I read a report about this ages ago. There is some mercury vapour present as it is spun up but an oxide layer soon forms and then the vapour quickly dissipates. The scientists just hang around outside until the mercury vapour level goes down and then they can go in.
The problem with the GNUTELLA protocol is that it it is quite inefficient, and it collapses completely at heavy load.
The GNUTELLA protocol sends one message per search through the entire network upto the horizon.
Eventually when enough people are in the network the individual links collapse under the load and the network falls apart.
Nothing can completely solve this problem, but graceful degradation can certainly be designed for, and the way that the GNUTELLA protocol uses bandwidth can be very much improved, allowing for many more users, but at reduced horizon sizes.
The current protocol wastes bandwidth in atleast one BIG way: it sends many short messages rather than one big one containing the requests.
The reason that that is a waste is that each short message has a fixed sized overhead, at the TCP level. This means the useful percentage of bandwidth is significantly smaller than it might be if large messages were sent.
Therefore it pays to hold off each search request for maybe 1 second before passing all the search requests on to the neighbours- the searching will be maybe 10 seconds slower due to the artificial delay (compared to 2 minutes; also offsetting this is the reduction in bandwidth), but possibly 50-100% as many users can be catered for.
Secondly the behaviour at collapse can be much improved. To implement the above behaviour, each client should keep a list where it keeps requests/replies before forwarding them off to neighbours.
If a request is held onto for too long without having a chance to pass it on then it should get thrown away (giving preference to low hop messages). That means that the horizon self tunes- avoiding collapse and giving better search performance at small network sizes.
Otherwise death of the GNUTELLA net is predicted...
OK. I thought at first you were trolling, but I've come to the conclusion you are just monumentally stupid.
There is a huge difference between Java and Javascript. That 'source code' you are looking at is probably Javascript.
Java code is deployed precompiled in.class files, you can't read the source unless someone gives it to you.
"Want to know why XMMS uses.so files?" - No. I don't care.
"RUNTIME PERFORMANCE! I believe that this should be the be-all end-all factor of programming." - enjoy yourself, with your assembly language programming- moron.
It turns out that with a good compiler it can completely remove the inefficiencies relating to 2 + 2. No objects are needed at the end of the day, because the compiler knows that 2 is an integer. Even if it was 'a + 2' it can write code that checks the type of a and write code that is specific to integers, even before the function is called at all.
Anyway the fastest Smalltalk I knew was actually another language.
Huh? Ok bear with me. There once was a language called Smalltalk. Smalltalk begat Self (Sun prototype based OO language not totally dis-similar to Smalltalk). After they spent a few YEARS optimising Self it ran at about 1/2 the speed of OPTIMISED C, it is harder to optimise than Smalltalk even. And it ran several times faster in fact.
Anyhow, the last release of Self actually supported Smalltalk. At the time it was the fastest Smalltalk ever to the best of my knowledge, but it only ran on one or two types of Sun machines, but the Self project was canned.
Anyway the research for Self has been hugely influential:
Sun invented Oak, changed its name to Java, but the reason they did Java is because underneath the C syntax and the type system it's not a million miles from Smalltalk/Self infact (everything is passed by reference, GC etc. etc.) and has similar optimisation problems.
Ever heard of Transmeta? Well, that is based on Dynamo, which in turn was based on a byte code interpreter written for, you guessed it, Self.
Hotspot? Same thing. Self tech.
Ok. That's the upside. Downside of Self is that it had a nasty tendency to use great gobs of memory. Five years ago or so it wouldn't run in less than 20-60 meg or so and that was a lot, then. More if you had an application, and its speed varied as it recompiled lots of cached code 20 different ways to deal with different types; but once it got going- it was really very FAST. Java has only just passed it efficiency wise.
Oh? Ever wondered why the server seems to be down so often? But then you reload and it is in fact there?
As far as initiating http connections are concerned- the protocol was designed in a regime where packet loss was rare, but the current protocol frequently faces 10-100% packet loss due to congestion -> an equal number of web pages fail to load that percentage of time.
I'm not sure off-hand whether the problem is in the http protocol or TCP or the browser itself. In some ways it doesn't matter; the problem is there, its real, networking books describe it.
