When the air inside a ramjet exceeds the speed of sound (meaning an aircraft speed of around Mach 5+) combustion fails to occur properly. This is overcome in a scramjet (supersonic combustion ramjet). Scramjets are a new concept still in the research stages. Usually, the inlet is much wider (typically the entire underside of the craft) so the compression is less and the air remains at supersonic speeds. Some designs use reactive chemicals or gases other than standard jet fuel. Normally, the design of the jet is much more complex. Like a ramjet the scramjet must already be moving extremely fast before it will start working, but theoretically, speeds in excess of Mach 20 are possible.
I'm wondering if they can justify the cost to the bean counters higher up.
It's an actual science experiment that can be done on the ISS. Given the political realities, that alone is sufficient justification for the expense. Bean != bean.
using the grid as a backup for their own power generation rather than the other way round
This is exactly the market FuelCell Energy is selling their 250kW and (soon) 1MW units into - Hospitals, Hotels, Computer Centers, the places that need absolutely reliable power. The beauty of their molten carbonate fuel cells is that they can run directly on a wide range of hydrocarbon fuels: methanol, natural gas, marine diesel, coal mine methane, sewage digester gas, you name it. With combined cycle they reach 80% efficiency at near-zero emissions (apart from the inevitable CO2). Beautiful technology. Still expensive, but looking more attractive with every major blackout (next summer, anyone?).
Re:He's misinformed on a geopolitical resource sca
on
The Wrong Stuff
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· Score: 1
I think the realization of the importance of these things is the driving force behind the president's renewed interest in space and the moon.
While your argument has merit, I think you are overestimating the IQ of your current president by a factor of 2-3. He does not think nor plan beyond re-election.
Thanks for the concern, but I think my karma can take it.:-) Even the most fair and transparent voting process can't make the voters any smarter... anyway, it self-corrected now to
80% Interesting 10% Offtopic 10% Overrated
Meta-moderators: get those two bastards! Just kidding:-)
With Diebold's flaws being exposed, it may be a good time to effect some real change. What are the chances of this being actually adopted for some election?
string theory describes nor predicts nothing that is not explained by another larger theory
There is always an infinite number of hypotheses that are consistent with all available observations. To pick among those, science relies on two principles:
1) Falsifiability: for a hypothesis to be the subject of scientific discourse, there must be some experiment or observation that could disprove it. This eliminates hypotheses such as "God made it so" and "our universe is just the holodeck of the Enterprise" from the realm of science, since they can never be falsified: *any* new observation will fit into them. A hypothesis that survives tests that could have falsified it is called a theory.
Falsifiability is also used to prioritize science: a hypothesis which cannot be tested in the foreseeable future is not worth putting too much effort in at this point. A lot of high-energy physics works that way: the hypotheses that can be tested by the next generation of accelerators receive the most attention.
2) Occam's Razor: among competing theories or hyptheses, the simplest is preferred. Kepler's heliocentric model of the solar system didn't fit the observations any better than a sufficiently elaborate system of Ptolemaeic epicycles, but it was much simpler, therefore better.
Now the problem with string theories is that while individual string theories are falsifiable, the space of possible string theories is so vast that for any possible universe a string theory that fits it can be found. It would therefore be more accurate to speak of the "string hypothesis" at this point. Whether it survives will depend on will depend on Occam's Razor: will the simplest string theory that remains standing (i.e., consistent with all observations) be simpler than the simplest non-string theory, or not?
At the moment the string theories are ahead, but only because we do not have a reasonably simple non-string theory that fits our observations. Nobody (including string theorists) is terribly happy about it, but it's what we've got. Are we chasing Ptolemaeic epicycles? Time will tell.
I remember back when the Mac first got voice-activated menus (over 10 years ago), our secretary liked them... so whenever we were passing by her office, we'd stick our head in and say "select - all files - move - trash - yes" (or whatever the magic sequence was) by way of greeting.:-)
You're of course free to continue calling cetaceans fish and believing in brontosauri that never existed (they were a shoddy/fraudulent paleontologist's chimera), but just because you think you shouldn't ever have to learn anything new after grade school doesn't give you the right to criticize others for showing more intellectual flexibility.
