Before we think about new launch technologies, we need to understand why the present ones are so expensive. A 1960s Saturn_V put about 100,000 Kilos in orbit while using about 2 million liters of RP-1 (kerosene), that means in pure fuel costs, a launch would be about $20/Kilogram. The real launch costs for are around 1000X higher.
Energy costs are NOT the reason space is so expensive. It is expensive because it uses a lot of unique, high technology equipment in a very regulated and bureaucratic environment. Any future technology (like a space elevator) would be expected to have similar cost increases.
In any case, nuclear is probably out for earth lift-off. Space elevators require materials that don't exist yet in large quantity - and when they do they would also reduce the cost of conventional launchers. Rail guns / hydrogen guns, (and of course space elevators) are VERY large and expensive -the capital costs are probably too high to ever be practical. Burning kerosene and oxygen works.
Have you seen an numbers on GA safety that look good? Commercial aviation is very safe, but the equipment, operating conditions and pilot training are very different from GA.
I've heard the clam of GA safety many times, but (despite trying), I can't support the claim from the NTSB data.
Certainly flying carefully reduces your risk - but so does driving carefully. I'm convinced that I am safer driving than flying, with equal care to each.
Most of the pilots I know are very safety minded, much more so than drivers. Even so, statistically GA aircraft are more dangerous than cars - similar to motorcycles.
That's OK - I'm willing to accept the risk when I fly, but I belive it is a real increased risk.
I think the problem is that aviation is just a lot less forgiving than driving. In a car you are never more than a few seconds from safety by decelerating and pulling off the road. In an aircraft you may be in weather or over hostile terrain, with no escape.
It is common for pilots to claim that flying is safer than driving, but much as I would like it to be true, I've never seen statistics to support it.
You can adjust your flying to be safer - no night, no over-water, no mountains, good weather, etc, but doing so drastically reduces the usefulness of the airplane.
Good maintenance helps, but even a well maintained engine can fail without warning.
Light aircraft are considerably more dangerous than cars per mile flown. Around 1 fatality / 100,000 hours (or 1 per 15 million passenger miles). Cars are about 1/200 million passenger miles (NTSB statistics).
I don't see any reason to thing the jet pack would be safer than a general aviation aircraft, and it would probably be a lot more dangerous.
Well you might be able to move it around if you stood on a beefed up Segway
Seriously though, the problem with jet packs is that you need a low exhaust velocity to get high thrust with reasonable fuel consumption. (Force=M* V, Power =.5 M*V^2 - M is mass flow rate, F/P ~ 1/V). That means big fans / propellers, and pretty soon you are re-inventing the helicopter or airplane.
I think "intellectual property" is very different than physical property. The classic difference is that if I give you my IP, I still have it.
I also think the IP needs some protection - some types of IP are very expensive to produce. I don't think in needs the SAME protection as physical property.
I don't have a good idea of how to manage intellectual property - I hope someone smarter than me will think of something. What we have now seems to work very badly.
It often takes resources in addition to manpower to invent things. If you are developing new software, all you need is a couple of thousand dollars in computer hardware. If you are developing a more efficient turbine blade design, or a process to make inexpensive biodegradable drinking glasses you may need to spend a lot on hardware.
If you spend a lot developing something, I think you should expect some return.
Do you really see no value in patents? It seems to me that as a society that we want to reward people who invent things. If we reward people for inventing things, it seems logical to punish people who lie about inventing things (eg false patent claims).
Certainly one can argue that the way we implement this is badly broken ( I think it is), but the basic idea seems sound.
I saw a long talk on the sad history of the supercollider some years ago. My take is that the basic budget increase was moderate (~25%), and that the apparent budget increase was much larger as changes were made to how the budget was described (escalation, whether the detector was included, whether other site facilities were included, etc).
The conclusion of the talk was that the supercollider was basically a cold-war project that could no longer be supported as the war died away. Not that it was a military project, but that it was part of the "everything the Soviets do, we can do better" cold war.
In general I'd like to see a better way to fund long term projects so that they can't be canceled as the political situation changes.
Where rather than paying about $10B for a giant accelerator we paid something like $3B for a useless hole in the ground. Spending billions of dollars on a marginal project may not be a great idea, but its a LOT better than spending billions and getting nothing.
I still need to fly all over the world just to go to meetings. A couple of years ago we did some tests of diagnosing accelerator hardware remotely - it took 8 hours to fix a problem that would have taken 10 minutes in person. Until we have effective tele-presence technology on earth I think using it on the moon is a bit optimistic.
