1
00:00:08,520 --> 00:00:10,520
Speaker 1: Hey, Daniel, you like having visitors.

2
00:00:10,720 --> 00:00:14,800
Speaker 2: I like having visitors at my university and visitors at home. Sure,

3
00:00:14,840 --> 00:00:15,520
Speaker 2: I like people.

4
00:00:16,280 --> 00:00:18,200
Speaker 1: You like people. How about aliens?

5
00:00:19,960 --> 00:00:22,959
Speaker 2: I would love if aliens send us a message or

6
00:00:23,000 --> 00:00:25,479
Speaker 2: an object or came to visit. They're welcome to have

7
00:00:25,520 --> 00:00:26,360
Speaker 2: dinner at my house.

8
00:00:26,480 --> 00:00:27,560
Speaker 1: What about the university?

9
00:00:27,720 --> 00:00:30,440
Speaker 2: If aliens came, I would be a superstar at the university.

10
00:00:30,480 --> 00:00:32,160
Speaker 1: Wait, you would be the star or the aliens would

11
00:00:32,159 --> 00:00:34,560
Speaker 1: be the star. I think the aliens would probably grab

12
00:00:34,600 --> 00:00:40,000
Speaker 1: the headlines more than than the receiving professor.

13
00:00:40,159 --> 00:00:43,080
Speaker 2: Yeah, probably, and we'd have lots of great questions for them.

14
00:00:43,120 --> 00:00:45,080
Speaker 1: But then, what would you feed them for dinner if

15
00:00:45,080 --> 00:00:45,920
Speaker 1: they came to your house?

16
00:00:46,280 --> 00:00:47,400
Speaker 2: Probably some engineers.

17
00:00:47,600 --> 00:00:50,839
Speaker 1: Ouch. Wait, you would do the cooking. That's pretty dark, man.

18
00:00:50,800 --> 00:00:52,320
Speaker 2: I would do a lot for alien answers.

19
00:00:52,400 --> 00:00:56,800
Speaker 1: Yeah, boy, remind me never to go visit your house.

20
00:00:58,840 --> 00:01:00,720
Speaker 2: You never know if you're coming for dinner or if

21
00:01:00,760 --> 00:01:01,680
Speaker 2: you are dinner.

22
00:01:01,840 --> 00:01:19,759
Speaker 1: Definitely not staying for dinner. Hi am Rhem, a cartoonist

23
00:01:19,800 --> 00:01:21,960
Speaker 1: and the author of Oliver's Great Big Universe.

24
00:01:22,160 --> 00:01:25,200
Speaker 2: Oh I'm Daniel. I'm a particle physicist and a professor

25
00:01:25,240 --> 00:01:27,600
Speaker 2: at UC Irvine, and I would love to get my

26
00:01:27,640 --> 00:01:31,960
Speaker 2: hands on anything alien, ideas, objects.

27
00:01:31,680 --> 00:01:34,720
Speaker 1: Visitors, anything alien that sounds little and not safe for work,

28
00:01:35,240 --> 00:01:37,880
Speaker 1: Like you would put your hands on any part of alien.

29
00:01:38,120 --> 00:01:40,200
Speaker 2: I think any part of alien would be safe for work.

30
00:01:40,240 --> 00:01:42,560
Speaker 2: You know, it's all in the interest of science.

31
00:01:42,720 --> 00:01:44,880
Speaker 1: I guess. I guess it depends on what kind of

32
00:01:44,920 --> 00:01:45,600
Speaker 1: work or you are.

33
00:01:47,440 --> 00:01:50,400
Speaker 2: If you are looking into unravel the mysteries of the cosmos,

34
00:01:50,560 --> 00:01:52,280
Speaker 2: then yeah, it's all up for grabs.

35
00:01:52,440 --> 00:01:54,160
Speaker 1: I see, you might not do like pat some bags

36
00:01:54,240 --> 00:01:57,240
Speaker 1: or something, shake some hands or tentacles perhaps.

37
00:01:57,640 --> 00:01:59,240
Speaker 2: You know, there's a lot of people on campus here

38
00:01:59,320 --> 00:02:01,760
Speaker 2: who literally get their hands a lot dirtier than I

39
00:02:01,800 --> 00:02:02,160
Speaker 2: ever do.

40
00:02:02,320 --> 00:02:05,120
Speaker 1: I'm pretty sure everybody in the world gets their hands

41
00:02:05,160 --> 00:02:09,440
Speaker 1: dirty than a physicist. I mean, I guess you do

42
00:02:09,520 --> 00:02:12,880
Speaker 1: get chalk dust on your hands kind of, or dry

43
00:02:12,880 --> 00:02:14,639
Speaker 1: eras or dust on your fingers.

44
00:02:14,760 --> 00:02:17,760
Speaker 2: We once had to unbox one thousand computers that all

45
00:02:17,840 --> 00:02:20,160
Speaker 2: arrived from Dell the same day and set them all up.

46
00:02:20,200 --> 00:02:21,560
Speaker 2: But I'm not sure what kind of dirt we got

47
00:02:21,600 --> 00:02:22,519
Speaker 2: on our hands that day.

48
00:02:23,040 --> 00:02:26,320
Speaker 1: Yeah, yeah, it doesn't sound like a working class dust there.

49
00:02:26,840 --> 00:02:29,360
Speaker 1: But anyways, welcome to our podcast. Daniel and Jorge explain

50
00:02:29,440 --> 00:02:32,320
Speaker 1: the Universe, a production of iHeartRadio, in which we.

51
00:02:32,280 --> 00:02:35,600
Speaker 2: Treat the entire universe as safe for work. We think

52
00:02:35,639 --> 00:02:39,520
Speaker 2: everything about the universe is beautiful and wonderful, nothing should

53
00:02:39,560 --> 00:02:42,760
Speaker 2: be censored, and all of its secrets should be revealed

54
00:02:42,760 --> 00:02:45,320
Speaker 2: to us. We would love to unravel them for ourselves,

55
00:02:45,360 --> 00:02:48,680
Speaker 2: but we'd also love to get some tips from aliens

56
00:02:48,720 --> 00:02:51,200
Speaker 2: about what's going on out there in deep space.

57
00:02:51,480 --> 00:02:53,839
Speaker 1: That's right. It is a beautiful universe, and we are

58
00:02:53,880 --> 00:02:55,840
Speaker 1: all visitors in it, at least for the time that

59
00:02:55,880 --> 00:02:58,560
Speaker 1: we are in this universe. So we like to give

60
00:02:58,600 --> 00:03:00,280
Speaker 1: you a little bit of a tour of what we

61
00:03:00,320 --> 00:03:02,920
Speaker 1: know and what we found out about all the cool

62
00:03:02,960 --> 00:03:05,320
Speaker 1: spots and all of the great places to see in

63
00:03:05,400 --> 00:03:06,440
Speaker 1: this great cosmos.

