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Carbon Dating Gets an Update

samzenpus posted about a year and a half ago | from the looking-back dept.

Earth 137

ananyo writes "Climate records from a Japanese lake are set to improve the accuracy of carbon dating, which could help to shed light on archaeological mysteries such as why Neanderthals became extinct. Carbon dating is used to work out the age of organic material. But the technique assumes that the amount of carbon-14 in the atmosphere was constant — any variation would speed up or slow down the clock. Since the 1960s, scientists have started accounting for the variations by calibrating the clock against the known ages of tree rings. The problem is that tree rings provide a direct record that only goes as far back as about 14,000 years. Now, using sediment from bed of Lake Suigetsu, west of Tokyo, researchers have pushed the calibration limit back much further. Two distinct sediment layers have formed in the lake every summer and winter over tens of thousands of years. The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years. The re-calibrated clock could help to narrow the window of key events in human history. Take the extinction of Neanderthals, which occurred in western Europe less than 30,000 years ago. Archaeologists disagree over the effects changing climate and competition from recently arriving humans had on the Neanderthals' demise. The more accurate carbon clock should yield better dates for any overlap of humans and Neanderthals, as well as for determining how climate changes influenced the extinction of Neanderthals."

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137 comments

nb4 the amateur trolls (5, Funny)

Black Parrot (19622) | about a year and a half ago | (#41701869)

The problem is that tree rings provide a direct record that only goes as far back as about 14,000 years.

What's the problem? That's 7,984 years before the beginning of time.

trolls get fiddy cent (5, Funny)

FatLittleMonkey (1341387) | about a year and a half ago | (#41701977)

Aren't you curious what God was up to before genesis? I mean, if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time? Off making other universes? Were they successful or not? How much baggage does God have? Are the angels the result of those previous geneses? If not, when were the angels created? And the cherubs, oh why won't anyone think of the cherubs?!

The theological implications of this new science are infinite and staggering.

Re:trolls get fiddy cent (3, Funny)

macbeth66 (204889) | about a year and a half ago | (#41702109)

Aren't you curious what God was up to before genesis? I mean, if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time?

Watching pr0n.

Yes, it is a time paradox, but this is God we're talking about.

Re:trolls get fiddy cent (0)

Anonymous Coward | about a year and a half ago | (#41702299)

Maybe the "big bang" was him getting off to the best orgasm in the universe and BAM! here we are!

Re:trolls get fiddy cent (0)

Anonymous Coward | about a year ago | (#41703677)

That sir is sacrilege and in poor taste! I was thinking the same thing.

Re:trolls get fiddy cent (1)

Anonymous Coward | about a year and a half ago | (#41702341)

Watching pr0n. Yes, it is a time paradox, but this is God we're talking about.

No paradox. God is a lot like a Trafalmadorian, able to perceive all time at once. So if you can perceive all of time you can see future pr0n. No subscription necessary. (Best. Superpower. Ever.)

Only, for some reason, that superpower does come with a blind spot or two. For instance, you won't see that the two hairless apes you make are going to defy you and eat your magic apples* in search of knowledge. It's OK though... you make the rules, and can hold them responsible until you get around to sending your fatherless wizard child to be murdered. Spilling wizard blood fixes illegal apple eating. Them's just the mechanics of the universe, and you can find the (abridged) manual on Amazon.com.

Now at this point you might say, "Wait! I have a question." But if you're willing to let that go and eat the occasional cracker, it'll all work out in the end. Super-mega-promise.

See you on the other side! o_O

* Or about 10 other fruits, depending on which edition of the manual you've purchased.

Re:trolls get fiddy cent (0)

Anonymous Coward | about a year ago | (#41703467)

Maybe we're just God's porn machines.

Re:trolls get fiddy cent (0)

Anonymous Coward | about a year ago | (#41703389)

Aren't you curious what God was up to before genesis? I mean, if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time? Off making other universes?

Watching pr0n.

So that's what the kids are calling it these days, "Off Making Other Universes".

Re:trolls get fiddy cent (4, Funny)

IHateEverybody (75727) | about a year and a half ago | (#41702203)

As the documentary Battlestar Galactica explains, all this has happened before and all this shall happen again. God has created many worlds inhabited by humans but each time humans have created artificial intelligence which wiped them out. Often the AIs would continue and advance so far that they would believe themselves human and create their own AIs who would wipe them out as well. And so on and so on....Basically, God is a grad student running a giant experiment and he still hasn't gotten the bugs worked out just yet....

Re:trolls get fiddy cent (5, Funny)

Alsee (515537) | about a year ago | (#41703599)

God is a grad student

That's the problem right there. God has been indoctrinated in radical liberal ideology by college professors.
That's why we need strong conservative Christian leaders in power, to combat God's liberal bias.

-

Re:trolls get fiddy cent (1)

funwithBSD (245349) | about a year ago | (#41705069)

'Abort, Retry, Fail?' was the phrase some wormdog scrawled next to the door of the Edit Universe project room. And when the new dataspinners started working, fabricating their worlds on the huge organic comp systems, we'd remind them: if you see this message, {always} choose 'Retry.' - CID Myers Alpha Centari

Re:trolls get fiddy cent (1, Funny)

girlintraining (1395911) | about a year ago | (#41702613)

Aren't you curious what God was up to before genesis?

