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Iron Age Potters Accidentally Recorded the Strength of Earth's Magnetic Field (npr.org)
Solandri writes: We've only been able to measure the Earth's magnetic field strength for about two centuries. During this time, there has been a gradual decline in the field strength. In recent years, the rate of decline seems to be accelerating, leading to some speculation that the Earth may be losing its magnetic field -- a catastrophic possibility since the magnetic field is what protects life on Earth from dangerous solar radiation. Ferromagnetic particles in rocks provide a long-term history which tells us the poles have flipped numerous times. But uncertainties in dating the rocks prevents their use in understanding decade-scale magnetic field fluctuations.
Now a group of archeologists and geophysicists have come up with a novel way to produce decade-scale temporal measurements of the Earth's magnetic field strength from before the invention of the magnetometer. When iron-age potters fired their pottery in a kiln to harden it, it loosened tiny ferromagnetic particles in the clay. As the pottery cooled and these particles hardened, it captured a snapshot of the Earth's magnetic field. Crucially, the governments of that time required pottery used to collect taxed goods (e.g. a portion of olive oil sold) to be stamped with a royal seal. These seals changed over time as new kings ascended, or governments were completely replaced after invasion. Thus by cross-referencing the magnetic particles in the pottery with the seals, researchers were able to piece together a history of the Earth's magnetic field strength spanning from the 8th century BCE to the 2nd century BCE. Their findings show that large fluctuations in the strength of the magnetic field over a span of decades are normal. The study has been published in the journal PNAS.
Now a group of archeologists and geophysicists have come up with a novel way to produce decade-scale temporal measurements of the Earth's magnetic field strength from before the invention of the magnetometer. When iron-age potters fired their pottery in a kiln to harden it, it loosened tiny ferromagnetic particles in the clay. As the pottery cooled and these particles hardened, it captured a snapshot of the Earth's magnetic field. Crucially, the governments of that time required pottery used to collect taxed goods (e.g. a portion of olive oil sold) to be stamped with a royal seal. These seals changed over time as new kings ascended, or governments were completely replaced after invasion. Thus by cross-referencing the magnetic particles in the pottery with the seals, researchers were able to piece together a history of the Earth's magnetic field strength spanning from the 8th century BCE to the 2nd century BCE. Their findings show that large fluctuations in the strength of the magnetic field over a span of decades are normal. The study has been published in the journal PNAS.
From TFA: ''' "When dealing with such large-scale phenomena, we don't usually think it can occur within a few decades. We usually think it would take thousands or tens of thousands of years," Forman says. The finding, he adds, "opens up a big can of worms" because researchers just don't know how or why that would happen. So there's something missing about scientists' concept of goings on in the Earth's core.''' But hey, at least now we know we don't know :)
+Raider of the lost BBS
How do we boost the strength far enough to eliminate cancer?
Pretty nifty.
I'm a bit miffed about language: "[...] it loosened tiny ferromagnetic particles in the clay. As the pottery cooled and these particles hardened, [...]"
That's a pretty graphic description, but in a geek site... can't we just say Curie point, or Curie temperature?
If we don't keep the standards, who will?
(If you think some jargon is exclusive: insert a link to Wikipedia -- there's, as often, a very nice article on that).
The large variation in results for the magnetic fields is the creation stage of the pottery was done in completely uncontrolled circumstances.
Isn't this actually Paleomagnetism/Archaeology 101? I mean, reconstructing the magnetic field in shape and strength from the finds is a substantial endeavor, but the headline itself is no news to anyone in the field. It's been one of the bog-standard methods of how archaeological sites are surveyed.
Ezekiel 23:20
Just a thought
Build a Man a Fire, and He'll Be Warm for a Day. Set a Man on Fire, and He'll Be Warm for the Rest of His Life.
Language, folks. Accidents are things you want to avoid, not things you just don't realize.
So... If the magnetic field protects us from solar radiation, and the magnetic field is in a period of decline, and we're seeing a period of warming....
. . . . back in my Geophysics days (early 1980s), we already knew that the current planetary magnetic field was in decline, and we were approaching a pole reversal "real soon now" (in Geologic timeframe, not human timeframe. . ).
Heck, we were routinely measuring fossilized magnetic remnant fields in far older rocks, not just strength, but orientation as well. And finding the proper orientation of the sample was always difficult, generally required microscopic examination of a thin slice of the sample. The advantage of pottery for recent sampling, is that it is far easier to determine the orientation of the sample. . .
The magnetic field redirects all of the Earth-bound solar radiation near the poles where it creates auroras, and people/life there aren't dying of radiation.
"... to some speculation that the Earth may be losing its magnetic field -..."
Since the data ultimately suggests that fluctuations are completely normal, I submit that this also starts to explain why people are taking scientists less and less seriously.
I suspect that the cadre of researchers crying that the sky was falling was probably a small percentage, yet because of the synergies of such predictions, commercial media, & natural human histrionics, THIS was the narrative being discussed in the broader discourse.
Cf the Cry Wolf syndrome
-Styopa
There are a lot of red brick houses in the world. If only the date of the building of the house is known and the bricks are not repurposed from other buildings, similar information can be derived.
