries of the rich for the advantage of the great-grandson of a bookseller who, a hundred years before, drove a hard bargain for the copyright with the author when in great distress? Remember too that, when once it ceases to be considered as wrong and discreditable to invade literary property, no person can say where the invasion will stop. The public seldom makes nice distinctions. The wholesome copyright which now exists will share in the disgrace and danger of the new copyright which you are about to create. And you will find that, in attempting to impose unreasonable restraints on the reprinting of the works of the dead, you have, to a great extent, annulled those restraints which now prevent men from pillaging and defrauding the living. -- Thomas Babington Macaulay

Insisting on absolute safety is for people who don't have the balls to live in the real world.

-- Mary Shafer, Risks researcher, NASA Dryden

From here.

No, that's a common misconception.

Or even worse, the lack of an unsigned byte when reading in binary data structures. I don't claim to be a Java expert by any stretch (so I may be missing an obvious way to do this), but do you know how unnecessarily complex it is to convert a read-in byte to it's CORRECT unsigned value? Why isn't there an automatic way to do this at all? You can't just assign the byte to an int, as it'll still be negative (if above 127). I think in the end I just asigned the byte to an int, then did a bitwise-AND to throw out the extra sign bits it tacked on in the widening conversion so that it was back to positive.

InputStream.read() doesn't return a byte. It returns an int between 0 and 255 inclusive. -1 means EOF. The most common idiom is to do something like this:

int i;
int numRead = 0;
while ((i=inputStream.read()) >= 0)
    someByteArray[numRead++] = (byte)i;


For bytes with values between 128 and 255 inclusive, the values will become negative. And why do you care? As long as every single one of the eight bits in each byte is correct, signed vs. unsigned is in the eye of the beholder. It doesn't enter into anything unless you start doing arithmetic on the bytes or print their numeric values, both of which involve implicit casts to int. To do arithmetic, Java always converts a byte, char, or short to int using an automatic, implicit cast (it converts float to double as well). If the bytes have unsigned semantics in your program, then never allow the compiler to implement an implicit cast since implicit casts assume signed values. Replace them with explicit casts that mask out the top 24 bits to zero yourself, preserving the semantics with respect to sign:

int intVal = (0xFF & byteVal)

When evaluating this expression, byteVal will be implicitly cast to a signed int and then the & operator zeroes out the sign extension bits to preserve semantics. Is this "unnecessarily complex"? I don't think so. I rarely even need to do it.

This seems to horrify people used to the unsigned-type train wreck in ANSI C but I would not welcome unsigned types being added to Java at all. The existing type system in Java is perfectly adequate for getting work done and you don't have to keep remembering whether variables were declared as signed or not if you know they're always signed.

Mercury forms an alloy with lead at room temperatures.

Mercury bullets are an urban legend.

Launching into the Sun is energetically wasteful; the needed delta-v is about 30 km/s, as opposed to 16 km/s or so for the Solar escape trajectory, i.e., leaving the Solar system forever. There are even less demanding and arguably better destinations, see this discussion for the list of possibilites.

(The assumed "garbage" is concentrated, long-lived radioactive waste; the feasibility of launching other types of waste is questionable.)

Now perhaps SC has found an engine that will get them to orbit, who knows, but it's a bigger problem than you might think. Fuel is an issue:

Fuels that are used in space must carry their own oxygen, but when going at high speeds in the earth's atmosphere, why not make like a jet engine and get oxygen from the atmosphere?

Now perhaps SC has found an engine that will get them to orbit, who knows, but it's a bigger problem than you might think. Fuel is an issue:

Fuels that are used in space must carry their own oxygen, but when going at high speeds in the earth's atmosphere, why not make like a jet engine and get oxygen from the atmosphere?

Now perhaps SC has found an engine that will get them to orbit, who knows, but it's a bigger problem than you might think. Fuel is an issue:

Fuels that are used in space must carry their own oxygen, but when going at high speeds in the earth's atmosphere, why not make like a jet engine and get oxygen from the atmosphere?

Now perhaps SC has found an engine that will get them to orbit, who knows, but it's a bigger problem than you might think. Fuel is an issue:

Fuels that are used in space must carry their own oxygen, but when going at high speeds in the earth's atmosphere, why not make like a jet engine and get oxygen from the atmosphere?