64
00:03:06,600 --> 00:03:08,680
Speaker 2: And most of the things we know about the cosmos

65
00:03:08,720 --> 00:03:13,200
Speaker 2: come from seeing, come from receiving photons from outer edges

66
00:03:13,320 --> 00:03:16,600
Speaker 2: of the galaxy or from other galaxies, from using that

67
00:03:16,760 --> 00:03:18,959
Speaker 2: to build a mental model in our minds of how

68
00:03:19,000 --> 00:03:22,560
Speaker 2: the universe is built. But sometimes we also get stuff

69
00:03:22,760 --> 00:03:25,280
Speaker 2: from other parts of the universe. We get tiny little

70
00:03:25,280 --> 00:03:27,880
Speaker 2: protons that might have flowed from other parts of the galaxy.

71
00:03:27,960 --> 00:03:30,960
Speaker 2: We get dust from all over. Sometimes we might even

72
00:03:31,040 --> 00:03:32,920
Speaker 2: get rocks and other stuff.

73
00:03:33,320 --> 00:03:36,240
Speaker 1: Yeah. Well, although small rocks are okay to get here

74
00:03:36,360 --> 00:03:38,680
Speaker 1: on Earth right from the deaths of space, big rocks

75
00:03:38,720 --> 00:03:39,280
Speaker 1: are a problem.

76
00:03:39,320 --> 00:03:41,080
Speaker 2: It depends a little bit on how they arrive. If

77
00:03:41,120 --> 00:03:43,520
Speaker 2: they fly by and let us study them, then that's

78
00:03:43,560 --> 00:03:46,080
Speaker 2: all right. But yeah, if they impact in the Pacific

79
00:03:46,160 --> 00:03:49,640
Speaker 2: and cause a mile high tsunami, then yes, that's a problem.

80
00:03:49,920 --> 00:03:50,200
Speaker 3: Mmmm.

81
00:03:50,760 --> 00:03:53,360
Speaker 1: You like like day visitors, not like overnight visitors.

82
00:03:55,840 --> 00:03:57,840
Speaker 2: I mean, hey, come into orbit, right, then we can

83
00:03:57,880 --> 00:03:59,400
Speaker 2: study you for years. That'd be awesome.

84
00:04:00,040 --> 00:04:01,880
Speaker 1: Is that possible? It could like a rock come and

85
00:04:02,280 --> 00:04:03,360
Speaker 1: suddenly we get a new moon.

86
00:04:03,480 --> 00:04:05,960
Speaker 2: Absolutely. As we talked about on our episode about how

87
00:04:06,000 --> 00:04:08,800
Speaker 2: moons are formed, some moons in the Solar System were

88
00:04:08,800 --> 00:04:11,960
Speaker 2: captured as they flew by. So it's certainly possible for

89
00:04:12,080 --> 00:04:15,280
Speaker 2: us to catch some weird object from another Solar system

90
00:04:15,600 --> 00:04:18,320
Speaker 2: and have it become pout of ours, an adopted planet

91
00:04:18,440 --> 00:04:18,840
Speaker 2: or moon.

92
00:04:19,040 --> 00:04:20,760
Speaker 1: Well, it's like a visitor that never leaves.

93
00:04:21,839 --> 00:04:23,000
Speaker 2: It becomes part of our family.

94
00:04:23,040 --> 00:04:25,120
Speaker 1: Man, We don't discriminate, But could it crash it into

95
00:04:25,160 --> 00:04:27,799
Speaker 1: our moon? Like, if we catch it, could it maybe

96
00:04:27,880 --> 00:04:30,720
Speaker 1: run into our current moon? That would be a problem, right.

97
00:04:30,560 --> 00:04:32,760
Speaker 2: That would be a problem. If it like disintegrated the

98
00:04:32,800 --> 00:04:34,880
Speaker 2: Moon and that to breathe and rain down on the

99
00:04:34,920 --> 00:04:37,240
Speaker 2: surface of the Earth. Yeah, you seemed to be in

100
00:04:37,279 --> 00:04:39,800
Speaker 2: kind of a cataclysmic mood today. I mean, mostly we're

101
00:04:39,839 --> 00:04:42,320
Speaker 2: just looking at this stuff and learning about the universe.

102
00:04:42,600 --> 00:04:45,240
Speaker 1: Well, you know, apparently if I go visit you, I

103
00:04:45,320 --> 00:04:47,520
Speaker 1: might end up as dinner. So I gotta, you know,

104
00:04:47,680 --> 00:04:50,240
Speaker 1: think of the worst case scenario. Apparently in this podcast,

105
00:04:50,520 --> 00:04:51,320
Speaker 1: I gotta watch out.

106
00:04:51,520 --> 00:04:53,200
Speaker 2: You do got to pay attention. That's true.

107
00:04:53,360 --> 00:04:55,800
Speaker 1: But it is a wonderful universe to visit and to

108
00:04:55,880 --> 00:05:00,200
Speaker 1: live in, and to study and to explore. And as

109
00:05:00,240 --> 00:05:03,279
Speaker 1: Daniel said, sometimes we get visitors from the far reaches

110
00:05:03,720 --> 00:05:06,880
Speaker 1: of space, and recently we got an extra special, an

111
00:05:06,960 --> 00:05:08,440
Speaker 1: extra rare kind of visitor.

112
00:05:08,600 --> 00:05:12,320
Speaker 2: That's right. In twenty seventeen, a strange rock came through

113
00:05:12,320 --> 00:05:14,600
Speaker 2: the Solar system. We called it oh Muama. It was

114
00:05:14,640 --> 00:05:18,159
Speaker 2: a big surprise to everyone and an exceptional opportunity to

115
00:05:18,279 --> 00:05:22,280
Speaker 2: learn something about the rest of the galaxy, to actually

116
00:05:22,320 --> 00:05:25,000
Speaker 2: look at a chunk from another solar system.

117
00:05:25,120 --> 00:05:28,520
Speaker 1: Wait, I feel like you're maybe prebiasing this a little bit.

118
00:05:28,560 --> 00:05:30,479
Speaker 1: How do we know it was a rock? Do we

119
00:05:30,520 --> 00:05:31,279
Speaker 1: know it was a rock?

120
00:05:31,760 --> 00:05:33,960
Speaker 2: I guess I'm not speaking technically When I say a rock,

121
00:05:34,040 --> 00:05:36,920
Speaker 2: I just mean a chunk of something, a chunk of stuff. Yes,

122
00:05:37,120 --> 00:05:38,240
Speaker 2: it was a thing, how about that?

123
00:05:39,720 --> 00:05:42,640
Speaker 1: And it has maybe one of the coolest names in astronomy,

124
00:05:42,680 --> 00:05:44,920
Speaker 1: oh Muhama. What's the origin of that name?