If your web server is getting hammered; that usually means you are doing business. If you are doing N times more business, you can probably afford N times more servers... load sharing of web servers isn't exactly rocket science.
Bandwidth in the core network? Don't make me laugh. 6.4 Terabits/second on a single fiber is already demoed, 640Gb/s systems are deployed already. Basically bandwidth is doubling every NINE months and has been for decades. Moores law eat your heart out.
Ok first, 1000x bigger pipe doesn't mean we will be accessing 1000x more web pages. That's the first thing. The user just can't handle that many web pages.
Secondly, at the moment people are making direct independent connections from desktop to the web server. That isn't necessary- it's only necessary to construct a tree of the machines who have/need the info and go to the nearest machine with a copy. That's definitely been used for web pages, but it becomes essential for video on demand, which is presumably what these fat pipes are mostly for.
In any case, the internet has always had congestion problems. And it has some fixes for some congestion problems already:
- slow start (this tries to stop new connections crashing the internet)
- exponential backoff (this tries to share out the bandwidth fairly between connections)
and a few other things: basically if there are 100 people connected they each get 1/100 of the available resources; it doesn't matter if they each have 1 Gb connections- they only get 5kbs if that's their share.
Which isn't to say there aren't problems. One problem on the internet at present is the loss of the messages to open connections for web pages. There is apparently no protocol to check that they make it through- if they don't make it, you just have to retry. For web pages this means the users have to press the reload button, and it messes up caching.
>A segmented elevator cable in earth orbit plus orbit mechanics allows you to get around with only 1/7 of the height in actual cable segments. You coast between cable segments.
Don't know this one. Do you have a URL?
>A tower from the ground several tens of km tall saves you most of the losses that a rocket like the shuttle sees from trajectory inefficiency and atmospheric drag. You simply launch from the top of the tower.
Problem with this is it doesn't help much. (93% of the energy to get to LEO is going sideways; only 7% is altitude.) The cost of the tower would be trillions; and probably very wobbly.
> Existing high strength carbon fiber (1 million psi strength) is sufficient for economically rational space elevators. Carbon nanotubes are strong enough for a 35,000 km space elevator, but they would also make possible ultra-light rockets that would eliminate the cost justification for such a large elevator.
In other words, rockets are actually too cheap for space elevators to every be practical on economic grounds. There was a design for a rocket in the 60s that could launch over 100 tonnes at orders of magnitude lower cost than the current price. Its a little known fact that the fuel needed to get across the atlantic in Concorde is comparable for that to get to low earth orbit (per payload.)
Tethers look very much more promising in the short term.
How thick would the elevator be if we make it out of polycrystalline diamond?
Cos we can grow them to arbitrary shape already (of course theres a small difference between a cm and 38000 kms... but still. Theoretically can we do it already?
No. I don't see the problem. If you set the fitness criteria so that it 'gains maximum altitude' then it may well sprout wings.
Or, if your argument is that the fitness criteria has to be set up to specifically gain maximum altitude, then I contend that building two sets of robots where one has to 'stay away from the other' (i.e. red queen), then in some cases the chased or chasing robots will develop flight (if it is possible with the plastic hardware, sensors and actuators that the program has available.)
Which isn't to say that it will definitely discover flight in a short time period; it almost certainly won't.
Anyway I've studied/played with this stuff too.
Phrases like hill climbing imply a pretty two dimensional fairly smooth evolutionary landscape. The real landscape is usually very fractal very multidimensional, with narrow corridors leading off in different directions- this way to flight, this way to multicellular organisms etc. etc. (But because they are narrow they don't get discovered very much.)
Narrow routes require several mutations to happen together to achieve success. That's rare: a narrow route, and hence evolution is frequently slow.
> the program can't really create something novel
> that the programmer hadn't already thought
> of -- just combinations of preprogrammed
> parts
Oh right, and combinations of preprogrammed parts aren't novel?
Think about houses. Houses are made from bricks (standard size and shape), planks (standard sizes, cut to length), tiles (standard sizes), sheets of standard material a few pipes, the odd mass produced device.
And of course all these standard bits never make up to an original building, and its impossible that a computer program to ever put together standard bits and come up with a unique shape?
And computer programmers are able to work out every combination of these bits, before the program does; even though the program is searching the space of the combinations at a rate of millions per second?
