1
00:00:01,560 --> 00:00:04,760
Speaker 1: Welcome to Stuff from the Science Lab from how stuff

2
00:00:04,760 --> 00:00:16,200
Speaker 1: works dot com. Hey guys, and welcome to the podcast.

3
00:00:16,320 --> 00:00:18,320
Speaker 1: This is Alice and Madam of the science editor how

4
00:00:18,360 --> 00:00:20,840
Speaker 1: stuff works dot com. And this is Robert Land, science

5
00:00:20,840 --> 00:00:23,480
Speaker 1: writer at how stuff works dot com. Today we are

6
00:00:23,520 --> 00:00:27,400
Speaker 1: talking about carbon dating. This comes to us compliments of

7
00:00:27,520 --> 00:00:32,080
Speaker 1: one math Frederick in our video department, who requested a

8
00:00:32,080 --> 00:00:35,040
Speaker 1: podcast on carbon dating. And Robert and I are always

9
00:00:35,080 --> 00:00:38,760
Speaker 1: happy to oblige, are we not. We are send us requests,

10
00:00:38,800 --> 00:00:41,880
Speaker 1: we will, we'll try and do them. Carbon dating actually

11
00:00:41,880 --> 00:00:44,120
Speaker 1: proved to be a little complicated, so we're gonna take

12
00:00:44,159 --> 00:00:48,159
Speaker 1: it low and slow. As producer Jerry said today, So

13
00:00:48,520 --> 00:00:51,880
Speaker 1: what is carbon dating used for? Basically, it's just a

14
00:00:52,080 --> 00:00:55,840
Speaker 1: it's just a method of dating any any organic matter,

15
00:00:55,920 --> 00:00:58,760
Speaker 1: any bone, maybe a skull that you happened to dig

16
00:00:58,840 --> 00:01:02,880
Speaker 1: up in your backyard, cloth, would plant fibers, any anything

17
00:01:02,880 --> 00:01:06,280
Speaker 1: of that nature. And carbon dating can be used to

18
00:01:06,280 --> 00:01:10,280
Speaker 1: determine the age of objects up to about fifty years old.

19
00:01:10,640 --> 00:01:12,680
Speaker 1: But that the key is that some part of it

20
00:01:12,720 --> 00:01:15,600
Speaker 1: has to have been living at some point in the past, right,

21
00:01:15,760 --> 00:01:17,440
Speaker 1: That is the key. So like I couldn't take like

22
00:01:17,480 --> 00:01:20,520
Speaker 1: an iron sword necessarily unless it had like some sort

23
00:01:20,520 --> 00:01:24,839
Speaker 1: of organic wrapper around it, or like a hilt or something. Right, Yes, yes,

24
00:01:24,880 --> 00:01:29,720
Speaker 1: that is correct and commendating could potentially figure out the

25
00:01:29,720 --> 00:01:31,800
Speaker 1: age of an object up to a hundred thousand years

26
00:01:31,800 --> 00:01:35,920
Speaker 1: if you happen to have a particle accelerator. Handy, But

27
00:01:36,000 --> 00:01:39,119
Speaker 1: how exactly and who? Who's who's interested in doing all

28
00:01:39,120 --> 00:01:41,560
Speaker 1: this carbon dating? Like why why do we care? It's

29
00:01:41,560 --> 00:01:44,559
Speaker 1: good to know how old things are. So. Carbon dating

30
00:01:44,640 --> 00:01:47,600
Speaker 1: actually has an interesting history when it comes to religion

31
00:01:47,640 --> 00:01:51,760
Speaker 1: and religious artifacts. Yeah, the most famous being the shroud

32
00:01:51,800 --> 00:01:54,200
Speaker 1: of Turin. For those of you don't remember, this is

33
00:01:54,760 --> 00:01:58,680
Speaker 1: allegedly the burial cloth of Jesus Christ, Jesus of Nazareth,

34
00:01:58,960 --> 00:02:03,520
Speaker 1: after he's crucified, laid in the tomb, he has this

35
00:02:03,760 --> 00:02:06,760
Speaker 1: shroud over him. It has become an item of legend,

36
00:02:07,320 --> 00:02:11,120
Speaker 1: a holy relic passed down through the centuries. Whether it's

37
00:02:11,160 --> 00:02:14,120
Speaker 1: the same are you know article that's passed down through

38
00:02:14,120 --> 00:02:17,639
Speaker 1: the centuries or not, that's that's debatable. Um. And there

39
00:02:17,639 --> 00:02:20,080
Speaker 1: has been a lot of debate about the Shroud of Turan.

