To: Mark Fox Msg #2234, Jun0194 23:20:00 Subject: Magnetic fields = Quoting Mark Fox to Da

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From: Rick Mcfarlane To: Mark Fox Msg #2234, Jun-01-94 23:20:00 Subject: Magnetic fields -=> Quoting Mark Fox to David Rice <=- DR> Mark claimed that the Earth's magnetic field is "decaying," when DR> in fact it is not. MF> 1835...8.558 x 102 amps per meter MF> 1945...8.065 x 102 amps per meter MF> 1965...8.017 x 102 amps per meter It's getting smaller, alrighty. MF> Measuring by a consistent rate, the magnetic rate it is declining MF> at a half life rate of 830-1400 years (26 nanoteslars per year)-- MF> half life every 830 (Magstat)-1400 years (Barnes). Unstated assumption alert! Any evidence at all that this is a decay phenomenon? MF> At this rate it MF> will be ineffective in a few thousand years. Using P=RI, since MF> the resistance of rock would be a constant (R), Power generated would MF> be millions of times greater just 10,000 years ago as current (I) MF> increases arrhythmically. 10,000 years ago the planet would have been MF> to hot to sustain life. Oh, Mark, the planet is much less than 10,000 years old, but it started off very cold, not very hot. Consider: Feb. 20, 1994, -15 C March 30, 1994, -1 C May 31, 1994, +5 C (Above observations are nighttime low temperatures at my home locale, Goulais River, Ontario, Canada.) Obviously, the tempreature has been rising rapidly. Probably due to the sun heating the planet. In the last 100 days the nighttime low has gone up by 20 Celcius degrees. At that rate, the nighttime low will be above the boiling point in 450 days, and all life will be destroyed. Going the other direction, the nighttime low was less than absolute zero (-273 C) about 1400 days ago. Since less than absolute zero is an impossibility, obviously, the earth is only about 4 years old. Silly? Of course. But your argument is just as silly. There's lots of evidence that the magnetic field of the earth varies in both direction, not just down. Take a look, before you make yourself look even sillier. And there is certainly no evidence that it is "decaying" with any kind of a "half-life" at all. A linear approximation would fit through those three points you stated just as well as the exponential curve you chose. Next, a word about extrapolation: Ask any statistician (you can start with me, if you'd like) whether he considers it safe to fit a straight line to 130 years of data, and then extrapolate it 10,000 years into the past. He'll laugh his head off. Then ask him if an exponential curve would be safer. You'll have to scrape him off the floor! Extrapolating at all is dangerous (without good theoretical proof that you have the right curve). The farther you extrapolate, the more dangerous it is. I can't imagine anyone seriously extrapolating more than the range of the base data, under any circumstances. You just extrapolated 70 times that far. And all of this applies to a straight line, which is a well behaved curve. An exponential decay curve is very ill behaved (unless it really is a decay phenomenon). Actually, your argument is even sillier than mine. I used a straight line, and extrapolated 14 times the range of my base data (a ludicrous thing to do). You used a very ill-behaved curve (exponential) and extrapolated 70 times the range of your base data (an incredibly humourous thing to do!) MF> Time will tell the correct model. Come on, Mark. I read your posts accusing others around here of intellectual dishonesty. Now it's time to check your own. The above argument is so ludicrous, so contrived, that it qualifies 100% for that same label. It is clearly devised to "get the right answer", and it does so by making unwarranted assumptions, and brutally dangerous extrapolations. Think it over. Do you still maintain this is a good argument? That it has any validity at all? Show us YOUR intellectual honesty. MF> Cosmic dust theory--there are particles of dust that settle to the MF> earth, and moon all the time. Patterson of the Swedish Oceanographic MF> Institute calculated that 14 million tons of meteoritic dust settles on MF> the earth year as a fine powder. (Such dust can be calculated and MF> eliminating the terestrial sorces based on the nickel content.) The amount of meteoric dust in space can also be observed in space. And it has been. With no need to try correct for terrestrial contamination. Why not quote those studies? Because they don't support your point of view, perhaps? Back to the honesty question. Instead, you reference terrestrial studies: MF> filled in? Hans Petersson, COSMIC SPHERICALS AND METEORITIC DUST, MF> Scientific American p 202, February 123. What year was that? 1960? And: MF> --Gold, ROYAL ASTRONIMICAL SOCIETY OF MF> LONDON, Monthly notic 115:585 1955 p 598. Earth based studies from a period when access to space was impossible. We've got better, more recent data, but you insist on quoting the old, inaccurate ones. Why would that be? MF> Pattersons, it would be closer to 630 centemeters. NASA's best MF> calculations led them to believe that lots of dust should be on the MF> moon when they landed on the moon (hence the big saucer feet on the MF> ship). NASA had been to the moon (remember Surveyor?) before the Eagle landed. They knew from direct experience how much dust there was there when they designed those feet. They may have had some concern about dust of lunar origins (caused by thermal spalling, and the impact of meteors), but they knew full well that the amount of meteoric dust would be very small. MF> Dust was only inches deep suggesting an age of 8,000 yrs or MF> less. You have a source for this observation? NASA you say? Must be, they're the only ones who've been there. Let's see if I got this straight. You go to NASA for space based observations on how much dust there is on the moon, but you forget to ask them how much dust they have observed in space (ie. the rate at which dust will collect on the moon?). And having forgotten to ask them, you go looking through 40 year old issues of Scientific American for a source of data? Do I look that credulous? This isn't just an honest oversight. You know where good data can be obtained, yet you ignore it in favour of outdated inaccurate data. Why? Back to that intellectual honesty question again. You question the intellectual honesty of others (possibly quite rightly, I don't know), but you aren't demonstrating a whole lot of it here yourself. Take care.


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