Sorry. No. You're wrong. Troll?
Re:Threat to "secret ballot"?
on
Online Voting?
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· Score: 1
This problem can be mostly fixed if you are allowed to 'spoil your vote' before or after it has been cast. That way, your vote still counts in the following sense: if the difference in votes between the one that won and the next candidate is sufficiently great then a new election has to be called.
However, this only works in situations where people aren't locked up for days before the vote- spoiling your ballot afterwards probably wouldn't be allowed (although that's not a totally stupid idea- it amounts to a vote of no confidence.)
Titan IV is about the same size as a Proton- and at about 3 times the cost if the figures I've managed to dig up are at all accurate. I'm not sure that increased complexity reduces failure rate. Increased complexity usually reduces reliability as a cost of improving performance. The Kistler design certainly appears to be a pretty good one so far. I don't like the look of the reassembly; but other than that it seems spot-on. The Roton design seems to me to be much more elegant, although even there the payload size is a bit small for my liking. Alas, if I only had $151 million... (One million to live off and 150 to give to Rotary Rocket!)
Its pure speculation but it might be the X-33. Its well known that they have had problems with the fuel tank- and its also well known that they don't want to announce anything on it until after the elections...
>Proton: $3,500 / kg * 2.2 =~ $7,700 / lb >Shuttle: $20,000 / kg * 2.2 =~ $44,000 / lb Try: $3,500/kg / 2.2 = $1,590/lb $20,000/kg / 2.2. = $9,090/lb There's 2.2 lbs to the kg not the other way around! You have a point with the orbit- PROTON can lift 20 tonnes to 200 km, but the ISS is at about 200 miles. That will increase the costs of course, and it is significant, but the reduction of costs with volume of launch is still much larger.
>How did you get that 21 ton figure for a Proton's payload capacity? My Aviation Week & Space > Technology Sourcebook says that a single Proton-K launch can deliver 12,100 lbs into a 28.5 > degree transfer orbit. Just a wee bit less than you're dreaming of.
> And where did you get that cost figure!?!? Last I read, the __lowest__ commercial launch cost in > the world (including the Proton or Long March) will give you $10,000 / lb to Low Earth Orbit, with > a Proton launch costing significantly more than the $70 million you're claiming.
Your figures are way off. Way, way, wayyyyyyy off. The space shuttle costs $9,000 / lb and that may be the most expensive vehicle ever! Check out: http://www.ssc.se/ssd/diary001.html. Incidentally the latest module launched for the ISS was close to 20 tons, and that was launched on a Proton.
According to: http://www.russianspace.com/proton.html the LEO launch capability of a PROTON-K is 20.6 tons, PROTON KM is 23.5 tons.
As for melting people down- no I'm not seriously suggesting launching people on a Proton, it's just a plausibility argument. Its not manrated.
Still, theoretically, how much extra weight is a couch and an enlarged nose cone? There'd be more aerodynamic losses, but I'd be surprised if they were that significant. Most of the thrusting is outside the atmosphere anyway. Volume is mostly irrelevant, its mass that counts...
But the real point was purely illustrative. You are taking this way too seriously.
As for talking to politicians. Thanks but no thanks. I'm more tempted to talk to a hotel or a banker. I'm in the UK, the government may not be able to find 1 billion. The US government/NASA can't make money by law so wouldn't go for it.
>No, there is no _inherent_ reason. However, since >a rocket is a big tube 'o propellant which pushes >itself upwards through a controlled explosion
No explosions are involved. Anyway, most failures these days are stupid things like guidance system screwups- software bugs that sort of thing. The point is that all failures are removable with practice, process or redesign changes. There's nothing in the laws of physics that says that 2% of all rockets explode.
>>>So, it costs $350,000 to launch a person to >>>orbit... >>Very roughly, atleast this is the current freight >>cost. >Do you have numbers to back that claim up?
Oh sure. Proton has about the lowest cost at present $60-80 million for 21 tons. Let's take $70 mill. Lets assume an average weight, say 85 kgs and you end up with about 280 people per launch.
In fact that makes $250,000. I think the 350,000 figure allowed for extra launch mass. But it doesn't matter because there are so many other variables- its all rule of thumb.
