Well even if our galaxy do collide with the andromeda, chances are that only the structure of the galaxy is going to change, remember the huge distance between the stars. Two galaxies might pass right through each other without any collisions at all. Of cause the gravitational pull would create havoc in the orbital pathways of the individual stars around the galactic center, and perhaps send stars right out of the galaxy (as possibly shown on the 'horseshoe galaxy', cant remember where i saw it, but it looks like a horseshoe with a slight 'bump' at the bottom, which is interpreted as the two galactic nucli)
So most likely, the sun would not be affected unless the center of the andromeda passes near by (in astronomical terms!), if that happened (due to the much higher stelar density near a galaxy's core), then the planatary system might be destroyed as tidal forces would strip the planets away from the sun (could anyone say bad luck!). The sun would be unaffected however.
In order for individual stars to be affected, one would have to have a direct hit, just as implausible as Rutherfords famous backwards deflection in his experiment with shooting alphaparticles at a gold foil. 99.99% of the particles passed the foil with little or no deflection (He actualy used this information to calculate the diameter of the atomic nuclius relative to the atomic diameter).
You'r right, most of the earth's mantle is made of olivine (+ some pyroxene and oxide minerals) so in terms of volume olivine is the most common silicate mineral.
The most common mineral in the earth is iron-nickel alloy however, as the earth's core is made of this (although the outer core is molten, so that is not strictly a mineral (defined as having fixed structure and liquids don't)). The same stuff is found in iron meteorites, so quite much is known about this stuff.
Well enough about the earth's structure.
The interesting part about these new hydrothermal wents is the low temperature, and most importently, the heat source. All other hydrothermal wents known derive their energy from cooling magma (or recently solidified and hence still hot rock). These on the other hand, derive energy from reverse metamorphosis (normal metamorphic reactions goes like: low temperature rock ricn in water + heat + pressure => high presure,high temperature rock + free water . In this case the reaction runs the other way and water is bound to the rock and heat is liberated. This is only possible due to the fractures pressent in the sea floor allowing the water to come into contact with the olivine-containing rock. (i'm guessing, but it is most likely Dunite, a rock containing more than 90% olivine). The reaction 2 Mg2Si2O4 + 3 H2O => Mg3Si2O5(OH)4 + Mg(OH)2 liberates some heat and this heat (together with the water, leaches mineral out of the rock, these is then precipitated as the water cools as it exsits the seafloor. The minerals most easialy transported by low temperature fluids is carbonate minerals and quartz, but as quartz is not found together with olivine (reacts to form pyroxene) only the calcite is found. Thus the carbonate towers.
As shown by Microsoft (an honorable and trustworthy corporation) money cannot be made unless a company owns the patent. To let just
anyone reap the benefits of this knowledge would simply result in low cost (low cost=low value) products.
Then how do you explain Linux?? one of the most secure and stable operating systems avaliable..
Off topic i agree, but the fastest way to gain information and improove technology is by peer reveiw as in open source literature and science. Here anyone can test if the method is valid or the most efficient.
The experts have claimed that water has been responsible for a number of landforms on Mars (starting of course with the "rivers"). Oftentimes a new
theory will present itself, landforms resembling those on Earth, etc. and a plausible theory based on (say) CO2 flows could account for it. So we
shouldn't get all excited over this.
Except that in order for CO2 to become a liquid at all, you need an atmospheric pressure ABOVE that found here on earth (CO2 is 'dry ice' as it cannot exist in the liqid state unelss under pressure). If the beforementioned structures were to be verified as created by CO2-liquid, this would be a verry important and optimistic result, as the pressure on Mars vould have th have been much higher than today.
The structures found by the sattelites the past few years suggests that flowing water have existed on the surface of Mars in the past.
I hope it is still there (as some of the images returned have suggested, at least it was there some 10000 years ago), as this would make manned trips to Mars possible and practical.
Many landforms found on Mars have been made by flowing liquid (as they are so like those found on earth), and water is just the only plausible liquid avaliable on Mars.
As i recall, someone once proved, that random Brownian motion cannot be used to power anything (as it would create a perpetum mobile (spelling?))
