That is true of most forms of law enforcement. In fact, a law that is used against a small fraction of potential violators can reduce crime by those not targeted, particularly if the penalty (if caught) greatly exceeds the benefit of the crime.
However the ISS should *not* be canned. It works and the infrastructure has already been built. Why not use it instead of wasting the spent money completely?
Because it it of almost no value. The paltry results we could get from it do not justify the cost of continuing to operate it.
Now throw in interest costs (you are paying for development before you get any launches, and the value of the launches in the out years is heavily discounted), as well as a risk premium (there's a chance your $32 billion will be pissed away without getting a vehicle; NASA's recent track record in vehicle development is not encouraging.) The 128 launches balloon rather quickly.
As a rule of thumb, it doesn't make sense to design a new reusable or semireusable launch vehicle unless you're going to be using it at least 1000 times. Otherwise, the design costs don't get recouped. Realistically this means NASA is going to have to find enough payloads to launch one of these every week or so.
At current launch rates, NASA should stick with expendable vehicles.
For its time, and even for now, the Space Shuttle is a fairly good design.
Since the shuttle completely failed to achieve its primary goal (reducing the cost of putting payload into orbit), how can it be judged as anything other than a failure?
If congress had known in the 1970s how STS would turn out, they would have canned this turkey immediately.
No, the fundamental problem with STS was that demand for launch was never large enough to justify the development of expendable launchers.
If you look at other areas of technology, things get developed when there is enough demand to support multiple efforts. This was not the case with STS: NASA had to grab just about every launch opportunity there would be, and invent hundreds of fantasy launches, just to get enough traffic in their models to have the economic case close (on paper). Even that would not have been possible if STS was going to be only the first in a line of evolving vehicles.
The right thing to have done would have been to go back to the KISS principle and design simplified expendable launchers, like Schmitt's cost optimized concepts. These would have made sense even at low flight rates, and because you're always replacing them your opportunities for evolution are built right in.
Re:you never know where breakthroughs will happen
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Shuttle Politics
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History has shown you really never know where the next breakthrough or pre-breakthrough will come from. It is consquently nearly imposible to do a long term cost benefit analysis of one experimental program over another.
In that case, the obvious strategy is to have as many programs as possible (since, by your assumption, all are equivalent). This means you want a lot of small programs, not a few big programs. In other words, this is a very strong argument against very expensive manned space efforts.
No, because real human exploration isn't dependent on government programs. Humans didn't spread out of Africa under command of some god-emperor, they spread out due to multitude of local individual decisions.
The fact that manned spaceflight is concentrated in a bureaucracy shows it isn't really exploration, just a pale imitation.
Re:Why are we always nitpicking?
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Shuttle Politics
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They could have done that if they had planned to build more than one from the beginning. Restarting production would have been more expensive.
Yes..... it's just likely that it will be briefly UN-inhabitable if a moderate-sized rock hits.
No, even then most of the Earth's surface will still be more habitable. There will be water, and oxygen, and pressure. You can have massive stockpiles of food and equipment, and have them much more cheaply than on some other planet or in space.
Re:Why are we always nitpicking?
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Shuttle Politics
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· Score: 1
Then they would have launched the backup (they did have another mirror, made by another company, that was just fine.) Having done that, the first one would still have been usable for things like UV photometry.
As designed, it needed manned servicing, but there's nothing essential about that. HST's replacement, the NGST, will be launched on a Delta into an orbit that the shuttle cannot reach.
The shuttle is not used to refuel surveillance satellites, and in fact has never been used for that purpose. It now no longer even launches any surveillance satellites.
And yet, why was it that the Concorde was the plane that crashed, not any of the thousands of other aircraft that used that runway? Could it be that the higher takeoff speed, fuel tank design, and engine placement left the Concorde vulnerable to this kind of accident?
Commercial R&D had the advantage of focusing on the problems that make sense solving. Government R&D programs, or at least big ones, devolve into entitlement programs that persist long beyond the time they should have been terminated.
