I thought they established that there isn't going to be a Big Crunch. They found that the expansion of the universe is accelerating, not decelerating. Am I working with old news here? Has that been disproven already? (I turn my head for a few minutes of Diablo 2, and they change the fate of the universe on me.)
I thought about that yesterday as I was working out. We were having two completely different arguements and it's no wonder we didn't agree. Yes, I was looking at it from a point of view of equilibrium, while you're assuming that the core is still coming up to temperature. In that case, yes, I can see how the core could be cooler than the heating layers. But I don't see how you can say the center will NEVER be hotter than the heating layers. (Thermo was a LONG time ago, lemme think for a minute...) I guess that's in the same way that it can never be cooler than the heating layers. (Once it's at equilibrium.) This is if the rocky center produces NO heat. If it produces any, than the core would have to be warmer once it reaches equilibrium. Maybe much warmer. (You mentioned that rock is kind of a lousy conductor of heat.)
I think you do see my coffee point, you're just dismissing it. I think we agree that flexing water will produce less heat than flexing rock the same amount. I think we agree that any seas on Europa get flexed more than the rock. (Just because it's more maleable, less friction as it's rubbed against itself, therefore has less flex-resistance.) We're disagreeing on two points: first, my thing is that the very quality of water that makes it flex more (lower viscosity than rock) is the same quality that makes it produce less heat when it is flexed. You're arguing that its resistance to flexing is disproportionatly lower than the heat produced by that resistance. It seems to me that the two would be proportional. Granted, this isn't my field of study, so I'm going on intuition here. Do you know of any web sites or references you can point me at? The second point that makes me doubt that the majority of the heating comes from the water/ice layer is a matter of scale. Europa has a radius of over 1500km. They talk in terms of oceans being tens of km deep. I grant you that the rock isn't flexing as much as the oceans, but there's SO much more rock than water. Which I guess brings us back to point one.
You confuse me by comparing Jupiter to Earth. . . Oh, wait, did you mean to say that Jupiter is so much bigger than our moon? Yeah, I understand that, and I get that there isn't nearly the tidal energy on Earth that there would be on Europa, but there should at least be a thoretical (if not measured) number of BTUs that Earth tides produce. Seeing that number might help me understand the scale we're talking about here.
As for the Volcanos, ok. I can accept that.
"You refuse to believe the current research because of your intuition"? Dude, all I have to go on is my intuition. You haven't pointed me towards one piece of research. "Nothing I can present will ever convince you otherwise, we should drop this"?!? You've presented ideas without backing them up with ANYTHING solid. You've mentioned computer simulations without mentioning one formula, algorythm, or web site. Show me anything published! Send me a link to your officemate's web site! (Sorry if I'm flying off the handle here, but people who ignore evidence in favor of their pre-concived notions are a pet peeve of mine. Implying that I'm one of those people hit a tender spot.) By far, the most interesting discussions I've had are ones that've refuted long-standing misconceptions of mine. I'd sincerely like you to reply with some references, or formulae for some of these math models you keep mentioning. On the other hand, if you're just going to post an "I'm right and you're wrong, just accept that" message or another insult to my intelligence, then I agree we should drop this.
Ulgh. This is the last time I post anything before having my morning coffee.
Ok, first off, you keep side stepping the whole "Heat flows from warmer stuff to cooler stuff." I'd like you to explain how. If you have a ball, and the outer layers are a certain temperature, how can the inside be cooler? In order for that to be true, the heat that collects in the center has to magically disipate without going into the outer layers.
Second, the first few meters of Earth are cooler than the air because it's spring. If I do the same experiment in six months, I'll get exactly the opposite result. Everywhere I've gone caving, the cave is pretty much the average of the year round temperature there. That's why the inside of Mammoth cave is warmer than caves in Indiana. Now, if you go deeper, say a few hundred meters, then it starts getting warmer. (Because the inside of Earth is warmer than the outside. Otherwise, the core wouldn't be cooling any more.)
Your second paragraph: You say you have computer models that say you're right. Well, ok, I guess I have to concede this one. But I'm still not convinced. The implication almost seems to be that I can heat my coffee by stiring it vigorously. How much heat do Earth's tides produce? (I realize that since the moon takes 28 days to orbit once, and we're so far away from the sun, Earth's tides wouldn't produce NEARLY as much heat as Europa's, but I've never heard of it producing anything measurable.)