I also think, for the record, that if something as large as Luna, or Titan, or Europa were out floating in space orbiting the sun and not another planet, they would be considered planets too.
Do you realize just *how many* Sedna-size (and larger) objects we are bound to find out in the Kuiper belt? Trans-Neptunian space is truly vast, and very ill-lit - we have not even begun to scratch the surface of what's lurking there. Calling the thousands or millions of sizeable Kuiper belt objects we will discover over time all "planets" serves *no* purpose but deprives us of a term to denote the 4 major rocky bodies orbiting the sun inside the asteroid belt, and the 4 gas giants orbiting the sun between the asteroid and Kuiper belts, without the ludicrous verbiage to which I'm going here.
As we discover more about the denizens of the Kuiper belt, we are likely to require more new terms to denote sub-populations - all the more reason to stay away from the already overburdened "planet" category. Pluto is a captured Kuiper belt object, and should be labeled as such. Finally, as someone else has pointed out, there are real differences between Kuiper belt objects (including Pluto) and true planets as to their orbital parameters.
> How many computer manufacturers are based in England, compared to the USA
I'd say the ratio is about 0:0
Exactly! Over 2/3 of all laptops are actually made by Taiwanese "original design manufacturers" (ODMs), whether they're sold as Dells, Compaqs, Toshibas, Sonys, Fujitsus, IBMs, or Apples. It used to be that Taiwan "contract manufactured" laptops designed in the US or Japan, but nowadays the Taiwanese provide almost everything from concept to design to worldwide direct shipping and customer support. Taiwan's gotten too expensive to do the actual manufacturing, so they're moving that to mainland China and Indonesia.
What you think of a "computer manufacturer" is more often than not just a corporate shell taking care of the brand and the stockholders, with everything else subcontracted out. Ever wonder why some of the newer Powerbooks and Toshibas look similar? Same Taiwanese ODM . Ever wonder why Compaq maintains 2 separate laptop lines, Armada and Presario? Different Taiwanese ODMs.
That's 4 years from first stepping out into space to landing and stepping out onto the moon. The current plan is not to step on the moon within 4 years
Hmmm... and you think that doing things over 20 years instead of 4 is going to make the project *cheaper*? Uh huh... can I interest you in some prime real estate on the moon?
you must remember that some of the R&D work is already done.
Not really. R&D work done 40 years ago is worthless today. You can't build things (Saturn V, LEM, what have you) the same way since the suppliers for even the most basic parts (back then) are long gone. Easier to redesign from scratch than to try to reenact history. But we all know how fast, cheap, and effective NASA has become in the spacecraft design department, right? Not.
In April and May of this year, two naked-eye comets, C/2001 Q4 and C/2002 T7, will grace the twilight skies. To spot the cosmic balls of dust and ice look to the west at dusk or dawn.
Look to the west at dusk *or* dawn? Yeah right. Probably got shortened by an overzealous editor from the correct "to the west at dusk or the east at dawn". Amazingly inept editing for an astrobiology site. The linked article has more (and correct) information.
COuld someone just accept Pluto and Sedna as planets regardless of size?
Why? Because it gives you a warm fuzzy feeling? Will you still feel the same when the 10'000th Kuiper Belt "planet" the size of Sedna will be discovered? And it will, eventually - there's a huge amount of ill-light space that far from the sun, and we've barely scratched the surface of all that's bound to be lurking out there. We should really reserve a term (or two) to denote a) the four sizeable rocky bodies orbiting the sun inside the asteroid belt, and b) the four gas giants orbiting the sun between the asteroid belt and the Kuiper belt.
Pluto is a special case: on one hand it looks like what we would expect from a typical Kuiper belt object (KBO), on the other it is bound to be the closest large KBO by far. Historically it was discovered (the same as Neptune) by its perturbative effect on another planet's orbit, long before any other KBOs, so it gets grandfathered in as an honorary "planet". Fair enough.
Sedna, on the other hand, is three times (!) as far out from the sun as Pluto; at that distance we expect to find thousands of KBOs of comparable size. Calling them all "planets" would be like starting to call all schools of whatever level "university" - a status grab that would ultimately achieve nothing but a devaluation of the more prestigious term, and a muddling of the underlying factual distinctions.
