This idea of doing spacecraft on the cheap comes up every few years.
In general, it's poor economy.
You see you have the fixed cost of the rocket, launchpad, and launch team. Many tens of millions of dollars. Even if you drove the spacecraft cost down to zero, it won't affect the total very much.
Meanwhile all the cost is at risk if the spacecraft fails.
In general it's penny wise and pound foolish to economize on the spacecraft.
The saving grace is you don't need much surface area coverage, just the edges and anything that might get perpendicular to the ground, and no real VOLUME of metal. Hair-thin wires and tiny glass beads with ion-flashed metal work just fine. Weight is not a problem.
Er, this looks really keen, but you have to consider the downside. Yes, there is a downside.
When fabricating chips, yes, you do want nice clean lines. Whopeee for clean lines. All hail clean lines. By coincidence, surface tension works towards cleaning up lines. Somebody should have patented surface tension. Too late now.
But eventually the nice clean lines end up at a transistor or resistor. There the rules are very different. You don't want surface tension to do its thing on the end of the line, which would be to shorten it. Very conveniently these nice pictures don't show what happens at the end of each line. How convenient.
Radar absorbing paint isn't as exotic as it sounds. Basically it's paint that is "black" at radar frequencies. Nothing more than iron or ferrite filings in a Rustoleum base. Or better yet, go to an airshow for a free sample. The F-16's usually have some good RAP flaking off by the nosegear cover hinges.
The japanese have been painting RAP on their skyscrapers for decades now to lessen FM and TV ghosting.
You're looking to "Wired" as a source of reliable information? Hmmm
Electromagnetic leakage was well known by 1943. So well known that sinece the mid 1930's the Navy had required all receivers to be specially designed as to not leak out any spurious signals such as the local oscillator, BFO, or IF signals. Plentifully documented in the user and service manuals of said radios.
The scope "spiked" because the teletype needed a whopping 60 milliamps of signal current from a high-voltage current-limited source. The edges of a 60-milliamp signal swinging almost 300 volts will radiate quite a ways from the unshielded patch cables of that day.
But the solution is trivial and inexpensive. A 30 cent capacitor and a 20 cent resistor across the signal wires will roll off the spikes very nicely. The remaining 75 baud signal will not radiate above the noise level.
Long ago there was found considerable evidence for heavy elements. If you peer at any chunk of mica you can find long dark tracks, longer and darker than are caused by any known type of radioactive decay.
The trick is finding incontrovertible proof of these atoms *before* they decay. If they have short half lives (short as in under ten million years or so), it's going to be hard to find their needleness in the haystack.
Sorry that I did not make my point clearly enough.
I did read TFA, and saw the TV show, and IMHO they're unconvincing.
If they were real scientists, they'd not only test Titanic's rivets, but also other rivets of that vintage that have been underwater.
One might suspect on general principles that Titanic's rivets were not all that different from ones used at that time.
And even if they were 'weaker", that says almost nothing about how long the ship would stay afloat. Rivets are the least important part of a riveted joint. And even if a joint holds, that often just concentrates the strain somewhere else, so a whole panel might fail. There's no way to logically connect "stronger rivets" with "less leakage".
It's a big jump from superconductivity in 45 or 47 atoms and usable superconductivity.
For instance, a usable superconductor has to be able to tolerate a strong magnetic field, i.e. substantial current. Plenty of alloys are superconducting but cannot carry much current.
And very basic: temperature is a very hazy concept when applied to a small cluster of atoms. What's the acceptable range of energies?
Very significant.
You see there are these things called "The Boston Gear gatalog", "Grainger", and many others. where you can over the Internet order most any mechanical part, and for 1/100'th the time and cost of making it yourself. And the part, if necessary, can be of Nylon, Teflon, aluminum, brass, bronze, steel, or composite. The part can have a porous bronze or a ball-cage bearing. The part can be machined to a close tolerance, at least ten times better than you can make at home.
Making your own parts sounds fantastic, but its unlikely to ever be practical or economical.
I find it hard to believe these guys can violate the laws of Physics, and in a big way.
Power lines and power transformers are optimized for passing 50 to 60 Hz. Not 50 to 60 MegaHertz!
Your typical wire in the air is going to lose about 99.9% of a 50MHz signal every city block, plus it will pick up tons of noise. I'd be surprised if they can emulate a single 10mbps twisted pair.
Let's think, a technology that has taken 60 years to go from lab to today's level, it's going to be superseded in five years by technology that has not yet made a single transistor or gate. Hmmmm..... Meanwhile silicon is not going to be improved in any obvious way, such as with ballistic-transistors, gallium-arsenide, silicon-carbide, 3-d geometries, process shrinkage, etc, etc, etc, etc, etc, etc.... No soup for you.