The thing is though if you go to a launch vehicle supplier and say, Great! I want to launch one a week for the foreseeable future what can you do for me? You may well be able reduce the cost by >50% with economies of scale... right off the bat; you've just grown his business by 1000%; with greater reductions down the road if you can grow your business too.
Of course in practice, you can't herd the people like cattle onto a proton,;-) Plus you'd have to allow for food and air.
The bottom line though is that rockets scale real well. Launching more rockets or bigger rockets reduces the costs massively. The current state of the art is well away from the achievable values.
A real attempt at this would probably have to have a target price of around $150-250,000 for a week. Little or no luggage. Clothing would be provided. Launching say 30 people a week into a space station consisting of a few MIRs connected together. The only questions in my mind is whether the increased launch rate would reduce the costs enough... and whether the launchers can be made reliable enough.
Its definitely doable, but it's getting over the startup hump that's the problem- like most businesses.
The zero gravity swimming pool bit would be rather fun though.
All the energy that goes into a rocket comes from fossil fuels. It doesn't matter whether you burn the fossil fuels in a rocket or in an internal combustion engine, the effect is the same.
Besides, there aren't enough rockets to worry about- you should be far more worried about cars.
Incidentally rockets aren't as inefficient as you might suppose. They have very high thermodynamic efficiency because they run at extreme temperatures. Aeroplanes crossing the atlantic use not dissimilar quantities of fuel. It's only that a lot of rockets use hydrogen fuel that rockets get to be so big. (Hydrogen is many times less dense compared to say, gasoline, for the same energy.)
There's no inherent reason why rockets have a 1 in 100 failure rate. In fact rockets are quite unreliable the first few launches and then improve quite considerably. The problem with launchers at the moment is they haven't launched enough times to get the bugs out. If you only launch a hundred times, you won't be able to prove that you have a reliable vehicle, particularly if one or two of the early launches fail.
>So, it costs $350,000 to launch a person to orbit...
Very roughly, atleast this is the current freight cost. In theory (though probably not in practice), the only thing that needs lifting is an hour of air, and my naked body, and I don't suppose a swimming costume would break the budget;-)
The rest can be up there already if need be, certainly air can be recycled. Food might be grown in space as well. The habitat is a fixed cost. Reducing launch costs also reduce the costs of mining the moon- low earth orbit is closer to the lunar surface than the earth. Once enough infrastructure is launched lunar materials are much cheaper for basic building materials.
Sure whatever happens its going to cost many billions; but there's plenty of projects of that size on the earth.
The deal was dodgy anyway. The size of the space market seems to be partly set by the price- the idea is that reducing the cost of a rocket would just reduce the profit in space. I don't completely understand that, but it makes a certain sense in the short term; if you assume the industries make a fixed percentage of the price, and if the amount launched doesn't depend on the price. Neither is true in detail, or probably general. Probably reducing the price will raise the total value of yearly launches, in the long run.
Anyway it looks like the cartel has broken up. Probably the Ruskies think that they have better rockets based on their long cost-sensitive development history (and they have a point). And they have cheap labour costs.
Maybe the Merkins think that they have more money and can come up with a better design themselves. Maybe, but the cost of rockets seems to increase with greater sophistication rather than decrease.
Personally I'd bet on the Ruskies, but the Merkins might win.
Basically every time the space shuttle launches for the same cost the Russians could have launched about 6 times. That's nutty but true.
Everyone's probably heard the story about the space pen- the Americans needed something that can write in zero-g. They spent a million dollars developing a pen that can write upside down, underwater and even in zero-g. The russians used pencils. That sums up the difference in principle between the two approaches.
Anyway think about this. The Russian proton launcher if it was man rated (it isn't); it could launch people for around $350,000 per person. If there is competition in this market; this price can fall by 4 or more, easily. 10x is harder. But there are credible designs that reduce it by a 100x.
Would you pay $3500 for a trip to space? I would...
If you check out fantastic voyage they discuss a design for a plasma based solar sail, that they calculate might make 80000km/s i.e. solar system escape velocity.
It's based on making a huge (30km across) plasma which weighs basically nothing and using that to trap solar wind and providing a low, but very significant force- much more than ion drive but lasting a similiar period.