Well this was before 9/11, and I sincerely hope they weren't *flying the plane* off the same overburdened Pentium... I can just see it, next time they dig up the cockpit voice recorder from a crashed airliner:
Pilot: "The flight control app is not responding! Quick, try to kill it!" Copilot: "The mouse is frozen... must... use... three-fingered salute..." Pilot: "Still no response... okay, I'm gonna power-cycle the bastard." Plane: (plummets 20'000 ft while they wait out the boot sequence) Computer: All Your Boot Are Belong To Us. Pilots: "Somebody has sent us up the virus! Aiiieeeee!" Plane: *crash*
while Russia is now a democracy, they are still communist
That's a good one; they're actually neither. They're rapidly morphing into the same kind of post-capitalist information oligarchy that everybody else is heading towards, wherein a veneer of democracy and free markets thinly disguises the fact that whoever controls the mass media has all the power.
Consider: China is heading towards free markets and (local) elections but keeps a tight grip on its media. In Italy the media czar is also the president, and brazenly changes laws so as to evade corruption charges. Across the Anglo-Saxon world, virtually all the mass media are in the hands of only a half-dozen moguls, and religiously toe the government line.
This new game is played by smart people, they've all read the sign of the times. It's the post-capitalist feedback loop of money and power: the media shape public opinion, public opinion elects politicians, the politicians decide where the money goes, the money buys control of the media. Welcome to the information society.
Reminds me of a couple of years back when by wiggling their god-awful pointer device too fast I managed to crash the in-flight seat-back entertainment system. BSOD, reboot, turns out it's a 90MHz Pentium running Win NT 4.0 Server Edition - no wonder the response was so sluggish (on the order of seconds).
I got to the desktop for about 5 seconds before their entertainment app autostarted again. I then spent a fun hour or two re-crashing the blasted thing and trying to defeat the autostart. Never managed it though - that's the only time I recall that I wished I knew more about Windows.:-)
Eventually I had to stop because it turned out that poor old Pentium wasn't my in-seat client but actually the server for the entire cabin, and a lynch mob was starting to form... 8-O
This is one aspect of the current NIAC Phase II study. The third conference on space elevators is coming up and should provide a venue for such discussions. This is quickly morphing from a one-man show (Brad Edwards) into a respectable research area.
Wow, and I thought the space shuttles could only go to measly LEO! So, can we send Bush to Sedna on one of them? Soon? Please? There could be a problem in that Sedna's orbital inclination might not match that of the ISS, but for this worthy cause we should really make an exception. NASA, are you listening?
Eggsactly! Unique is the company managing Zurich airport, and since the term is trademarked, any magnetic field claiming to be "so unique" had better get a license!
PS: "sing of a flaccid mind" is an exhortation, making the subject line ungrammatical.
Oh, I completely agree that their estimates are quite optimistic. The point is, even if they should overrun them by a factor of 2, 5, or 10, it still would be an extremely attractive project that should be given serious consideration. People cling to notions from the days when a space elevator was the sole province of science fiction - we'd have to capture an asteroid, we'll never have a material strong enough, it would short out the atmosphere, if it fell it would crush everything near the equator, etc. Now is the time to leave fiction behind and face up to the fact that we can actually build and safely operate this thing within a reasonable time frame and budget.
If Bush was serious about giving "vision and focus" to space exploration, he should have set NASA the goal of building a space elevator by 2020. Exploration, commercial exploitation, and colonization of space (Mars, anyone?) would then become economically viable for the private sector, and thus all but inevitable.
Not needed. Read the NIAC Phase I report - a space elevator could be deployed with the equivalent of 7 shuttle launches. Total cost has been estimated as low as 15B US$ - compare that to the ISS and other boondoggle programs.
The only technology required that we don't yet have is mass-production of carbon nanotube cables, and that looks like it will happen within the next couple of years.