The big block engine may be too heavy. You have to look at tables of "Thrust to Payload" ratios to get a good idea of efficiency. http://www.spacefuture.com/archive/a_single_stage_ to_orbit_thought_experiment.shtml

The idea of the Shuttle is to work as a service module and to allow astronauts to exit and re-enter the vehicle. Rockets are still used to launch satellites--but they can't be used for space stations and repair missions. Or at least, you would have to add a lot more of a return payload to the lifting body and add other complicated devices that would have to be thrown away. So the thought is, by the time you fix a rocket to do this type of work, you are better of with some kind of shuttle (not necessarily the one we have).

There is also the Delta-V to consider. Weight of propellant is not the only issue--its Volume to Mass ratio also has an effect, giving denser fuel an advantage. http://yarchive.net/space/rocket/fuels/hydrogen_de ltav.html

Anyway, the ideal engine would be an Atomic engine for real power. But say "Nuclear" to anyone and rationality goes out the window. http://www.nas.nasa.gov/About/Education/SpaceSettl ement/75SummerStudy/4appendM.html But it is quite feasible to create a safe and effective nuclear rocket.

It's also lethal. The amount in typical car A/C system could kill you if released into the passenger compartment. http://yarchive.net/ac/r134a_lethal.html

And there's every chance that the motor-generators did more than provide intertia. A lot of mainframes use 400Hz AC power. The higher frequency means transformer cores can be smaller, and there's less ripple after rectification so filter capacitors don't have to be huge. "Rotary converters", as they're called, are a good way to convert betwixt DC of various ground references and AC of various frequencies and phases.

You'll find 400Hz-tolerant power supplies in a lot of millitary hardware too, as shipboard power is also 400Hz. I have some gear that'll take anything from 100-250 volts, 47-450Hz.

Of course, the other power philosophy says AC is silly, just use batteries and make all your equipment run natively from the DC power plant. If you're always on DC, there's no hiccup when the rectifiers lose their input.

About coal being worse than nuclear, I have not the best references, but here are a few:

http://geology.cr.usgs.gov/energy/factshts/163-97/ FS-163-97.html
http://www.ornl.gov/info/ornlreview/rev26-34/text/ colmain.html
http://yarchive.net/nuke/coal_radiation.html

here's the link to the above archive (which is an archive from usenet, BTW)

http://yarchive.net/med/litigation.html

glad to see someone else is reading yarchive, and in paticular, Steve Harris, MD

Steve, if your reading this, Thanks for posting all that stuff to usenet.

There are exploding parts, The nuts holding the orbiter to the platform blow on liftoff. The eight giant bolts holding the orbiter to the platform are severed at launch.

The shuttle's SRBs would take the platform up with it if the bolts are not blown. I believe this is the last possible thing to go wrong that you can pull back from (At like t minus .01) before the candle is lit.

http://yarchive.net/space/spacecraft/explosive_bol ts.html

You have way too much obsession with children in this matter, continually bringing them up, and the fact that you think of dead children sexually, even if just to make an ad homiem attack, is disturbing.

If you're gonna link to faked documents, at least link to those that look authentic, and that don't use Copperplate Gothic Light font instead of something standard like Courier. Having all the references to the documents not be conspiricy websites would be nice too.

Is this the same MacArthur that wanted to nuke China? It doesn't really matter what he thought, since some Japanese historians went to the trouble of compiling an account of what actually happened. Read The Longest Day - an account of 14 Japanese Historians about the surrender, or this summary.

Since you claim you understood my post, yet did not believe it, you clearly have no knowledge of feudal Japan to WW2. Instead you make ad homiem attacks and strawman arguemnts that latch onto a phrase that shows how fanatic the Japanese were. I pity you, never understanding the world around you, yelling louder and louder and being ignored more and more, secure in your delusions that there's an evil govt consipricy and anyone who doesn't see is a drone, and never bothering to do some actual questioning and factfinding.

This sounds like the stuff that Tera was working on with their MTA back in the 90s (see this or for more techincal details here). Basically, a processor that could handle up to 128 threads at a time, with almost zero-latency switching among threads. These processors could be easily interconnected to scale up to whatever the customer (e.g., Sandia, Los Alamos, LLL) wanted. From perusing Cray's website, though, I don't see any current machines that appear to be using that architecture, so I assume it didn't play out somehow.

SCI-FI is fiction. Please say that again and again till it starts to sink in.