The same thing every man does first thing in the morning -- masturbating.

I mean, if God has existed forever, and the universe is just 6000 years old, then what the hell was he doing all the rest of that time? Off making other universes? Were they successful or not?

No. Once he saw what a mess he'd made of things, he put it all in the closet, got drunk, played X-Box, and forgot about the whole thing.

How much baggage does God have?

Let's just say him and the family attend regular therapy sessions...

Are the angels the result of those previous geneses? If not, when were the angels created? And the cherubs, oh why won't anyone think of the cherubs?!

No, the angels were "Version 1.0". After he realized he'd left off a few important bits, like genitals, he created man. It was a big improvement, but still far too buggy, so then he put out service pack 1, codename: Woman. Woman fixed all the major bugs of Man, but unfortunately the network stack had to be upgraded and that's why Man and Woman don't interface well. As to the cherubs... well... They're sortof the BeOS of His world: It was a great idea for the time, but it's since become rather dated, and few people remember them...

Re:trolls get fiddy cent (0)

Anonymous Coward | about a year ago | (#41702679)

So Neanderthals are what?

OS/2 Warp?

Re:trolls get fiddy cent (0)

Anonymous Coward | about a year ago | (#41704009)

So Neanderthals are what?

They never existed.
But what of the bones, you might ask. Good question. Don't question God.

Re:trolls get fiddy cent (1)

invid (163714) | about a year ago | (#41704227)

I'm an atheist but I'll answer that for you just to be the devil's (or God's) advocate. God created time 6000 years ago. God and heaven transcend all things material, including time.

Re:nb4 the amateur trolls (1)

Empiric (675968) | about a year and a half ago | (#41702007)

And its almost as far back as when the first variant of this joke was told on Slashdot.

Re:nb4 the amateur trolls (4, Funny)

girlintraining (1395911) | about a year and a half ago | (#41702025)

What's the problem? That's 7,984 years before the beginning of time.

*Steps out of the TARDIS* Hey, sorry to just pop in like this. Hello internet! Hello slashdot! So, anyway... where was I? Oh yes! Time! So, that idea's been out of style for, what, 500 years... so we were thinking, you must not be from around here, and so we've come to take you back to the 1400s. Don't give me that look! It's for your own good you know. Now, come along... we can't have people all out of time and space, it makes a real mess of the timestream. And these people, these beautiful beautiful people, they're about to do so much, yes, so very very much. And they don't need someone like you setting them back 600 years. Not now. So come on then, in you go!

Re:nb4 the amateur trolls (1)

GNious (953874) | about a year and a half ago | (#41702195)

well played, sir, well played!

Re:nb4 the amateur trolls (0)

Anonymous Coward | about a year ago | (#41704311)

From the username, I suspect that girlintraining might object to your use of "sir".

Re:nb4 the amateur trolls (0)

Anonymous Coward | about a year ago | (#41702721)

How far back do you think he faked the data the whole age of the universe or do you recon he cheats and adds more in as we get more understanding?

Re:nb4 the amateur trolls (0)

Anonymous Coward | about a year ago | (#41703713)

No no no. Satan is the big deceiver and has planted all the so called evidence to lead us into sin. Blissful ignorance is the key to heaven.

C-14 Clock (-1)

Anonymous Coward | about a year ago | (#41703745)

No the exact numbers for C-14 vary as the report says by atmospheric and by solar variables. The reasons are actually lightning and the northern and southern lights events cause the creation of C-14. (It was assumed to be cosmic rays for a long time) As a result C-14 varies very much locally. I have seen data from the Library of Congress through the Congressional Research Service that C-14 data varied by location up to 20% in any given year and tended to be cyclic with the solar activity events. This means that in order to accurately determine C-14 data you have to know the data from that location for all years leading up to the time you are matching to. A 20% variation in C-14 represents a cyclic inaccuracy rendering it very nearly useless for C-14 dating after about 5500 years. The use of Egyptian or Italian data is probably a bit more stable than in the Eastern USA for example. Because of the rare condition of thunderstorms in Egypt or southern Italy this variation is probably much less. None the less due to the global intrusion of the variations and other effects is is really quite useless to determine dates past about 5500 years. It would qualify as speculation.

Other atomic dating methodologies are equally subject to variations. Aging of K-Ar for example assumes a sequested sample with no background variation and that is just impossible to get. The migration of Carbon Isotopes in coal veins discovered in Alabama studies of CO2 sequestration efforts (Clean Coal?) indicated that carbon as migratory Hydrocarbon such as CH4 etc, actually deposited in the coal and the Carbon in the coal prior migrated upwards over time so this was stair step in fashion. This means that even in "solid" or "crystal" sequestration that the concept of atoms not migrating through and that a sample was isolated or sequestered was a farce. As such none of the atomic dating methods beyond about 10,000 years or so is even remotely valid. Even a lunar sample would not be a valid sample because of background radiation variations as well as unknown atomic migration in the samples and similar processes. All C-14 samples are by definition not sequestered!