HP spent about 200 million on trying to sell a PC with a touch-sensitive screen. Remember the PC and the butterfly? Lots of TV ads and dang little in terms of sales.
Problem was, people soon figured out their arm got tired, you could not see what you were mousing over, the screen got smudged with fingerprints, and it's hard to click on a little checkbox when your fingertip is ten times bigger.
Looksee here folks, this all was well worked out in 1945. You order some low-inductance capacitors from Sprague. You have that smart guy Alvarez design some thin wire loops at the ends of matched lengths of RG-8/U coax. You design up a trigger that discharges the capacitors through a hydrogen thyratron into the coax. Thing go boom.
If you want to get all 1960's, replace the thyratron with a krytron from a Xerox machine. Even better boom.
one does not need to see some current "nosecones" or "nuclear triggers" to get a heck of a bang. Although the NK's could probably use a little brushing up on the details.
These radiological monitors are not going to catch the really bad stuff-- highly enriched uranium or plutonium. Those can be shielded by a millimeter of lead. ABC news and others have taken pounds of HEU through the expensive cargo scanners at several ports with no bells going off.
Okay, let's do the math. The human body dissipates about 150 watts through a surface area of around two square yards. That's about 2600 square inches. Let's say you used a 5x5 inch patch. That's 25 square inches, about 1% of the body surface. So you could at best capture 1% of 150, or 1.5 watts of heat. The heat to electricity efficiency of a typical thermocouple is about 3%. So we might get 45 milliwatts of electricity. Maybe enough to power a watch or calculator or very slow (5 MHz) computer. By comparison a single lithium AA cell can put out 45 milliwatts for about 120 hours.
I wish reporters had to take a class in basic science.
You can't effectively harvest body heat. The efficiency of any heat engine is proportional to the temperature drop, in absolute degrees. The internal body temperature gradient is unlikely to be much more than a degree Farenheit. So any heat engine in the body is limited to an absolute best efficiency of under a quarter of a percent. And you'd have to find some working fluid that changes phase across that temperature range. Not very likely. You could do a thousand times better harnessing the heatbeat energy with a microphone. And even that's ridiculous.
it's unfortunate but it's trivially easy to do the math on this one:
Lasers are rather expensive (xx million) and inefficient, like 15%
White paint and/or titanium foil is very cheap (a million times cheaper) and very ( > 70%) efficient at reflecting incident energy.
Ablative material that can generate smoke when heated and block a laser beam is REALLY cheap. Like free, as in branches and sod.
It makes absolutely no economic sense to use a xx million dollar laser of 15% efficiency to try to burn through a tank that can be effectively protected for a millionth the cost of the laser.
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In general, it's poor economy.
You see you have the fixed cost of the rocket, launchpad, and launch team. Many tens of millions of dollars. Even if you drove the spacecraft cost down to zero, it won't affect the total very much.
Meanwhile all the cost is at risk if the spacecraft fails.
In general it's penny wise and pound foolish to economize on the spacecraft.
The saving grace is you don't need much surface area coverage, just the edges and anything that might get perpendicular to the ground, and no real VOLUME of metal. Hair-thin wires and tiny glass beads with ion-flashed metal work just fine. Weight is not a problem.
When fabricating chips, yes, you do want nice clean lines. Whopeee for clean lines. All hail clean lines. By coincidence, surface tension works towards cleaning up lines. Somebody should have patented surface tension. Too late now.
But eventually the nice clean lines end up at a transistor or resistor. There the rules are very different. You don't want surface tension to do its thing on the end of the line, which would be to shorten it. Very conveniently these nice pictures don't show what happens at the end of each line. How convenient.
The japanese have been painting RAP on their skyscrapers for decades now to lessen FM and TV ghosting.
The solution is the same for all the data paths.
Round off the spikes with a RC Low-Pass filter and/or shield the wires.
75-baud data does not radiate much with anything less than a quarter-wavelength of signal cable (about 22,00 miles)
Electromagnetic leakage was well known by 1943. So well known that sinece the mid 1930's the Navy had required all receivers to be specially designed as to not leak out any spurious signals such as the local oscillator, BFO, or IF signals. Plentifully documented in the user and service manuals of said radios.
The scope "spiked" because the teletype needed a whopping 60 milliamps of signal current from a high-voltage current-limited source. The edges of a 60-milliamp signal swinging almost 300 volts will radiate quite a ways from the unshielded patch cables of that day.
But the solution is trivial and inexpensive. A 30 cent capacitor and a 20 cent resistor across the signal wires will roll off the spikes very nicely. The remaining 75 baud signal will not radiate above the noise level.