Anyway one of the main problems are that the hot plasma tends to melt the outside of the space craft. Perhaps a cold plasma might be better? Anyway check out the link it's cool space tech!
Actually in a funny, but accurate sense; they are less advanced. And that's why they're cheap. Big dumb boosters are cheaper than clever. There is a big dump booster design that could lift hundreds of tons into orbit for literally two orders of magnitude less than even the proton. Nobody has the money to build it right now though- and it would reduce the launch market size for several years, until demand catches up again. Imagine a ticket to orbit for $10,000 or less...
Slashdot Mirror
I read a report about this ages ago. There is some mercury vapour present as it is spun up but an oxide layer soon forms and then the vapour quickly dissipates. The scientists just hang around outside until the mercury vapour level goes down and then they can go in.
The problem with the GNUTELLA protocol is that it it is quite inefficient, and it collapses completely at heavy load.
The GNUTELLA protocol sends one message per search through the entire network upto the horizon.
Eventually when enough people are in the network the individual links collapse under the load and the network falls apart.
Nothing can completely solve this problem, but graceful degradation can certainly be designed for, and the way that the GNUTELLA protocol uses bandwidth can be very much improved, allowing for many more users, but at reduced horizon sizes.
The current protocol wastes bandwidth in atleast one BIG way: it sends many short messages rather than one big one containing the requests.
The reason that that is a waste is that each short message has a fixed sized overhead, at the TCP level. This means the useful percentage of bandwidth is significantly smaller than it might be if large messages were sent.
Therefore it pays to hold off each search request for maybe 1 second before passing all the search requests on to the neighbours- the searching will be maybe 10 seconds slower due to the artificial delay (compared to 2 minutes; also offsetting this is the reduction in bandwidth), but possibly 50-100% as many users can be catered for.
Secondly the behaviour at collapse can be much improved. To implement the above behaviour, each client should keep a list where it keeps requests/replies before forwarding them off to neighbours.
If a request is held onto for too long without having a chance to pass it on then it should get thrown away (giving preference to low hop messages). That means that the horizon self tunes- avoiding collapse and giving better search performance at small network sizes.
Otherwise death of the GNUTELLA net is predicted...
OK. I thought at first you were trolling, but I've come to the conclusion you are just monumentally stupid. There is a huge difference between Java and Javascript. That 'source code' you are looking at is probably Javascript. Java code is deployed precompiled in .class files, you can't read the source unless someone gives it to you.
"Want to know why XMMS uses .so files?" - No. I don't care.
"RUNTIME PERFORMANCE! I believe that this should be the be-all end-all factor of programming." - enjoy yourself, with your assembly language programming- moron.
It turns out that with a good compiler it can completely remove the inefficiencies relating to 2 + 2. No objects are needed at the end of the day, because the compiler knows that 2 is an integer. Even if it was 'a + 2' it can write code that checks the type of a and write code that is specific to integers, even before the function is called at all.
Anyway the fastest Smalltalk I knew was actually another language.
Huh? Ok bear with me. There once was a language called Smalltalk. Smalltalk begat Self (Sun prototype based OO language not totally dis-similar to Smalltalk). After they spent a few YEARS optimising Self it ran at about 1/2 the speed of OPTIMISED C, it is harder to optimise than Smalltalk even. And it ran several times faster in fact.
Anyhow, the last release of Self actually supported Smalltalk. At the time it was the fastest Smalltalk ever to the best of my knowledge, but it only ran on one or two types of Sun machines, but the Self project was canned.
Anyway the research for Self has been hugely influential:
Sun invented Oak, changed its name to Java, but the reason they did Java is because underneath the C syntax and the type system it's not a million miles from Smalltalk/Self infact (everything is passed by reference, GC etc. etc.) and has similar optimisation problems.
Ever heard of Transmeta? Well, that is based on Dynamo, which in turn was based on a byte code interpreter written for, you guessed it, Self.
Hotspot? Same thing. Self tech.
Ok. That's the upside. Downside of Self is that it had a nasty tendency to use great gobs of memory. Five years ago or so it wouldn't run in less than 20-60 meg or so and that was a lot, then. More if you had an application, and its speed varied as it recompiled lots of cached code 20 different ways to deal with different types; but once it got going- it was really very FAST. Java has only just passed it efficiency wise.