Also the time delay will make a avatar-like experience impossible - you couldn't even stand without falling with that long a delay between senses and muscles. Might as well use mars-rover like robots.
Another version (Sorry, don't know if it was from Einstein or from the Meisner Thorne Wheeler book) is that time is chosen to make physics look simple. If I plot the position of an object without any forces acting on it, I can choose time to be such that its position is a linear function of time. Since clocks are based on mechanics, this pretty directly turns into time is what a clock measures.
Once you go beyond that sort of description you need to tread carefully to avoid turning your physics into philosophy. For it to be physics it needs to predict measurable quantities. The original article meets this definition if it can make definite predictions - I couldn't tell for sure from the interview.
Well I did a test. I played the test tracks for my wife (who listens to a lot of classical music and who didn't know the source of this music). Within a minute she said "It sounds like someone wrote a computer music-generation program and it isn't very good yet".
If the LHC ramps up to full energy and luminosity over the next 10 years, it will still be a success despite a 1 year setback. If it spends the next 10 years with a continuing series of problems and shutdowns, and never gets near full performance, it will have been a failure.
Yes - that is a very serious problem. Superconducting magnet systems are designed to shunt the quench energy through some sort of dissipating resistor, but it is a very tricky business. Basically you switch a resistor in series with the SC coil. Sound easy until you think about 10,000 Amps and megajoules of stored energy.
Well if you want to explore new physics, almost by definition you can't be absolutely sure of what will happen. Present theories do not predict that the LHC can produce a macroscopic black hole, but of course can't rule it out with 100% certainty. The only way to be absolutely certain is to not do anything new. Its similar to deciding not to produce a faster network switch because the internet might become a vengeful hyper-intelligent AI and kill us all. You can't prove it won't happen.
BTW: the black holes the LHC might (under existing physics) produce are not capable of absorbing other matter and for practical purposes are just a different type of sub-atomic particle.
In a way the LHC may be the last project of the grand old empire. It may be scaled down from the SSC, but it is still by many measures the largest and most complex machine ever created - designed to understand the most basic physics. 30 years ago you wouldn't have needed to ask what it was for, any more than you would have wondered why were were spending money to go to the moon, or to send spacecraft to Jupiter and Saturn.
With the end of the cold war we no longer feel the need to prove our superiority by building ever bigger and more impressive projects. This has left us without a clear goal.
------ Future generations will draw an arbitrary line and say "this is when the civilization fell".
Compromise is critical part of engineering - one of the reasons that "no compromise engineering" adverts are so silly. You can always make something better if you are willing to spend more money. You can improve one parameter if you are willing to give up on another. For example airliners are designed with something like a 1.5X safety factor on strength (above maximum loads). If the safety factor was 2X, probably a couple of in-flight break-ups would have been avoided, but the overall cost of air travel would increase dramatically.
If Apollo had a higher safety factor, 3 astronauts would not have died - and we might never have gone to the moon. One of NASA's difficulties these days is that people are demanding higher safety, and that makes space more difficult and expensive.
In hind sight it is easy to see where the safety factor should have been increased, but that isn't fair. You don't know in advance which part will fail, so you try to design critical systems to similar safety factors.
Sometimes you get it wrong - but even that is a trade-off in engineering costs. Additional engineering reviews take time and money - and may eliminate the project, or reduce its capabilities.
I am aware of another large accelerator project - the Next Linear Collider. Unless you are in the field you probably haven't heard of it. That's because the design was too expensive and it will never be built.
The interconnects are rather complex superconducting devices, not simple electronic connections. It certainly would have been possible to design them with a higher safety factor, but that would have increased the cost. If that approach had been taken with all of the critical components for the machine, the overall cost would have been significantly higher. Unfortunately for a large cutting edge project on a tight budget, you need to take some technical risks. Over the next 10 years we will see if they put a reasonable safety factor on the overall design.
I think this illustrates one of NASA's biggest problems. Different people have different and incompatible ideas of what its mission should be. They work on projects that take more than a decade, so changing missions with changing administrations can result in nothing getting done. Should they do manned space? Environmental monitoring? Aerospace R+D? Deep space science? These all require very different infrastructure.
My personal vote is for manned space and deep space science because I don't think any other (US) organization is likely to do these, but there are many other reasonable options. As a country we need to decide, and stick with that decision.
Anti lock brakes must allow some sort of electronic control unit to disable the breaking action when the tires loose traction. Is there a plausible scenario where a failure of that unit could be coupled to a failure of an electronic engine control?