They even proved, that you cannot rectify random events like that (i think they calculated using random photons or something..) as this would create the beforementioned perpetum mobile.
Thus as far as saying, that this motor-protein uses brownian motion is wrong. In order to generate motion you have to utilize a energy-releasing reaction (e.g converting ATP to ADP). Some others got it ringt as they described how a surplus of protons is used as driving force.
That thermal motion is improtant, is no surprise though, all reactions (almost) require an activation energy to occour (even decomposition of nitroglycerin, although it is small indeed).
The discovery of this motor protein and how it works by converting a chemical gradient to mechanical work, is interesting however.
You are probably right, as far as i remember, US cunsumption of electricity is more than double so high pr capita as it is in Europe (vestern that is). The reason for this is most likely, that the price on electricity have always been higher in Europe than in the US (eccept in some parts of Norway and Sveeden where they have cheap, old hydroelectric powerplants that gererate power at a price of 5 cent/KWH!.. I would love to live there..).
If the US started to build apliances that saves energy (not to mention building cars that don't burn a gallon evry 10 miles) a lot of energy and CO2 could be saved).
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Well Venice is an other matter (eg human interfere
on
City Beneath The Sea
·
· Score: 1
The reson for the subsidencen in the Venice laguna is that the cities in the area has been pumping fresh drinking water out of the sediments below the laguna. This has been done to such large an extent, that the sediments have started to compact. Furthermore, as in my response to the previous post, subsidence in river-deltas is a natural fenomena and observed at all big deltas.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Re:Alternate theory to why the city disappeared
on
City Beneath The Sea
·
· Score: 2
Sorry, but you misunderstand the theory of continental drift.
It is right that the continents drift with an average speed of 4 cm/year, but it is only at the boundry-zones (like San-Andreas in California) that the shift is observed. Within the plates, there is no lateral shift of one city relative to one other. Neither is the coastline a plate boundry. The plate boundry between Africa and Europe is much further north (between Cypres and Tyrkey), therefore shift along this boundry cannot be responsible for this.
Vertical shifts on the other hand, vould be exspected and observed in any large river delta, due to the constant addition of fresh sediments. These loads the underlying crust, and is responsible for slow subsidence (as observed at the Mississippi delta).
The reson for subsidence due to addition of material is that the earth's crust is isostatically compensated, that is it 'floats' on the denser mantle.
Such downwarping of the continental edges at large river-deltas most likely has drowned a lot of prehistoric cities.
A few years back i build a small device for my parallelport, it could support 8 different apliances at home (on/off only, booring now adays, i know). so i could have my 4x86 to brew cofee as well as start the toaster in the morning.
I only got to the testing phase, as i lost interest (plus the small problem with toasters and such turning on when i was not at home..)
It only cost me a burned out parallelport, as i forgot some resistors in the first model.. a.k.a. Ooops!
Well at least learnt to include protective resistors between computers and home made stuff..
(what's the safe stopping distance for an aircraft carrier;)).
Well you wouldent necesarrily have to stop, just either detonate at safe distance or turn (which in case of a carrier might be problematic though)
The way to store the plutonium correctly in a subduction zone would be to dril a hole through the sediments and into the basaltic ocean crust below (say 1 km of sediment and 1 km of basalt) and then seal the hole.
You don't even have to do it at the subduction trenches, one could just as safely and effectively do it almost anywhere on the ocean floor (eccept the ocean ridges for obvious reasons), and the result would be the same.
The basalt in the ocean crust is a stable and dense rock, and if one vould like to be completely safe, use a small nuclear warhead among the waste, and detonate once the hole is sealed. This would create a ball of basaltic glass encapsulating the waste.
This would prevent release effectively even over geological timescales (and also prevent 'smart' people to try to dig the plutonium up again).
And then again, perhaps not.
I once read (some 10 years ago) about how astronomers suddently discovered an astroid about 100 m in diameter as it was going away from the earth. Turned out it had passed within half the distance between earth and the moon, and they only found it after the close aproach.
If something that size hits a populated area (or ocean) then the toll in lives would be huge, as somethig that big would not airburst, but would penetrate the ground and create a crater at least 10 km wide. (not counting the firestorm and shockwave that propagate further out).
