0:04

Welcome to tech Stuff, a production

0:06

from my Heart Radio. Hey

0:12

there, and welcome to tex Stuff. I'm your

0:14

host, Jonathan Strickland. I'm an executive producer

0:16

with I Heart Radio, and I love all things

0:19

tech and typically I

0:21

would have a news episode for you

0:24

on today, which is Thursday,

0:26

April twenty one,

0:28

but this week got away

0:30

from the big time. On the bright

0:33

side, we have a really

0:35

cool thing coming up early

0:37

next month that um

0:40

tech Stuff is taking part in that I think

0:42

you guys are really gonna dig. But

0:45

that doesn't help me today, does

0:47

it. So instead of a news episode,

0:50

we're going to have a little bit

0:52

of a classic episode here. I thought,

0:55

because I'm feeling so very old as

0:57

I try to to make sure

0:59

I have these episodes ready for you guys,

1:02

it would be good to kind of take stock.

1:04

And by that I mean we're going to listen to a

1:06

classic episode called is carbon

1:09

Dating on the Way Out? This

1:12

episode originally published on August

1:15

two thousand and fifteen. I

1:17

hope you enjoy. This

1:20

comes from nikkil Cardale, and

1:22

I do apologize that I'm

1:24

sure I mispronounced your name. The

1:27

request was, could you do an episode explaining

1:29

this carbon dating is pretty useful,

1:31

So this effect seems relevant and

1:35

uh Cardale actually uh

1:38

commented on and and included another

1:40

tweet from real scientists that

1:42

included an article titled will our fossil

1:45

use ruin our ability to use carbon

1:47

dating as a scientific tool? This

1:50

is really fascinating the idea of using

1:52

carbon dating, uh, and how

1:55

that that method might be

1:58

in jeopardy because the

2:00

use of fossil fuels. So I

2:02

thought I would go into that explain what carbon

2:04

dating is and why it

2:07

might not be an accurate means

2:09

of telling how old something is after

2:12

too long. So going into

2:14

the article, it's about how the enormous

2:16

amount of carbon emissions we generate could make

2:18

carbon dating and unreliable means to determine

2:20

the age of certain types of materials.

2:23

But to understand how that's possible, we need

2:25

to know how carbon dating works

2:28

first, So we're gonna

2:30

do a carbon dating one oh one. Now,

2:33

the first thing that we have to talk about is

2:35

carbon fourteen. So the

2:38

fourteen in carbon fourteen tells

2:40

us it's an isotope of carbon. This

2:43

particular isotope must have eight neutrons

2:45

because carbon has six protons.

2:48

You can change the number of neutrons in an

2:50

atom. That's the different types of isotopes

2:53

atoms may have. But you can't change

2:55

the number of protons and atom has without

2:58

changing that element. So carbon had six

3:00

protons, and if you change that number of protons,

3:02

you change the element itself. It acts

3:05

reacts differently in chemical

3:07

operations, and uh is

3:09

no longer carbon. So

3:12

carbon twelve is the most common

3:15

form of carbon that we find. It has

3:17

six protons and six neutrons. Then

3:19

you have carbon thirteen, which is six protons

3:21

and seven neutrons, and both of those are

3:23

stable forms of carbon. That

3:26

means they don't decay. So if you have carbon

3:28

twelve or carbon thirteen, you

3:30

put it in a box and you leave for

3:33

I don't know, two billion years, and

3:35

you come back, you're still gonna have carbon twelve or

3:37

carbon thirteen because they remain stable.

3:40

They do not decay. But carbon fourteen

3:42

is different. It is a radio

3:45

isotope. Radioisotopes

3:47

are also known as radio nucleides,

3:50

and these are isotopes of

3:52

a particular atom that have an unstable

3:55

nucleus. These isotopes undergo

3:57

what we call nuclear decay, and

3:59

in that process they release some excess

4:02

energy in the form of stuff like gamma

4:04

rays and or subatomic particles.