As far as initiating http connections are concerned- the protocol was designed in a regime where packet loss was rare, but the current protocol frequently faces 10-100% packet loss due to congestion -> an equal number of web pages fail to load that percentage of time.
I'm not sure off-hand whether the problem is in the http protocol or TCP or the browser itself. In some ways it doesn't matter; the problem is there, its real, networking books describe it.
If your web server is getting hammered; that usually means you are doing business. If you are doing N times more business, you can probably afford N times more servers... load sharing of web servers isn't exactly rocket science. Bandwidth in the core network? Don't make me laugh. 6.4 Terabits/second on a single fiber is already demoed, 640Gb/s systems are deployed already. Basically bandwidth is doubling every NINE months and has been for decades. Moores law eat your heart out.
Ok first, 1000x bigger pipe doesn't mean we will be accessing 1000x more web pages. That's the first thing. The user just can't handle that many web pages.
Secondly, at the moment people are making direct independent connections from desktop to the web server. That isn't necessary- it's only necessary to construct a tree of the machines who have/need the info and go to the nearest machine with a copy. That's definitely been used for web pages, but it becomes essential for video on demand, which is presumably what these fat pipes are mostly for.
In any case, the internet has always had congestion problems. And it has some fixes for some congestion problems already:
- slow start (this tries to stop new connections crashing the internet)
- exponential backoff (this tries to share out the bandwidth fairly between connections)
and a few other things: basically if there are 100 people connected they each get 1/100 of the available resources; it doesn't matter if they each have 1 Gb connections- they only get 5kbs if that's their share.
Which isn't to say there aren't problems. One problem on the internet at present is the loss of the messages to open connections for web pages. There is apparently no protocol to check that they make it through- if they don't make it, you just have to retry. For web pages this means the users have to press the reload button, and it messes up caching.
>A segmented elevator cable in earth orbit plus orbit mechanics allows you to get around with only 1/7 of the height in actual cable segments. You coast between cable segments.
Don't know this one. Do you have a URL?
>A tower from the ground several tens of km tall saves you most of the losses that a rocket like the shuttle sees from trajectory inefficiency and atmospheric drag. You simply launch from the top of the tower.
Problem with this is it doesn't help much. (93% of the energy to get to LEO is going sideways; only 7% is altitude.) The cost of the tower would be trillions; and probably very wobbly.
> Existing high strength carbon fiber (1 million psi strength) is sufficient for economically rational space elevators. Carbon nanotubes are strong enough for a 35,000 km space elevator, but they would also make possible ultra-light rockets that would eliminate the cost justification for such a large elevator.
In other words, rockets are actually too cheap for space elevators to every be practical on economic grounds. There was a design for a rocket in the 60s that could launch over 100 tonnes at orders of magnitude lower cost than the current price. Its a little known fact that the fuel needed to get across the atlantic in Concorde is comparable for that to get to low earth orbit (per payload.)
Tethers look very much more promising in the short term.
How thick would the elevator be if we make it out of polycrystalline diamond?
Cos we can grow them to arbitrary shape already (of course theres a small difference between a cm and 38000 kms... but still. Theoretically can we do it already?
Sure.
You'll understand when you're older. Now go and play with your toys!
In theory there is no difference between theory and practice. But in practice there is.
No. I don't see the problem. If you set the fitness criteria so that it 'gains maximum altitude' then it may well sprout wings.
Or, if your argument is that the fitness criteria has to be set up to specifically gain maximum altitude, then I contend that building two sets of robots where one has to 'stay away from the other' (i.e. red queen), then in some cases the chased or chasing robots will develop flight (if it is possible with the plastic hardware, sensors and actuators that the program has available.)
Which isn't to say that it will definitely discover flight in a short time period; it almost certainly won't.
Anyway I've studied/played with this stuff too.
Phrases like hill climbing imply a pretty two dimensional fairly smooth evolutionary landscape. The real landscape is usually very fractal very multidimensional, with narrow corridors leading off in different directions- this way to flight, this way to multicellular organisms etc. etc. (But because they are narrow they don't get discovered very much.)
Narrow routes require several mutations to happen together to achieve success. That's rare: a narrow route, and hence evolution is frequently slow.