It is about time we get back to science and quit relying on fanciful tales and "facts" generated out of belief. Data is data but it always depends on the assumptions about the data for accuracy. If those assumptions are accurate then the data is presumed to be accurate in what information it delivers. I know a lot of people will be hurt to learn that they believe things rather than know them but this is just what is reality. I sincerely doubt that they will be persuaded but for those with their eyes open, maybe a few will pick up on this. We have recently seen that the Heisenburg Uncertainty Principal assumptions were wrong. That was gospel for a while in the atomic studies. How much more will fall when we challenge the assumptions and "Facts" to see reality remains to be seen.

Speaking of "get back to science"... (1)

Dr. Manhattan (29720) | about a year ago | (#41704135)

Aging of K-Ar for example assumes a sequested sample with no background variation and that is just impossible to get. The migration of Carbon Isotopes

Two problems.

  • 1. You dispute K-Ar but talk exclusively about carbon migration.
  • 2. You do not appear to know what an isochron [talkorigins.org] is.

All of which is ultimately meaningless (-1, Flamebait)

Gothmolly (148874) | about a year and a half ago | (#41701879)

To anyone who works for a living.

Re:All of which is ultimately meaningless (0)

Anonymous Coward | about a year and a half ago | (#41702159)

Which doesn't include you, obviously.

Neanderthals aren't extinct... (4, Funny)

sitarlo (792966) | about a year and a half ago | (#41701883)

...they dominate U.S. politics!

Re:Neanderthals aren't extinct... (3, Insightful)

Black Parrot (19622) | about a year and a half ago | (#41702079)

...they dominate U.S. politics!

Probably because they also dominate the voting booths.

Re:Neanderthals aren't extinct... (0)

Anonymous Coward | about a year ago | (#41702755)

Not so surprising as during their last Great Diaspora, they all relocated to the US.

Re:Neanderthals aren't extinct... (1)

morgauxo (974071) | about a year ago | (#41704693)

I want to move my previous comment to here please! "I doubt it. They (neanderthals) had bigger brains than Homo Sapiens Sapiens." Maybe offspring of Homo Floresiensis managed to escape their island and grew taller...

Re:Neanderthals aren't extinct... (0)

Anonymous Coward | about a year ago | (#41703475)

True. I've run into quite a few Neanderthals during my lifetime.

Lucky Japanese (0)

Anonymous Coward | about a year and a half ago | (#41701891)

In another 10,000 years they will be able to find at least two more radioactive sediment layers to refine their calculations.

All Fooy (-1)

Anonymous Coward | about a year and a half ago | (#41701933)

The half life of carbon-14 is only about 5000 years. So either other, unstable isotopes have been degrading into carbon-14:
in which case you should have science to back up those rates of isotopic altercations- or your science is bunkum.

Re:All Fooy (4, Informative)

nedlohs (1335013) | about a year and a half ago | (#41701981)

Maybe if you knew what a half life was you wouldn't find it so confusing?

Re:All Fooy (5, Informative)

Eunuchswear (210685) | about a year and a half ago | (#41702247)

Maybe if you knew what a half life was you wouldn't find it so confusing?

His comment doesn't show that he doesn't understand the concept of a half life.

I'ts a superficialy reasonable question - if we know that C14 is decaying then it must of come from somewhere.

But his error is to assume the only place it could have come from is the decay of something else.

In fact it's generated by cosmic rays hitting Nitrogen, a beta particle (electron) is captured by N14 giving C14.

Re:All Fooy (2)

Stirling Newberry (848268) | about a year ago | (#41703459)

Not correct, absorbing an electron would not change the atomic number. N14 absorbs a thermal neutron, and C14 decays by beta decay. K capture emits a neutrino.

Re:All Fooy (0)

Anonymous Coward | about a year ago | (#41704983)

Not correct, absorbing an electron would not change the atomic number. N14 absorbs a thermal neutron, and C14 decays by beta decay. K capture emits a neutrino.

If N14 absorbed a neutron, it would become N15. Beta capture means one of the protons in the N14 becomes a neutron, reducing the atomic number by 1 and making C14.

Re:All Fooy (2)

Stirling Newberry (848268) | about a year ago | (#41703503)

Since the decay of fission products produces thermal neutrons, some of these can be absorbed by the very common N14 to become C14. Above ground atomic tests produced a spike of C14, for example.

Here's the information. (5, Informative)

mosb1000 (710161) | about a year ago | (#41703483)

Usually when I see a post moderated as informative, it leads me to believe it may contain information of some kind. I think this would be better characterized as insightful.

If anyone does't understand what the parent is talking about, the half-life [wikipedia.org] of Carbon 14 is 5,730±40 years [wikipedia.org]. That means that 52,000 years is a little more than 9 half-lives. By taking 1/2 and raising it to the power of 9, we can conclude that about 0.2% of the original carbon 14 will remain in the oldest layers of sediment.

As for the question of where the Carbon 14 is coming from [wikipedia.org], we know that it's formed by cosmic radiation striking the atmosphere, and that the amount in the atmosphere varies slightly from year to year. As this article has explained, the purpose of this research is to get a better idea of how much Carbon 14 was in the atmosphere every year so that we can get a better idea of how old a piece organic matter might be based on it's isotopic ratio (the fraction of the carbon that is Carbon 14).