4:08

Carbon fourteen undergoes what is called beta

4:10

decay. So when it decays,

4:13

one of the neutrons in the nucleus spontaneously

4:16

changes into a proton, an electron,

4:19

and an anti neutrino.

4:21

The nucleus gives the boot to the electron

4:23

and the anti neutrino, but the proton

4:26

stays behind, which means the atom no longer

4:28

is a carbon atom. Since again

4:31

we mentioned that atoms depend upon the number

4:33

of protons and the nucleus, so the

4:36

carbon fourteen decays into

4:38

nitrogen fourteen, and

4:41

nitrogen fourteen has seven protons and

4:43

seven neutrons. Also, by

4:45

the way, one of the few stable elements

4:48

that has both an odd number of protons

4:50

and an odd number of neutrons uh,

4:53

and nitrogen fourteen is stable.

4:56

It makes up the vast majority of the nitrogen

4:58

found naturally under Earth, More than of

5:02

the nitrogen found on Earth is nitrogen fourteen.

5:05

So radioactive decay occurs naturally

5:07

within these isotopes, and it's a spontaneous

5:10

occurrence. That's really important to remember.

5:12

Carbon fourteen has a radioactive half life

5:15

of about five thousand, seven hundred

5:17

years. There's some

5:19

confusion about what that means. I find

5:21

in day to day conversations with people who

5:23

haven't had science in a while. You guys

5:25

who have recently had this in science

5:28

class, you're rolling your eyes right now. But for

5:30

adults who have not taken a science

5:32

class in a long time, this might require

5:35

some some refreshing. So,

5:37

half life of five thousand, seven hundred years,

5:40

what does that mean? It means if you have

5:42

a given amount of carbon fourteen, after

5:45

five thousand, seven hundred years or so,

5:48

you'll have only half of

5:50

that carbon fourteen remaining, the other half

5:53

having undergone decay,

5:55

radioactive decay and turning into nitrogen. Now,

5:58

this doesn't mean that all the carbon four team

6:00

will be gone after another five thousand, seven

6:02

hundred years, nor doesn't mean that

6:04

carbon fourteen has a full life

6:06

of eleven thousand, four hundred years or anything

6:08

like that. In fact, what it really means

6:11

is that after another five thousand,

6:13

seven hundred years, half of the remaining

6:15

sample will have decayed, leaving you with about

6:17

a quarter of what you started with. And another

6:19

five thousand, seven hundred years if that means you be

6:21

left with about an eighth of that sample, and so

6:24

on. Carbon fourteen

6:26

exists naturally on Earth in trace

6:28

amounts. Before the nineteen forties,

6:31

the carbon fourteen on Earth was created through

6:33

a natural process. Once

6:35

in a while, cosmic rays, these

6:37

very high energy particles in outer space,

6:40

would collide with an atom in our atmosphere

6:42

or upper atmosphere, and this collision

6:45

would end up emitting a high energy neutron

6:47

that then could collide with nitrogen

6:50

atoms that are also way up there

6:52

in our atmosphere. Now, cosmic

6:54

rays are high energy sub atomic particles.

6:57

They originate outside of our solar system,

6:59

usually are admitted by supernova of

7:02

massive stars, and these sub atomic particles

7:04

are primarily atomic nuclei and

7:06

high energy protons. So this collision

7:09

of the high energy neutron with the nitrogen

7:11

forces a proton to leave

7:14

the nucleus and the in fourteen

7:16

changes to C fourteen. So,

7:18

in other words, nitrogen fourteen turns to carbon

7:20

fourteen. So instead of having seven protons and seven

7:22

neutrons, the new atom has six protons

7:25

and eight neutrons. The proton

7:27

that was broken off from the nucleus zooms

7:30

off with an electron, so you get

7:32

one proton and one electron. That means you have an

7:34

atom of hydrogen. So

7:37

again what's happening is a high

7:39

energy neutron collides

7:41

with nitrogen fourteen, forces

7:43

out a proton. The proton

7:46

and an electron high tail it and honeymoon

7:48

off as hydrogen and

7:50

the incoming neutron joins

7:53

the party, and now you've got carbon fourteen.