40
00:02:20,440 --> 00:02:23,560
Speaker 1: Even if you don't get into the whole, into the

41
00:02:23,560 --> 00:02:26,720
Speaker 1: whole carbon dating thing, which doesn't come along until you

42
00:02:26,720 --> 00:02:30,959
Speaker 1: know the modern era. Um, you still encounter a lot

43
00:02:31,000 --> 00:02:34,079
Speaker 1: of disagreement. Just just to run by how everything works

44
00:02:34,080 --> 00:02:37,560
Speaker 1: real quick. Like I said, Jesus dies cloud was on

45
00:02:37,639 --> 00:02:40,040
Speaker 1: him right leaves this print of him and this this

46
00:02:40,120 --> 00:02:43,040
Speaker 1: the deal with like it looks like like a bearded man.

47
00:02:43,200 --> 00:02:45,240
Speaker 1: If if you look at it, it's like this like

48
00:02:45,400 --> 00:02:48,840
Speaker 1: stains of a bearded man, and there's some bloodstains on it, etcetera.

49
00:02:49,200 --> 00:02:53,840
Speaker 1: It mysteriously disappeared when Constantinople was sacked in twelve before

50
00:02:54,480 --> 00:02:58,120
Speaker 1: hearing the Fourth Crusade. Then in thirteen fifty seven, following

51
00:02:58,120 --> 00:03:01,519
Speaker 1: the Crusades, it shows up in a French church. Um.

52
00:03:01,639 --> 00:03:03,600
Speaker 1: Then just in a couple of years, it was already

53
00:03:03,600 --> 00:03:07,760
Speaker 1: getting critics from inside the church. Yeah, a bishop in

54
00:03:08,160 --> 00:03:12,080
Speaker 1: thirteen fifty nine, you know, criticized and said this can't

55
00:03:12,080 --> 00:03:15,000
Speaker 1: you know, be the real article. Um. And he wasn't

56
00:03:15,000 --> 00:03:17,160
Speaker 1: even on fire or anything. This is like an actual

57
00:03:17,480 --> 00:03:19,360
Speaker 1: like this is a good bishop, not you know heretic

58
00:03:19,440 --> 00:03:23,080
Speaker 1: or anything. Um. And anybody end up getting moved to

59
00:03:23,280 --> 00:03:26,720
Speaker 1: uh Turin and it's been there since fifty So have

60
00:03:26,800 --> 00:03:29,280
Speaker 1: they done some carbon dating on the on the shroud, Yes,

61
00:03:29,360 --> 00:03:31,519
Speaker 1: they have done some carbon dating on the shroud. Of course,

62
00:03:31,520 --> 00:03:33,640
Speaker 1: it had to wait until we had the technology to

63
00:03:33,720 --> 00:03:38,400
Speaker 1: do it. Uh. But in Um they cut a corner

64
00:03:38,680 --> 00:03:40,600
Speaker 1: off of the shroud, all right, and then they cut

65
00:03:40,600 --> 00:03:43,040
Speaker 1: that corner in half. And then they took one of

66
00:03:43,040 --> 00:03:46,040
Speaker 1: those halves and they divided into three pieces, all right,

67
00:03:46,320 --> 00:03:49,720
Speaker 1: and they sent one piece to to a scientist in Oxford,

68
00:03:50,080 --> 00:03:52,720
Speaker 1: one piece to scientist in Zurich, and one piece to

69
00:03:52,800 --> 00:03:56,480
Speaker 1: scientist in Arizona. And was this too, maybe to assure

70
00:03:56,560 --> 00:04:00,000
Speaker 1: some level of objectivity or you know, independently verified by

71
00:04:00,080 --> 00:04:01,840
Speaker 1: three labs. Yeah, that was the idea. And I think

72
00:04:01,880 --> 00:04:03,800
Speaker 1: originally they wanted to send it to more like I

73
00:04:03,840 --> 00:04:05,800
Speaker 1: think it was originally they're gonna go to five or something,

74
00:04:06,200 --> 00:04:08,040
Speaker 1: but they ended up just doing three. And yeah, they're

75
00:04:08,040 --> 00:04:11,800
Speaker 1: they're they The Catholic Church has been historically kind of

76
00:04:11,960 --> 00:04:14,120
Speaker 1: stinge you with handing out the pieces. I mean, for

77
00:04:15,120 --> 00:04:18,799
Speaker 1: understandable reasons. It's because if it's if it's really the

78
00:04:18,880 --> 00:04:22,520
Speaker 1: you know, the burial cloth of the Son of God,

79
00:04:22,880 --> 00:04:24,880
Speaker 1: you know, then it's this is an important thing. You

80
00:04:24,880 --> 00:04:27,200
Speaker 1: can't just be clipping it up every time somebody wants to,

81
00:04:27,520 --> 00:04:30,039
Speaker 1: you know, do some sort of analysis on it. In fact,

82
00:04:30,080 --> 00:04:32,920
Speaker 1: they rarely even show it to the public. Uh. It

83
00:04:33,040 --> 00:04:35,200
Speaker 1: last went on display in the year two thousand and

84
00:04:35,240 --> 00:04:39,800
Speaker 1: it's not gonna go on display again until um. And Also,

85
00:04:40,600 --> 00:04:42,159
Speaker 1: I think this has come up before when we've talked

86
00:04:42,360 --> 00:04:46,680
Speaker 1: talked about the study of anything that's of of religious value.