> the program can't really create something novel
> that the programmer hadn't already thought
> of -- just combinations of preprogrammed
> parts
Oh right, and combinations of preprogrammed parts aren't novel?
Think about houses. Houses are made from bricks (standard size and shape), planks (standard sizes, cut to length), tiles (standard sizes), sheets of standard material a few pipes, the odd mass produced device.
And of course all these standard bits never make up to an original building, and its impossible that a computer program to ever put together standard bits and come up with a unique shape?
And computer programmers are able to work out every combination of these bits, before the program does; even though the program is searching the space of the combinations at a rate of millions per second?
Sorry. No. You're wrong. Troll?
However, this only works in situations where people aren't locked up for days before the vote- spoiling your ballot afterwards probably wouldn't be allowed (although that's not a totally stupid idea- it amounts to a vote of no confidence.)
Titan IV is about the same size as a Proton- and at about 3 times the cost if the figures I've managed to dig up are at all accurate. I'm not sure that increased complexity reduces failure rate. Increased complexity usually reduces reliability as a cost of improving performance. The Kistler design certainly appears to be a pretty good one so far. I don't like the look of the reassembly; but other than that it seems spot-on. The Roton design seems to me to be much more elegant, although even there the payload size is a bit small for my liking. Alas, if I only had $151 million... (One million to live off and 150 to give to Rotary Rocket!)
>Proton: $3,500 / kg * 2.2 =~ $7,700 / lb >Shuttle: $20,000 / kg * 2.2 =~ $44,000 / lb Try: $3,500 /kg / 2.2 = $1,590 /lb $20,000 /kg / 2.2. = $9,090 /lb There's 2.2 lbs to the kg not the other way around! You have a point with the orbit- PROTON can lift 20 tonnes to 200 km, but the ISS is at about 200 miles. That will increase the costs of course, and it is significant, but the reduction of costs with volume of launch is still much larger.
>How did you get that 21 ton figure for a Proton's payload capacity? My Aviation Week & Space
> Technology Sourcebook says that a single Proton-K launch can deliver 12,100 lbs into a 28.5
> degree transfer orbit. Just a wee bit less than you're dreaming of.
> And where did you get that cost figure!?!? Last I read, the __lowest__ commercial launch cost in
> the world (including the Proton or Long March) will give you $10,000 / lb to Low Earth Orbit, with
> a Proton launch costing significantly more than the $70 million you're claiming.
Your figures are way off. Way, way, wayyyyyyy off. The space shuttle costs $9,000 / lb and that may be the most expensive vehicle ever! Check out: http://www.ssc.se/ssd/diary001.html. Incidentally the latest module launched for the ISS was close to 20 tons, and that was launched on a Proton.
According to: http://www.russianspace.com/proton.html the LEO launch capability of a PROTON-K is 20.6 tons, PROTON KM is 23.5 tons.
As for melting people down- no I'm not seriously suggesting launching people on a Proton, it's just a plausibility argument. Its not manrated.
Still, theoretically, how much extra weight is a couch and an enlarged nose cone? There'd be more aerodynamic losses, but I'd be surprised if they were that significant. Most of the thrusting is outside the atmosphere anyway. Volume is mostly irrelevant, its mass that counts...
But the real point was purely illustrative. You are taking this way too seriously.
As for talking to politicians. Thanks but no thanks. I'm more tempted to talk to a hotel or a banker. I'm in the UK, the government may not be able to find 1 billion. The US government/NASA can't make money by law so wouldn't go for it.
>No, there is no _inherent_ reason. However, since
...
;-) Plus you'd have to allow for food and air.
>a rocket is a big tube 'o propellant which pushes
>itself upwards through a controlled explosion
No explosions are involved. Anyway, most failures these days are stupid things like guidance system screwups- software bugs that sort of thing. The point is that all failures are removable with practice, process or redesign changes. There's nothing in the laws of physics that says that 2% of all rockets explode.
>>>So, it costs $350,000 to launch a person to
>>>orbit
>>Very roughly, atleast this is the current freight
>>cost.
>Do you have numbers to back that claim up?
Oh sure. Proton has about the lowest cost at present $60-80 million for 21 tons. Let's take $70 mill. Lets assume an average weight, say 85 kgs and you end up with about 280 people per launch.