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From Wikipedia:
When the air inside a ramjet exceeds the speed of sound (meaning an aircraft speed of around Mach 5+) combustion fails to occur properly. This is overcome in a scramjet (supersonic combustion ramjet). Scramjets are a new concept still in the research stages. Usually, the inlet is much wider (typically the entire underside of the craft) so the compression is less and the air remains at supersonic speeds. Some designs use reactive chemicals or gases other than standard jet fuel. Normally, the design of the jet is much more complex. Like a ramjet the scramjet must already be moving extremely fast before it will start working, but theoretically, speeds in excess of Mach 20 are possible.
The amount of information a yes/no answer conveys to someone with no prior knowledge. Or, if you want to get technical: an ln(2) reduction in entropy.
What's up is that our telescopes are getting good enough to see those tiny rocks.
I'm wondering if they can justify the cost to the bean counters higher up.
It's an actual science experiment that can be done on the ISS. Given the political realities, that alone is sufficient justification for the expense. Bean != bean.
using the grid as a backup for their own power generation rather than the other way round
This is exactly the market FuelCell Energy is selling their 250kW and (soon) 1MW units into - Hospitals, Hotels, Computer Centers, the places that need absolutely reliable power. The beauty of their molten carbonate fuel cells is that they can run directly on a wide range of hydrocarbon fuels: methanol, natural gas, marine diesel, coal mine methane, sewage digester gas, you name it. With combined cycle they reach 80% efficiency at near-zero emissions (apart from the inevitable CO2). Beautiful technology. Still expensive, but looking more attractive with every major blackout (next summer, anyone?).
I think the realization of the importance of these things is the driving force behind the president's renewed interest in space and the moon.
While your argument has merit, I think you are overestimating the IQ of your current president by a factor of 2-3. He does not think nor plan beyond re-election.
Thanks for the concern, but I think my karma can take it. :-) Even the most fair and transparent voting process can't make the voters any smarter... anyway, it self-corrected now to
:-)
80% Interesting
10% Offtopic
10% Overrated
Meta-moderators: get those two bastards! Just kidding
With Diebold's flaws being exposed, it may be a good time to effect some real change. What are the chances of this being actually adopted for some election?
string theory describes nor predicts nothing that is not explained by another larger theory
There is always an infinite number of hypotheses that are consistent with all available observations. To pick among those, science relies on two principles:
1) Falsifiability: for a hypothesis to be the subject of scientific discourse, there must be some experiment or observation that could disprove it. This eliminates hypotheses such as "God made it so" and "our universe is just the holodeck of the Enterprise" from the realm of science, since they can never be falsified: *any* new observation will fit into them. A hypothesis that survives tests that could have falsified it is called a theory.
Falsifiability is also used to prioritize science: a hypothesis which cannot be tested in the foreseeable future is not worth putting too much effort in at this point. A lot of high-energy physics works that way: the hypotheses that can be tested by the next generation of accelerators receive the most attention.
2) Occam's Razor: among competing theories or hyptheses, the simplest is preferred. Kepler's heliocentric model of the solar system didn't fit the observations any better than a sufficiently elaborate system of Ptolemaeic epicycles, but it was much simpler, therefore better.
Now the problem with string theories is that while individual string theories are falsifiable, the space of possible string theories is so vast that for any possible universe a string theory that fits it can be found. It would therefore be more accurate to speak of the "string hypothesis" at this point. Whether it survives will depend on will depend on Occam's Razor: will the simplest string theory that remains standing (i.e., consistent with all observations) be simpler than the simplest non-string theory, or not?
At the moment the string theories are ahead, but only because we do not have a reasonably simple non-string theory that fits our observations. Nobody (including string theorists) is terribly happy about it, but it's what we've got. Are we chasing Ptolemaeic epicycles? Time will tell.
I remember back when the Mac first got voice-activated menus (over 10 years ago), our secretary liked them... so whenever we were passing by her office, we'd stick our head in and say "select - all files - move - trash - yes" (or whatever the magic sequence was) by way of greeting. :-)
If you can tear your eyes away from the JPL rovers for a second, Mars Express has answered that question last week.
You're of course free to continue calling cetaceans fish and believing in brontosauri that never existed (they were a shoddy/fraudulent paleontologist's chimera), but just because you think you shouldn't ever have to learn anything new after grade school doesn't give you the right to criticize others for showing more intellectual flexibility.