87
00:04:46,720 --> 00:04:50,480
Speaker 1: When it's a faith and science meeting, it's like, what

88
00:04:50,480 --> 00:04:53,640
Speaker 1: what's the you know, what's the real gain for the church? Right,

89
00:04:53,960 --> 00:04:56,800
Speaker 1: Like everybody's supposed to be believing in things based on

90
00:04:56,800 --> 00:04:59,039
Speaker 1: on faith, right, Not because the New Scientist has an

91
00:04:59,120 --> 00:05:02,880
Speaker 1: article about it. It's say, this was totally laying on

92
00:05:03,000 --> 00:05:06,760
Speaker 1: Jesus several centuries back. But anyway, that's a whole that's

93
00:05:06,760 --> 00:05:09,440
Speaker 1: a whole tangent. So anyway, the three studies came back,

94
00:05:10,040 --> 00:05:13,120
Speaker 1: all of them had performed carbon dating, and they concluded

95
00:05:13,160 --> 00:05:17,320
Speaker 1: that the cloth was woven between twelve sixty d Okay,

96
00:05:17,320 --> 00:05:19,159
Speaker 1: So what do these states mean? That means as a

97
00:05:19,200 --> 00:05:24,400
Speaker 1: problem because Jesus was long gone by that point, um.

98
00:05:24,440 --> 00:05:28,479
Speaker 1: And it means that would position the shroud around the

99
00:05:28,560 --> 00:05:32,880
Speaker 1: time of its earliest documented appearance. So this could have

100
00:05:32,920 --> 00:05:34,839
Speaker 1: been a forgery of fake Yeah, that that's the the

101
00:05:34,920 --> 00:05:38,880
Speaker 1: argument that it's some that's basically a medieval forgery, and

102
00:05:38,880 --> 00:05:41,000
Speaker 1: of course that then introduces a whole host of other

103
00:05:41,360 --> 00:05:43,560
Speaker 1: you know, questions like who's who forged it, how did

104
00:05:43,560 --> 00:05:45,520
Speaker 1: they forge it? And you know, people go crazy with

105
00:05:45,560 --> 00:05:47,760
Speaker 1: these ideas well. Given that the shroud has passed hands

106
00:05:47,760 --> 00:05:52,120
Speaker 1: so many times, isn't it possible that the shroud was contaminated. Yes,

107
00:05:52,200 --> 00:05:56,400
Speaker 1: that's one theory. Mainly there was a fire in A

108
00:05:56,480 --> 00:06:01,040
Speaker 1: fifty two and it was apparently partially damaged at that point,

109
00:06:01,160 --> 00:06:05,400
Speaker 1: and people, uh, some of the supporters, especially USA physicist

110
00:06:05,520 --> 00:06:08,600
Speaker 1: John Jackson, who has been heavily involved in the study

111
00:06:08,640 --> 00:06:12,800
Speaker 1: of the shroud UM he maintains that that that this

112
00:06:12,920 --> 00:06:17,920
Speaker 1: damage could have offset the the the carbon dating UM. Yeah.

113
00:06:17,920 --> 00:06:21,280
Speaker 1: He says that elevated levels of carbon monoxide could then

114
00:06:21,320 --> 00:06:25,760
Speaker 1: have skewed the carbon four te dating by hundred years.

115
00:06:26,320 --> 00:06:29,560
Speaker 1: His theory suggests that that only eight two percent contamination

116
00:06:29,640 --> 00:06:33,960
Speaker 1: is enough to skew carbon dating results by fifteen hundred years.