Re:All Fooy (1)

Black Parrot (19622) | about a year and a half ago | (#41702091)

The half life of carbon-14 is only about 5000 years. So either other, unstable isotopes have been degrading into carbon-14:
in which case you should have science to back up those rates of isotopic altercations- or your science is bunkum.

You must be thinking about carbon-5. Carbon-14 is guaranteed for 14,000 years.

Re:All Fooy (0)

Anonymous Coward | about a year and a half ago | (#41702097)

The half life of carbon-14 is only about 5000 years. So either other, unstable isotopes have been degrading into carbon-14:
in which case you should have science to back up those rates of isotopic altercations- or your science is bunkum.

You must be thinking about carbon-5. Carbon-14 is guaranteed for 14,000 years.

http://en.wikipedia.org/wiki/Carbon-14
I think you need to read wikipedia again.

Re:All Fooy (0)

Anonymous Coward | about a year and a half ago | (#41702167)

I think you need to look at the comment that was replying to again. It is either such a profoundly wrong understanding of half-life, or extremely poorly stated, and many probably don't think that warrants a serious reply... not that making a good comment stops people from making jokes either. Nonetheless, giving the benefit of the doubt and guessing the original poster doesn't understand how there can be C14 when most of it should have decayed away and stayed away without a source, the Wikipedia article right at the beginning describes the source and this story here on Slashdot is exactly about the science that backs up those rates.

Re:All Fooy (0)

Anonymous Coward | about a year ago | (#41703201)

Whooooooosh!!!!!

Re:All Fooy (1)

Anonymous Coward | about a year ago | (#41703623)

Yes, the half-life of carbon-14 is only about 5000 years. After 5000 years that means half the original C-14 remains. After 10000 years, 1/4 the original C-14 remains. After 15000 years, 1/8th. After 20000 years, 1/16th. After 25000 years, 1/32nd. After 30000 years, 1/64th, and so on. Typically, with radiometric dating techniques you can keep on measuring the parent (radioactive/decaying) isotope to daughter (product) isotope until about 10 half-lives have gone by. After that, so little of the original parent radioactive isotope is left, and it is so easy to contaminate the sample with a wiff of modern material, it is tricky to go any further. If you use a really large sample and particularly precise techniques, sometimes you can stretch that a little. For C-14 dating that means the nominal range is about 50000 years. You can stretch a little beyond that if you are careful (I think the max is ~100000 years).

Because the Earth is very old, it's logical to wonder why all C-14 isn't decayed by now. The simple answer to that is: it is being constantly created by cosmic rays penetrating into the atmosphere and generating C-14 from N-14. It is an equilibrium process of generating C-14 and then letting it decay. More importantly, the rate of its generation does vary a bit, and that's what this study (and a lot of other previous studies) have been calibrating. The difference between using the modern-day atmospheric C-14 concentration (technically, the amount of C-14 in the atmosphere before we screwed it up with nuclear weapon testing) and the recalibrated values is about 10-20%, due to the variation in C-14 concentration in the atmosphere over the last 50k years or so.

So, I'm not quite sure what your problem with C-14 dating is, but I think you need to re-evaluate some of the basics of the method. I recommend the wikipedia page [wikipedia.org] as a start.

Why would /. care about update to the dating site? (1)

Anonymous Coward | about a year and a half ago | (#41701939)

:]

Lucky grad student (4, Interesting)

tsotha (720379) | about a year and a half ago | (#41701945)

The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

Re:Lucky grad student (2)

nedlohs (1335013) | about a year and a half ago | (#41701959)

104,000 according to "two distinct sediment layers have formed in the lake every summer and winter ".

Re:Lucky grad student (0)

Anonymous Coward | about a year ago | (#41703587)

You don't really need to count both the summer and winter stripes. If you count the number of winters, you pretty much know there have been just as many summers.

Unless one of the winter stripes is really thick.

Re:Lucky grad student (1)

jersacct (1261566) | about a year and a half ago | (#41701973)

Two distinct sediment layers have formed in the lake every summer and winter over tens of thousands of years.

Actually, it's 104,000.

Re:Lucky grad student (5, Insightful)

Black Parrot (19622) | about a year and a half ago | (#41702039)

The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

No problem, at 80 hours a week [slashdot.org] a grad student should be able to finish well before his indentured servitude expires.

Re:Lucky grad student (4, Informative)

Anonymous Coward | about a year and a half ago | (#41702149)

Usually it's not just "count". Every layer must be checked to see if there are no bioturbations or other disturbances, that could hint a missing layer. Also layer thickness is measured in order to create deposition speed time model, to allow to correlate particular log with other borehole (varve) logs.
http://en.wikipedia.org/wiki/Varve [wikipedia.org]
http://en.wikipedia.org/wiki/Rhythmite [wikipedia.org]

Of course, I haven't RTFA, as I'm located in a "leading science university" (rectors quote) and I don't have an access to Science.