125
00:05:45,000 --> 00:05:48,640
Speaker 2: Daniel? That's right. It was discovered by a telescope in Hawaii,

126
00:05:48,720 --> 00:05:52,120
Speaker 2: and so they called it oh Muama, which means messenger

127
00:05:52,240 --> 00:05:54,840
Speaker 2: from Afar in one of the Hawaiian languages.

128
00:05:55,160 --> 00:06:00,279
Speaker 1: WHOA. It's like email, space email, or like space ups driver.

129
00:06:01,080 --> 00:06:04,080
Speaker 2: Does your email come in at twenty seven kilometers per second?

130
00:06:04,360 --> 00:06:06,680
Speaker 1: I think it comes a little faster than that, doesn't it? Helene?

131
00:06:06,680 --> 00:06:09,320
Speaker 1: Takes me to read it though, that's a different question.

132
00:06:09,560 --> 00:06:11,960
Speaker 2: That's right. And we talked about this object shortly after

133
00:06:12,000 --> 00:06:14,600
Speaker 2: it arrived, and all the controversy had stirred up because

134
00:06:14,800 --> 00:06:17,880
Speaker 2: there were some weird things about this object. It was

135
00:06:17,960 --> 00:06:20,440
Speaker 2: weirdly shaped, it was sort of glittering in a strange way.

136
00:06:20,480 --> 00:06:22,720
Speaker 2: It was a surprise that we even saw it. And

137
00:06:22,760 --> 00:06:25,600
Speaker 2: since then even more controversy has been stirred up.

138
00:06:25,680 --> 00:06:28,599
Speaker 1: Yeah, there's a big controversy about its origins and whether

139
00:06:28,760 --> 00:06:30,279
Speaker 1: or not it's natural.

140
00:06:30,480 --> 00:06:30,640
Speaker 2: Is it to.

141
00:06:30,880 --> 00:06:38,000
Speaker 1: On the podcast, we'll be tackling the question, was the

142
00:06:38,080 --> 00:06:42,360
Speaker 1: interstellar visitor oh muamua natural or artificial?

143
00:06:42,760 --> 00:06:47,360
Speaker 4: Band And by artificial we mean alien. Oh I thought

144
00:06:47,360 --> 00:06:52,960
Speaker 4: you just meant like not organic, like not good to eat. Yeah,

145
00:06:53,000 --> 00:06:54,880
Speaker 4: like it has esper tame or something.

146
00:06:54,960 --> 00:06:57,040
Speaker 2: Yeah, you got to cut down on your artificial space

147
00:06:57,160 --> 00:06:58,760
Speaker 2: junk man. It's not good for your diet.

148
00:06:59,360 --> 00:06:59,600
Speaker 5: Yeah.

149
00:06:59,680 --> 00:07:02,920
Speaker 2: Yeah, come to my house. We serve you purely organic engineers.

150
00:07:03,120 --> 00:07:09,640
Speaker 1: Oh my goodness, your house again. You seem to be

151
00:07:09,680 --> 00:07:10,960
Speaker 1: making that joke a little too much.

152
00:07:11,840 --> 00:07:14,440
Speaker 2: But this is a really fun question because getting a

153
00:07:14,520 --> 00:07:17,080
Speaker 2: chunk of stuff from another Solar system is a way

154
00:07:17,120 --> 00:07:19,080
Speaker 2: to see what's out there. Right, It's like a core

155
00:07:19,160 --> 00:07:21,760
Speaker 2: sample of the rest of the universe, something we very

156
00:07:21,880 --> 00:07:24,280
Speaker 2: rarely get to see because we're on this little island

157
00:07:24,320 --> 00:07:26,280
Speaker 2: of the Solar System, this little patch of land that

158
00:07:26,320 --> 00:07:28,200
Speaker 2: we've been able to explore with our probes.

159
00:07:28,360 --> 00:07:31,280
Speaker 1: Well, it might be a core sample of perhaps alien

160
00:07:31,400 --> 00:07:32,320
Speaker 1: technology or something.

161
00:07:32,400 --> 00:07:32,520
Speaker 3: Right.

162
00:07:32,560 --> 00:07:35,280
Speaker 1: That is the big question about OHM. Was it natural?

163
00:07:35,400 --> 00:07:37,880
Speaker 1: Is it like just a rock that's naturally floating out

164
00:07:37,880 --> 00:07:40,680
Speaker 1: there in space, or could it be some sort of

165
00:07:40,840 --> 00:07:45,280
Speaker 1: device or spaceship or something made by an alien civilization.

166
00:07:45,000 --> 00:07:47,400
Speaker 2: That's the big question. And when this thing came to

167
00:07:47,480 --> 00:07:50,240
Speaker 2: the Solar system, a bunch of astronomers looked at it

168
00:07:50,280 --> 00:07:52,840
Speaker 2: and studied it and debated it, of course, and one

169
00:07:52,880 --> 00:07:55,600
Speaker 2: astronomer in particular has made a lot of hay about it,

170
00:07:55,640 --> 00:07:58,600
Speaker 2: Avi Lob But professor at Harvard wrote a book called

171
00:07:58,720 --> 00:08:03,360
Speaker 2: Extraterrestrial The First Sign of Intelligent Life whoa This of

172
00:08:03,360 --> 00:08:06,400
Speaker 2: course made a big splash and was a best seller

173
00:08:06,720 --> 00:08:08,720
Speaker 2: and got a lot of people talking. The sort of

174
00:08:08,760 --> 00:08:12,120
Speaker 2: mainstream community in astronomer didn't take it very seriously, and

175
00:08:12,200 --> 00:08:15,280
Speaker 2: Professor Loepe has complained somewhat that his arguments have not

176
00:08:15,360 --> 00:08:17,760
Speaker 2: been addressed by sort of mainstream astronomy.

177
00:08:17,960 --> 00:08:20,840
Speaker 1: You mean, he claimed that the omuma was a sign

178
00:08:20,960 --> 00:08:24,160
Speaker 1: that there are aliens out there, and now he's saying

179
00:08:24,160 --> 00:08:25,880
Speaker 1: that the people aren't taking him seriously.

180
00:08:25,960 --> 00:08:27,080
Speaker 2: Yeah, that's exactly right.

181
00:08:27,160 --> 00:08:28,760
Speaker 1: Well, as usual, we were wondering how many of our

182
00:08:28,800 --> 00:08:31,760
Speaker 1: listeners out there had heard of Omuama and had thought

183
00:08:31,800 --> 00:08:34,000
Speaker 1: about whether it was natural or artificial.

184
00:08:34,200 --> 00:08:36,800
Speaker 2: So I'm actually visiting UC Riverside this week, so I

185
00:08:36,800 --> 00:08:39,080
Speaker 2: took the opportunity to walk around campus here at Usey

186
00:08:39,200 --> 00:08:41,920
Speaker 2: Riverside and ask people if they had heard of omuamua

187
00:08:42,120 --> 00:08:44,840
Speaker 2: and if they thought it was natural or artificial.