117
00:06:34,760 --> 00:06:37,280
Speaker 1: So that's one theory. Then there are also arguments that

118
00:06:37,320 --> 00:06:40,719
Speaker 1: cotton patches were added to it in the sixteenth century,

119
00:06:41,240 --> 00:06:45,080
Speaker 1: and so again you have you know, um um more

120
00:06:45,800 --> 00:06:53,360
Speaker 1: more recent material um unbalancing the measurements. Then understand they

121
00:06:53,720 --> 00:06:57,560
Speaker 1: took some samples, they analyze some seed and plant samples

122
00:06:57,560 --> 00:06:59,800
Speaker 1: that they found on the shroud, and this actually seemed

123
00:06:59,800 --> 00:07:06,240
Speaker 1: to intradict the findings that it was a forgery. So yeah,

124
00:07:06,279 --> 00:07:08,080
Speaker 1: it gets really heated. And then there's I mean, there

125
00:07:08,080 --> 00:07:10,760
Speaker 1: are people should say, well, hey, these materials couldn't have

126
00:07:10,760 --> 00:07:13,400
Speaker 1: come from this region, or or they you know, or

127
00:07:13,600 --> 00:07:17,520
Speaker 1: or critics that site what we know about burial practices

128
00:07:17,560 --> 00:07:21,480
Speaker 1: at the time, um et cetera. It's it's a heated argument.

129
00:07:21,560 --> 00:07:23,760
Speaker 1: You can really you can really go nuts with this one.

130
00:07:24,240 --> 00:07:26,720
Speaker 1: But that brings us back to carbon dating, though, Um,

131
00:07:26,800 --> 00:07:30,480
Speaker 1: you know, what's what is actually going on in the process. Well,

132
00:07:30,600 --> 00:07:34,080
Speaker 1: let's let's take it to outer space. Okay. It starts

133
00:07:34,120 --> 00:07:37,040
Speaker 1: with some cosmic rays zipping in from outer space into

134
00:07:37,040 --> 00:07:39,800
Speaker 1: the Earth's atmosphere. And these guys are zipping in so

135
00:07:39,880 --> 00:07:43,120
Speaker 1: fast it's like roughly the speed of light. So a

136
00:07:43,120 --> 00:07:45,240
Speaker 1: lot of these rays are entering the atmosphere at any

137
00:07:45,280 --> 00:07:50,440
Speaker 1: given moment, say right now, and the protons of these

138
00:07:50,480 --> 00:07:53,480
Speaker 1: speedy rays are interacting with the nitrogen in the atmosphere.

139
00:07:53,880 --> 00:07:57,160
Speaker 1: And you remember that nitrogen is is pretty um, it's

140
00:07:57,160 --> 00:08:00,160
Speaker 1: pretty popular in our in our planet's atmosphere composed is

141
00:08:00,160 --> 00:08:04,800
Speaker 1: about seventy of Earth's atmosphere. So you have these rays

142
00:08:04,840 --> 00:08:07,320
Speaker 1: coming in bombarding the Earth at any moment, and you

143
00:08:07,360 --> 00:08:10,080
Speaker 1: have all this nitrogen, so you have a good chance

144
00:08:10,120 --> 00:08:12,280
Speaker 1: that the nitrogen and the cosmic rays are going to

145
00:08:12,360 --> 00:08:16,640
Speaker 1: meet up, and they do, and it's it's an exciting

146
00:08:16,680 --> 00:08:20,000
Speaker 1: meeting as far as these things go. So exciting that

147
00:08:20,040 --> 00:08:24,600
Speaker 1: the nitrogen it's prompted to lose a proton, gain a neutron.

148
00:08:25,120 --> 00:08:29,560
Speaker 1: And assume the identity of carbon fourteen, the carbon fourteen

149
00:08:29,600 --> 00:08:33,720
Speaker 1: that's used in carbon fourteen dating. Okay, in carbon fourteen

150
00:08:33,880 --> 00:08:38,240
Speaker 1: is an unstable form or isotope of carbon. So let's

151
00:08:38,280 --> 00:08:41,120
Speaker 1: take it back for a second. Cosmic rays are coming in,

152
00:08:42,200 --> 00:08:46,360
Speaker 1: they're hitting nitrogen. Nitrogen is being transformed into a carbon fourteen.

153
00:08:46,880 --> 00:08:50,319
Speaker 1: So scientists think that the rate of carbon fourteen and

154
00:08:50,960 --> 00:08:53,920
Speaker 1: in the atmosphere is constant. The rate of production of

155
00:08:53,920 --> 00:08:57,160
Speaker 1: this carbon fourteen is constant. Is a living organism, I'm

156
00:08:57,160 --> 00:08:59,360
Speaker 1: going to have more or less that constant rate inside

157
00:08:59,400 --> 00:09:03,600
Speaker 1: me alive, Yes, exactly. So, Luke, we were just talking

158
00:09:03,600 --> 00:09:09,320
Speaker 1: about carbon fourteen is radioactive and what does radioactivity mean? Okay, right,

159
00:09:10,080 --> 00:09:12,280
Speaker 1: you know, and and when you're talking about elements like