Re:Lucky grad student (1)

Eunuchswear (210685) | about a year and a half ago | (#41702265)

The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

Now imagine how the CRU guys felt about getting hundreds of copy/pasted FOI requests for their painstaking work.

Re:Lucky grad student (2)

DerekLyons (302214) | about a year ago | (#41704117)

The researchers collected roughly 70-meter core samples from the lake and painstakingly counted the layers to come up with a direct record stretching back 52,000 years.

Holy crap. "Painstakingly" doesn't even begin to cover counting 52,000 stripes in a core sample.

Yep. And it's also one of the reasons the US's current fad for STEM in education will fail miserably. Real science is hard, boring, time consuming, and painstaking - it's not edutainment and it's not something that can be wrapped up in time for a commercial break. The real problem in the US isn't educational fads, it's lack of attention span.

It is not very accurate, to begin with!! (0, Insightful)

Anonymous Coward | about a year and a half ago | (#41701987)

Carbon dating to me seems to be used to further scientific data, in order to achieve the results they want. Captain Obvious says it is very inaccurate, and no matter what they have done or try, to advance Carbon dating techniques it already as that stigma of doubt because it is impossible to get within a few hundred years, let alone decades. Not saying that another technique cannot be used or something new won't come along but I do not buying into the Carbon Dating reports..

I not against Carbon dating or the results, but I om not going to bet my life on it either.

Re:It is not very accurate, to begin with!! (1)

EmperorOfCanada (1332175) | about a year and a half ago | (#41702019)

It may not be perfect but Carbon Dating makes the blurry less blurry and this latest development sharpens it further.

Re:It is not very accurate, to begin with!! (0)

Anonymous Coward | about a year ago | (#41702927)

lol it sharpens it for what, less than 1% of Earth's history? That's why ages of things always bother me. We have no idea how much carbon14 was around in the past. By assuming anything its just pseudo science. But if we tell the truth then anyone claiming another truth wins so we have to lie.

Re:It is not very accurate, to begin with!! (0)

Anonymous Coward | about a year ago | (#41703923)

Not just 1%. Carbon dating is valid for determining age within a range, somewhat depending on the amount of sample material. As the amount of C-14 decreases, uncertainty increases.. However! If there's no C-14 at all, i.e. it has all decayed away, you can tell that it must be very old indeed.

But most importantly, carbon dating is just another tool in the toolbox. If you're not using other tools as well, you're not doing your job properly.

Re:It is not very accurate, to begin with!! (1)

kanweg (771128) | about a year ago | (#41704125)

"We have no idea how much carbon14 was around in the past. By assuming anything its just pseudo science. But if we tell the truth then anyone claiming another truth wins so we have to lie."

ACs (C=xtian/Coward? Oh well) are not likely to educate themselves. Should you want to do a Truth or Dare: Do google where C14 comes from. You'll be surprised.

(And don't you really understand counting? Tree ring counting? Varves counting. If you fell a tree, you can count the rings? You can do a C14 determination for each ring? You can use other (older) trees with overlapping age ranges and hence overlapping ring patterns to continue getting values for older ages? You can go on doing that? You can do the same for varies, which is what the Japanese did. And being scientists, they cross-reference such values for various sources. And when you do that real science, all your post is reduced to BS.

Bert
"By assuming anything its just pseudo science."
But assuming your holy book is correct, doesn't make it a pseudo religion, does it? Nope, it is the one true religion. All the other thousands of gods have been made up, but yours is real. Yup.

Re:It is not very accurate, to begin with!! (1)

Anonymous Coward | about a year ago | (#41704831)

We have no idea how much carbon14 was around in the past.

If only there were studies that test how much carbon-14 were around and compare the results to other dating methods. And if only such studies would get posted to Slashdot. And if only such studies went back to the 60s, so that the articles, that would be posted to Slashdot if they had existed, could mention some historical context for how long such work has been going on.

lol it sharpens it for what, less than 1% of Earth's history?

Good point, I guess it is useless then, as no one cares about what happened in that one percent of Earth's history. We should stop researching historical writings too, as those cover even less of Earth's history.

Re:It is not very accurate, to begin with!! (0)

Anonymous Coward | about a year and a half ago | (#41702145)

Astronomy to me seems to be used to further scientific data, in order to achieve the results they want. Captain Obvious says our knowledge of distances between the planets is very inaccurate, and no matter what they have done or try, to advance measurement techniques it already as that stigma of doubt because it is impossible to get within a few million km, let alone metres. Not saying that another technique cannot be used or something new won't come along but I do not buying into the reports of Jupiter having moons....

Yours sincerely,

1609

Re:It is not very accurate, to begin with!! (1)

pod (1103) | about a year ago | (#41702965)

Jupiter having moons has nothing to do with distances.

Re:It is not very accurate, to begin with!! (2)

Riddler Sensei (979333) | about a year and a half ago | (#41702175)

Carbon dating to me seems to be used to further scientific data, in order to achieve the results they want.

I'm not sure what you're trying to imply here. What "they want" is the most accurate answer our CURRENT tools can provide. And as the margin of error of the tools gets reduced over time, they measure again. Trying to narrow down our accuracy doesn't exactly scream "hidden agenda" to me.