188
00:08:45,080 --> 00:08:46,840
Speaker 1: So think about it for a second. Have you heard

189
00:08:46,920 --> 00:08:50,160
Speaker 1: of omuama before? And do you think it could be

190
00:08:50,400 --> 00:08:53,320
Speaker 1: a sign of aliens? Here's what people had to say.

191
00:08:53,520 --> 00:08:56,760
Speaker 2: All right, So do you think omuamua was natural or artificial?

192
00:08:57,559 --> 00:08:58,040
Speaker 3: Natural?

193
00:08:58,320 --> 00:09:02,080
Speaker 2: Why is that? Have you heard of the object, oh,

194
00:09:02,160 --> 00:09:05,920
Speaker 2: Mua mua, the interstellar commet They came through the solar

195
00:09:05,920 --> 00:09:06,839
Speaker 2: system five years ago?

196
00:09:07,400 --> 00:09:07,439
Speaker 3: No?

197
00:09:07,720 --> 00:09:09,800
Speaker 2: No, okay? Great? Do you have an opinion about whether

198
00:09:09,880 --> 00:09:12,319
Speaker 2: it was a natural object like a comment from another

199
00:09:12,320 --> 00:09:15,959
Speaker 2: solar system or an artificial object like an alien craft?

200
00:09:16,760 --> 00:09:17,480
Speaker 1: Maybe natural?

201
00:09:17,840 --> 00:09:18,080
Speaker 2: Maybe?

202
00:09:18,120 --> 00:09:18,400
Speaker 3: Natural?

203
00:09:18,520 --> 00:09:23,040
Speaker 2: Okay, great? I never heard about it, this object that

204
00:09:23,040 --> 00:09:26,760
Speaker 2: came through Russell Solar System. All right, great? Do you

205
00:09:26,760 --> 00:09:29,560
Speaker 2: think it's more likely to be a natural object or

206
00:09:29,760 --> 00:09:30,920
Speaker 2: alien space junk?

207
00:09:33,440 --> 00:09:34,880
Speaker 5: More like a natural object?

208
00:09:35,040 --> 00:09:37,840
Speaker 2: Natural object? Because there's no evidence now.

209
00:09:37,800 --> 00:09:41,280
Speaker 1: We found an alien right right, so.

210
00:09:41,320 --> 00:09:42,840
Speaker 5: It's more like a natural object.

211
00:09:43,440 --> 00:09:44,440
Speaker 2: How did you do an opinion?

212
00:09:45,040 --> 00:09:45,280
Speaker 5: Yeah?

213
00:09:45,320 --> 00:09:47,360
Speaker 1: More or less the same natural objects.

214
00:09:47,080 --> 00:09:50,199
Speaker 3: It was more likely absolutely natural objects.

215
00:09:51,400 --> 00:09:52,679
Speaker 1: All right. First of all, I'm not a lot of

216
00:09:52,720 --> 00:09:55,439
Speaker 1: name recognition, it seems, at least not in Riverside.

217
00:09:55,600 --> 00:09:58,079
Speaker 2: I was even walking around the physics department at the

218
00:09:58,160 --> 00:10:00,840
Speaker 2: Riverside hoping to get people who thought about this stuff.

219
00:10:01,320 --> 00:10:04,280
Speaker 1: Maybe you weren't pronouncing it right, Probably not.

220
00:10:04,559 --> 00:10:05,640
Speaker 2: Yeah, you were.

221
00:10:05,520 --> 00:10:08,160
Speaker 1: Attaching it to a dinner invitation, which is a problem

222
00:10:08,200 --> 00:10:09,120
Speaker 1: now that you have a reputation.

223
00:10:10,280 --> 00:10:12,640
Speaker 2: I'm standing away from the engineering buildings on every campus

224
00:10:12,640 --> 00:10:13,080
Speaker 2: from now on.

225
00:10:13,200 --> 00:10:15,240
Speaker 1: Yeah, it sounds like the engeneers just stay away from you.

226
00:10:16,000 --> 00:10:18,600
Speaker 1: But yeah, a not a lot of recognition. Although some

227
00:10:18,600 --> 00:10:21,000
Speaker 1: people had heard of it and they seem to think

228
00:10:21,040 --> 00:10:21,600
Speaker 1: it's natural.

229
00:10:21,679 --> 00:10:23,400
Speaker 2: They do seem to think it's natural. I mean, it's

230
00:10:23,400 --> 00:10:26,040
Speaker 2: a fascinating object and there are some things about it

231
00:10:26,040 --> 00:10:29,040
Speaker 2: that are weird that can teach us about what's out

232
00:10:29,040 --> 00:10:31,200
Speaker 2: there in the universe. I think the evidence for it

233
00:10:31,240 --> 00:10:34,439
Speaker 2: being actually alien is quite a reach. That kind of

234
00:10:34,480 --> 00:10:36,480
Speaker 2: thing you might put in a best selling book that

235
00:10:36,520 --> 00:10:38,000
Speaker 2: you want to sell a lot of copies of, but

236
00:10:38,120 --> 00:10:40,240
Speaker 2: not something that would really stand up to peer review.

237
00:10:40,880 --> 00:10:41,320
Speaker 2: I see.

238
00:10:41,360 --> 00:10:44,080
Speaker 1: I mean, if a physics professor writes a book about aliens,

239
00:10:44,160 --> 00:10:47,680
Speaker 1: that's obviously just a big money grab, right.

240
00:10:49,240 --> 00:10:50,920
Speaker 2: I think it depends on the claims you put in

241
00:10:50,960 --> 00:10:53,520
Speaker 2: that book. And so on the episode today, we wanted

242
00:10:53,520 --> 00:10:56,960
Speaker 2: to dig deep into what's going on with Omua Mua.

243
00:10:57,400 --> 00:10:59,560
Speaker 2: Is it natural? Is it artificial? What do we know

244
00:10:59,600 --> 00:11:01,080
Speaker 2: about it? What can we say?

245
00:11:01,360 --> 00:11:03,720
Speaker 1: Well, let's dig into it, then, Daniel, what is this

246
00:11:03,840 --> 00:11:05,640
Speaker 1: object and when was it first spotted?

247
00:11:05,800 --> 00:11:08,600
Speaker 2: So it's definitely from another solar system. We spotted it

248
00:11:08,640 --> 00:11:13,920
Speaker 2: first on October eighteenth, twenty seventeen by the pan Star's telescope.