7:56

So pre nineteen forties, carbon

7:58

fourteen is rare because of two reasons. It

8:00

undergoes radioactive decay, so over

8:02

time it disappears, and it's produced

8:05

by an event that's not super frequent, though it's

8:07

also not uncommon, so it does happen

8:10

regularly enough that carbon

8:12

fourteen is replenished,

8:15

but it's a very small overall

8:18

percentage of the carbon here on Earth.

8:21

We've got some more to say about carbon dating

8:23

in just a second, but first let's take a quick

8:25

break for our sponsor. Now,

8:34

living things here on Earth absorb

8:37

carbon through various means, and

8:39

some of that carbon is carbon fourteen. So

8:42

it maybe that you know, you

8:44

eat a plant in that plant has some of the carbon

8:46

fourteen in it. Now you have some of the carbon fourteen

8:49

and you and if we know the ratio

8:51

of carbon fourteen to the stable

8:53

form of carbon twelve, we

8:55

can look at materials and analyze them to see

8:57

how the ratio of carbon fourteen to carbon

9:00

twelve in the material stacks up to the

9:02

standard ratio. With living

9:04

things, this becomes a matter of looking at how much

9:06

carbon fourteen is not

9:08

there? All right, That's it's

9:11

a little confusing. Let me explain. So,

9:13

when a living thing is still alive,

9:16

it accumulates carbon at about the same

9:18

rate it loses carbon, so

9:21

carbon cosmic rays produced this carbon

9:23

fourteen frequently enough that the ratio

9:26

between carbon fourteen and carbon twelve remains

9:29

steady, So the percentage of carbon

9:31

fourteen to carbon twelve is fairly

9:33

standardized. But when a living thing

9:36

stops being alive and turns

9:38

into a not living

9:40

anymore thing, it stops

9:43

accumulating carbon, so it

9:45

has the carbon that it has inside of it

9:48

stays. That's it. You're not

9:50

losing anymore. You're not gaining any more except

9:53

for carbon fourteen because carbon

9:55

fourteen undergoes radioactive decay,

9:58

so over time, some of that

10:00

carbon fourteen starts to convert

10:03

to nitrogen. So

10:05

that means if you can look at

10:08

the remains of a living

10:10

thing and detect the ratio

10:12

of carbon fourteen to carbon twelve.

10:15

You can get an idea of how long ago

10:17

it was that it stopped taking in carbon,

10:20

as in, how long ago was it that this

10:22

lip, once living thing died. It

10:25

gets a little more complicated than all that, but here's

10:27

the basic rule. If

10:30

we want to be really precise, here's

10:32

the equation we use to determine

10:34

the age of a sample of material.

10:37

You have an equation where you take

10:39

the natural logarithm of n

10:42

F divided by n o uh

10:44

that in turn is divided by negative

10:46

point six nine three, and then you

10:48

multiply it by t uh

10:51

one half, so one half t the

10:54

natural logarithm is a

10:56

specific logarithm applied to this equation

10:59

and other things as well. N F divided

11:01

and oh actually refers to the percentage

11:04

of carbon fourteen and the sample compared to

11:06

the amount found in living stuff today

11:09

at times one half is the half

11:11

life of carbon, so that's five thousand, seven

11:13

hundred years. So it was a lot easier

11:16

to understand this if we take a specific example. So

11:19

let's say you've got a sample of

11:21

some sort of material and

11:24

you have determined that there is five percent

11:27

of the amount of carbon fourteen in that

11:29

material compared to what you

11:31

would find in something that is alive. Right

11:33

now, so you take a sample

11:36

of a living thing, and then you

11:38

take the sample of the thing you're

11:40

testing. You see that the thing you're testing

11:42

only has five percent of the carbon fourteen you would

11:44

find in living things. That means you would fill

11:46

out the equation with the natural logarithm

11:48

of point zero five divided

11:51

by negative point six nine

11:53

three, and you multiply that that

11:56

result to with five thousand, seven hundred

11:58

years. The natural lug ay them at point zero

12:00

five, by the way, in case you don't want to whip out your calculator,

12:03

is negative two point nine nine

12:06

five seven three to two seven

12:08

three five five. If you divide

12:10

that by negative point six nine three,

12:12

you get four point three to

12:15

two eight four five.