160
00:09:12,640 --> 00:09:15,640
Speaker 1: uranium or you know, carbon fourteen. It's just indicating that

161
00:09:16,920 --> 00:09:19,960
Speaker 1: an isotope is going to be spontaneously emitting these energetic

162
00:09:20,040 --> 00:09:24,920
Speaker 1: particles like you know, an electron, and the atoms nucleus

163
00:09:24,960 --> 00:09:28,880
Speaker 1: is going to be disintegrating or decaying or changing. The

164
00:09:29,000 --> 00:09:30,880
Speaker 1: rate of which this change takes place is called the

165
00:09:30,880 --> 00:09:34,240
Speaker 1: half life. A lot of times you'll hear scientists talking

166
00:09:34,240 --> 00:09:37,280
Speaker 1: about half lives and conjunction with radioactivity. So a half

167
00:09:37,320 --> 00:09:38,960
Speaker 1: life is the time that it takes for half of

168
00:09:39,000 --> 00:09:43,240
Speaker 1: the atoms of a radioactive substance to disintegrate. Yeah, so

169
00:09:43,360 --> 00:09:45,520
Speaker 1: in the case of carbon fourteen, that half life is

170
00:09:46,000 --> 00:09:49,960
Speaker 1: five thousand, seven hundred and thirty years. So now you

171
00:09:50,000 --> 00:09:52,240
Speaker 1: know a little bit about the personality so to speak

172
00:09:52,240 --> 00:09:54,120
Speaker 1: of carbon fourteen. Let's talk about how it makes it

173
00:09:54,160 --> 00:09:58,120
Speaker 1: into plants and animals. So growing plants, as you guys know,

174
00:09:58,240 --> 00:10:02,360
Speaker 1: taking carbon dioxide all the time, they use the carbon,

175
00:10:02,400 --> 00:10:05,480
Speaker 1: get rid of the oxygen, and they're not averse to

176
00:10:05,520 --> 00:10:08,320
Speaker 1: take it in a little carbon fourteen too. In fact,

177
00:10:08,400 --> 00:10:09,960
Speaker 1: anything that eats a plant is going to take in

178
00:10:10,000 --> 00:10:13,600
Speaker 1: some carbon fourteen. Like us, you like to eat plants, right,

179
00:10:14,440 --> 00:10:17,320
Speaker 1: I'm rather fond of them. The idea behind carbon dating

180
00:10:17,360 --> 00:10:19,920
Speaker 1: is that the percentage of carbon fourteen found in living

181
00:10:19,960 --> 00:10:23,559
Speaker 1: things is the same as in the atmosphere. So your

182
00:10:23,679 --> 00:10:26,720
Speaker 1: ratio of carbon fourteen to carbon twelve, which is the

183
00:10:26,840 --> 00:10:29,400
Speaker 1: stable form of carbon, is going to say the same

184
00:10:29,440 --> 00:10:32,520
Speaker 1: while you're alive. So when a plant or animal dies

185
00:10:32,520 --> 00:10:36,160
Speaker 1: there it stops taking in carbon. Right, But remember your

186
00:10:36,160 --> 00:10:38,800
Speaker 1: carbon fourteen is all crazy and it's radioactive, so it's

187
00:10:38,800 --> 00:10:41,240
Speaker 1: going to go on being radioactive and it's going to

188
00:10:41,360 --> 00:10:45,760
Speaker 1: go on to decay into stable carbon. So the idea

189
00:10:45,840 --> 00:10:49,360
Speaker 1: behind carbon dating is actually pretty simple. Scientists look at

190
00:10:49,360 --> 00:10:52,040
Speaker 1: the ratio of these two forms of carbon, carbon twelve

191
00:10:52,080 --> 00:10:55,840
Speaker 1: and carbon fourteen in a sample, and then they compare

192
00:10:55,840 --> 00:10:58,240
Speaker 1: it to the ratio and a living organism. So they

193
00:10:58,280 --> 00:11:01,080
Speaker 1: get this ratio in a dead organism, and look at

194
00:11:01,080 --> 00:11:04,160
Speaker 1: this ratio and a living organism. And remember that the

195
00:11:04,280 --> 00:11:07,520
Speaker 1: ratio and a living organism is constant. It stays the same.