Except when it's not. The archangel's design is considered sound by scientists and has been discussed several times on nuclear science webboards. I've asked nuclear scientists outright if the archangel's defenses would work. The answer was a resounding 'yes', along with an explanation about the issue with reflective surfaces.


Yes, Masers can use wavelengths higher than visible light but if your going to use some sort of mirror to target your system then clearly you can use that type of mirror to reflect that energy at 99+% efficiency. At this point in time your talking about a hypothetical system so feel free to pick any part of the EM Spectrum and you can find it's going to be a pain to use as either you need to rapidly swivel your laser system or you going to lose a lot of energy as it passes though the air or you can use the same substance used in your mirrors to make a missile immune to said system.

We're discussing both systems, so it's only fair to mention both. Lasers have a faster targetting system than masers (due to the ability to reflect visible wavelengths), but masers are able to penetrate better due to higher wave lengths. Both have advantages/disadvantages that to be weighed in before deploying a system. A mirror on a high powered laser is doable, but has to be precision crafted to be able to take the load. Note that such a mirror is vastly different from a "reflective surface" on a missile. From here:

The optical power levels inside the laser devices themselves are so horrendously high that the high-reflectivity laser mirrors operate just on the verge of self-destruction. Any flaw or blemish or dust particle on the mirror surface causes the mirror reflectivity to decrease or its absorption to increase. As the absorbing spot gets warmer, its absorption goes up, and the situation goes to pot in a runaway fashion. The result is near-instantaneous catastrophic runaway thermal damage which blows the surface off the mirror faster than you can possibly shut things down. The supersonic nozzles are
extremely fragile and touchy also.

While you can "use the same substance" as you suggest, it's doubtful that you could maintain the perfect mirror on the missile, or for that matter even acheive such a mirror.

You can't fire rail guns over the horizon as they a lose a lot of kinetic energy going tough the air and don't don't have ballistic trajectories unless there moving at slow speeds at which point you can just use gun powder to do that.

You obviously haven't seen the Raytheon specs on the new railguns. They fire a non-explosive, guided projectile straight up, then direct it to the target on the way down. Over the horizon is *EXACTLY* what it does, and it does it with a range of ~100 miles. (Or so the brochure says. :-)) Some links:

http://www.navyleague.org/sea_power/may_04_10.php
http://www.raytheon.com/newsroom/articles/ddx_jane s_062403.pdf
http://www.strategypage.com/messageboards/messages /8-6263.asp

I'd provide a link to the munition itself, but I can't find the article at the moment. If I find it, I'll add it in another post.

And its not very likely that someone who's caught recorded harrassing someone and thratening to withhold paychecks, etc., is going to be in any position to complain.

Here's some law: http://yarchive.net/phone/call_recording.html - phone conversations

I have used tape recordings of my own phone calls in court. According
to FCC rules, only one party to the conversation (that's me) now must
to be aware of the recording. In other words, third party wiretapping
is still illegal but it is not illegal to record your own
conversations.

Participant recording
Because Michigan's definition of "eavesdrop" is to "overhear, record, amplify or transmit any part of the private discourse of others," Michigan courts have held that participant recording (even without the consent of the other parties) is not prohibited. Therefore, a party to the conversation can record the conversation himself without obtaining the consent of the other parties. He cannot, however, employ a third party to record the conversation on his behalf without getting the consent of all the parties.

Solar-sails do not use solar-wind at all. This is a common misconception, but the appealing analogy does not apply.

See Henry Spencer comments for more details.

On the other hand, magnetic-sails do use the solar wind, but they are a completely different beast.

Disks on trucks present enormous heat dissipation problems because
there is insufficient area to cool them unless multiple disks are used
as on railways where as many as four 400mm diameter 100mm disks are
uses per axle of a passenger car. This is an enormous expense but is
necessary because skidding is so hard to control with any other brake.
There is nothing "traditional" about brakes on highly competitive long
haul trucking. Multiple disks are not a viable option for trucks.

Scramjets only look good under certain assumptions.

They are good if you want to go within a certain range of speeds within the atmosphere. The problem is, they still need air to function, so you'd still need to carry oxidizer and you'd still need to carry a rocket engine.