12:18

Don't dial that number. If

12:21

you take that number, the four point three, etcetera,

12:24

and you multiply that by five thousand, seven hundred

12:26

years, you end up with twenty four

12:28

thousand, six hundred forty point two

12:30

years. I mean, the stuff you're looking at died

12:32

somewhere around that time

12:34

frame, give or take thirty two hundred

12:37

years, So somewhere on twenty four thousand,

12:39

six hundred forty years ago is when that thing no

12:41

longer breathed

12:43

or lived, or however you wanted to

12:46

find it. By the way,

12:48

this approach does have a limitation.

12:50

Anything older than sixty thousand years

12:52

is pretty much out of bounds. Carbon fourteen

12:55

just isn't a reliable means of dating that sort of material,

12:57

and we have to rely on other methods so

13:00

and fourteen because of the decay once

13:02

against two very small amounts, it's

13:05

very difficult to narrow it down

13:07

to a specific time, and if it's long enough,

13:10

there won't be any carbon fourteen at all

13:12

all the carbon fourteen will have decayed by

13:14

then. You can't use carbon dating if

13:16

there's no carbon fourteen left. So

13:19

to actually test the carbon fourteen concentration,

13:22

you first have to take the sample, uh

13:25

whatever object it might be. You have to

13:27

remove part of it, and typically

13:30

you would apply some chemicals to the material, usually

13:32

a very strong acid wash and a strong

13:34

base wash. That's to remove

13:37

all the contaminating materials that

13:39

could end up giving you false

13:42

readings on carbon fourteen. Then

13:44

you would burn the sample within a

13:46

glass container to capture

13:48

the carbon dioxide that is emitted

13:51

when you burn the material. And

13:53

then you would analyze the carbon dioxide

13:56

to find out the concentration of carbon

13:58

fourteen. So you can see that this

14:00

approach has a big drawback. It

14:02

ends up damaging whatever it is you

14:04

are attempting to date in the first place.