196
00:11:08,080 --> 00:11:11,040
Speaker 1: So if you compare the two, you can find out

197
00:11:11,080 --> 00:11:13,439
Speaker 1: how much time has elapsed. And why can we figure

198
00:11:13,440 --> 00:11:18,200
Speaker 1: out how much time has elapsed? Because we can good

199
00:11:18,240 --> 00:11:20,000
Speaker 1: by looking at like you just said, by looking at

200
00:11:20,000 --> 00:11:24,000
Speaker 1: the balance between carbon twelve and carbon fourteen. So by

201
00:11:24,040 --> 00:11:26,080
Speaker 1: looking at this difference between the two ratio as we

202
00:11:26,120 --> 00:11:28,760
Speaker 1: can tell how old something is because we know the

203
00:11:28,800 --> 00:11:31,319
Speaker 1: half life of carbon fourteen. So this is a pretty

204
00:11:31,320 --> 00:11:34,680
Speaker 1: handy technique to do to have um when you're trying

205
00:11:34,720 --> 00:11:37,240
Speaker 1: to determine the age of whatever organic object you happen

206
00:11:37,280 --> 00:11:42,720
Speaker 1: to dig up on your archaeological expedition, whatever shroud you

207
00:11:42,760 --> 00:11:46,319
Speaker 1: happen to plunder from Constantinople, you have a random chunk

208
00:11:46,320 --> 00:11:49,800
Speaker 1: of an old bishop or or any kind of profit

209
00:11:49,920 --> 00:11:54,400
Speaker 1: having been laying around. So you know, Actually, the Catholic

210
00:11:54,520 --> 00:11:57,920
Speaker 1: Church did some carbon dating um on the apostle Paul,

211
00:11:59,120 --> 00:12:02,960
Speaker 1: and the results of that seemed to conclude that they

212
00:12:02,960 --> 00:12:05,079
Speaker 1: did in fact belong to him. And Paul, of course

213
00:12:06,200 --> 00:12:08,840
Speaker 1: was one of the two main guys known for spreading

214
00:12:08,840 --> 00:12:12,080
Speaker 1: the Christian faith after Jesus Christ died. So you might wonder,

215
00:12:12,160 --> 00:12:14,920
Speaker 1: I mean, how do we know that carbon fourteen dating works? So,

216
00:12:15,040 --> 00:12:16,960
Speaker 1: like any good scientists, you're not going to just accept

217
00:12:17,000 --> 00:12:19,280
Speaker 1: that carbon fourteen dating works as a method. You're going

218
00:12:19,320 --> 00:12:22,559
Speaker 1: to verify it with with You're gonna check your answers.

219
00:12:23,160 --> 00:12:25,080
Speaker 1: And they have in fact done that. They've used carbon

220
00:12:25,120 --> 00:12:27,800
Speaker 1: fourteen dating on objects whose ages were known, like the

221
00:12:27,800 --> 00:12:31,520
Speaker 1: Dead Sea scrolls. But this relatively cool technique has its

222
00:12:31,559 --> 00:12:35,079
Speaker 1: limitations like anything does. Right, like with the shroud, if

223
00:12:35,080 --> 00:12:38,040
Speaker 1: you have other um, if the sample has been compromised

224
00:12:38,040 --> 00:12:40,920
Speaker 1: at any point in the past. Uh In like with

225
00:12:41,000 --> 00:12:42,839
Speaker 1: the one argument saying that oh, they added some cotton

226
00:12:42,840 --> 00:12:45,839
Speaker 1: packages to the shroud centuries later. Well, now you have

227
00:12:46,920 --> 00:12:49,840
Speaker 1: you have newer material and older material and the balance

228
00:12:49,880 --> 00:12:53,880
Speaker 1: could theoretically be different between the two and throw things off.

229
00:12:54,040 --> 00:12:56,880
Speaker 1: Or you have you know, you have a carbon monoxide

230
00:12:56,880 --> 00:12:59,640
Speaker 1: from a fire. Uh. You know, so you have fresh

231
00:13:00,080 --> 00:13:05,839
Speaker 1: fresh carbon infiltrating the artifact, right carbon contamination. Um. Also,

232
00:13:05,880 --> 00:13:09,040
Speaker 1: you you probably need a large sample size and UM,

233
00:13:09,120 --> 00:13:11,319
Speaker 1: if you're gonna have to bust out, say a particle

234
00:13:11,360 --> 00:13:14,439
Speaker 1: accelerator for your sample, it's it's gonna be pretty price prohibitive.