They didn't detect it before close aproach, as it was a rather dark object. One wonders how many other such objects is out there..
This is the one and most important reason for continuing space exploration! Earth isn't going to stick arround forever. So in order for the human race (or the race that exists at that time, (remember that the usual lifetime for a single species is roughly 2-4 milion years before it evolves into something different)) to survive ve have to spend time and effort into space exploration and space travel.
I have no idea whether the nitrogen semiconductor group used this apparatus or something else. I suppose that if you were clever enough to
find a fast way to take the measurements, you could just set off a bomb on top of the sample and measure for a few microseconds. Pressure is
difficult to control, but if you can measure pressure accurately while you do this, you can simply plot your data with pressure as one of the axes
This is exactly what is beeing done in nuclear testings and similar (non nuclear) experiments.
Real artificial diamonds for cutting tools can be made this way (and are as far as i know as it is an inexpensive method)
Yes. Ground movement before eruptions is comonplace and well documented. Several active volcanoes worldwide have tiltmeters and laser-rangefinders mounted all over the volcano, and small uplifts / enlargements of the volcano is observed before most eruptions. (for reference see Hawaii Volcano observatory update)
similarly, in Italy near Vesuvius (which blew up in AD. 79) ground movement in the sorounding area has been observed. Particularly near the town of Pozzuli which is situated above a magma-chamber. In the last 20 years the ground has been moving mostly upwards more than a meter! so that previously sunken Roman temples once again is above the water.
You'd probably be better off selling that electricity abroad.
Well you could do that, there is only one small problem with that. Energy transportation is far from loss free. I dont have the figures, but i would estimate that more than 5% of the energy (electric) produced in europe is lost in the transmission lines.
In order for levelling like you suggest, by transporting the energy to where there is need for it,would increase the transport loss dramaticly.
Conversely, by pumping water, you only lose a small amount of the energy, as hydroelectric turbines and electric water pumps are wery energy efficient. (approx 1% loss as far as I recall) => aprox 2% loss in the combined cycle.
The cables would have to be awfully thick (hence heavy) to transmit a decent amount of power 3 miles. Then you're wasting power just keeping
them up in the sky.
Well only if you use low voltage. Remember that P = U * I, and that resistance losses scale like I^2 * R. Thus if you transform the power to high voltage, then you can drastically reduce the powerloss in the transmission lines. (This is the reason for the use of high voltage transmission lines on the ground). Modern high voltage cables (100kV+) dont have to be air-born (as in wires suspended between towers) but can be dug into the ground. theseare somewhat heawy, bur that is only due to the external insulation.
In the case of the cables discussed here, the external insulation is not nescesserry, as the power in the cable could be cut off in case of a kite dropping out of the sky.
Well this all depends on the definition of a 'liquid'.
If the only definition of a liquid is that:
1) it lacks any long range order
2) it is isotropic (no changes in physcal properties with direction
3) it deforms plastically (i.e. flows; note no time scale given!)
then glass is a liquid. all glasses will deform given enough time. I'm not talking in minits here! Obsidian (wolcanic glass) do deform slowly over milions of years, Even at room temperature! Of couse it deforms much faster at elevated temperatures.
On the other hand, if a material deforms over time (like a candle or a glacier) does not mean that they too are liquids.
The problem here, is how we define a liquid. From the purely physical point of view, only the definition given in the beginning as well as a fourth one (thermodynamical one) is adequate:
4) liquids aquire internal thermodynamical equlibrium after a small temperature change (irrespectively to wether or not the liquid state is the stable state, alas applies also for supercooled liquids)
All supercooled liquids posess a transition temperature (as noted in the article above) called 'the glass transition temperatre', below which the physical poperties change from a classical liquid to that of an other state where local internal equlibrium is not maintained (the glass state). In this sense glasses is not liquids, but belong to their own group of materials: the Glasses
The glass transition temperature is not constant, but changes with cooling rate, as slower cooling allows the liquid to maintain internal equlibrium to lower temperatures. There is a lower limit, however, as a liquid below the melting temperature cannot have lower internal energy (Gibbs' free energy) than the crystaline phase. (for more comprehensive study: refer to Solid state Chemistry and its Applications by Anthony R. West)
Well enough physics for today: the bottom line is, if a glass is above the glass transition temperature, then is IS a liquid, if it is below it is NOT.