14:07

And that's why some particularly high valued

14:09

items go without being tested, because

14:11

the perception is that even a small sample

14:14

of that original piece would

14:16

be too much damage to to uh

14:20

make on this item. So certain

14:22

items are considered very precious and

14:24

there's a big resistance to using carbon

14:26

dating because by definition, you're

14:28

going to be damaging the material. Now,

14:31

there's several lines of research they're

14:33

exploring possible non destructive means

14:35

of using radiocarbon dating. There's

14:37

one that uses plasma oxidation

14:40

and the use of non destructive washes

14:42

to clean samples of those contaminating

14:45

humic acids, which would lead

14:48

to errors if they remain behind. But

14:50

those are still largely in the testing phase

14:53

and aren't the common means of using

14:55

carbon dating. Also, keep in mind that

14:57

we use this method to estimate the date

15:00

of things made from organic materials,

15:02

like the Dead Sea scrolls, but

15:04

this estimation is based upon when the

15:06

materials were harvested So, in other

15:08

words, whenever the living thing that the

15:11

materials came from stopped being alive, it

15:14

doesn't tell us the date of when the artifact

15:16

was actually produced. So it's possible

15:19

that you could come across an artifact like

15:21

a scroll, and you use

15:23

carbon dating on it and find out that

15:25

the scroll material is two

15:27

thousand years old, meaning two thousand years

15:29

ago whatever the scroll was

15:31

made out of stopped living,

15:34

But it doesn't tell you about the contents

15:36

written in the scroll. It's possible

15:39

that the contents were added to the scroll

15:42

much after the living thing

15:44

stopped being alive. Still, it's

15:46

a pretty good bet that the two are within

15:48

the same neighborhood of time, rather than

15:51

someone held onto blank scrolls for a

15:53

few centuries before finally jotting something

15:55

down. All right,

15:57

it's all this is cool, But how did

15:59

we even figure out radio

16:01

Carbon dating would be a possible way

16:03

of figuring out how old something

16:06

is. Well, some early discoveries were made

16:08

in the nineteen thirties at the Lawrence Radiation

16:10

Laboratory in Berkeley, and you probably

16:12

remember that if you've been listening to tech stuff. It

16:15

factored heavily into the discussion I had with Ben

16:17

Boland about the Manhattan Project. So

16:20

Franz Curry, an American

16:22

physicist, observed something really interesting

16:25

when he irradiated a cloud of air

16:27

in a cloud chamber. He used

16:29

neutrons to UH to irradiate

16:32

that cloud, and he saw proton

16:35

recoil tracks that indicated something

16:38

was losing protons. So he concluded

16:40

that the neutrons that he was using

16:43

were colliding with nitrogen fourteen and

16:45

producing what was believed to be a

16:47

form of carbon as a result, with

16:50

hydrogen being the other product of this collision.

16:52

His work was further explored by physicists

16:55

like Tom W. Bonner, W.

16:57

M. Brubaker, W. J. Burcham, and

17:00

Maurice gold Hauber. Now

17:02

collectively, this laid the foundation for the simple

17:04

equation of a high energy neutron plus

17:07

nitrogen fourteen produces one

17:09

hydrogen atom and one carbon fourteen

17:11

atom. Then you had Narrico Fermi.

17:14

We talked about him in the Manhattan Project, and

17:17

his work showed that the cross section of

17:19

a nitrogen fourteen atom was much larger

17:21

than other materials, and that suggested

17:24

that neutron and nitrogen

17:26

collisions might happen fairly regularly in

17:28

nature as long as there were a supply

17:31

of high energy neutrons. All

17:33

right, we got a little bit more about carbon dating,

17:35

and then what's It's back to reality

17:38

for me? I guess so

17:47

Sage Korff, who was a physicist who

17:49

was born in Finland and whose family

17:52

immigrated to the United States in the early twentieth

17:54

century, he discovered the phenomenon

17:56

that cosmic rays interact

17:58

with atoms and produce high energy neutrons

18:01

in the upper atmosphere. So Pharem's

18:03

prediction and course observation,

18:06

we're starting to kind of coalesce

18:09

here. The observations convinced scientists

18:11

that the neutrons themselves were not cosmic

18:13

rays, because the neutrons had a

18:15

lifespan of just eighteen minutes, and

18:17

therefore a neutron wouldn't be

18:19

able to survive the long trip through space.

18:22

They must have been something else first, so

18:25

they said the neutrons had to be a byproduct

18:27

of another interaction. A cosmic

18:29

ray must be interacting with something in the atmosphere.

18:32

That interaction caused this high energy

18:35

neutron to be emitted, and Quarter hypothesized

18:37

that these neutrons could then interact with nitrogen

18:39

fourteen to produce carbon fourteen in the

18:42

upper atmosphere. Now,

18:44

it was Willard F. Libby who came up

18:46

with the idea that since carbon fourteen

18:48

is generated at a steady rate due to cosmic

18:50

ray interactions in our atmosphere, you should

18:53

be able to use it to measure

18:55

how long something has been dead. Libby

18:58

would measure the value of carbon fourteen's half

19:00

life at five thousand, five hundred

19:02

sixty eight years, give or take thirty years,

19:04

which became known as the Libby half

19:06

life. And Libby himself would be awarded

19:09

the Nobel Prize in nineteen sixty

19:11

for his work in radiocarbon dating. All

19:14

right, so that's the history of radiocarbon dating

19:16

and generally how radiocarbon dating works. So

19:19

why is it in trouble or what could possibly

19:22

be causing confusion with radiocarbon

19:24

dating. Well, there are two big things we need

19:26

to talk about, and one was one

19:29

that I've alluded to a couple of times. I mentioned

19:31

that, you know, pre nineteen

19:33

forties, you had a certain level

19:36

of carbon fourteen that was pretty

19:38

standard, but the nuclear

19:40

age really messed things up for us.