235
00:13:16,280 --> 00:13:19,160
Speaker 1: And so here's the tricky thing is actually that ratio

236
00:13:19,200 --> 00:13:22,760
Speaker 1: of C fourteen to C twelve isn't constant, although scientists

237
00:13:22,800 --> 00:13:25,400
Speaker 1: have begun to understand how to calibrate for this deviation

238
00:13:25,440 --> 00:13:28,240
Speaker 1: in the ratio. UM. But there is a bit of

239
00:13:28,520 --> 00:13:32,200
Speaker 1: tweaking going on with carbon fourteen dating. And then you

240
00:13:32,240 --> 00:13:35,559
Speaker 1: have stuff like man messing it up. If you factor

241
00:13:35,640 --> 00:13:38,960
Speaker 1: and stuff like ozone layer depletion, then you're gonna have

242
00:13:39,080 --> 00:13:42,040
Speaker 1: more C fourteen forming because you're gonna have more cosmic

243
00:13:42,160 --> 00:13:45,800
Speaker 1: rays coming in and bombarding. And I think that have

244
00:13:45,880 --> 00:13:49,800
Speaker 1: been similar. Um accusation is made about the use of

245
00:13:49,880 --> 00:13:53,400
Speaker 1: nuclear power or the detonation of nuclear armaments could throw

246
00:13:53,440 --> 00:13:56,959
Speaker 1: things off, but generally you want to rely on other

247
00:13:57,000 --> 00:13:59,080
Speaker 1: sources as well. It's a it's a great tool, but

248
00:13:59,160 --> 00:14:01,640
Speaker 1: it's not the the only tool for determining the age

249
00:14:01,640 --> 00:14:04,080
Speaker 1: of an object. Best if you can back it up

250
00:14:04,080 --> 00:14:07,240
Speaker 1: with other other means. So there you haven't Matt. There's

251
00:14:07,240 --> 00:14:11,120
Speaker 1: your podcast on carbon dating. Eat it. If you have

252
00:14:11,160 --> 00:14:13,320
Speaker 1: a question about this cool technology, send us an email

253
00:14:13,440 --> 00:14:15,520
Speaker 1: at science Stuff at how stuff works dot com. We

254
00:14:15,520 --> 00:14:17,880
Speaker 1: also have a whole article about it that's pretty good.

255
00:14:17,960 --> 00:14:22,280
Speaker 1: Is our call, how how carbon dating works? We sure do. Hey,

256
00:14:22,320 --> 00:14:25,200
Speaker 1: so why don't we open up some of that listener mail? Well,

257
00:14:25,240 --> 00:14:27,040
Speaker 1: we will do that, but first I just wanted to

258
00:14:27,040 --> 00:14:30,000
Speaker 1: get to a quick correction that was sent to us

259
00:14:30,000 --> 00:14:33,040
Speaker 1: from Shane and a. Shane has a pretty cool uh

260
00:14:33,240 --> 00:14:36,840
Speaker 1: company called Scales and Tails Utah, and they have awesome motto,

261
00:14:36,920 --> 00:14:39,200
Speaker 1: the motto there is where we say fun with a

262
00:14:39,240 --> 00:14:42,480
Speaker 1: forked tongue. Oh wow, I can't possibly imagine what that

263
00:14:42,520 --> 00:14:45,080
Speaker 1: business consists of. Well, funny, you should ask Robert. It's

264
00:14:45,120 --> 00:14:49,600
Speaker 1: a an entertaining, educational and interactive reptiles show. So they

265
00:14:50,120 --> 00:14:53,400
Speaker 1: go around all that sounds awesome. It is pretty cool.

266
00:14:53,760 --> 00:14:55,480
Speaker 1: I checked it out. I mean, I would like for

267
00:14:55,560 --> 00:14:57,240
Speaker 1: my my daughter to be expected. This is like that

268
00:14:57,320 --> 00:15:01,640
Speaker 1: they bring like lizards to school. And um, Shane from

269
00:15:01,680 --> 00:15:04,680
Speaker 1: Scales and Tails actually at he said he had six

270
00:15:04,760 --> 00:15:10,600
Speaker 1: monitor lizards, I believe. But Shane's correction was in our

271
00:15:10,680 --> 00:15:14,160
Speaker 1: Komodo Dragons podcast if you happen to catch that. Um,

272
00:15:14,200 --> 00:15:16,560
Speaker 1: we did say that Komodo dragons can do a lot

273
00:15:16,600 --> 00:15:19,320
Speaker 1: of cool stuff and they can, but one cool thing

274
00:15:19,360 --> 00:15:23,040
Speaker 1: they cannot do. They cannot unhinge their jaws. They do, however,

275
00:15:23,200 --> 00:15:26,160
Speaker 1: have a pretty flexible jaw. And I really have to

276
00:15:26,200 --> 00:15:28,880
Speaker 1: take part of the blame for this one because I

277
00:15:29,040 --> 00:15:32,160
Speaker 1: usually unhinge my job I'm eating a hamburger or even

278
00:15:32,240 --> 00:15:35,160
Speaker 1: some of the larger sid sliders. You know, I've seen

279
00:15:35,200 --> 00:15:37,720
Speaker 1: you do that, I ask, Yeah, so you know I