I can't think of a possible physical mechanism that directly links sunspots and influenza. But how about an intermediate step? Sunspots influence
weather. And weather... influences the transmission of influenza. Influenza is a seasonal disease, after all.
Actually the intermediate link you propose about the weather is correct. Recent discoveries by Eigil Friss-Christensen at Danish Space Research Institute indicates that there IS a correlation between solar activity (and sunspots) and mean temperature here on earth.
The correlation is that high solar activity and hence high solar wind density excludes some of the cosmic rays from the inner solar system. The lack of comsmic rays then cause fewer clouds to condensate and fewer clouds results in higher temperatures.
(check here for a link to the publications on this subject; search for 'Friis-Christensen' to find the relevant ones).
The slashdot title is a bit enthousiastic. Lake Vostok is about 1 million years old, but life on earth appeared some 3.5 billion years ago. It's not
like we're talking about frozen primordial life, we're talking about life evolved at 99.93%. Still, it could be interest
Nice to finally see someone who has some sense of perspective. The lake is only insulated for the last one milion years, and perhaps not even that.
Glacial ice moves, so does the antarctic ice sheet. Even though the lake has been covered by ice for over one milion yours, the just ice above the lake is most likely much yonger, and has thus contaminated the lake and 'reset' the lake at a later date.
The exact age of the ice obove the lake should be determinde as the drilling core reaches these parts of the ice, as one can count the years backwards from the surface (like counting year-rings in old trees)
The real interesting part from a geological and biological point of view (yep i'm a geologist) is if life exsists in the lake. Life can exsist at the bottom of the oceans (at the black smoker vents on East Pacific Rise at least) but if it can exsist in a almost frosen lake that has been isolated for 100.000+ years would be interresting to see.
There's also the problem of
superconductors breaking down in strong magnetic fields, which renders them useless for high-field applications. High-temperature
superconductors are especially bad for this.
I disagree. Most modern HTC's have a property called 'flux pinning'
Under high magnetic fields, the superconductor allows the magnetic field to recide in small 'tubes' within the superconductor. these tubes run through impurities in the ceramic, (which is non superconducting in any event) and is surrounded by supercurrents that keep the field lines in place.
as long as the circular currents is not so hing as to dissallow superconductivity, the bulk of the superconductor behaves as any normal one, that is it is superconducting.
This fenomenon is only found in the 'Type II' superconductors, but all the HighT ones belongs to this category (as far as i recall).
I believe the chambers are what are called pegmatites. I read of them years ago in a geology book and was utterly fascinated by the descriptions of gigantic crystals to be found in such chambers.
I disagree. Pegmatites are usually refered to as the last crystallized part of an igneous body (molten rock for the non geologists). Although many pegmatites do have huge crystals, they usually do not have such large open spaces as evident on the pictures. Furthermore, the location of the crystals in a silver and Zinc mine, suggests that the crystals have formed within a cavity created by flowing water (like Mammoth Caves in Kentucky) Furthermore, the mineralogy of the crystal cave in is not what you would expect from a regular pegamtite.
Normally pegmatites are formed form melts of the same composition as granite, so the prevalent minerals in pegmatites are usually Quarts, Feldspar and Biotite/Muscovite as well as more rare minerals as apatite and beryl. The crystals in the article is gypsum (CaSO4+2*H2O), which is not stable above 300C, which is incompatible with a molten origin
This IMHO proves that the crystal cave is not a pegmatite.
Having said that, i must admit i would like to se them up'n personal.. (too bad i live in Europe)
Slashdot Mirror
So most likely, the sun would not be affected unless the center of the andromeda passes near by (in astronomical terms!), if that happened (due to the much higher stelar density near a galaxy's core), then the planatary system might be destroyed as tidal forces would strip the planets away from the sun (could anyone say bad luck!). The sun would be unaffected however.
In order for individual stars to be affected, one would have to have a direct hit, just as implausible as Rutherfords famous backwards deflection in his experiment with shooting alphaparticles at a gold foil. 99.99% of the particles passed the foil with little or no deflection (He actualy used this information to calculate the diameter of the atomic nuclius relative to the atomic diameter).