Long ago there was found considerable evidence for heavy elements. If you peer at any chunk of mica you can find long dark tracks, longer and darker than are caused by any known type of radioactive decay. The trick is finding incontrovertible proof of these atoms *before* they decay. If they have short half lives (short as in under ten million years or so), it's going to be hard to find their needleness in the haystack.
I did read TFA, and saw the TV show, and IMHO they're unconvincing.
If they were real scientists, they'd not only test Titanic's rivets, but also other rivets of that vintage that have been underwater.
One might suspect on general principles that Titanic's rivets were not all that different from ones used at that time.
And even if they were 'weaker", that says almost nothing about how long the ship would stay afloat. Rivets are the least important part of a riveted joint. And even if a joint holds, that often just concentrates the strain somewhere else, so a whole panel might fail. There's no way to logically connect "stronger rivets" with "less leakage".
Very shaky resasoning in that article, IMHO.
What a load of total crap.
For instance, a usable superconductor has to be able to tolerate a strong magnetic field, i.e. substantial current. Plenty of alloys are superconducting but cannot carry much current.
And very basic: temperature is a very hazy concept when applied to a small cluster of atoms. What's the acceptable range of energies? Very significant.
Our Sun puts out about 4 x 10^24 watts, continuously, for billions of years.
So this laser is only putting out about one four-billionth of the Sun, and only for a very split second.
It's also very misleading if they intended to compare brightness per unit area. Even a cheap laser pointer is brighter than the surface of the Sun.
You see there are these things called "The Boston Gear gatalog", "Grainger", and many others. where you can over the Internet order most any mechanical part, and for 1/100'th the time and cost of making it yourself. And the part, if necessary, can be of Nylon, Teflon, aluminum, brass, bronze, steel, or composite. The part can have a porous bronze or a ball-cage bearing. The part can be machined to a close tolerance, at least ten times better than you can make at home.
Making your own parts sounds fantastic, but its unlikely to ever be practical or economical.
I find it hard to believe these guys can violate the laws of Physics, and in a big way. Power lines and power transformers are optimized for passing 50 to 60 Hz. Not 50 to 60 MegaHertz! Your typical wire in the air is going to lose about 99.9% of a 50MHz signal every city block, plus it will pick up tons of noise. I'd be surprised if they can emulate a single 10mbps twisted pair.
Let's think, a technology that has taken 60 years to go from lab to today's level, it's going to be superseded in five years by technology that has not yet made a single transistor or gate. Hmmmm..... Meanwhile silicon is not going to be improved in any obvious way, such as with ballistic-transistors, gallium-arsenide, silicon-carbide, 3-d geometries, process shrinkage, etc, etc, etc, etc, etc, etc.... No soup for you.
One can always play with the criteria to get any desired winner.
Going by raw number of anything you lose any distinctions as to the severity or impact of each problem.
In general a buffer-overflow in the Windows kernel is a heck of a lot more dangerous than a similar problem in OSX can ever be.
Problem was, people soon figured out their arm got tired, you could not see what you were mousing over, the screen got smudged with fingerprints, and it's hard to click on a little checkbox when your fingertip is ten times bigger.
If you want to get all 1960's, replace the thyratron with a krytron from a Xerox machine. Even better boom.
one does not need to see some current "nosecones" or "nuclear triggers" to get a heck of a bang. Although the NK's could probably use a little brushing up on the details.
Okay, let's do the math. The human body dissipates about 150 watts through a surface area of around two square yards. That's about 2600 square inches. Let's say you used a 5x5 inch patch. That's 25 square inches, about 1% of the body surface. So you could at best capture 1% of 150, or 1.5 watts of heat. The heat to electricity efficiency of a typical thermocouple is about 3%. So we might get 45 milliwatts of electricity. Maybe enough to power a watch or calculator or very slow (5 MHz) computer. By comparison a single lithium AA cell can put out 45 milliwatts for about 120 hours.
You can't effectively harvest body heat. The efficiency of any heat engine is proportional to the temperature drop, in absolute degrees. The internal body temperature gradient is unlikely to be much more than a degree Farenheit. So any heat engine in the body is limited to an absolute best efficiency of under a quarter of a percent. And you'd have to find some working fluid that changes phase across that temperature range. Not very likely. You could do a thousand times better harnessing the heatbeat energy with a microphone. And even that's ridiculous.
Please explain how the entanglement survives the photon's many interactions with the atmosphere and the mirror.
AFAIK entanglement won't survive any non-unitary interaction, like scattering or reflection.
it's unfortunate but it's trivially easy to do the math on this one:
It makes absolutely no economic sense to use a xx million dollar laser of 15% efficiency to try to burn through a tank that can be effectively protected for a millionth the cost of the laser.