...because it is impossible to get within a few hundred years, let alone decades.

Christ! I can appreciate the desire to really dial in our techniques, but expecting that after only about a half a century of refining these techniques that we know the difference between 10,643 and 10,633? We're impressive creatures but it sounds like you're holding out for Doctor Who to swing by and show you history.

Really, it's the best tool we've currently got, and you don't throw out the best tool you've currently got in favor of eyeballing it. Looking at the current margin of error and throwing carbon dating out is throwing the baby out with the bath water.

Re:It is not very accurate, to begin with!! (1)

wonkey_monkey (2592601) | about a year ago | (#41702705)

This is Slashdot, where the uninformed gather to demonstrate their superiority by scoffing at every scientific advance. The ones they don't understand they just dismiss as impossible.

Re:It is not very accurate, to begin with!! (0)

Anonymous Coward | about a year and a half ago | (#41702177)

Oh well, there is a "stigma of doubt," so we shouldn't bother trying to improve it. If the gut feeling of the masses disagree, don't bother actually looking at data or trying to improve the method and its verification via other measurements... it has already been disproven in the court of public opinion...

Re:It is not very accurate, to begin with!! (1)

mosb1000 (710161) | about a year ago | (#41703595)

it is impossible to get within a few hundred years, let alone decades

If you're looking at things that happened more than 10,000 years ago, getting it within a few hundred years is all the accuracy you need. But just thinking about how isotopic ratios are measured, you can see that it would give the most precise measurements near the half life of Carbon 14 (5,730 years) with accuracy increasing from the time the plant or animal died up to 5,730 years and decreasing thereafter. The actual accuracy would also vary by the size and purity of the sample as well as the sensitivity of the instrument used, so you can't really speak in general terms about the accuracy of carbon dating.

I've tried ALL of the CARBON DATING services... (-1)

Anonymous Coward | about a year and a half ago | (#41702107)

Spoiler alert: All the girl profiles are FAKE!!!

I don't get it ... (4, Interesting)

sgunhouse (1050564) | about a year and a half ago | (#41702119)

Wouldn't the amount of C-14 have been the same for humans and Neanderthals at any given time? Therefore while we may be unclear exactly when they went extinct (presuming Bigfoot is not a surviving branch of Neanderthals), we should have a pretty good idea in the overlap. Unless they use different dating methods for different events, this really shouldn't change the general picture.

Re:I don't get it ... (3, Insightful)

dadelbunts (1727498) | about a year and a half ago | (#41702243)

I think the point of this article is that before this, they could only really look back 14,000. Since Neanderthals went extinct 30,000 years ago, that doesnt help much. Now they can look back 52,000 years. I know no one reads the article, but at least read the summary. Its all right there. I figured it out and im drunk.

Re:I don't get it ... (1)

riverat1 (1048260) | about a year and a half ago | (#41702491)

I think the point of this article is that before this, they could only really look back 14,000.

No, carbon 14 dating is good for around 60,000 years before its level gets to low for accuracy. They could measure that all along. This research merely extends the accuracy that tree rings provided back to 52,000 years thus narrowing the range of years found for a specimen.

Re:I don't get it ... (4, Informative)

sFurbo (1361249) | about a year and a half ago | (#41702513)

No, they could go back further, up to 55,000 years, I think, by assuming that the C-14/C-12 ratio has always been the same. This is not quite the case, as the levels of cosmic radiation changes, so the production rate of C-14 changes. If we have an object that is known to have a certain age, we don't need to guess, we can compare directly. However, really old objects with known dates are hard to come by. You more or less need an annual cycle going up to today, so that you have an anchored chronology. Previously, tree ring data was the best anchored chronology that could be carbon dated (I assume there is too little C in glacial ice, I don't know why corals can't be used. Perhaps sea water might not always be in C equilibrium with the atmosphere?), so we could only go back 14,000 years. Now, we have an carbon-dated anchored chronology going back 52,000 years, so carbon dating gets much more accurate.

Re:I don't get it ... (1)

Stirling Newberry (848268) | about a year ago | (#41703523)

Since most C14 is generated in the upper atmosphere, there is no telling when the Carbon in sea water was absorbed, meaning there's no base line.

Re:I don't get it ... (1)

phantomfive (622387) | about a year and a half ago | (#41702297)

presuming Bigfoot is not a surviving branch of Neanderthals

That's such a pretty idea lol

Re:I don't get it ... (0)

Anonymous Coward | about a year ago | (#41705079)

presuming Bigfoot is not a surviving branch of Neanderthals

That's such a pretty idea lol

I am a politically connected Neo Anderthal you insensitive clod.

Re:I don't get it ... (1)

sFurbo (1361249) | about a year and a half ago | (#41702469)

Climate changes is also a possibility, which AFAIK, is dated from ice cores.