Well guess that was my 2 cents
Yours Yazeran
Plan: To go to Mars one day with a hammer.
The most common mineral in the earth is iron-nickel alloy however, as the earth's core is made of this (although the outer core is molten, so that is not strictly a mineral (defined as having fixed structure and liquids don't)). The same stuff is found in iron meteorites, so quite much is known about this stuff.
Well enough about the earth's structure.
The interesting part about these new hydrothermal wents is the low temperature, and most importently, the heat source. All other hydrothermal wents known derive their energy from cooling magma (or recently solidified and hence still hot rock). These on the other hand, derive energy from reverse metamorphosis (normal metamorphic reactions goes like: low temperature rock ricn in water + heat + pressure => high presure,high temperature rock + free water . In this case the reaction runs the other way and water is bound to the rock and heat is liberated. This is only possible due to the fractures pressent in the sea floor allowing the water to come into contact with the olivine-containing rock. (i'm guessing, but it is most likely Dunite, a rock containing more than 90% olivine). The reaction 2 Mg2Si2O4 + 3 H2O => Mg3Si2O5(OH)4 + Mg(OH)2 liberates some heat and this heat (together with the water, leaches mineral out of the rock, these is then precipitated as the water cools as it exsits the seafloor. The minerals most easialy transported by low temperature fluids is carbonate minerals and quartz, but as quartz is not found together with olivine (reacts to form pyroxene) only the calcite is found. Thus the carbonate towers.
Yorus Yazeran
Plan: To go to Mars one day with a hammer
Then how do you explain Linux?? one of the most secure and stable operating systems avaliable..
Off topic i agree, but the fastest way to gain information and improove technology is by peer reveiw as in open source literature and science. Here anyone can test if the method is valid or the most efficient.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Except that in order for CO2 to become a liquid at all, you need an atmospheric pressure ABOVE that found here on earth (CO2 is 'dry ice' as it cannot exist in the liqid state unelss under pressure). If the beforementioned structures were to be verified as created by CO2-liquid, this would be a verry important and optimistic result, as the pressure on Mars vould have th have been much higher than today.
The structures found by the sattelites the past few years suggests that flowing water have existed on the surface of Mars in the past.
I hope it is still there (as some of the images returned have suggested, at least it was there some 10000 years ago), as this would make manned trips to Mars possible and practical.
Many landforms found on Mars have been made by flowing liquid (as they are so like those found on earth), and water is just the only plausible liquid avaliable on Mars.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
They even proved, that you cannot rectify random events like that (i think they calculated using random photons or something..) as this would create the beforementioned perpetum mobile.
Thus as far as saying, that this motor-protein uses brownian motion is wrong. In order to generate motion you have to utilize a energy-releasing reaction (e.g converting ATP to ADP). Some others got it ringt as they described how a surplus of protons is used as driving force.
That thermal motion is improtant, is no surprise though, all reactions (almost) require an activation energy to occour (even decomposition of nitroglycerin, although it is small indeed).
The discovery of this motor protein and how it works by converting a chemical gradient to mechanical work, is interesting however.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
If the US started to build apliances that saves energy (not to mention building cars that don't burn a gallon evry 10 miles) a lot of energy and CO2 could be saved).
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
It is right that the continents drift with an average speed of 4 cm/year, but it is only at the boundry-zones (like San-Andreas in California) that the shift is observed. Within the plates, there is no lateral shift of one city relative to one other. Neither is the coastline a plate boundry. The plate boundry between Africa and Europe is much further north (between Cypres and Tyrkey), therefore shift along this boundry cannot be responsible for this.
Vertical shifts on the other hand, vould be exspected and observed in any large river delta, due to the constant addition of fresh sediments.
These loads the underlying crust, and is responsible for slow subsidence (as observed at the Mississippi delta). The reson for subsidence due to addition of material is that the earth's crust is isostatically compensated, that is it 'floats' on the denser mantle.
Such downwarping of the continental edges at large river-deltas most likely has drowned a lot of prehistoric cities.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
If we want them to last and want people to see them, there is no other way.