To me space is a goal, not a means. We shouldn't do space because we need what is out there - we don't. We can create a happy stable (read static) society here on earth. We should do space because we WANT what is out there, because it would be a tragedy if we were too lazy to ever leave out planet.
When the guys on the ships wave at the guys on the shore, you want to be the guys on the ships.
There are lots of "diceless" systems - basically rock-scissors-paper variants.
I have this wonderful image of a 6'2, 300lb tattooed muscular prisoner whining about whether his 58th level paladin's holy sword being destroyed by enchanted rust-monsters.
I actually think games like D&D are a very good thing for prisoners - it teaches a variety of new ways to interact with people and non-violent ways to let off aggression.
There are good and bad things of all types in movies, I don't see why the UIs should be any different. Most are pretty poor, but there may be clever ideas here and there that could find their way into a real UI.
Personally I like large monitors for some types of control. The SLAC accelerator control room contains a large number of large monitors (covering most of the available space now. That way the operators can glance around the room and quickly get status on a large number of systems. This seems to be more efficient than selecting through display windows or having automatic alarms raise windows (both of which we've tried as well). For special purpose systems large monitors are cheaper (only a few thousand $), than custom software (which could run millions of $).
What surprises me is that the treatment was continued after the system appeared to be misbehaving. I work with a large (the world's largest actually), linear accelerator. We do not do medical work, but do have various radiation safety systems. When a safety system behaves in an unexpected fashion, the operators do no just "try again". The affected part of the system is shut down and the problem is investigated by experts. I have observed this in person and it appears to me that the operations staff takes this situation seriously and I believe would never proceed with beam operations if the safety systems we not operating as expected.
I would think that medical equipment would operate under the same standards. Operators and doctors should be trained to stop work any time the system does not respond as expected. (This is very simple: if the machine is not behaving exactly as specified in the operating procedures, STOP and call an expert). The "expert" is then held responsible for the correct functioning of the machine. If it fails after he gives it the ok - the line of responsibility is very clear.
I understand that there are serious consequences to shutting down a treatment center, but we sometimes shut down a billion-dollar accelerator center when there are questions about safety equipment. We of course keep experts on call so that any issues can be resolved quickly.
Disclaimer - I work at SLAC and represent what I have observed to the best of my ability, but I am not an official spokesman for the lab and am not directly involved in safety oversight.
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Before we think about new launch technologies, we need to understand why the present ones are so expensive. A 1960s Saturn_V put about 100,000 Kilos in orbit while using about 2 million liters of RP-1 (kerosene), that means in pure fuel costs, a launch would be about $20/Kilogram. The real launch costs for are around 1000X higher.
Energy costs are NOT the reason space is so expensive. It is expensive because it uses a lot of unique, high technology equipment in a very regulated and bureaucratic environment. Any future technology (like a space elevator) would be expected to have similar cost increases.
In any case, nuclear is probably out for earth lift-off. Space elevators require materials that don't exist yet in large quantity - and when they do they would also reduce the cost of conventional launchers. Rail guns / hydrogen guns, (and of course space elevators) are VERY large and expensive -the capital costs are probably too high to ever be practical. Burning kerosene and oxygen works.
Have you seen an numbers on GA safety that look good? Commercial aviation is very safe, but the equipment, operating conditions and pilot training are very different from GA.
I've heard the clam of GA safety many times, but (despite trying), I can't support the claim from the NTSB data.
Certainly flying carefully reduces your risk - but so does driving carefully. I'm convinced that I am safer driving than flying, with equal care to each.
Most of the pilots I know are very safety minded, much more so than drivers. Even so, statistically GA aircraft are more dangerous than cars - similar to motorcycles.
That's OK - I'm willing to accept the risk when I fly, but I belive it is a real increased risk.
I think the problem is that aviation is just a lot less forgiving than driving. In a car you are never more than a few seconds from safety by decelerating and pulling off the road. In an aircraft you may be in weather or over hostile terrain, with no escape.
It is common for pilots to claim that flying is safer than driving, but much as I would like it to be true, I've never seen statistics to support it.
You can adjust your flying to be safer - no night, no over-water, no mountains, good weather, etc, but doing so drastically reduces the usefulness of the airplane.
Good maintenance helps, but even a well maintained engine can fail without warning.
Light aircraft are considerably more dangerous than cars per mile flown. Around 1 fatality / 100,000 hours (or 1 per 15 million passenger miles). Cars are about 1/200 million passenger miles (NTSB statistics).
I don't see any reason to thing the jet pack would be safer than a general aviation aircraft, and it would probably be a lot more dangerous.