Your third paragraph: Again, how can the center be cooler than the water? If the center is cooler than the water, some heat is going to flow from the water to the center. Middle school physics. That can't happen forever, because once the heat is in the center, it's got nowhere to go except back into the water, and it's not going to do that until the center is warmer than the water. Even if all the moon's heat is produced in the seas, the center has to be AT LEAST as warm as the water. What research have you done that implies otherwise?
And I'll say it again, the article mentions volcanos. That implies temperatures much higher than 100C. Is the article in error about that?
I realize that the ice can flex independently of the inner layers of the moon, that's why I don't think the system as a whole gets much of its heat from there. And I realize the water probably flexes the most, but the flexing isn't what causes heat. It's the resulting friction of things rubbing together as they're flexed. If you take a zip-lok filled with water, knead it all you want, you're not going to produce much heat. Rub two pieces of sand paper together, and it'll get pretty warm pretty quick.
Now, I don't understand what you mean by "disipating heat". If you're talking about the moon as a whole, the only part that can disipate any heat at all is the surface ice. (That's the only way for heat to escape the system into space.) Now, if by that phrase you mean "distributing heat", well even if the ice sheet does take the brunt of the heating (Which I'm not convinced of. See above paragraph.) the core has to be at least as warm as the water for the system to be at equilibrium. (If the water is warmer than the rock, SOME heat is going to flow into the rock. Maybe only a small percentage, but some. As long as the core is cooler than the water, heat will always flow in that direction. Once the core is warmer than the water, it can start venting heat away, but not before.) As for it not being clear that the core or mantle heat up in any significant way, well, the article talks about volcanos. If they mean molten rock volcanos, then I'm willing to bet that the inside is warmer than liquid water or water ice.
And I sincerly doubt that the icy outer layer is the warmest. In every situation I can think of, liquid water is warmer than water ice.
So the kneading is a recent thing. I didn't know that. Interesting.
As for it not happening in the core, "since tidal forces are proportional the the diameter of the layer". . . yeah, but to produce heat through friction, aren't we talking about the difference in tidal forces between layers? If you take a ball of bread dough and pull it into a 3d elipse (whatever that shape is called), the core gets pushed around too. I guess I see your point, in that it doesn't JUST happen in the core. It's more of a distributed thing. But the core would still be the hottest part of the moon, because heat disappates through the surface. And I doubt that the flexing ice produces much of the moon's heat. (That's the layer that radiates heat into space, and liquid water would be warmer than ice, so heat would flow the other way.) I guess when I said "core" I was thinking "rocky part" which isn't quite accurate.
We already went through all this when they mentioned crashing Galileo into Jupiter. They have decontamination procedures, they just didn't think to use them on Galileo. I can only assume that if they're going to trash a probe rather than risk contamination, they'll just sterilize the Europa probe.
A clarification, Europa's core is heated by the gravity fields of Jupiter and other big moons. (Is Io a Jupiter moon?) The result is kind of like tides on Earth, but with the moon's rocky core. As it gets kneaded like dough, the friction gives off heat. Assuming that this has been happening since it formed, refering to the core as "still hot" is accurate. (If a little misleading.)
A lot of people have posted talking about how we're contaminating Jupiter instead of Europa. Look, it's like this. Even if there's life on Jupiter, EARTH bacteria can't live there. If there's life on Europa, it may be an environment that Earth bacteria could live in. And then it would be contaminated with Earth life. It's not that Jupiter is any less important, it's that we CAN'T contaminate Jupiter, so it's a safer place to send Galileo.
Actually, they think it might have liquid water under the ice. That pretty much limits the internal temperature between 0c and 100c. Earth bacteria doesn't have much trouble surviving in that kind of temperature flux.
"the odds are astounding." And which numbers are you talking about? People's ideas of unbelievable seem to be based on how far things are from human everyday. God didn't make the universe from a human perspective. I'll bet to him 4.5 billion years is a perfectly reasonable amount of time. But nothing in a human life lasts that long, so we have trouble believing it. From what I've read, dormant bacteria can last almost indefinitly. That combined with the evidence we have that coal does take millions of years to form, and we've got a really cool example of bacteria survivability. Don't get me wrong, I think we should always CONSIDER that we've got it wrong. (The biggest advances in science have been discovering something we've screwed up.) But all the evidence should be looked at without our preconceptions of what's normal.