249
00:11:14,280 --> 00:11:16,800
Speaker 2: This is a really awesome telescope. It's in Hawaii. It's

250
00:11:16,800 --> 00:11:19,000
Speaker 2: actually two of them. Each of them are almost two

251
00:11:19,120 --> 00:11:21,880
Speaker 2: meters in diameter, and they're on the summit of Haleyakela

252
00:11:22,200 --> 00:11:25,160
Speaker 2: on the island of Maui, and their job is basically

253
00:11:25,240 --> 00:11:28,040
Speaker 2: to look for stuff that might hit the Earth. They're

254
00:11:28,080 --> 00:11:30,679
Speaker 2: taking pictures of the night sky all the time and

255
00:11:30,720 --> 00:11:33,559
Speaker 2: they're looking for changes, looking for stuff that's moving. It's

256
00:11:33,600 --> 00:11:36,240
Speaker 2: part of this search for Near Earth objects to see

257
00:11:36,240 --> 00:11:38,000
Speaker 2: whether there are things out there that are moving that

258
00:11:38,120 --> 00:11:39,520
Speaker 2: might of course hit the Earth.

259
00:11:39,800 --> 00:11:42,400
Speaker 1: Well, it's pretty cool. It's like a WatchGuard almost for

260
00:11:42,440 --> 00:11:44,920
Speaker 1: the entire planet. It's a full time it's doing that

261
00:11:44,960 --> 00:11:45,480
Speaker 1: full time.

262
00:11:45,559 --> 00:11:48,200
Speaker 2: It's doing that full time. It's pretty awesome. This is

263
00:11:48,240 --> 00:11:50,480
Speaker 2: sort of a newer effort by NASK. It really was

264
00:11:50,559 --> 00:11:53,280
Speaker 2: kicked off after comet shoemaker Levy in the nineties when

265
00:11:53,280 --> 00:11:55,800
Speaker 2: we saw, wow, things in the Solar system really can

266
00:11:55,960 --> 00:11:58,959
Speaker 2: impact comments and cause huge fireballs. We got to put

267
00:11:59,000 --> 00:12:01,000
Speaker 2: some more money on this. So in the last twenty

268
00:12:01,120 --> 00:12:03,920
Speaker 2: or thirty years, NASA and some international partners have really

269
00:12:03,920 --> 00:12:07,360
Speaker 2: dedicated some resources to looking for near Earth objects. And

270
00:12:07,480 --> 00:12:09,480
Speaker 2: they see a lot of them, and they've cataloged all

271
00:12:09,520 --> 00:12:12,120
Speaker 2: the big ones, and we know mostly what's out there,

272
00:12:12,280 --> 00:12:15,600
Speaker 2: but sometimes they see something strange. And in twenty seventeen

273
00:12:15,640 --> 00:12:17,800
Speaker 2: they saw this object moving in a way that they

274
00:12:17,800 --> 00:12:20,679
Speaker 2: could tell it was not coming from inside of our

275
00:12:20,720 --> 00:12:21,360
Speaker 2: Solar system.

276
00:12:21,480 --> 00:12:24,480
Speaker 1: Interesting, so just out there looking at this night sky

277
00:12:24,559 --> 00:12:27,719
Speaker 1: all the time and it records if something changes. Now,

278
00:12:27,720 --> 00:12:30,920
Speaker 1: how did they know that it was coming from outside

279
00:12:30,920 --> 00:12:31,559
Speaker 1: the Solar.

280
00:12:31,280 --> 00:12:33,280
Speaker 2: System because of where he was coming from. It entered

281
00:12:33,280 --> 00:12:35,440
Speaker 2: from above the plane of the Solar system. The whole

282
00:12:35,440 --> 00:12:38,680
Speaker 2: Solar system is basically flat. Everything's orbiting in a plane

283
00:12:38,760 --> 00:12:41,360
Speaker 2: that's determined by the north south pole of the Sun.

284
00:12:41,480 --> 00:12:43,760
Speaker 2: But this thing was sort of coming in from above

285
00:12:43,800 --> 00:12:46,360
Speaker 2: the plane from the direction of the constellation Lira, and

286
00:12:46,480 --> 00:12:49,160
Speaker 2: passed really close to the Sun, actually within the orbit

287
00:12:49,200 --> 00:12:51,280
Speaker 2: of Mercury, and then out the other side.

288
00:12:51,440 --> 00:12:53,280
Speaker 1: I guess the question is, you know, if you look

289
00:12:53,280 --> 00:12:55,000
Speaker 1: at the night sky and you see a streak, it's

290
00:12:55,040 --> 00:12:57,160
Speaker 1: kind of hard to tell in three D where it

291
00:12:57,240 --> 00:13:00,880
Speaker 1: is or where it's going, or you know exactly what direction,

292
00:13:01,040 --> 00:13:03,240
Speaker 1: just because you're getting just to the view of it.

293
00:13:03,480 --> 00:13:05,560
Speaker 1: How did they figure out where in the Solar system

294
00:13:05,640 --> 00:13:06,120
Speaker 1: it was going?

295
00:13:06,240 --> 00:13:08,360
Speaker 2: You can reconstruct its three D trajectory. First of all,

296
00:13:08,360 --> 00:13:10,080
Speaker 2: we have two of these cameras who have a slightly

297
00:13:10,120 --> 00:13:13,040
Speaker 2: binocular view. But then also as it gets brighter and dimmer,

298
00:13:13,080 --> 00:13:15,280
Speaker 2: you can figure out sort of its radial velocity, and

299
00:13:15,280 --> 00:13:17,840
Speaker 2: they can measure its velocity across our view just by

300
00:13:17,840 --> 00:13:19,720
Speaker 2: seeing how the points of light are moving, So they

301
00:13:19,760 --> 00:13:21,719
Speaker 2: can end up with a three D trajectory and then

302
00:13:21,760 --> 00:13:24,440
Speaker 2: backtrack and say where could this thing have come from

303
00:13:24,440 --> 00:13:25,760
Speaker 2: in order to give us this path?

304
00:13:26,280 --> 00:13:28,120
Speaker 1: Now, I think you said that they saw a streak,

305
00:13:28,600 --> 00:13:30,720
Speaker 1: not just a little point flying through space.

306
00:13:30,840 --> 00:13:32,959
Speaker 2: Yeah, most of the stuff in the Solar system is moving,

307
00:13:33,040 --> 00:13:35,320
Speaker 2: and it's moving fast, but it's not moving that fast.

308
00:13:35,480 --> 00:13:38,000
Speaker 2: So on this camera it usually just registers as a

309
00:13:38,040 --> 00:13:40,839
Speaker 2: pixel like light from the Sun hits it bounces off

310
00:13:40,840 --> 00:13:43,520
Speaker 2: and it comes into the telescope in Hawaii and it

311
00:13:43,559 --> 00:13:45,880
Speaker 2: makes a bright pixel and we say, okay, there's something there.

312
00:13:46,080 --> 00:13:49,160
Speaker 2: But this was moving so fast twenty six kilometers per

313
00:13:49,200 --> 00:13:52,520
Speaker 2: second relative to our solar system that actually made a streak.

314
00:13:52,559 --> 00:13:55,720
Speaker 2: It was like multiple pixels across whoa.

315
00:13:55,240 --> 00:13:57,600
Speaker 1: And so, and I guess they didn't just see it once.