Well you might be able to move it around if you stood on a beefed up Segway
Seriously though, the problem with jet packs is that you need a low exhaust velocity to get high thrust with reasonable fuel consumption. (Force=M* V, Power = .5 M*V^2 - M is mass flow rate, F/P ~ 1/V). That means big fans / propellers, and pretty soon you are re-inventing the helicopter or airplane.
I think "intellectual property" is very different than physical property. The classic difference is that if I give you my IP, I still have it.
I also think the IP needs some protection - some types of IP are very expensive to produce. I don't think in needs the SAME protection as physical property.
I don't have a good idea of how to manage intellectual property - I hope someone smarter than me will think of something. What we have now seems to work very badly.
It often takes resources in addition to manpower to invent things. If you are developing new software, all you need is a couple of thousand dollars in computer hardware. If you are developing a more efficient turbine blade design, or a process to make inexpensive biodegradable drinking glasses you may need to spend a lot on hardware.
If you spend a lot developing something, I think you should expect some return.
Do you really see no value in patents? It seems to me that as a society that we want to reward people who invent things. If we reward people for inventing things, it seems logical to punish people who lie about inventing things (eg false patent claims).
Certainly one can argue that the way we implement this is badly broken ( I think it is), but the basic idea seems sound.
I saw a long talk on the sad history of the supercollider some years ago. My take is that the basic budget increase was moderate (~25%), and that the apparent budget increase was much larger as changes were made to how the budget was described (escalation, whether the detector was included, whether other site facilities were included, etc).
The conclusion of the talk was that the supercollider was basically a cold-war project that could no longer be supported as the war died away. Not that it was a military project, but that it was part of the "everything the Soviets do, we can do better" cold war.
In general I'd like to see a better way to fund long term projects so that they can't be canceled as the political situation changes.
Where rather than paying about $10B for a giant accelerator we paid something like $3B for a useless hole in the ground. Spending billions of dollars on a marginal project may not be a great idea, but its a LOT better than spending billions and getting nothing.
I still need to fly all over the world just to go to meetings. A couple of years ago we did some tests of diagnosing accelerator hardware remotely - it took 8 hours to fix a problem that would have taken 10 minutes in person. Until we have effective tele-presence technology on earth I think using it on the moon is a bit optimistic.
Also the time delay will make a avatar-like experience impossible - you couldn't even stand without falling with that long a delay between senses and muscles. Might as well use mars-rover like robots.
Another version (Sorry, don't know if it was from Einstein or from the Meisner Thorne Wheeler book) is that time is chosen to make physics look simple. If I plot the position of an object without any forces acting on it, I can choose time to be such that its position is a linear function of time. Since clocks are based on mechanics, this pretty directly turns into time is what a clock measures.
Once you go beyond that sort of description you need to tread carefully to avoid turning your physics into philosophy. For it to be physics it needs to predict measurable quantities. The original article meets this definition if it can make definite predictions - I couldn't tell for sure from the interview.
Well I did a test. I played the test tracks for my wife (who listens to a lot of classical music and who didn't know the source of this music). Within a minute she said "It sounds like someone wrote a computer music-generation program and it isn't very good yet".
If the LHC ramps up to full energy and luminosity over the next 10 years, it will still be a success despite a 1 year setback. If it spends the next 10 years with a continuing series of problems and shutdowns, and never gets near full performance, it will have been a failure.
Yes - that is a very serious problem. Superconducting magnet systems are designed to shunt the quench energy through some sort of dissipating resistor, but it is a very tricky business. Basically you switch a resistor in series with the SC coil. Sound easy until you think about 10,000 Amps and megajoules of stored energy.
Well if you want to explore new physics, almost by definition you can't be absolutely sure of what will happen. Present theories do not predict that the LHC can produce a macroscopic black hole, but of course can't rule it out with 100% certainty. The only way to be absolutely certain is to not do anything new. Its similar to deciding not to produce a faster network switch because the internet might become a vengeful hyper-intelligent AI and kill us all. You can't prove it won't happen.
BTW: the black holes the LHC might (under existing physics) produce are not capable of absorbing other matter and for practical purposes are just a different type of sub-atomic particle.
In a way the LHC may be the last project of the grand old empire. It may be scaled down from the SSC, but it is still by many measures the largest and most complex machine ever created - designed to understand the most basic physics. 30 years ago you wouldn't have needed to ask what it was for, any more than you would have wondered why were were spending money to go to the moon, or to send spacecraft to Jupiter and Saturn.
With the end of the cold war we no longer feel the need to prove our superiority by building ever bigger and more impressive projects. This has left us without a clear goal.