But there are antiviral drugs that are effective against the flu. Tamiflu, for example, is one of a class of recently introduced drugs called neuraminidase inhibitors that binds to and inactivates a protein on the virus necessary for its spread within the body.
Actually, if the star is made to bob up and down in the ring plane with sufficient amplitude (or, the ring bob up and down, if it's the lower mass of the two bodies) then the system can be dynamically stable.
Space fans are deluding themselves about the prospects of NASA doing anything useful in space. Eventually you'll realize what a gullible fool you've been and join us former fans on the dark side.
There's also the possibility that fresh LiOH cannisters could have been launched to the shuttle on an unmanned rocket (the shuttle would have rendevoused with the cargo carrier and been unloaded by astronauts in the space suits they had). The limit would then be electrical power. Oberg has suggested they would then turn off the systems in the back of the shuttle; the cold would ruin them, but they're lost at that point anyway.
You can (or could) buy hybrid rocket engines using rubber or plastic as the fuel and nitrous oxide as the oxidizer. These aren't explosive by themselves, so they should evade these limits.
Plutonium is enriched uranium. This is the whole point.
No, plutonium is not enriched uranium. Enriched uranium is uranium in which the isotope ratio has been changed, increasing the percentage of the atoms that are 235U.
You've also confused reactors that produce plutonium (basically, any reactor that has any 238U in its core) with breeder reactors (reactors that produce a net gain in fissionable material). Ordinary thermal reactors, including heavy water reactors, make plutonium, but they do not make enough of it to close the cycle and replace the 235U (or the Pu) they are consuming.
Like I said before: stop posting messages on a subject on which you are obviously and grossly ignorant.
Eventually the fuel rods shrink too far and lack the surface area needed to produce enough neutrons to continue the reaction. Since it's far too dangerous to try to combine spent rods (you'd have to heat-form them together outside of the mediating water, which risks an uncontrolled chain reaction), they're put into radiation-proof containers and sealed away in nuclear waste sites.
All completely bullshit. I have to conclude you're a troll.
The idea that the Japanese exploded a test atomic bomb is completely, utterly ludicrous. Their program was pathetic; they had very little resources devoted to it, and made little progress. Compare this to the US Manhattan project, which reached a size comparable to the US pre-war auto industry. Japan simply didn't have the industrial might to succeed.
Please, don't try to explain something you don't understand. Your explanation was completely bogus.
In reality, heavy water is used as a moderator (not 'mediator') in reactors. The reason is that deuterium has a much lower neutron absorption cross section than ordinary hydrogen, so more of the neutrons produced in fission survive to cause additional fission. Because of this increased 'neutron economy', a heavy water moderated reactor can use unenriched uranium. Ordinary water reactors need enriched uranium.
You statement about boiling off is crap -- if the moderator boils off, the reaction slows down.
And, you've confused decay and fission -- two separate nuclear processes.
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That is true of most forms of law enforcement. In fact, a law that is used against a small fraction of potential violators can reduce crime by those not targeted, particularly if the penalty (if caught) greatly exceeds the benefit of the crime.
Now throw in interest costs (you are paying for development before you get any launches, and the value of the launches in the out years is heavily discounted), as well as a risk premium (there's a chance your $32 billion will be pissed away without getting a vehicle; NASA's recent track record in vehicle development is not encouraging.) The 128 launches balloon rather quickly.
As a rule of thumb, it doesn't make sense to design a new reusable or semireusable launch vehicle unless you're going to be using it at least 1000 times. Otherwise, the design costs don't get recouped. Realistically this means NASA is going to have to find enough payloads to launch one of these every week or so.
At current launch rates, NASA should stick with expendable vehicles.
Erk, I meant 'justify the development of reusable launchers'.
If congress had known in the 1970s how STS would turn out, they would have canned this turkey immediately.
No, the fundamental problem with STS was that demand for launch was never large enough to justify the development of expendable launchers.
If you look at other areas of technology, things get developed when there is enough demand to support multiple efforts. This was not the case with STS: NASA had to grab just about every launch opportunity there would be, and invent hundreds of fantasy launches, just to get enough traffic in their models to have the economic case close (on paper). Even that would not have been possible if STS was going to be only the first in a line of evolving vehicles.