316
00:13:57,640 --> 00:13:59,199
Speaker 1: They could track this thing, right.

317
00:13:59,040 --> 00:14:00,960
Speaker 2: They could track this thing exactly, But by the time

318
00:14:01,000 --> 00:14:03,200
Speaker 2: they saw it, it was already on its way out

319
00:14:03,280 --> 00:14:05,520
Speaker 2: of the Solar system. Like it made its closest approach

320
00:14:05,559 --> 00:14:07,920
Speaker 2: to the Sun and then came closer and closer to

321
00:14:07,920 --> 00:14:09,760
Speaker 2: the Earth, And by the time we saw it on

322
00:14:09,760 --> 00:14:11,520
Speaker 2: the Earth, it was already sort of like on its

323
00:14:11,520 --> 00:14:13,559
Speaker 2: way out of the Solar system. So then we could

324
00:14:13,600 --> 00:14:15,959
Speaker 2: just sort of like watch it from behind as it left,

325
00:14:16,160 --> 00:14:18,280
Speaker 2: and then it got dimmer and dimmer and dimmer. So

326
00:14:18,320 --> 00:14:20,440
Speaker 2: we only had a few weeks to gather data about

327
00:14:20,440 --> 00:14:22,760
Speaker 2: this thing. Whoa wa, wait, wait, why didn't we see

328
00:14:22,760 --> 00:14:24,600
Speaker 2: it before we saw it when it came close to

329
00:14:24,640 --> 00:14:27,120
Speaker 2: the Earth, And that's the easiest time to see it.

330
00:14:27,200 --> 00:14:29,360
Speaker 2: Before that, it was either like coming from the Sun,

331
00:14:29,400 --> 00:14:31,840
Speaker 2: which makes it impossible to see it, or it was

332
00:14:31,880 --> 00:14:32,400
Speaker 2: too dark.

333
00:14:32,600 --> 00:14:34,680
Speaker 1: The object itself was too dark because I guess it

334
00:14:34,720 --> 00:14:37,960
Speaker 1: wasn't glowing by itself. It was just reflecting light exactly.

335
00:14:38,080 --> 00:14:39,920
Speaker 2: You need to be sort of lucky with the arrangement

336
00:14:40,000 --> 00:14:41,840
Speaker 2: of the Sun and the object and the Earth to

337
00:14:41,960 --> 00:14:44,120
Speaker 2: even see these things, right, because you need light from

338
00:14:44,160 --> 00:14:46,360
Speaker 2: the Sun to hit it and then bounce off and

339
00:14:46,480 --> 00:14:48,400
Speaker 2: hit the Earth. As you say, it's not glowing. It

340
00:14:48,440 --> 00:14:50,880
Speaker 2: doesn't have fusion. It's just a big chunk of stuff.

341
00:14:50,880 --> 00:14:53,200
Speaker 2: It has to reflect light to us from the Sun

342
00:14:53,320 --> 00:14:56,080
Speaker 2: and lots of spots on its trajectory to be basically invisible.

343
00:14:56,160 --> 00:14:58,480
Speaker 1: Well, scientists noticed some weird things about it that make

344
00:14:58,560 --> 00:15:02,080
Speaker 1: them think that, hmm, if this thing is natural or

345
00:15:02,120 --> 00:15:04,680
Speaker 1: of alien origin. So let's stick into what those odd

346
00:15:04,680 --> 00:15:07,080
Speaker 1: things about it were and talk about whether it is

347
00:15:07,200 --> 00:15:09,880
Speaker 1: a message from aliens. But first let's take a quick break,

348
00:15:22,920 --> 00:15:25,840
Speaker 1: all right, we're talking about visitors to our solar system.

349
00:15:26,120 --> 00:15:30,000
Speaker 1: In twenty seventeen, we got one that we seemed a

350
00:15:30,040 --> 00:15:31,000
Speaker 1: little fishy.

351
00:15:31,480 --> 00:15:34,200
Speaker 2: Called it definitely was a lot of fun to look

352
00:15:34,240 --> 00:15:35,520
Speaker 2: at and to think about, all right.

353
00:15:35,560 --> 00:15:39,080
Speaker 1: So we saw this in our telescopes looking for asteroids

354
00:15:39,120 --> 00:15:41,480
Speaker 1: out there in space, and there was something a little

355
00:15:41,520 --> 00:15:44,360
Speaker 1: bit different about its trajectory seemed to be coming definitely

356
00:15:44,360 --> 00:15:47,640
Speaker 1: from outside the Solar system, and scientists think at least

357
00:15:47,640 --> 00:15:50,920
Speaker 1: the time they thought or are they considered the possibility

358
00:15:51,200 --> 00:15:54,720
Speaker 1: that it might be from an alien civilization or something.

359
00:15:54,800 --> 00:15:56,600
Speaker 1: What were some of the things that made people think, hmm,

360
00:15:56,720 --> 00:15:58,520
Speaker 1: this isn't maybe just an asteroid.

361
00:15:58,760 --> 00:16:00,800
Speaker 2: So first of all, it seemed to have a weird shape,

362
00:16:01,280 --> 00:16:03,200
Speaker 2: like a lot of the asteroids in our solar system

363
00:16:03,240 --> 00:16:06,880
Speaker 2: are mostly spherical, like they're round ish. This thing either

364
00:16:07,040 --> 00:16:09,360
Speaker 2: was really really long and thin. A lot of the

365
00:16:09,440 --> 00:16:11,960
Speaker 2: artistic depictions of it draw it sort of like a cigar,

366
00:16:12,520 --> 00:16:14,560
Speaker 2: or it was sort of flat, like a pancake. So

367
00:16:14,560 --> 00:16:16,680
Speaker 2: that's thing number one that makes it kind of weird.

368
00:16:16,800 --> 00:16:19,440
Speaker 1: But could we actually see its shape or isn't it

369
00:16:19,520 --> 00:16:21,560
Speaker 1: so far away? Could you basically just see a dot?

370
00:16:21,680 --> 00:16:24,120
Speaker 2: Yeah, we can't see its shape directly, you're right, but

371
00:16:24,160 --> 00:16:26,400
Speaker 2: we could deduce its shape by how it's spinning and

372
00:16:26,440 --> 00:16:29,680
Speaker 2: how its brightness changes. So it's not a sphere. Then

373
00:16:29,760 --> 00:16:32,760
Speaker 2: as it spins, you might reflect more or less light

374
00:16:32,800 --> 00:16:35,760
Speaker 2: off the larger or smaller surfaces that it's presenting, So

375
00:16:35,760 --> 00:16:38,440
Speaker 2: they have to deduce its shape from how it's spinning,

376
00:16:38,440 --> 00:16:40,600
Speaker 2: which is why we're not sure if it's a cigar

377
00:16:40,760 --> 00:16:43,560
Speaker 2: or a pancake. We just know it's not very spherical.