The scramjet program doesn't get killed repeatedly because of ill-timed plans. It gets killed because we haven't been able to do a good set of tests on them... until last year. And they are the sort of thing where if you get 'em wrong, you've just wasted a LOT of money. So every time we've tried to do any sort of air-breathing engine -- scramjet, ramjet, turborocket, or intercooler -- it ends up getting pushed off because it increases the design risk too much. The problem is that the scramjet partisans make it sound so good that you forget that they are so far from production that they could be totally wrong and not realize it. And, yeah, scramjet money is money well spent in the same way as money on FTL travel research, teleportation, cryonics, fusion, and other far-out stuff. It may very well be money down the drain, much like trying to transmute lead into gold was in days gone by, but it would be so useful to have that it's dumb to not at least take a good solid scientific look at it.

The Falcon I is memorable because it's the lowest cost, per launch, so far. The Falcon V will be the lowest cost, per pound, so far. With the decided potential to lower the costs further over time, as they realize the economies of scale and also the advantages of partial reusability and (hopefully) improved reliability.

The problem with any air-breathing vehicle is that you change your trajectory in such a way as to create more drag. Remember, a conventional expendable booster can be aluminum, which gets soft and melts at astonishingly low temperatures, as space-age materials go. Why? Because it goes up first, to get out of the atmosphere, and then starts to accelerate.

Air-breathing vehicles require a longer time in the atmosphere, or else you are wasting the weight and whatnot involved in making it airbreathing. Now, this helps because your thrust-to-weight ratio doesn't need to be so high because you can use wings to create lift and whatnot. But this still creates drag and heating. This makes the heating worse, in fact, because you are accumulating far more energy. This also means that you need to output more energy to overcome the drag.

The problem is we have way too little information to really make a good determination as to weather a scramjet is going to work or not. I'm not trying to say that scramjets won't work... I'm just trying to say that they are not a sure bet.

The interesting part about our knowlege of engines since the SSME is that the main thing we've learned since then is that the SSME is too complicated. The real tragedy of the X-33 is that nobody's EVER flown an aerospike engine. We know that there is the potential for trouble... theory dictates that in certain mach ranges, it will have inefficencies. Like scramjets, folks THINK that it won't be a problem, but only flight testing is going to tell. And because NASA picked the most experimental design and Lockheed Martin tried to snow-job NASA into believing that they could make some of the experimental things work that bit them in the butt....

Yes - that is funny. But you know what is hilarious? It has been studied! (Well, sort of...)

http://yarchive.net/space/science/g_tolerance.html

The precious quote:

There was the hyper-G work done on chickens, for example, by Arthur Hamilton ("Milt") Smith in the 1970s. Milt Smith was a gravity specialist at the University of California at Davis who wanted to find out what would happen to humans if they lived in greater-than-normal G-forces. Naturally, he experimented on animals, and he decided that the animal that most closely resembled man for this specific purpose was the chicken. Chickens, after all, had a posture similar to man's: they walked upright on two legs, they had two non-load-bearing limbs (the wings), and so on. Anyway, Milt Smith and his assistants took a flock of chickens -- hundreds of them, in fact -- and put them into the two eighteen-foot-long centrifuges in the university's Chronic Acceleration Research Laboratory, as the place was called.

They spun those chickens up to two-and-a-half Gs and let them stay there for a good while. In fact, they left them spinning like that day and night, for three to six months or more at a time. The hens went around and around, they clucked and they cackled and they laid their eggs, and as far as those chickens were concerned that was what ordinary life was like: a steady pull of two-and-a-half Gs. Some of those chickens spent the larger portion of their lifetimes in that goddamn accelerator.

Well, it was easy to predict what would happen. Their bones would get stronger and their muscles would get bigger--because they had all that extra gravity to work against. A total of twenty-three generations of hens was spun around like this and the same thing happened every time. When the accelerator was turned off, out walked . . .GREAT MAMBO CHICKEN!

Yep, there was an Air Force requirement to make a single polar orbit (over Russia, of course), drop a present, and land in one pass. That required steep descent, 1000 mile crossrange (because the Earth turns 1000 miles in one orbit), and a lot of associated headaches.

Scramjets have the problem of not existing. That said, it is not 100% sure that they are the best way to go. (Of course, a lot of this is determined by your definition of the word "best"). For example, you absolutely need rockets once you leave the atmosphere (all sub-escape trajectories that leave the atmosphere re-enter it). So if you have to use rockets anyway, at what point is it better to go straight from mildy supersonic to rocket, skipping the scramjet stage? If you include development costs over the current flight rate, you definately choose rockets. If you amortize the development across launches every few hours, the balance may change...