The right thing to have done would have been to go back to the KISS principle and design simplified expendable launchers, like Schmitt's cost optimized concepts. These would have made sense even at low flight rates, and because you're always replacing them your opportunities for evolution are built right in.
No, because real human exploration isn't dependent on government programs. Humans didn't spread out of Africa under command of some god-emperor, they spread out due to multitude of local individual decisions.
The fact that manned spaceflight is concentrated in a bureaucracy shows it isn't really exploration, just a pale imitation.
They could have done that if they had planned to build more than one from the beginning. Restarting production would have been more expensive.
Then they would have launched the backup (they did have another mirror, made by another company, that was just fine.) Having done that, the first one would still have been usable for things like UV photometry.
As designed, it needed manned servicing, but there's nothing essential about that. HST's replacement, the NGST, will be launched on a Delta into an orbit that the shuttle cannot reach.
The shuttle is not used to refuel surveillance satellites, and in fact has never been used for that purpose. It now no longer even launches any surveillance satellites.
And yet, why was it that the Concorde was the plane that crashed, not any of the thousands of other aircraft that used that runway? Could it be that the higher takeoff speed, fuel tank design, and engine placement left the Concorde vulnerable to this kind of accident?
Commercial R&D had the advantage of focusing on the problems that make sense solving. Government R&D programs, or at least big ones, devolve into entitlement programs that persist long beyond the time they should have been terminated.
But there are antiviral drugs that are effective against the flu. Tamiflu, for example, is one of a class of recently introduced drugs called neuraminidase inhibitors that binds to and inactivates a protein on the virus necessary for its spread within the body.
Actually, if the star is made to bob up and down in the ring plane with sufficient amplitude (or, the ring bob up and down, if it's the lower mass of the two bodies) then the system can be dynamically stable.
No, he *does* know what goes on up there.
Space fans are deluding themselves about the prospects of NASA doing anything useful in space. Eventually you'll realize what a gullible fool you've been and join us former fans on the dark side.
There's also the possibility that fresh LiOH cannisters could have been launched to the shuttle on an unmanned rocket (the shuttle would have rendevoused with the cargo carrier and been unloaded by astronauts in the space suits they had). The limit would then be electrical power. Oberg has suggested they would then turn off the systems in the back of the shuttle; the cold would ruin them, but they're lost at that point anyway.
If Ford had engineers that designed products with millions of parts, they'd fire them and hire more competent engineers.
The Space Shuttle's complexity is a bug, not a feature.
You can (or could) buy hybrid rocket engines using rubber or plastic as the fuel and nitrous oxide as the oxidizer. These aren't explosive by themselves, so they should evade these limits.
You've also confused reactors that produce plutonium (basically, any reactor that has any 238U in its core) with breeder reactors (reactors that produce a net gain in fissionable material). Ordinary thermal reactors, including heavy water reactors, make plutonium, but they do not make enough of it to close the cycle and replace the 235U (or the Pu) they are consuming.
Like I said before: stop posting messages on a subject on which you are obviously and grossly ignorant.
All completely bullshit. I have to conclude you're a troll.
The idea that the Japanese exploded a test atomic bomb is completely, utterly ludicrous. Their program was pathetic; they had very little resources devoted to it, and made little progress. Compare this to the US Manhattan project, which reached a size comparable to the US pre-war auto industry. Japan simply didn't have the industrial might to succeed.
Please, don't try to explain something you don't understand. Your explanation was completely bogus.
In reality, heavy water is used as a moderator (not 'mediator') in reactors. The reason is that deuterium has a much lower neutron
absorption cross section than ordinary hydrogen, so more of the neutrons produced in fission survive to cause additional fission. Because of this increased 'neutron economy', a heavy water moderated reactor can use unenriched uranium. Ordinary water reactors need enriched uranium.
You statement about boiling off is crap -- if the moderator boils off, the reaction slows down.
And, you've confused decay and fission -- two separate nuclear processes.