19:42

They made carbon fourteen dating a

19:44

bit tricky. Starting in the nineteen forties, we

19:46

began testing nuclear bombs. Now,

19:49

these bombs released a lot of energy upon exploding,

19:52

partly in the form of high energy neutrons.

19:54

You could probably see where this is going. Some of

19:56

those high energy neutrons ended up

19:58

interacting with night jan fourteen atoms,

20:01

which meant that it produced carbon fourteen

20:03

atoms as a result. So the

20:05

concentration of carbon fourteen increased

20:09

in the wake of nuclear bomb

20:11

testing. So anything that died

20:13

after the nineteen forties actually has a

20:15

higher concentration of carbon fourteen

20:17

than the stuff that died before the nineteen

20:20

forties did even at

20:22

the time of death. According to Professor Nalini

20:25

nod Karnie of the Evergreen State College,

20:27

the nineteen fifties saw a one hundred

20:30

percent spike in carbon

20:32

fourteen coming into the atmosphere. In

20:34

nineteen sixty three, the United States

20:37

and Russia agreed to stop above

20:39

ground nuclear testing, and the levels

20:41

of carbon fourteen in the atmosphere gradually dropped

20:43

down to their normal levels. But that means

20:45

there's a blip in the carbon fourteen

20:48

radar between the nineteen forties and nineteen

20:50

sixty three. So if you put yourself in

20:52

the shoes of a future archaeologist.

20:55

Radio carbon dating becomes unreliable

20:57

because the levels of carbon fourteen could be

20:59

decept tip. If the thing you're measuring died

21:02

during the era of nuclear testing, it

21:04

might appear to be younger than

21:06

you thought because there's a higher concentration

21:08

of carbon fourteen in its sample

21:11

than you otherwise would have expected.

21:13

So it may seem that something died

21:16

in twenty fifteen

21:18

as opposed to nineteen sixty three.

21:20

That's just an example. Now to

21:22

the article that prompted this episode in the first

21:25

place, that's a different case.

21:27

Researchers published a study in the Proceedings

21:29

of the National Academy of Sciences about

21:31

how the use of fossil fuels is

21:34

further making radiocarbon dating less

21:36

reliable, and this time it's

21:38

not an excess of carbon fourteen.

21:40

It's actually the opposite problem. Fossil

21:42

fuels have no carbon fourteen

21:45

in them because they are fossil

21:47

fuels. This is billions of

21:50

years old, so they're far

21:52

too old for any carbon fourteen to remain.

21:54

Remember that carbon fourteen is decaying

21:56

over time and turning into nitrogen,

21:58

so eventually all of those carbon

22:01

fourteen atoms decay.

22:03

So burning a fossil fuel create releases

22:05

carbon dioxide, and the carbon in that CEO

22:08

two has no carbon fourteen and it's all

22:10

carbon twolve carbon thirteen. So

22:12

the more fossil fuels we burn, the more

22:15

we dilute the concentration of carbon

22:17

fourteen that's in the atmosphere. So

22:19

stuff from the nuclear age tends to

22:21

look younger than it really is because

22:23

of the higher concentration of carbon fourteen. Stuff

22:26

from the later ages of fossil

22:28

fuel use will look older

22:30

than they really are because carbon fourteen

22:32

has been diluted. So, according to the

22:34

study, fresh organic material

22:37

in twenty fifty would contain the same

22:39

amount of carbon fourteen relative to

22:41

carbon twelve as something dating

22:43

from ten fifty.

22:46

So you have a thousand years

22:48

of doubt in any radio carbon

22:50

dated samples. You

22:53

would look at the two samples if you

22:55

if all you had were miniscule

22:57

samples of two things and one of them was a

22:59

T shirt that was made

23:01

in and another was a

23:04

piece of cloth that dated

23:06

from ten fifty, and you did radiocarbon

23:08

dating, you'd get the same result.