What affect did the glaciers have? (3, Insightful)

erice (13380) | about a year and a half ago | (#41702133)

I'm amazed that they found a clear seasonal pattern in a lake going back 52,000 years. Lakes are short lived structures, geologically speaking and 52,000 years is quite far into the last ice age. I guess the lake somehow managed to avoid being glaciated and managed to avoid being washed away by the melt waters. Impressive! I haven't located an ice age map of Japan so I don't know how much, if any, of Japan was actually covered by ice. It is far enough North but the ice sheet was not uniform. (Parts of Alaska were ice free)

Re:What affect did the glaciers have? (2)

riverat1 (1048260) | about a year and a half ago | (#41702525)

I looked up the Würm glaciation on Google and found this map. [factsanddetails.com] Being west of Tokyo there wasn't a lot of glaciation there.

Uneven all over. (1)

Anonymous Coward | about a year and a half ago | (#41702179)

The problem isn't just that C-14 isn't a constant over time.. It's varies over different parts of the planet. How does there lake account for that?

Re:Uneven all over. (0)

Anonymous Coward | about a year and a half ago | (#41702423)

More samples over more areas of the earth help to "paint a picture" of the variations as well I'd think. The more samples there are, the more accurate it will be.

Re:Uneven all over. (1)

sFurbo (1361249) | about a year ago | (#41702561)

I can't vary that much over different parts of the planet. For one hemisphere, the atmosphere is mixed on at least a monthly basis. Crossing the equator takes a bit longer, bu nevertheless, it is more or less complete after 5 years [wikipedia.org]. There is some problems with sea dwelling creatures, as water might come from the deep sea, and not be in equilibrium with the atmosphere.

Pole reversal. Carbon dating is broken. (-1)

Anonymous Coward | about a year and a half ago | (#41702361)

Cosmic rays interacting with nitrogen create the unstable carbon 14 being measured. Okay.

However, when the Earth's poles reverse, as they do periodically, the magnetosphere collapses and Earth is flooded with cosmic rays throughout the biosphere, increasing the level of destructive nitrogen reactions.

The resulting blips of high C14 concentrations serve to throw off the accuracy of carbon dating measurements. A constant is mistakenly assumed.

Earth is a great deal weirder than is generally understood.

Re:Pole reversal. Carbon dating is broken. (4, Informative)

riverat1 (1048260) | about a year ago | (#41702571)

The last magnetic reversal of the poles was 780,000 years ago, 720,000 years before carbon 14 dating is useful. I doubt it has any effect.

Re:Pole reversal. Carbon dating is broken. (1)

sFurbo (1361249) | about a year ago | (#41702591)

If only we had objects with known dates, this wouldn't be a problem, as you could compare directly. The best would, of course, be some kind of annual layers, so you could count how old they are. Oh, if only there was some [wikipedia.org] method or another [slashdot.org] that worked that way.

Besides, I don't really think an event that last took place 780,000 years ago is going to affect a dating method where only traces too small to be measured exist after 100,000 years.

Re:Pole reversal. Carbon dating is broken. (1)

Anonymous Coward | about a year ago | (#41702963)

Yes, that is why it is so convenient when they find coins with stamped dates like "70 BC" on archeological sites!

Re:Pole reversal. Carbon dating is broken. (1)

kanweg (771128) | about a year ago | (#41704203)

The conversion of Nitrogen to C14 is caused by a neutron http://en.wikipedia.org/wiki/C14_dating [wikipedia.org]. Being not charged, it tends to be rather insensitive to magnetic fields.

Chance that you're religious: above average.

Bert

Re:Pole reversal. Carbon dating is broken. (0)

Anonymous Coward | about a year ago | (#41704973)

Cosmic rays consist of vast majority of charged particles though. The neutrons involved in the production of carbon 14 are pretty much all from charged particles hitting higher in the atmosphere and creating a shower of secondary particles. So a reversal could potentially change carbon-14 levels due to change in cosmic ray fluxes, although the impact of such a short (in terms of geological time) exposure to new C14 might be a rather minor cumulative effect in dating depending on exactly how much change in production it causes.

But the issue is moot, because the last reversal happened about 780ka ago, an order of magnitude longer ago than the time period used for carbon dating.

My sources on the inside say (0)

Rogerborg (306625) | about a year and a half ago | (#41702419)

That carbon dating has always been as accurate as you can afford. You decide the date that you need in order to confirm your thesis, send your sample to as many labs or as many times as your budget allows, then pick the closest answer from the essentially random set of results.

Anyone on the inside of the inside care to confirm or refute that?

Re:My sources on the inside say (0)

Anonymous Coward | about a year and a half ago | (#41702465)

Your source ... do you mean creationists? That's what creationists say all the time.

Re:My sources on the inside say (1)

TheMathemagician (2515102) | about a year ago | (#41702805)

It's not that bad. Carbon14 dating does have a sound scientific basis and is ballpark correct. However there is sufficient variation between labs that it's clear the measuring process itself is not precise and, worse, there are clear systemic differences between C14 dates and dendrochronology. It's not clear what causes this - variation in C14 over time? over different regions? different rates of decay? - so anything which helps reconcile the figures is good.

Re:My sources on the inside say (5, Informative)

Anonymous Coward | about a year ago | (#41703231)

That carbon dating has always been as accurate as you can afford. You decide the date that you need in order to confirm your thesis, send your sample to as many labs or as many times as your budget allows, then pick the closest answer from the essentially random set of results.