I also think, for the record, that if something as large as Luna, or Titan, or Europa were out floating in space orbiting the sun and not another planet, they would be considered planets too.
Do you realize just *how many* Sedna-size (and larger) objects we are bound to find out in the Kuiper belt? Trans-Neptunian space is truly vast, and very ill-lit - we have not even begun to scratch the surface of what's lurking there. Calling the thousands or millions of sizeable Kuiper belt objects we will discover over time all "planets" serves *no* purpose but deprives us of a term to denote the 4 major rocky bodies orbiting the sun inside the asteroid belt, and the 4 gas giants orbiting the sun between the asteroid and Kuiper belts, without the ludicrous verbiage to which I'm going here.
As we discover more about the denizens of the Kuiper belt, we are likely to require more new terms to denote sub-populations - all the more reason to stay away from the already overburdened "planet" category. Pluto is a captured Kuiper belt object, and should be labeled as such. Finally, as someone else has pointed out, there are real differences between Kuiper belt objects (including Pluto) and true planets as to their orbital parameters.
> How many computer manufacturers are based in England, compared to the USA
I'd say the ratio is about 0:0
Exactly! Over 2/3 of all laptops are actually made by Taiwanese "original design manufacturers" (ODMs), whether they're sold as Dells, Compaqs, Toshibas, Sonys, Fujitsus, IBMs, or Apples. It used to be that Taiwan "contract manufactured" laptops designed in the US or Japan, but nowadays the Taiwanese provide almost everything from concept to design to worldwide direct shipping and customer support. Taiwan's gotten too expensive to do the actual manufacturing, so they're moving that to mainland China and Indonesia.
What you think of a "computer manufacturer" is more often than not just a corporate shell taking care of the brand and the stockholders, with everything else subcontracted out. Ever wonder why some of the newer Powerbooks and Toshibas look similar? Same Taiwanese ODM . Ever wonder why Compaq maintains 2 separate laptop lines, Armada and Presario? Different Taiwanese ODMs.
That's 4 years from first stepping out into space to landing and stepping out onto the moon. The current plan is not to step on the moon within 4 years
Hmmm... and you think that doing things over 20 years instead of 4 is going to make the project *cheaper*? Uh huh... can I interest you in some prime real estate on the moon?
you must remember that some of the R&D work is already done.
Not really. R&D work done 40 years ago is worthless today. You can't build things (Saturn V, LEM, what have you) the same way since the suppliers for even the most basic parts (back then) are long gone. Easier to redesign from scratch than to try to reenact history. But we all know how fast, cheap, and effective NASA has become in the spacecraft design department, right? Not.
From the article:
In April and May of this year, two naked-eye comets, C/2001 Q4 and C/2002 T7, will grace the twilight skies. To spot the cosmic balls of dust and ice look to the west at dusk or dawn.
Look to the west at dusk *or* dawn? Yeah right. Probably got shortened by an overzealous editor from the correct "to the west at dusk or the east at dawn". Amazingly inept editing for an astrobiology site. The linked article has more (and correct) information.
COuld someone just accept Pluto and Sedna as planets regardless of size?
Why? Because it gives you a warm fuzzy feeling? Will you still feel the same when the 10'000th Kuiper Belt "planet" the size of Sedna will be discovered? And it will, eventually - there's a huge amount of ill-light space that far from the sun, and we've barely scratched the surface of all that's bound to be lurking out there. We should really reserve a term (or two) to denote a) the four sizeable rocky bodies orbiting the sun inside the asteroid belt, and b) the four gas giants orbiting the sun between the asteroid belt and the Kuiper belt.
Pluto is a special case: on one hand it looks like what we would expect from a typical Kuiper belt object (KBO), on the other it is bound to be the closest large KBO by far. Historically it was discovered (the same as Neptune) by its perturbative effect on another planet's orbit, long before any other KBOs, so it gets grandfathered in as an honorary "planet". Fair enough.
Sedna, on the other hand, is three times (!) as far out from the sun as Pluto; at that distance we expect to find thousands of KBOs of comparable size. Calling them all "planets" would be like starting to call all schools of whatever level "university" - a status grab that would ultimately achieve nothing but a devaluation of the more prestigious term, and a muddling of the underlying factual distinctions.