378
00:16:43,680 --> 00:16:46,040
Speaker 1: Wait, so if it was spherical, then we just looked

379
00:16:46,080 --> 00:16:49,120
Speaker 1: like a constant dot of light in the sky, right.

380
00:16:49,360 --> 00:16:51,120
Speaker 1: But this wasn't a constant dot of light.

381
00:16:51,240 --> 00:16:53,680
Speaker 2: It was not a constant dot of light. Exactly what

382
00:16:53,840 --> 00:16:56,840
Speaker 2: was it? The light varied really dramatically, like by factors

383
00:16:56,880 --> 00:16:59,440
Speaker 2: of ten, so which made them think that maybe it

384
00:16:59,480 --> 00:17:01,600
Speaker 2: was really long and thin, and sometimes you were seeing

385
00:17:01,640 --> 00:17:03,400
Speaker 2: the long side of it, and sometimes it was really

386
00:17:03,520 --> 00:17:05,640
Speaker 2: narrow and you were just reflecting light off the tip.

387
00:17:05,720 --> 00:17:08,840
Speaker 2: But definitely was not a sphere because otherwise, as you say,

388
00:17:09,040 --> 00:17:10,560
Speaker 2: it would give you a constant signal.

389
00:17:10,720 --> 00:17:13,000
Speaker 1: So it was like blinking or just kind of fading

390
00:17:13,000 --> 00:17:13,440
Speaker 1: in and out.

391
00:17:13,520 --> 00:17:15,960
Speaker 2: It was more fading in and out, never totally disappear.

392
00:17:16,080 --> 00:17:17,719
Speaker 2: If you look at the light curve, you see it

393
00:17:17,800 --> 00:17:19,960
Speaker 2: varies over a very wide range.

394
00:17:19,760 --> 00:17:23,040
Speaker 1: In what timescale, like every hour, every second.

395
00:17:22,840 --> 00:17:25,200
Speaker 2: More like hours exactly. We only have a few weeks

396
00:17:25,240 --> 00:17:27,480
Speaker 2: of data of this thing. But it was spinning pretty fast.

397
00:17:27,680 --> 00:17:30,359
Speaker 2: I think it was also tumbling, like it wasn't only

398
00:17:30,400 --> 00:17:32,960
Speaker 2: spinning along one axis, it was like spinning in two

399
00:17:33,040 --> 00:17:34,440
Speaker 2: different ways at the same time.

400
00:17:34,600 --> 00:17:36,600
Speaker 1: But at least we think it was spinning, right, We

401
00:17:36,640 --> 00:17:39,640
Speaker 1: don't actually know because you just see a pixel of light, right.

402
00:17:39,720 --> 00:17:42,480
Speaker 2: Yeah, exactly, this is all reconstruction. But there was a

403
00:17:42,480 --> 00:17:44,760
Speaker 2: bunch of stuff about it which seemed kind of weird.

404
00:17:44,840 --> 00:17:47,359
Speaker 2: There was the shape that was how it moved. It

405
00:17:47,440 --> 00:17:50,160
Speaker 2: seemed to move in a way that wasn't just gravity.

406
00:17:50,560 --> 00:17:52,359
Speaker 2: Seemed like it got a little boost as it was

407
00:17:52,440 --> 00:17:54,560
Speaker 2: leaving the Solar System, which made people think like, ooh,

408
00:17:54,600 --> 00:17:57,600
Speaker 2: maybe it's an alien spaceship, or maybe it's a light

409
00:17:57,720 --> 00:18:00,520
Speaker 2: sale or these things that like gathers folk tons from

410
00:18:00,560 --> 00:18:03,800
Speaker 2: stars to pick up acceleration. So that was Avi Lobe's

411
00:18:03,800 --> 00:18:07,639
Speaker 2: suggestion that this might be a discarded alien light sale

412
00:18:07,840 --> 00:18:10,080
Speaker 2: that fell through our Solar system.

413
00:18:10,080 --> 00:18:13,040
Speaker 1: And it's also kind of rare to get stuff from

414
00:18:13,040 --> 00:18:15,439
Speaker 1: that direction, right, like we don't get a lot of

415
00:18:15,440 --> 00:18:18,240
Speaker 1: comments or asteroids from our asteroid build.

416
00:18:18,359 --> 00:18:20,199
Speaker 2: Well, we don't know how rare it is, right. We

417
00:18:20,280 --> 00:18:23,560
Speaker 2: sort of turned on this eyeball to the universe fairly recently,

418
00:18:23,720 --> 00:18:26,960
Speaker 2: and seeing one sort of new either means that we're very,

419
00:18:27,040 --> 00:18:29,160
Speaker 2: very lucky, or it means that there may be more

420
00:18:29,240 --> 00:18:32,919
Speaker 2: common than initial calculations suggest it could be that space

421
00:18:33,040 --> 00:18:37,040
Speaker 2: is filled with chunks little bits from other solar systems,

422
00:18:37,080 --> 00:18:38,880
Speaker 2: and it's not that unusual to see one.

423
00:18:38,960 --> 00:18:40,800
Speaker 1: All right. There were some weird things about it that

424
00:18:40,880 --> 00:18:44,600
Speaker 1: made people wonder about this, but one professor in particular

425
00:18:44,760 --> 00:18:46,800
Speaker 1: sort of seemed to have gone all in on it.

426
00:18:46,840 --> 00:18:49,800
Speaker 2: That's right. Jason Wright, a professor at Penn State, wrote

427
00:18:49,880 --> 00:18:53,320
Speaker 2: a detailed blog post responding point by point to all

428
00:18:53,320 --> 00:18:56,040
Speaker 2: the claims made in Avi Lobe's book. And I thought

429
00:18:56,080 --> 00:18:57,680
Speaker 2: it would be a good idea to chat with him

430
00:18:58,000 --> 00:19:01,040
Speaker 2: about all these ideas and what he thought Omama might

431
00:19:01,119 --> 00:19:01,840
Speaker 2: actually have been.

432
00:19:02,040 --> 00:19:04,280
Speaker 1: Okay, So then, just to be clear, you spoke to

433
00:19:04,560 --> 00:19:08,280
Speaker 1: Jason Wright, who's arguing against the book written by Lobe,

434
00:19:08,840 --> 00:19:12,520
Speaker 1: who argued that om Oma was of not just extra

435
00:19:12,640 --> 00:19:15,200
Speaker 1: terrestrial origin, which it is because it's not from Earth,

436
00:19:15,600 --> 00:19:17,679
Speaker 1: but that it's a sign of intelligent life.