280
00:15:37,800 --> 00:15:40,480
Speaker 1: do it, and I figure most people and most animals

281
00:15:40,480 --> 00:15:42,560
Speaker 1: do it, so um, you know that's what I get

282
00:15:42,560 --> 00:15:45,400
Speaker 1: for generalizing. Oh and hey, if you want to check

283
00:15:45,440 --> 00:15:49,400
Speaker 1: out Shane's site, it's www dot scales and tails Utah

284
00:15:49,480 --> 00:15:51,960
Speaker 1: dot com. So there you have a Shane. Thanks for

285
00:15:52,120 --> 00:15:54,440
Speaker 1: alerting us to that correction. All right, now let's open

286
00:15:54,480 --> 00:15:57,120
Speaker 1: that mail. Let's open the mail. This is very exciting.

287
00:16:01,360 --> 00:16:03,680
Speaker 1: So this piece of mail came to us a couple

288
00:16:03,680 --> 00:16:07,320
Speaker 1: of days ago. Hello, Alice, my name is actually Alison,

289
00:16:07,320 --> 00:16:11,280
Speaker 1: but that's okay. This is in the ballpark, Robert and Jerry,

290
00:16:11,400 --> 00:16:15,200
Speaker 1: and Jerry, you spelled your name correctly. I just listened

291
00:16:15,200 --> 00:16:18,400
Speaker 1: to your podcast on t rex Is and the one

292
00:16:18,400 --> 00:16:21,400
Speaker 1: on Komodo Dragons and enjoyed both of them. You guys

293
00:16:21,440 --> 00:16:25,000
Speaker 1: are really good, and I'm really interested in reptiles. While

294
00:16:25,080 --> 00:16:27,680
Speaker 1: on a family vacation, I was too young to remember,

295
00:16:27,920 --> 00:16:32,800
Speaker 1: I was followed for several days by Komodo several days.

296
00:16:32,840 --> 00:16:35,840
Speaker 1: Like I picture it like in a car, like tailing

297
00:16:35,920 --> 00:16:39,000
Speaker 1: them the como behind. Yeah, like they're in a family

298
00:16:39,040 --> 00:16:41,760
Speaker 1: road trip and it's like they look back and Komoto

299
00:16:41,800 --> 00:16:46,920
Speaker 1: and sunglasses cuts back into a diner, continuing, I thought

300
00:16:46,920 --> 00:16:49,440
Speaker 1: that the only in poisonous lizards were the Mexican beated lizard.

301
00:16:49,440 --> 00:16:51,840
Speaker 1: And the Heila Monster. I also wanted to add that

302
00:16:51,880 --> 00:16:54,080
Speaker 1: t rex Is may also have had feathers, which was

303
00:16:54,120 --> 00:16:56,800
Speaker 1: told to me by Professor Prum of Yale. I don't

304
00:16:56,800 --> 00:16:58,680
Speaker 1: know if it was his theory or not that was

305
00:16:58,720 --> 00:17:02,360
Speaker 1: in parens. It seemed interesting and painted the t rex

306
00:17:02,440 --> 00:17:04,840
Speaker 1: Is a sort of giant too. Chicken again, You guys

307
00:17:04,840 --> 00:17:06,960
Speaker 1: are my favorite podcast and we'll keep listening as long

308
00:17:07,000 --> 00:17:12,280
Speaker 1: as you make them. Signed Jack, Los Angeles, aged twelve. Thanks.

309
00:17:12,359 --> 00:17:16,000
Speaker 1: Jack's great. So if you guys have a correction or

310
00:17:16,040 --> 00:17:17,879
Speaker 1: I want to send us a note or tell us

311
00:17:17,880 --> 00:17:20,760
Speaker 1: how we're doing, yeah, or pat us with those suggestions.

312
00:17:20,760 --> 00:17:22,800
Speaker 1: You want to hear about a topic and uh, you

313
00:17:22,840 --> 00:17:25,439
Speaker 1: know you know what to do, send us an email

314
00:17:25,480 --> 00:17:28,440
Speaker 1: at science stuff at how stuff works dot com. That's

315
00:17:28,440 --> 00:17:37,680
Speaker 1: all I got for today. Thanks for listening. For more

316
00:17:37,720 --> 00:17:40,000
Speaker 1: on this and thousands of other topics, is that how

317
00:17:40,040 --> 00:17:43,720
Speaker 1: stuff works dot com. Want more how stuff works, check

318
00:17:43,760 --> 00:17:45,920
Speaker 1: out our blogs on the house stuff works dot com

319
00:17:45,960 --> 00:17:52,880
Speaker 1: home page