------
Future generations will draw an arbitrary line and say "this is when the civilization fell".
Compromise is critical part of engineering - one of the reasons that "no compromise engineering" adverts are so silly. You can always make something better if you are willing to spend more money. You can improve one parameter if you are willing to give up on another. For example airliners are designed with something like a 1.5X safety factor on strength (above maximum loads). If the safety factor was 2X, probably a couple of in-flight break-ups would have been avoided, but the overall cost of air travel would increase dramatically.
If Apollo had a higher safety factor, 3 astronauts would not have died - and we might never have gone to the moon. One of NASA's difficulties these days is that people are demanding higher safety, and that makes space more difficult and expensive.
In hind sight it is easy to see where the safety factor should have been increased, but that isn't fair. You don't know in advance which part will fail, so you try to design critical systems to similar safety factors.
Sometimes you get it wrong - but even that is a trade-off in engineering costs. Additional engineering reviews take time and money - and may eliminate the project, or reduce its capabilities.
I am aware of another large accelerator project - the Next Linear Collider. Unless you are in the field you probably haven't heard of it. That's because the design was too expensive and it will never be built.
The interconnects are rather complex superconducting devices, not simple electronic connections. It certainly would have been possible to design them with a higher safety factor, but that would have increased the cost. If that approach had been taken with all of the critical components for the machine, the overall cost would have been significantly higher. Unfortunately for a large cutting edge project on a tight budget, you need to take some technical risks. Over the next 10 years we will see if they put a reasonable safety factor on the overall design.
I think this illustrates one of NASA's biggest problems. Different people have different and incompatible ideas of what its mission should be. They work on projects that take more than a decade, so changing missions with changing administrations can result in nothing getting done. Should they do manned space? Environmental monitoring? Aerospace R+D? Deep space science? These all require very different infrastructure.
My personal vote is for manned space and deep space science because I don't think any other (US) organization is likely to do these, but there are many other reasonable options. As a country we need to decide, and stick with that decision.
Anti lock brakes must allow some sort of electronic control unit to disable the breaking action when the tires loose traction. Is there a plausible scenario where a failure of that unit could be coupled to a failure of an electronic engine control?
To me space is a goal, not a means. We shouldn't do space because we need what is out there - we don't. We can create a happy stable (read static) society here on earth. We should do space because we WANT what is out there, because it would be a tragedy if we were too lazy to ever leave out planet.
When the guys on the ships wave at the guys on the shore, you want to be the guys on the ships.
There are lots of "diceless" systems - basically rock-scissors-paper variants.
I have this wonderful image of a 6'2, 300lb tattooed muscular prisoner whining about whether his 58th level paladin's holy sword being destroyed by enchanted rust-monsters.
I actually think games like D&D are a very good thing for prisoners - it teaches a variety of new ways to interact with people and non-violent ways to let off aggression.
There are good and bad things of all types in movies, I don't see why the UIs should be any different. Most are pretty poor, but there may be clever ideas here and there that could find their way into a real UI.
Personally I like large monitors for some types of control. The SLAC accelerator control room contains a large number of large monitors (covering most of the available space now. That way the operators can glance around the room and quickly get status on a large number of systems. This seems to be more efficient than selecting through display windows or having automatic alarms raise windows (both of which we've tried as well). For special purpose systems large monitors are cheaper (only a few thousand $), than custom software (which could run millions of $).
What surprises me is that the treatment was continued after the system appeared to be misbehaving. I work with a large (the world's largest actually), linear accelerator. We do not do medical work, but do have various radiation safety systems. When a safety system behaves in an unexpected fashion, the operators do no just "try again". The affected part of the system is shut down and the problem is investigated by experts. I have observed this in person and it appears to me that the operations staff takes this situation seriously and I believe would never proceed with beam operations if the safety systems we not operating as expected.
I would think that medical equipment would operate under the same standards. Operators and doctors should be trained to stop work any time the system does not respond as expected. (This is very simple: if the machine is not behaving exactly as specified in the operating procedures, STOP and call an expert). The "expert" is then held responsible for the correct functioning of the machine. If it fails after he gives it the ok - the line of responsibility is very clear.
I understand that there are serious consequences to shutting down a treatment center, but we sometimes shut down a billion-dollar accelerator center when there are questions about safety equipment. We of course keep experts on call so that any issues can be resolved quickly.
Disclaimer - I work at SLAC and represent what I have observed to the best of my ability, but I am not an official spokesman for the lab and am not directly involved in safety oversight.