You're assuming the Big Bang happened in a PLACE. It didn't. Or rather, it did and that place would be the entire universe. Basically, all points of the universe were created at the Big Bang. (They're just a lot farther apart now.) The BB happened here, and the light from that is long gone. The BB also happened in the Andromeda galaxy, and the light from that has also passed us a LONG time ago. But the light from the BB from locations (AGE_OF_UNIVERSE) light years from here is just now reaching us. (That's the microwave background. Started off as gamma rays, but, you know, redshift, Hubble Expansion.) Actually, with Hubble Expansion, if something's (AGE_OF_UNIVERSE) light years from us now, it was closer to us when the universe became transparent. So we'd actually be getting light from objects farther away than that, wouldn't we? Ouch. Physics headache.
Yeah, the body efficiantly converts energy, but it converts it to stuff like, kinetic energy (motion) of blood, and firing nerve impules a few billion times a minute to complete a thought. Not exactly harvestable. If you crunch the numbers, it's much easier to take all the food you would've fed the guy, and burn it in a controlled furnace.
Dude, get out from under your rock. What we're talking about has nothing to do with airport security. We're talking about the bill that just got passed by the senate that would allow the FBI to tap your internet communications for up to 48 hours without a warrant. (Go look up the 4th Amendment.) And the thing congress is looking at about requiring all encryption software to have a back door for the government to use. If that sounds fine to you (along with giving the FBI a copy of your house key, just to have on file), think about your bank using that. All it would take is one hacker, and a portion of net traffic would suddenly be insecure. How about the suggestion that every citizen be required to carry a federal ID card? (Papers, please.) Bringing American airport security up to the global standard isn't infringing on anybody's personal liberties.
Slashdot Mirror
I thought they established that there isn't going to be a Big Crunch. They found that the expansion of the universe is accelerating, not decelerating. Am I working with old news here? Has that been disproven already? (I turn my head for a few minutes of Diablo 2, and they change the fate of the universe on me.)
No, no, the bad guys are all fighting each other. Notch one up for us.
And now www.petswarehouse.com is being slashdoted. We'd all better find some good lawyers.
I thought about that yesterday as I was working out. We were having two completely different arguements and it's no wonder we didn't agree. Yes, I was looking at it from a point of view of equilibrium, while you're assuming that the core is still coming up to temperature. In that case, yes, I can see how the core could be cooler than the heating layers. But I don't see how you can say the center will NEVER be hotter than the heating layers. (Thermo was a LONG time ago, lemme think for a minute...) I guess that's in the same way that it can never be cooler than the heating layers. (Once it's at equilibrium.) This is if the rocky center produces NO heat. If it produces any, than the core would have to be warmer once it reaches equilibrium. Maybe much warmer. (You mentioned that rock is kind of a lousy conductor of heat.)
I think you do see my coffee point, you're just dismissing it. I think we agree that flexing water will produce less heat than flexing rock the same amount. I think we agree that any seas on Europa get flexed more than the rock. (Just because it's more maleable, less friction as it's rubbed against itself, therefore has less flex-resistance.) We're disagreeing on two points: first, my thing is that the very quality of water that makes it flex more (lower viscosity than rock) is the same quality that makes it produce less heat when it is flexed. You're arguing that its resistance to flexing is disproportionatly lower than the heat produced by that resistance. It seems to me that the two would be proportional. Granted, this isn't my field of study, so I'm going on intuition here. Do you know of any web sites or references you can point me at? The second point that makes me doubt that the majority of the heating comes from the water/ice layer is a matter of scale. Europa has a radius of over 1500km. They talk in terms of oceans being tens of km deep. I grant you that the rock isn't flexing as much as the oceans, but there's SO much more rock than water. Which I guess brings us back to point one.
You confuse me by comparing Jupiter to Earth. . . Oh, wait, did you mean to say that Jupiter is so much bigger than our moon? Yeah, I understand that, and I get that there isn't nearly the tidal energy on Earth that there would be on Europa, but there should at least be a thoretical (if not measured) number of BTUs that Earth tides produce. Seeing that number might help me understand the scale we're talking about here.
As for the Volcanos, ok. I can accept that.