23:11

This is not good if you are trying to figure

23:14

out how old something is

23:17

Heather Graven, who authored the study

23:19

on fossil fuel emissions and the effect on

23:21

radiocarbon dating, says that if we were to

23:23

reduce carbon dioxide emissions

23:26

drastically in the very near future, the

23:28

effect on future radiocarbon dating

23:31

would be equivalent to inserting a one year

23:33

error on top of any estimation. If

23:36

we don't drastically reduce

23:38

emissions, that error range will continue

23:40

to grow over time. One

23:43

thing that the concentration of carbon fourteen tells

23:45

us is how much carbon dioxide in the atmosphere

23:47

comes from the burning of fossil fuels.

23:50

So as we see the concentration decrease,

23:52

we know that's because proportionally more

23:55

carbon twelve is being released into the atmosphere,

23:57

diluting the already tiny concentration of carbon

23:59

fourteen. So that's useful for scientists

24:01

who are studying climate change and pollution.

24:05

That's not exactly a happy story, is it. So

24:09

what are our options if carbon

24:11

dating becomes unreliable,

24:13

Well, that depends on what you're trying to analyze.

24:16

If you're looking at inorganic stuff

24:18

like rocks, you don't need to use carbon fourteen

24:20

in the first place. That would be pretty much

24:22

useless. You would use something else like potassium

24:25

argon dating, which is useful to

24:27

estimate the age of rocks that are a hundred thousand

24:29

years old or younger. And if that's

24:31

not a big enough range, you can actually use uranium

24:34

lead dating, and that will let you

24:36

estimate rocks between one point

24:38

four and five million years old.

24:41

There's a lot of different options if you're trying to

24:43

date stuff. When it comes to organic materials,

24:45

however, it's a lot more tricky. Radio carbon

24:47

was a great tool, but

24:50

if it becomes unreliable, we're gonna have to

24:53

use other methods like contextual clues

24:56

and other items that

24:58

are helping us connect

25:01

things to dates. So

25:03

this is a big problem. I guess

25:05

you could argue that's a big

25:07

problem for future generations and

25:09

perhaps the records we leave behind

25:12

now are so uh

25:16

so complete, they're so

25:18

voluminous, I guess is the best word. That

25:21

future generations will likely have more

25:23

than enough material to determine when

25:26

something originated from our

25:28

time versus earlier times.

25:30

But the point being that the

25:32

way we're interacting with our world

25:35

is changing. This fundamental

25:39

ratio of carbon fourteen to carbon

25:41

twelve, and that

25:43

means that a really brilliant means

25:46

of determining how old something is is

25:48

not really going to be an

25:50

accurate measure for very much longer.

25:54

So it's kind of a bummer. Obviously

25:56

for things that are much much much

25:58

older. UH will at least

26:00

in the short term, not be that big

26:02

of a deal, especially if we can relate it

26:05

to other items that we

26:07

we already know the age of those items.

26:10

It won't be as destructive as saying

26:12

we can never use radio carbon dating again. We

26:15

just have to keep that changing

26:18

ratio of carbon fourteen to carbon twelve

26:21

in mind so that we make sure we're

26:23

making accurate measurements. I hope

26:25

you enjoyed that classic episode of tech Stuff.

26:27

Again, my apologies. I've got

26:29

a lot of things I wish I could have talked about, like

26:32

the fact that there's now a patent

26:34

for a retractable lightsaber

26:37

blade thing. I

26:39

really want to talk more about that, so maybe

26:42

next week. But in the meantime,

26:44

if you have any suggestions for topics

26:46

I should tackle on tech Stuff, let me

26:48

know. Send me a message on Twitter. The

26:51

handle is text stuff h s W.

26:54

I'll talk to you again really

26:56

soon. Yeah. Text

27:02

stuff is an I heart radio production

27:04

For more podcasts from I heart Radio,

27:06

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27:08

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27:10

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