Well this was before 9/11, and I sincerely hope they weren't *flying the plane* off the same overburdened Pentium... I can just see it, next time they dig up the cockpit voice recorder from a crashed airliner:
Pilot: "The flight control app is not responding! Quick, try to kill it!"
Copilot: "The mouse is frozen... must... use... three-fingered salute..."
Pilot: "Still no response... okay, I'm gonna power-cycle the bastard."
Plane: (plummets 20'000 ft while they wait out the boot sequence)
Computer: All Your Boot Are Belong To Us.
Pilots: "Somebody has sent us up the virus! Aiiieeeee!"
Plane: *crash*
while Russia is now a democracy, they are still communist
That's a good one; they're actually neither. They're rapidly morphing into the same kind of post-capitalist information oligarchy that everybody else is heading towards, wherein a veneer of democracy and free markets thinly disguises the fact that whoever controls the mass media has all the power.
Consider: China is heading towards free markets and (local) elections but keeps a tight grip on its media. In Italy the media czar is also the president, and brazenly changes laws so as to evade corruption charges. Across the Anglo-Saxon world, virtually all the mass media are in the hands of only a half-dozen moguls, and religiously toe the government line.
This new game is played by smart people, they've all read the sign of the times. It's the post-capitalist feedback loop of money and power: the media shape public opinion, public opinion elects politicians, the politicians decide where the money goes, the money buys control of the media. Welcome to the information society.
Reminds me of a couple of years back when by wiggling their god-awful pointer device too fast I managed to crash the in-flight seat-back entertainment system. BSOD, reboot, turns out it's a 90MHz Pentium running Win NT 4.0 Server Edition - no wonder the response was so sluggish (on the order of seconds).
:-)
I got to the desktop for about 5 seconds before their entertainment app autostarted again. I then spent a fun hour or two re-crashing the blasted thing and trying to defeat the autostart. Never managed it though - that's the only time I recall that I wished I knew more about Windows.
Eventually I had to stop because it turned out that poor old Pentium wasn't my in-seat client but actually the server for the entire cabin, and a lynch mob was starting to form... 8-O
some credible third-party analysis
This is one aspect of the current NIAC Phase II study. The third conference on space elevators is coming up and should provide a venue for such discussions. This is quickly morphing from a one-man show (Brad Edwards) into a respectable research area.
40 years away from Earth in a space shuttle.
Wow, and I thought the space shuttles could only go to measly LEO! So, can we send Bush to Sedna on one of them? Soon? Please? There could be a problem in that Sedna's orbital inclination might not match that of the ISS, but for this worthy cause we should really make an exception. NASA, are you listening?
"unique" refers to one thing
Eggsactly! Unique is the company managing Zurich airport, and since the term is trademarked, any magnetic field claiming to be "so unique" had better get a license!
PS: "sing of a flaccid mind" is an exhortation, making the subject line ungrammatical.
Oh, I completely agree that their estimates are quite optimistic. The point is, even if they should overrun them by a factor of 2, 5, or 10, it still would be an extremely attractive project that should be given serious consideration. People cling to notions from the days when a space elevator was the sole province of science fiction - we'd have to capture an asteroid, we'll never have a material strong enough, it would short out the atmosphere, if it fell it would crush everything near the equator, etc. Now is the time to leave fiction behind and face up to the fact that we can actually build and safely operate this thing within a reasonable time frame and budget.
If Bush was serious about giving "vision and focus" to space exploration, he should have set NASA the goal of building a space elevator by 2020. Exploration, commercial exploitation, and colonization of space (Mars, anyone?) would then become economically viable for the private sector, and thus all but inevitable.
The first step is to capture an asteroid
Not needed. Read the NIAC Phase I report - a space elevator could be deployed with the equivalent of 7 shuttle launches. Total cost has been estimated as low as 15B US$ - compare that to the ISS and other boondoggle programs.
The only technology required that we don't yet have is mass-production of carbon nanotube cables, and that looks like it will happen within the next couple of years.