If they can measure the magnetic properties of the mortar you can even get the direction.
Hmm ... How are you going to determine field orientation at time of cooling below the Curie temperature for pottery? Wouldn't that require knowing the physical orientation of the item when it was being cooled after firing? Am I missing something, like there's a universal point-to-the-east orientation that all pottery is placed in when cooling?
I can see making a good guess for geological structures, but pottery?
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
Since the magnetic field is declining, and losing our magnetic field would be catastrophic for life on Earth, we must therefore answer the two part question:
How is human activity causing this, and how much tax must we impose in order to make it stop?
Looks like you hired cheap labor that simply threw the magnetic rocks in a bag which is why you had problems later. Our rock collectors are more expensive but they note full orientation of the sample (all 3 degrees-of-freedom, compared to 2 for pottery where you only know the direction of "up").
How does the change in mag field strength jive with warming or cooling of Earth? Does the extra solar radiation heat us any?
This wasn't an accident, that was inadvertent.
Let's tax something!
They may have recorded it inadvertently, not accidentally.
Accidentally means you were trying to avoid doing it but it happened.
Inadvertently means you did so without knowing because it was not your focus.
Alexander Fleming accidentally left out a Staphylococcus plate culture and inadvertently discovered penicillin.
English is a wonderful language full of very precise words so let's use them accurately!
Anons need not reply. Questions end with a question mark.
Well, assuming you know the shape of the original pottery, or better still, have a whole piece or enough to reconstruct: simply MEASURE the orientation, then use paleomagnetic detection techniques to measure the remnant field. Then compare the observed field orientation against the physical orientation of the sample
We need a new protocol that redistributes money from wealthy countries to poor ones who will be most affected by the loss of the magnetic field because the wealthy ones have a lot more electric motors and refrigerator magnets so they're ruining the Earth's field.
Before Common Era? WTF? As opposed to an "uncommon" one?
OK, I'm a (kinda) scientist, so I should maybe be "against" all the religious stuff, but I have no problem with "Before Christ" just as I have no problem with V for Volt(a) or A for Ampere. (Grant you, these were real people, and real scientists too...)
FFS, it's not like "BC" is insulting to Muslims or other people who use a different calendar (many also religion-based), since they're not aligned with the same time period. /rant
If anything, "BCE" seems more insulting, since it implies that their alternative calendars are "not common"...
I can't help but wonder if Earth really is going to shit soon and they are discrediting every natural-based doomsday phenomena. You get the head of EPA not believing in global warming and now scientists keep trying to put minds at ease regarding things like this, more so going out of their way now than ever, and it's really weird. They even have areas in the U.S. that somehow have been determined unfloodable and those some areas are the ones where electronic communication doesn't work and lots of construction going on and creating Blackfeet oil lines for god knows what. They've also tried to discredit Canada for harboring "pirated content," but that's exactly the same place the EPA started uploading all they had before Trump went into office and other organizations did as well.
The quote: "Their findings show that large fluctuations in the strength of the magnetic field over a span of decades are normal."
Well, no shit, Sherlock. I'd like to add the corollary:
"Their findings show that large fluctuations in the strength of the climate over a span of decades are normal."
And you know that the pottery wasn't moved from its original orientation during cooling because .... ?
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
It's called "virtue signaling" It is defined as:
It is designed to show that writer imagines himself teddibly teddibly important and above, far above, the hoi polloi. He wouldn't dare to presume even the hint of a personage known as Christ because, well, because it is just too teddibly gauche.
"Christ" is a title (meaning messiah), not a name. AD is similar in that "D" stands for Domini (Latin for Lord). So both BC and AD express a Christian belief about Jesus.
BCE/CE has been a standard in discussing historical time periods for a while now. There's nothing impolite about it, just as there's nothing impolite about using Before Christ/Anno Domini, or using a Hebrew calendar, or using a Chinese calendar, or using an Islamic calendar, or a Hindu one, etc.
Possibly because it might be a little too hot to move...what would be the purpose of moving pottery before it cools?...well I guess the could have made a kiln on a wagon...or...a spinning kiln...hmmm...
It's not like this is a new thing. And it really doesn't matter in ordinary conversation, at least for most of us. But when publishing in the Proceedings of the National Academy of Science, it makes sense to use the terminology of science, which does not recognize Jesus as "Christ" with all of the associated baggage.
[1] http://www.todayifoundout.com/...
...nightmare...
church of the better resurrection... https://betterresurrectionchurch.wordpress.com/
In america! :)
Not in the rest of the world.
It makes no sense to give a certain point in time a different name depending if you refer to it 'before' or 'after'.
Evereyone, except americans, is saying before _christ_ and after _christ_.
That means we say AD or AC and BC. The american nomenclature is just confusing
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
But when publishing in the Proceedings of the National Academy of Science, it makes sense to use the terminology of science, which does not recognize Jesus as "Christ" with all of the associated baggage.
I think more to the parent's point, It seems a bit idiotic to claim the intent of not recognising any particular religion in scientific language by using BCE/CE over BC/AD because it drops the word "Christ", while at the same time keeping and still using as starting points the date of the birth/death of Jesus Christ.