Sharp egdes on hypersonic vehicles are being looked at again, because of new advanced materials. Personaly, I don't think they will happen - there are cheaper ways to do things like that.

Unfortunately, most of my information comes from the web (Google Groups is a good place to start - although for space in particular I would read http://yarchive.net/space - it is better organized), so I can't really recommend a good book. A Googgle groups search can probably give you one, though.

The parachute trip takes about an hour, as I recall - I think recently someone was seriously considering that as a business angle at one point.

Just to put that into perspective: There was about 23 kg of Pu-238 aboard the Cassini probe. The same amount of caffeine would be in 230,000 12 oz cans of Jolt Cola (or espressos, if you prefer).

the detection of the 10 watt (mostly) non-directional radio transmitter atop the Huygens probe

And according to this page, we're still picking up signals from Voyager 1 and 2 (and recently lost Pioneer) as of 2001, with the distance of Pioneer 1 being almost 12 billion miles as of the time of the article. Most of these problems have transmitters that transmit at around 10 watts.

Whoops....should have been 10 minutes. Sorry about that.

You can see some more info on H2S here: H2S Safety Info.

Also, if you are really interested, just search for "sour gas" or natural gas pipelines. This is a VERY well known concept. So much so that you would be hard pressed to find a single pipeline guy who doesn't know about it. I mean, it's like saying you know cars and then having no idea what a tire is. It's that "big" of a deal in the pipeline business. And the simple reason it's that way is...because it kills people.

PLEASE PLEASE PLEASE do not try to prove me wrong by inhaling 600ppm like the grand-grandparent says. You *will* hurt yourself badly.

You read it once already. Allow me to repeat it at greater length. Silence was copyrighted in 1952. Obviously, silence did not exist before that year. Assuming no further term extensions, silence will be owned by the John Cage foundation until the year 2052, as he died in 1977. You are hereby forbidden, under penalty of law, to copy, distribute, or publicly perform silence without permission of the John Cage foundation for the next 48 years. You may have the right to remain silent when arrested, but exercising that right without proper permission puts you in violation of copyright law. Penalties can be as great as 5 years in prison and $150,000 per offense. Can you honestly tell me that is not absolutely the most utterly ridiculous perversion of copyright law you have ever heard?

So, back to you. How do I "automatically" have rights to stuff you thought up? Simple, you told me what you thought up. What, you can collect money and then erase your idea from my mind? No, I didn't think so. You have it backwards. What gave you the right to dictate what I could do with an idea you shared with me? Without copyright, absolutely nothing. That's the point of Copyright; to give you just enough incentive to share what you know to promote progress. Copyright is about making sure you want to share that great idea with the rest of us. That way, we as a whole can make use of it for the good of mankind. It is not in any way compensation for work of any kind. Allowing you and your descendants to play idea dictator with copyright is expressly against the intention of copyright. If you didn't want to share your ideas with the world, you should have kept them to yourself. If you need further elaboration, I suggest you read this.

Hopefully after reading that you will understand my point more thoroughly. However, my guess is you've already labeled me a whiney p2p pirate who has some sense of entitlement to free stuff and skipped into skim mode. You are the one with the mistaken sense of entitlement. I have presented this argument, at length, a number of times to people like yourself. To date, no one on your side of the argument has attempted to read or understand what I have presented. They simply continue to spout **AA duckspeak.

I am not against copyright. Nothing could be further from the truth. Copyright is extremely useful. Copyright is, after all, what gives the GPL its teeth. Copyright gives me incentive to create software. But I am very much against ridiculous copyright terms, penalties, and restrictions. Those things only serve to destroy the very system you and I live by. Infringement on P2P networks is not a cause for 'tough, new' copyright laws and enforcement. It is the effect of the overly restrictive and oppressive copyright laws we have already. Continuing down the path you so fervently defend is to seek the destruction of copyright in its entirety.

And there I go pulling a John Kerry; describing complex issues in detail when the average joe just wants a sound bite. Well, here's one of those for you too:

• Copyright as we know it today is nothing more than a pyramid scheme.

.
It's worth looking into, others have proposed it before and done preliminary
work - and that was before the last 40 years of materials science!

http://yarchive.net/space/launchers/personal_reent ry.html
.