Yours Yazeran
Plan: To go to Mars one day with a hammer
I only got to the testing phase, as i lost interest (plus the small problem with toasters and such turning on when i was not at home..) It only cost me a burned out parallelport, as i forgot some resistors in the first model.. a.k.a. Ooops!
Well at least learnt to include protective resistors between computers and home made stuff..
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Yours Yazeran
Plan: To go to Mars one day with a hammer!
You don't even have to do it at the subduction trenches, one could just as safely and effectively do it almost anywhere on the ocean floor (eccept the ocean ridges for obvious reasons), and the result would be the same.
The basalt in the ocean crust is a stable and dense rock, and if one vould like to be completely safe, use a small nuclear warhead among the waste, and detonate once the hole is sealed. This would create a ball of basaltic glass encapsulating the waste.
This would prevent release effectively even over geological timescales (and also prevent 'smart' people to try to dig the plutonium up again).
Yours Yazeran
Plan: To go to Mars one day with a hammer!
I once read (some 10 years ago) about how astronomers suddently discovered an astroid about 100 m in diameter as it was going away from the earth. Turned out it had passed within half the distance between earth and the moon, and they only found it after the close aproach.
If something that size hits a populated area (or ocean) then the toll in lives would be huge, as somethig that big would not airburst, but would penetrate the ground and create a crater at least 10 km wide. (not counting the firestorm and shockwave that propagate further out).
They didn't detect it before close aproach, as it was a rather dark object. One wonders how many other such objects is out there..
Yours Yazeran
Plan: To go to Mars one day with a hammer.
This is the one and most important reason for continuing space exploration! Earth isn't going to stick arround forever. So in order for the human race (or the race that exists at that time, (remember that the usual lifetime for a single species is roughly 2-4 milion years before it evolves into something different)) to survive ve have to spend time and effort into space exploration and space travel.
Yours Yazeran
Plan: To go to Mars one day with a hammer.
This is exactly what is beeing done in nuclear testings and similar (non nuclear) experiments.
Real artificial diamonds for cutting tools can be made this way (and are as far as i know as it is an inexpensive method)
Yours Yazeran
Plan: To go to Mars one day with a hammer.
Sadly Mr. Adams passed away this weekend.. He will me missed..
Yazeran
Plan: To go to mars one day with a hammer.
similarly, in Italy near Vesuvius (which blew up in AD. 79) ground movement in the sorounding area has been observed. Particularly near the town of Pozzuli which is situated above a magma-chamber. In the last 20 years the ground has been moving mostly upwards more than a meter! so that previously sunken Roman temples once again is above the water.
Yours Yazeran
Plan: To go to Mars one day with a hammer!
Well you could do that, there is only one small problem with that. Energy transportation is far from loss free. I dont have the figures, but i would estimate that more than 5% of the energy (electric) produced in europe is lost in the transmission lines.
In order for levelling like you suggest, by transporting the energy to where there is need for it,would increase the transport loss dramaticly.
Conversely, by pumping water, you only lose a small amount of the energy, as hydroelectric turbines and electric water pumps are wery energy efficient. (approx 1% loss as far as I recall) => aprox 2% loss in the combined cycle.
Yours Yazeran
Plan: to go to Mars one day with a hammer.
Well only if you use low voltage. Remember that P = U * I, and that resistance losses scale like I^2 * R.
Thus if you transform the power to high voltage, then you can drastically reduce the powerloss in the transmission lines. (This is the reason for the use of high voltage transmission lines on the ground). Modern high voltage cables (100kV+) dont have to be air-born (as in wires suspended between towers) but can be dug into the ground. theseare somewhat heawy, bur that is only due to the external insulation.
In the case of the cables discussed here, the external insulation is not nescesserry, as the power in the cable could be cut off in case of a kite dropping out of the sky.
Plan: to go to Mars one day with a hammer.
If the only definition of a liquid is that:
1) it lacks any long range order
2) it is isotropic (no changes in physcal properties with direction
3) it deforms plastically (i.e. flows; note no time scale given!)
then glass is a liquid. all glasses will deform given enough time. I'm not talking in minits here! Obsidian (wolcanic glass) do deform slowly over milions of years, Even at room temperature! Of couse it deforms much faster at elevated temperatures.