It's literally saying that because science is secular, it must avoid the favouring religions and will still use the birth/death of a religious figure for the basis of their calendar, but it's ok because they will use a different NAME for the date than had been historically in use because that name happened to reference the religious figure upon which it is centered.
I doubt that science recognizes mythological creatures, yet the IAU requires newly discovered solar system objects to be named after them. So before some scientists push for terminology change such as "BCE", they might want to convince other scientists to stop introducing new names such as "Makemake" first.
There are courts in the US where witnesses are typically sworn in on a Bible, so help them God. They can also choose to affirm with no Bible, and no help them God. Isn't that the exact same thing as swearing on the Bible except dropping or altering the religious parts? Does that make it idiotic? Should we give up the charade and make everyone swear on the Bible?
So the supposition is that kilns have been found with pots inside, we can demonstrate that the pots have been left undisturbed since the start of their last firing many thousands of years ago so you can judge the orientation of the earth's field at the time of cooling, and, moreover, we know the kilns haven't been moved either?
Color me skeptical.
Note that the article talks about intensity not orientation. Intensity, I understand. Orientation seems implausible with this method.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
I always find it fascinating when modern science and ancient history collide. There have been a number of stories like this over the years as technology advances. It hits me in both my science and technology spot as well as being a fan of ancient history and trying to piece together things from so long ago.
That said when I read it I some how saw some bearded ancient historian crying in the corner as scientists take irreplaceable artifacts of the past, smash them, and grind up the remains for magnetic analysis. I don't *know* how they actually did it, but that's the image in my head.... :)
There's a lot of people in the rest of the world who don't care about anyone named Jesus or Christ, but who have adopted our calendar because it's in very widespread use (the network effect).
Besides, if Jesus existed, he was born a few (we don't know how many) years BC, which makes no sense. We know when the commonly used calendar started We just go with it.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Doesn't change the fact that everyone says AC and BC. ... but perhaps you are one of the few non 'english historians' who uses out of political correctness or SJW syndrome 'CE'. /. ... rofl.
I really doubt you (yes, you as a person) say in real life CE
On the other hand I got already flamed for using the term BC on
Regarding your argument about Christus, well, I would really wonder if he has not lived. But using his 'narrowed' down time of birth for a new calendar and then calling it 'common era' ... erm, I really wonder what the bigger insult is to non Christians. The fact that you use his birth as starting date or that you call that date 'common'?
Most countries that have a different calendar btw. have no problem using their own and the 'internet calender' and probably a thrd one as in reign of the King or Emporer simultaniously.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Before then, the kiln was built around the charge of forms using basically the same clay as the forms, the fire started in the integrated hearth (chimney also integrated to draw the fire), and the charge fired up over several days before the fire was put out and the kiln allowed to cool to the point it could be torn down to unload. Posh kilns with a lot of clay supply might make a hearth and kiln floor of fire brick for re-use, but generally it was as efficient a system as building a space ship then throwing it into the ocean after using it once.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Hanging a dating system off on specific person's birth date has certain problems for historical work, in particular, some historical facts are needed about this person (call him Cleese, and we can all perform the Parrot Sketch before shuffling off) - such as the day of year that Cleese was born on (not in any of the manuals - indications of winter, maybe around the winter solstice?) ; also the year would be a good idea (from 1952 to 1957 BP, as defined above, even according to people who accept the next point) ; and finally, it would be a good idea to be confident that this Cleese person actually existed.
To get around these multiple problems of historical detail, the Common Era is set up to align with the astronomical measures with 0 CE being 4713 years after the last time that the Solar, Metonic and indiction cycles of eclipses and the Moon combined. Simple.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
This is flat out untrue. It could only be true if you spoke to no-one in your "real life" experience who had any background or interest in one of the historical sciences. It's possible that you have such a benighted existence, but I hope you have a more varied life than you imply.
I do say CE / BCE in real life. Whenever we're talking about historical matters at the pub - e.g. with the digger-driver with his collection of locally found stone tools. Or when talking about the several Neolithic to possibly Iron Age burial structures in the area.
Why would you not use the correct terminology? The one thing we can be sure about is that the arrow-knappers and burial-makers were not Cleesian due to this being centuries to millennia before the claimed life of Cleese
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
I would suggest to simply read stuff about historical events ..
Everyone is saying BC if it is before 0 and AC if it is after, in rarer cases AD.
It is only americans and hyper critical /. readers that use CE and BCE.
I'm 50 and had english in schools. This CE and BCE stuff occured in my life a few years ago. Before that everyone understood what BC is ...
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Erm, what point do you want to make?
Again: except for history freaks! no one is using those terms. And then again: it is only americans, probably on a 'social justice political correctness' trip.
Just read wikipedia about random events in history, people as in actual people say BC and AC (not AD as most people are not christians or simply don't remember that english/americsns prefer AD over AC)
In other words: it might be correct english to say BCE, but 90% of the english speakers on the planet don't speak 'correct english'. They use their own words. I'm german, e.g. And no one says in german 'before common aera' so every german will simply say 'before christ' as that is how it is called in german, or italian, or spanish or chinese.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.