Actually, space capsules are easily reusable - there were plans to do this with Apollo capsules to cut costs. A Gemini capsule actually was reused, by simply replacing the heat shield. (References)

The thing is, as I mentioned in my previous post, it may be more expensive to operate a cable (think train with an exceptionally long track) than to operate some other method (such as an X-prize like machine). The primary factors in my opinion are that:

1) It takes more than a week to get up there, so your throughput is limited (what if only 1 airplane, or even only 10 airplanes could be flying between Chicago and New York at any one time, and the flight took a week - does that sound like a viable business?)

2) The cable will develop a break approximately every 10 days, and so will be a maintainence nightmare. (See here)

I think that cheaper ways to orbit will be found before these problems are solved. (In fact, I'm working on one right now)

I believe that the technical challenges are quickly being solved, and that the safety issues can likewise be solved. What I believe will kill space elevators are the business issues.

For the space elevator to make sense, it must be the cheapest method of getting into space. Obviously, the incremental cost is probably VERY low, like $1/lb, compared to the cost of rockets at $10,000/lb. However, there are several other costs that I project will make this non-economical:

1. Development / Deployment - new technology (lighter materials) may make this work, indeed this is where most of the work to date has been done.
2. Trip time - it will take a week or more to travel that far. This will at least be a problem for humans.
3. Maintainence - This is the big one. We are building trains to replace aircraft, except the track is VERY long (35,000 km)! This track will need to be constantly repaired (because of meteorite damage, and other damage). On average, there will be a partial structural failure every 10 days, due the unfriendly neighbors in space. (references)

That third problem is a major problem for this being cheaper than even $10,000/lb. Especially mixing in the second problem, which limits how far economies of scale can go. You would have to have repair teams running constantly, and your design margins would need to be extremely robust to survive almost weekly cable cuts.

I wish this would work, but I'm afraid it won't.

"...The only thing in the body that heavy water might affect is osmosis, so I think that is a very unlikely suggestion..."

No Nobel prize. Not even a White Owl. Here's a more knowledgeable view of heavy water toxicity

To quote:

"When body deuterium reaches about 50%, it inhibits mitosis because spindle microtubules won't form (some hydrogen bond effect inhibiting self-polymerization, I think). So all eucaryotic cells are poisoned about about these concentrations, or a little higher (bacteria can survive full deuteration-- they just grow half as fast). The consequences of failure of cell division for an intact animal like a rodent, are somewhat like those of radiation or chemo-- the bone marrow and gut lining cells suffer. Animals die of infection or diarrhea. "

T&K.

Why don't you read some of the reasons why meds are so expensive?

Apologies for the length of this quote from the above link, but I think it's worth reading (Steve Harris MD on medical costs and litigation):

"...You [correspondent] were complaining about the cost of American medical care not long ago. You are clueless as to the connection here. Drugs cost more here. Medicine costs more here. A lawyer costs more here. An artitect costs more here. Each of these things has reasons. Until you step away from medicine and see the big picture, you'll never figure it out...

... And that's not even the worst part. The worst part is what you don't see. The products that are never developed, or developed too late to help people, because everyone is afraid that somebody will get hurt, and sue. In the case of vaccines it got so bad that without DIRECT government intervention to hamstring the civil litigation process, you would not today be able to buy a dose of vaccine in the United States for love or money. The very last couple of makers were getting set to leave the U.S. market and sell only overseas, before the government stepped in and stopped an out of control civil litigation process...

...For less obvious things than vaccines and aircraft, FYI, the government does not step in, and the product you don't know about simply ceases to exist. If you need a lung lavage of fluorocarbon to save your life if you have lung damage from a fire or shock, you're not going to get it. 3M, which makes most of these chemicals, quite deliberately got out of the medical market years ago, after the Dow Corning Silicone suit. So you're out of luck. You won't know why, but that won't change a thing. If your heart valve fails, you'll never know that it might not have, if the suture 3M made for that purpose, in a little tiny subdivision of the company, was still available. But it's not, since a giant company like 3M has deep pockets, and they don't need the medical market liability grief. Now, it's YOUR problem."

T&K.

http://yarchive.net/nuke/coal_radiation.html

The best one: http://www.ornl.gov/info/ornlreview/rev26-34/text/ colmain.html