Anyone on the inside of the inside care to confirm or refute that?

I'm not on the inside, but I've read some of the papers.
Every few years there is an International Radiocarbon Intercomparison, where a batch of different types of samples are sent to most of the world's labs (~100) to date. The results are then compared. Overall stats are published anonymously, and individual labs can publish their results if they want.
The most accurate method (AMS) shows error rates of ~1%, while older methods give error rates of up to 10%.
Of course there are some classes of samples which present special problems; the study samples are ones which don't present major contamination issues.
The full study from 2003 is open access: here [arizona.edu]

Re:My sources on the inside say (1)

Anonymous Coward | about a year ago | (#41703487)

There are multiple techniques available that can be more or less precise (e.g., regular C-14 dating versus atomic mass spectrometry), and these will inevitably yield slightly different results because of the normal scientific measurement process. But essentially random results and testing until you get the one you want? Uh, no. In fact, one of the clearest demonstrations that the technique is not random is that you can take a series of samples from different layers of sediment, and within the analytical uncertainties of the measurements, they come out in the right chronological order (e.g., deeper samples older than higher samples in the succession of layers). If it were random, no such correlation would be expected to occur.

Only people unreasonably skeptical of the technique, or who have never actually worked with it, would think there aren't other constraints on the results that would test the overall validity. Your "sources on the inside" don't know what they are talking about, or apparently have an axe to grind.

Neanderthals extinction (0)

Anonymous Coward | about a year ago | (#41702655)

Neanderthals extinction reason is very simple they were too yummy.

Old news (2)

bothemeson (1416261) | about a year ago | (#41703085)

The Internationally agreed Radiocarbon calibration curve (IntCal) - co-ordinated from Belfast University - takes info from ice-cores, lake sediment cores, tree-rings, corals, etc from the Southern and Northern hemispheres (there's an offset between them) puts them together (this work is done by statisticians using specially developed methods rather than other scientists using off-the-shelf techniques) and although some scientists would rather that only their work was used (as they can then claim whatever 'accuracy' they wish to claim) independent verification of lab practices is extremely useful in the work. The most recent published work dates back to 50,000 years BP ('before present' where 'present' is 1950) and the next set of curves (IntCal 12) - being worked on at the moment will take it back further. Abstract for IntCal 09 - http://eprints.whiterose.ac.uk/10694/ [whiterose.ac.uk]

Not particularly new? (1)

mrthoughtful (466814) | about a year ago | (#41703647)

Reading one of the articles ( http://researchcommons.waikato.ac.nz/bitstream/handle/10289/3622/Hogg%20Intcal09%20and%20Marine09.pdf [waikato.ac.nz] ) seems to make it clear that the Lake Suigetsu project is a player, but only one of many, in the project to develop a better INTCAL chronology. It may be obvious to some, but any single dataset is not particularly useful until it is corroborated with many others. The Suigetsu project has been at work for several years and, although there has been some revision made to their baseline data, it hardly seems like headline news.

OTOH, it's always great to hear what scientists have been up to, regardless of the field.

Archaelogical Mysteries (-1)

Anonymous Coward | about a year ago | (#41705155)

The only reason these remain 'mysteries' is because the Hand of God intensionally obfuscates history from our knowledge; because, heh, how else could science be wrong?

Oh wait, in this case, scientists discovered that their previous "Can only date things back 14,000 years" idea WAS WRONG.

Science is wrong, constantly. Science is just allowed to constantly update it's views based on the consensus of thousands of priest^H^H^Hscientists around the globe when something proves to be wrong. If only science had these things, like say, some kind of book, which it's detractors could constantly quote out of context, to make specious points about.

Perhaps scientific texts about SPONTANEOUS GENERATION:

Aristotle The History of Animals Book 5, Chapter 1: "So with animals, some spring from parent animals according to their kind, whilst others grow spontaneously and not from kindred stock; and of these instances of spontaneous generation some come from putrefying earth or vegetable matter, as is the case with a number of insects, while others are spontaneously generated in the inside of animals out of the secretions of their several organs."

Hippolytes' History Chapter 12, Verse 7-23: "And it was spake by Saint Anaximander on that day, the day being begat by the sun rotating about the Earth, that aquatic lifeforms spontaneously spring forth into life, and in the adult mature form. Anaximenes questioned him, stating that air was necessary to impart life, how can the fish obtain it? Empedocles agreed saying, "This is the word of Science, thanks be to it!"

Jan Baptist van Helmont, Chapter 4 Verse 9001 "To beget mice, in the fashion that science doth make us do, one must first acquire soiled cloth. This cloth must not be soiled in the common ways of our heathen enemies, nay, it must be soil'd with the proceeds of human defocation and the best of the wheat harvest. And, be leaving this cloth, be 21 days passed, a miracle of birth, mice appeared."

I say all these things, in jest, to remind people to not immediately jump on the "Science is right" bandwagon, which inevitably leads to the fallacious "If science is right, then nothing else may be right, which means religion is wrong:. QED". When persons attempt to inductively prove that religion is wrong because science is right, they fall into the same logical fallacy which the religious extreme-wing fall into when proving 'their' beliefs.

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