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Mysterious radiation burst recorded in tree rings - Comments

Outrider's Avatar Comment 1 by Outrider

Just so I can head off some arguments at the pass - what are the implications of this C14 spike for radiocarbon dating? Presumably negligible, seeing as pretty much everything dated by this method is at least thousands of years older than this...?

Can anyone confirm?

Cheers,

O.

Mon, 04 Jun 2012 15:44:08 UTC | #945492

Jos Gibbons's Avatar Comment 2 by Jos Gibbons

An increase of 1.2 % in the C-14 levels would take 0.017 half-lives = 99 years to cancel through radiometric decay. This means the amount of time for which C-14 was decaying is 99 years longer than the radiometric test implies. For a source dating to AD 775, which is today 1237 years old, this is an 8.0 % error (as a percentage of the real age of 1237 years, rather than the mistaken age of 1138 years, of which it's an 8.7 % error). For comparison, radiometric dating usually has a 1 % error. Luckily, trees this young can be dated to the exact year by dendrochronology anyway.

(If anyone sees an error in here anywhere, point it out.)

Mon, 04 Jun 2012 16:16:48 UTC | #945497

God fearing Atheist's Avatar Comment 3 by God fearing Atheist

I would have thought C14 dating was already calibrated against dendrochronology.

If not, I'll give it another 6 months (after the publication of this paper) before it is.

How do they know the AD 775 blip is 20 times the normal variation if they haven't been calibrating?

Mon, 04 Jun 2012 17:08:25 UTC | #945508

All About Meme's Avatar Comment 4 by All About Meme

Some very energetic event occurred in about AD 775.

Exactly what that event was, however, is more difficult to determine
.

It was Jesus.

Traveling near the speed of light on His way to heaven, our Lord made a slight error in his trajectory calculation, and was forced to blast His way through the Pisces-Cetus Supercluster.

Mon, 04 Jun 2012 17:24:57 UTC | #945515

xsjadolateralus's Avatar Comment 5 by xsjadolateralus

Radiation burst...Energy... Sounds like it will be found to have been the sun (?).

Probably not much of a mystery, more of a miss story.

You would think the wooers would get rather used to this sort of thing. If they only understood the implications of science they would realize how let down they should feel.

Then again, it seems that they float around, waiting for the right wave. A story about mysterious energy, sounds like the right wave. Quick jump on it before it dies! Ride it out until the mystery is solved! Like Wiley coyote, they suspend. Until science discounts the existence of their wave and down they go. Back to floating...waiting for the next wave...

Mon, 04 Jun 2012 19:04:08 UTC | #945530

zengardener's Avatar Comment 6 by zengardener

Cloaked alien space ships were having a high altitude dog fight with proton guns, over Uranium mining rights on Earth.

Didn't even make the front page of the Galactic Examiner.

Mon, 04 Jun 2012 19:29:11 UTC | #945538

rod-the-farmer's Avatar Comment 7 by rod-the-farmer

Nah. Some flying horse in the middle east went to warp drive and there was a radiation spike.

Mon, 04 Jun 2012 19:57:52 UTC | #945550

Metamag's Avatar Comment 8 by Metamag

Comment 6 by zengardener :

Cloaked alien space ships were having a high altitude dog fight with proton guns, over Uranium mining rights on Earth.

Didn't even make the front page of the Galactic Examiner.

Ah, if only universe was that exciting :(

Mon, 04 Jun 2012 20:15:47 UTC | #945558

Alan4discussion's Avatar Comment 9 by Alan4discussion

Comment 6 by zengardener

Cloaked alien space ships were having a high altitude dog fight with proton guns, over Uranium mining rights on Earth.

There are natural proton guns out there, but we would expect gravitational effects to show if they approached or passed the Solar system! - http://imagine.gsfc.nasa.gov/docs/science/know_l1/pulsars.html

Mon, 04 Jun 2012 20:35:42 UTC | #945564

Shrinking_Dogma's Avatar Comment 10 by Shrinking_Dogma

          [Comment 1](/articles/646125-mysterious-radiation-burst-recorded-in-tree-rings/comments?page=1#comment_945492) by  [Outrider](/profiles/112476)          :


                 Just so I can head off some arguments at the pass - what are the implications of this C14 spike for radiocarbon dating? Presumably negligible, seeing as pretty much everything dated by this method is at least thousands of years older than this...?Can anyone confirm?Cheers,O.

Actually it begins to get less used many thousands of years older than this mainly because of calibration issues. I guess the most accurate measurements would be about 1 half life down (about 6000 years ago).

          [Comment 3](/articles/646125-mysterious-radiation-burst-recorded-in-tree-rings/comments?page=1#comment_945508) by  [God fearing Atheist](/profiles/50368)          :


                 I would have thought C14 dating was already calibrated against dendrochronology.If not, I'll give it another 6 months (after the publication of this paper) before it is.How do they know the AD 775 blip is 20 times the normal variation if they haven't been calibrating?

It is all pretty well calibrated (ie wood from a precise year's dendro date is tested to see how much C14 it has and compared with how much it should have if radiation was constant) although there is some local variation in C14 levels and also in availability of calibrated known-date samples. This result should make very little difference in that regard.

Interesting when you measure C14 to start with to work out a date you compare levels to a notional 1950 benchmark. Why 1950? well if you check C14 levels in nature they are almost flat until 19th century (the described blip excepted!) and then suddenly there is a rapid and growing decrease in C14 - fossil fuels releasing C14less CO2 into the environment. Then come the 50s a massive C14 spike...nuclear testing.

If you see the graph and compare it to the thousands of years pre-industrial levels one could have no doubt of the dramatic and measureable impact that, unseen, humans have had on the environment.

Mon, 04 Jun 2012 23:42:59 UTC | #945604

ridelo's Avatar Comment 11 by ridelo

Comments 4, 6, 7, 8, 9... Boys will stay boys...

Tue, 05 Jun 2012 08:30:06 UTC | #945655

zengardener's Avatar Comment 12 by zengardener

Comment 11 by ridelo Comments 4, 6, 7, 8, 9... Boys will stay boys...

Yes, even with our frosty beards.

Sat, 09 Jun 2012 02:51:56 UTC | #946490

bluebird's Avatar Comment 13 by bluebird

This was also in NG news ~ link text

The team tested cedar trees from southern Japan. Giant sequoias and bristlecone pines are hoped to reveal info, too.

Sat, 09 Jun 2012 19:25:44 UTC | #946610