"You refuse to believe the current research because of your intuition"? Dude, all I have to go on is my intuition. You haven't pointed me towards one piece of research. "Nothing I can present will ever convince you otherwise, we should drop this"?!? You've presented ideas without backing them up with ANYTHING solid. You've mentioned computer simulations without mentioning one formula, algorythm, or web site. Show me anything published! Send me a link to your officemate's web site! (Sorry if I'm flying off the handle here, but people who ignore evidence in favor of their pre-concived notions are a pet peeve of mine. Implying that I'm one of those people hit a tender spot.) By far, the most interesting discussions I've had are ones that've refuted long-standing misconceptions of mine. I'd sincerely like you to reply with some references, or formulae for some of these math models you keep mentioning. On the other hand, if you're just going to post an "I'm right and you're wrong, just accept that" message or another insult to my intelligence, then I agree we should drop this.
Ulgh. This is the last time I post anything before having my morning coffee.
Ok, first off, you keep side stepping the whole "Heat flows from warmer stuff to cooler stuff." I'd like you to explain how. If you have a ball, and the outer layers are a certain temperature, how can the inside be cooler? In order for that to be true, the heat that collects in the center has to magically disipate without going into the outer layers.
Second, the first few meters of Earth are cooler than the air because it's spring. If I do the same experiment in six months, I'll get exactly the opposite result. Everywhere I've gone caving, the cave is pretty much the average of the year round temperature there. That's why the inside of Mammoth cave is warmer than caves in Indiana. Now, if you go deeper, say a few hundred meters, then it starts getting warmer. (Because the inside of Earth is warmer than the outside. Otherwise, the core wouldn't be cooling any more.)
Your second paragraph: You say you have computer models that say you're right. Well, ok, I guess I have to concede this one. But I'm still not convinced. The implication almost seems to be that I can heat my coffee by stiring it vigorously. How much heat do Earth's tides produce? (I realize that since the moon takes 28 days to orbit once, and we're so far away from the sun, Earth's tides wouldn't produce NEARLY as much heat as Europa's, but I've never heard of it producing anything measurable.)
Your third paragraph: Again, how can the center be cooler than the water? If the center is cooler than the water, some heat is going to flow from the water to the center. Middle school physics. That can't happen forever, because once the heat is in the center, it's got nowhere to go except back into the water, and it's not going to do that until the center is warmer than the water. Even if all the moon's heat is produced in the seas, the center has to be AT LEAST as warm as the water. What research have you done that implies otherwise?
And I'll say it again, the article mentions volcanos. That implies temperatures much higher than 100C. Is the article in error about that?
I realize that the ice can flex independently of the inner layers of the moon, that's why I don't think the system as a whole gets much of its heat from there. And I realize the water probably flexes the most, but the flexing isn't what causes heat. It's the resulting friction of things rubbing together as they're flexed. If you take a zip-lok filled with water, knead it all you want, you're not going to produce much heat. Rub two pieces of sand paper together, and it'll get pretty warm pretty quick.
Now, I don't understand what you mean by "disipating heat". If you're talking about the moon as a whole, the only part that can disipate any heat at all is the surface ice. (That's the only way for heat to escape the system into space.) Now, if by that phrase you mean "distributing heat", well even if the ice sheet does take the brunt of the heating (Which I'm not convinced of. See above paragraph.) the core has to be at least as warm as the water for the system to be at equilibrium. (If the water is warmer than the rock, SOME heat is going to flow into the rock. Maybe only a small percentage, but some. As long as the core is cooler than the water, heat will always flow in that direction. Once the core is warmer than the water, it can start venting heat away, but not before.) As for it not being clear that the core or mantle heat up in any significant way, well, the article talks about volcanos. If they mean molten rock volcanos, then I'm willing to bet that the inside is warmer than liquid water or water ice.
And I sincerly doubt that the icy outer layer is the warmest. In every situation I can think of, liquid water is warmer than water ice.
So the kneading is a recent thing. I didn't know that. Interesting.
As for it not happening in the core, "since tidal forces are proportional the the diameter of the layer". . . yeah, but to produce heat through friction, aren't we talking about the difference in tidal forces between layers? If you take a ball of bread dough and pull it into a 3d elipse (whatever that shape is called), the core gets pushed around too. I guess I see your point, in that it doesn't JUST happen in the core. It's more of a distributed thing. But the core would still be the hottest part of the moon, because heat disappates through the surface. And I doubt that the flexing ice produces much of the moon's heat. (That's the layer that radiates heat into space, and liquid water would be warmer than ice, so heat would flow the other way.) I guess when I said "core" I was thinking "rocky part" which isn't quite accurate.