On the other hand, if a material deforms over time (like a candle or a glacier) does not mean that they too are liquids.
The problem here, is how we define a liquid. From the purely physical point of view, only the definition given in the beginning as well as a fourth one (thermodynamical one) is adequate:
4) liquids aquire internal thermodynamical equlibrium after a small temperature change
(irrespectively to wether or not the liquid state is the stable state, alas applies also for supercooled liquids)
All supercooled liquids posess a transition temperature (as noted in the article above) called 'the glass transition temperatre', below which the physical poperties change from a classical liquid to that of an other state where local internal equlibrium is not maintained (the glass state). In this sense glasses is not liquids, but belong to their own group of materials: the Glasses
The glass transition temperature is not constant, but changes with cooling rate, as slower cooling allows the liquid to maintain internal equlibrium to lower temperatures. There is a lower limit, however, as a liquid below the melting temperature cannot have lower internal energy (Gibbs' free energy) than the crystaline phase. (for more comprehensive study: refer to Solid state Chemistry and its Applications by Anthony R. West)
Well enough physics for today: the bottom line is, if a glass is above the glass transition temperature, then is IS a liquid, if it is below it is NOT.
Yours Yazeran
Plan: to go to mars one day with a hammer.
Actually the intermediate link you propose about the weather is correct. Recent discoveries by Eigil Friss-Christensen at Danish Space Research Institute indicates that there IS a correlation between solar activity (and sunspots) and mean temperature here on earth.
The correlation is that high solar activity and hence high solar wind density excludes some of the cosmic rays from the inner solar system.
The lack of comsmic rays then cause fewer clouds to condensate and fewer clouds results in higher temperatures.
(check here for a link to the publications on this subject; search for 'Friis-Christensen' to find the relevant ones).
Yours Yazeran
Plan: to go to Mars with a hammer some day
Nice to finally see someone who has some sense of perspective. The lake is only insulated for the last one milion years, and perhaps not even that.
Glacial ice moves, so does the antarctic ice sheet. Even though the lake has been covered by ice for over one milion yours, the just ice above the lake is most likely much yonger, and has thus contaminated the lake and 'reset' the lake at a later date.
The exact age of the ice obove the lake should be determinde as the drilling core reaches these parts of the ice, as one can count the years backwards from the surface (like counting year-rings in old trees)
The real interesting part from a geological and biological point of view (yep i'm a geologist) is if life exsists in the lake. Life can exsist at the bottom of the oceans (at the black smoker vents on East Pacific Rise at least) but if it can exsist in a almost frosen lake that has been isolated for 100.000+ years would be interresting to see.
plan: To go to Mars one day with a hammer..
Yazeran
I disagree. Most modern HTC's have a property called 'flux pinning'
Under high magnetic fields, the superconductor allows the magnetic field to recide in small 'tubes' within the superconductor. these tubes run through impurities in the ceramic, (which is non superconducting in any event) and is surrounded by supercurrents that keep the field lines in place.
as long as the circular currents is not so hing as to dissallow superconductivity, the bulk of the superconductor behaves as any normal one, that is it is superconducting.
This fenomenon is only found in the 'Type II' superconductors, but all the HighT ones belongs to this category (as far as i recall).
I disagree. Pegmatites are usually refered to as the last crystallized part of an igneous body (molten rock for the non geologists). Although many pegmatites do have huge crystals, they usually do not have such large open spaces as evident on the pictures. Furthermore, the location of the crystals in a silver and Zinc mine, suggests that the crystals have formed within a cavity created by flowing water (like Mammoth Caves in Kentucky) Furthermore, the mineralogy of the crystal cave in is not what you would expect from a regular pegamtite.
Normally pegmatites are formed form melts of the same composition as granite, so the prevalent minerals in pegmatites are usually Quarts, Feldspar and Biotite/Muscovite as well as more rare minerals as apatite and beryl. The crystals in the article is gypsum (CaSO4+2*H2O), which is not stable above 300C, which is incompatible with a molten origin
This IMHO proves that the crystal cave is not a pegmatite.
Having said that, i must admit i would like to se them up'n personal.. (too bad i live in Europe)