In fact that makes $250,000. I think the 350,000 figure allowed for extra launch mass. But it doesn't matter because there are so many other variables- its all rule of thumb.
The thing is though if you go to a launch vehicle supplier and say, Great! I want to launch one a week for the foreseeable future what can you do for me? You may well be able reduce the cost by >50% with economies of scale... right off the bat; you've just grown his business by 1000%; with greater reductions down the road if you can grow your business too.
Of course in practice, you can't herd the people like cattle onto a proton,
The bottom line though is that rockets scale real well. Launching more rockets or bigger rockets reduces the costs massively. The current state of the art is well away from the achievable values.
A real attempt at this would probably have to have a target price of around $150-250,000 for a week. Little or no luggage. Clothing would be provided. Launching say 30 people a week into a space station consisting of a few MIRs connected together. The only questions in my mind is whether the increased launch rate would reduce the costs enough... and whether the launchers can be made reliable enough.
Its definitely doable, but it's getting over the startup hump that's the problem- like most businesses.
The zero gravity swimming pool bit would be rather fun though.
Besides, there aren't enough rockets to worry about- you should be far more worried about cars.
Incidentally rockets aren't as inefficient as you might suppose. They have very high thermodynamic efficiency because they run at extreme temperatures. Aeroplanes crossing the atlantic use not dissimilar quantities of fuel. It's only that a lot of rockets use hydrogen fuel that rockets get to be so big. (Hydrogen is many times less dense compared to say, gasoline, for the same energy.)
>So, it costs $350,000 to launch a person to orbit ...
Very roughly, atleast this is the current freight cost. In theory (though probably not in practice), the only thing that needs lifting is an hour of air, and my naked body, and I don't suppose a swimming costume would break the budget ;-)
The rest can be up there already if need be, certainly air can be recycled. Food might be grown in space as well. The habitat is a fixed cost. Reducing launch costs also reduce the costs of mining the moon- low earth orbit is closer to the lunar surface than the earth. Once enough infrastructure is launched lunar materials are much cheaper for basic building materials.
Sure whatever happens its going to cost many billions; but there's plenty of projects of that size on the earth.
The deal was dodgy anyway. The size of the space market seems to be partly set by the price- the idea is that reducing the cost of a rocket would just reduce the profit in space. I don't completely understand that, but it makes a certain sense in the short term; if you assume the industries make a fixed percentage of the price, and if the amount launched doesn't depend on the price. Neither is true in detail, or probably general. Probably reducing the price will raise the total value of yearly launches, in the long run.
Anyway it looks like the cartel has broken up. Probably the Ruskies think that they have better rockets based on their long cost-sensitive development history (and they have a point). And they have cheap labour costs.
Maybe the Merkins think that they have more money and can come up with a better design themselves. Maybe, but the cost of rockets seems to increase with greater sophistication rather than decrease.
Personally I'd bet on the Ruskies, but the Merkins might win.
Basically every time the space shuttle launches for the same cost the Russians could have launched about 6 times. That's nutty but true.
Everyone's probably heard the story about the space pen- the Americans needed something that can write in zero-g. They spent a million dollars developing a pen that can write upside down, underwater and even in zero-g. The russians used pencils. That sums up the difference in principle between the two approaches.
Anyway think about this. The Russian proton launcher if it was man rated (it isn't); it could launch people for around $350,000 per person. If there is competition in this market; this price can fall by 4 or more, easily. 10x is harder. But there are credible designs that reduce it by a 100x.
Would you pay $3500 for a trip to space? I would...
It's based on making a huge (30km across) plasma which weighs basically nothing and using that to trap solar wind and providing a low, but very significant force- much more than ion drive but lasting a similiar period.
Anyway one of the main problems are that the hot plasma tends to melt the outside of the space craft. Perhaps a cold plasma might be better? Anyway check out the link it's cool space tech!
Actually in a funny, but accurate sense; they are less advanced. And that's why they're cheap. Big dumb boosters are cheaper than clever. There is a big dump booster design that could lift hundreds of tons into orbit for literally two orders of magnitude less than even the proton. Nobody has the money to build it right now though- and it would reduce the launch market size for several years, until demand catches up again. Imagine a ticket to orbit for $10,000 or less...