We already went through all this when they mentioned crashing Galileo into Jupiter. They have decontamination procedures, they just didn't think to use them on Galileo. I can only assume that if they're going to trash a probe rather than risk contamination, they'll just sterilize the Europa probe.
A clarification, Europa's core is heated by the gravity fields of Jupiter and other big moons. (Is Io a Jupiter moon?) The result is kind of like tides on Earth, but with the moon's rocky core. As it gets kneaded like dough, the friction gives off heat. Assuming that this has been happening since it formed, refering to the core as "still hot" is accurate. (If a little misleading.)
A lot of people have posted talking about how we're contaminating Jupiter instead of Europa. Look, it's like this. Even if there's life on Jupiter, EARTH bacteria can't live there. If there's life on Europa, it may be an environment that Earth bacteria could live in. And then it would be contaminated with Earth life. It's not that Jupiter is any less important, it's that we CAN'T contaminate Jupiter, so it's a safer place to send Galileo.
Actually, they think it might have liquid water under the ice. That pretty much limits the internal temperature between 0c and 100c. Earth bacteria doesn't have much trouble surviving in that kind of temperature flux.
"the odds are astounding." And which numbers are you talking about? People's ideas of unbelievable seem to be based on how far things are from human everyday. God didn't make the universe from a human perspective. I'll bet to him 4.5 billion years is a perfectly reasonable amount of time. But nothing in a human life lasts that long, so we have trouble believing it. From what I've read, dormant bacteria can last almost indefinitly. That combined with the evidence we have that coal does take millions of years to form, and we've got a really cool example of bacteria survivability. Don't get me wrong, I think we should always CONSIDER that we've got it wrong. (The biggest advances in science have been discovering something we've screwed up.) But all the evidence should be looked at without our preconceptions of what's normal.
Yeah, but I think the important thing here is that EARTH bacteria couldn't survive there, whereas they might survive on Europa.
"Freedom is just a pretty word, fight for liberty.." Huh? Pardon my illiteracy, but what's the difference?
I guess they don't want anyone to write about Bill Gates.
Yeah, but wouldn't the transmit time of sound through water be a lot more constant than that of packets through different internet paths?
Obviously? Well, it's behaving like other Microsoft final products.
??? What percentage of virus writers have ideological or political reasons?
You're assuming the Big Bang happened in a PLACE. It didn't. Or rather, it did and that place would be the entire universe. Basically, all points of the universe were created at the Big Bang. (They're just a lot farther apart now.) The BB happened here, and the light from that is long gone. The BB also happened in the Andromeda galaxy, and the light from that has also passed us a LONG time ago. But the light from the BB from locations (AGE_OF_UNIVERSE) light years from here is just now reaching us. (That's the microwave background. Started off as gamma rays, but, you know, redshift, Hubble Expansion.) Actually, with Hubble Expansion, if something's (AGE_OF_UNIVERSE) light years from us now, it was closer to us when the universe became transparent. So we'd actually be getting light from objects farther away than that, wouldn't we? Ouch. Physics headache.
Red color? Redshift from Hubble Expansion.
"Increasingly unlikely constructions"? You mean like a universe ruled by electromagnetically active plasmas?
Yeah, but then you'd erase all the protected files. This isn't so much a computer protection thing as a file protection thing.
Yeah, the body efficiantly converts energy, but it converts it to stuff like, kinetic energy (motion) of blood, and firing nerve impules a few billion times a minute to complete a thought. Not exactly harvestable. If you crunch the numbers, it's much easier to take all the food you would've fed the guy, and burn it in a controlled furnace.
How did he get his hands on one? The article said they were going to start producing them in October.
Dude, get out from under your rock. What we're talking about has nothing to do with airport security. We're talking about the bill that just got passed by the senate that would allow the FBI to tap your internet communications for up to 48 hours without a warrant. (Go look up the 4th Amendment.) And the thing congress is looking at about requiring all encryption software to have a back door for the government to use. If that sounds fine to you (along with giving the FBI a copy of your house key, just to have on file), think about your bank using that. All it would take is one hacker, and a portion of net traffic would suddenly be insecure. How about the suggestion that every citizen be required to carry a federal ID card? (Papers, please.) Bringing American airport security up to the global standard isn't infringing on anybody's personal liberties.