437
00:19:17,840 --> 00:19:21,080
Speaker 2: Yeah, that's right. Loeb is making some pretty outlandish claims

438
00:19:21,080 --> 00:19:23,400
Speaker 2: in his book, and he's also complaining that nobody's taking

439
00:19:23,480 --> 00:19:26,240
Speaker 2: him seriously. So Jason Wright decided to take it seriously

440
00:19:26,560 --> 00:19:28,879
Speaker 2: and address all the claims and say what we know

441
00:19:29,080 --> 00:19:31,040
Speaker 2: and what we don't know. And of course nobody knows

442
00:19:31,080 --> 00:19:32,760
Speaker 2: for sure what this thing was, but we should be

443
00:19:32,800 --> 00:19:34,120
Speaker 2: careful about the claims we make.

444
00:19:34,240 --> 00:19:37,040
Speaker 1: All right, Well, here's Daniel's interview with Professor Jason Wright.

445
00:19:39,359 --> 00:19:41,719
Speaker 2: Great so that it's my pleasure to introduce to the

446
00:19:41,720 --> 00:19:46,760
Speaker 2: podcast Professor Jason Wright. He's professor of astronomy and astrophysics

447
00:19:46,760 --> 00:19:49,320
Speaker 2: at Penn State. He's a member of the Center for

448
00:19:49,400 --> 00:19:53,080
Speaker 2: Exo Planet's and Habitable Worlds, and amazingly, he's the director

449
00:19:53,119 --> 00:19:58,000
Speaker 2: of the Penn State Extraterrestrial Intelligence Center, which sounds like

450
00:19:58,040 --> 00:19:59,960
Speaker 2: a lot of fun. Jason, Welcome to the podcast.

451
00:20:00,200 --> 00:20:01,160
Speaker 5: Thanks good to be here.

452
00:20:01,320 --> 00:20:04,360
Speaker 2: As director of the Extraterrestrial Intelligence Center, do you get

453
00:20:04,400 --> 00:20:07,080
Speaker 2: first access to the alien bodies to interrogate them and

454
00:20:07,119 --> 00:20:07,960
Speaker 2: ask them questions?

455
00:20:08,240 --> 00:20:12,200
Speaker 3: No, no, thank goodness. That's that's definitely outside the purview

456
00:20:12,280 --> 00:20:14,399
Speaker 3: of what we do here at the Pace SETI Center.

457
00:20:14,560 --> 00:20:17,240
Speaker 3: So yeah, I can't have no information on that.

458
00:20:17,240 --> 00:20:17,800
Speaker 5: Score for you.

459
00:20:18,800 --> 00:20:20,399
Speaker 2: All right, Well, I do want to ask you questions

460
00:20:20,400 --> 00:20:22,560
Speaker 2: about things you're actually an expert in, and I was

461
00:20:22,640 --> 00:20:24,840
Speaker 2: very excited to talk to you because this blog post

462
00:20:24,840 --> 00:20:27,360
Speaker 2: you wrote where you did a point by point analysis

463
00:20:27,400 --> 00:20:31,760
Speaker 2: of the claims made in Avulobe's book about the possible

464
00:20:31,800 --> 00:20:35,439
Speaker 2: extraterrestrial or alien nature of O Muamua. So I'd love

465
00:20:35,440 --> 00:20:37,920
Speaker 2: to ask you first to briefly run down what are

466
00:20:37,960 --> 00:20:40,120
Speaker 2: the evidence for the anomalies what a sort of five

467
00:20:40,200 --> 00:20:43,520
Speaker 2: categories he lays out, and then dig into them with you.

468
00:20:43,840 --> 00:20:47,439
Speaker 3: Yeah, so, Omuma, you know, it was definitely interstellar, We

469
00:20:47,520 --> 00:20:51,520
Speaker 3: know that for sure, and it was definitely very strange.

470
00:20:51,880 --> 00:20:53,760
Speaker 3: But when we say it's strange, what we mean is

471
00:20:53,760 --> 00:20:56,400
Speaker 3: we kind of had a sense for roughly what comments

472
00:20:56,400 --> 00:20:58,280
Speaker 3: look like in general, and we thought when we saw

473
00:20:58,320 --> 00:21:01,120
Speaker 3: one come from interstellar space, it would more or less

474
00:21:01,160 --> 00:21:04,080
Speaker 3: look like the comets that orbit the Sun. And the

475
00:21:04,119 --> 00:21:06,320
Speaker 3: main reason is that the comets that orbit the Sun,

476
00:21:06,359 --> 00:21:09,160
Speaker 3: that come from the Ork Cloud very far out, they're

477
00:21:09,200 --> 00:21:12,840
Speaker 3: basically in interstellar space. There's not a big difference between

478
00:21:12,840 --> 00:21:14,840
Speaker 3: the space and the Ork Cloud and between the stars,

479
00:21:14,960 --> 00:21:17,480
Speaker 3: and so we didn't expect it to be so different

480
00:21:17,480 --> 00:21:18,520
Speaker 3: from typical comets.

481
00:21:19,040 --> 00:21:19,760
Speaker 5: There's a big.

482
00:21:19,600 --> 00:21:22,399
Speaker 3: Caveat with that, though, which is that O Muhamuha was

483
00:21:22,440 --> 00:21:27,919
Speaker 3: extremely small, and we don't generally detect comets that's small

484
00:21:28,200 --> 00:21:31,320
Speaker 3: in the Solar System just because being so small, they

485
00:21:31,320 --> 00:21:33,919
Speaker 3: reflect hardly any light and they're very hard to see.

486
00:21:34,080 --> 00:21:36,760
Speaker 3: We have very few examples of any objects in the

487
00:21:36,760 --> 00:21:39,919
Speaker 3: Solar System that small orbiting the Sun, which means we

488
00:21:39,920 --> 00:21:43,440
Speaker 3: don't actually have a basis to compare to. So when

489
00:21:43,440 --> 00:21:46,080
Speaker 3: we say it's strange, it's really strange compared to expectations,

490
00:21:46,440 --> 00:21:50,080
Speaker 3: not necessarily strange with respect to ordinary comets in the

491
00:21:50,080 --> 00:21:54,119
Speaker 3: Solar System of that size. So the first thing that

492
00:21:54,240 --> 00:21:57,480
Speaker 3: was really strange about it is that its brightness varied

493
00:21:58,280 --> 00:22:02,600
Speaker 3: a lot, and that has been interpreted to mean that

494
00:22:02,680 --> 00:22:06,199
Speaker 3: it must not be round, which is perfectly reasonable for

495
00:22:06,240 --> 00:22:08,720
Speaker 3: something of that size. You have to be quite large,

496
00:22:08,760 --> 00:22:10,600
Speaker 3: like a large asteroid, to be round. But it was

497
00:22:10,640 --> 00:22:15,120
Speaker 3: really extreme. I mean, the brightness variations indicated that the

498
00:22:15,160 --> 00:22:18,400
Speaker 3: axis ratios had to be something like five to one,

499
00:22:18,600 --> 00:22:20,800
Speaker 3: or maybe even as high as ten to one, and

500
00:22:20,880 --> 00:22:24,080
Speaker 3: the shape was kind of unclear. We say this because

501
00:22:24,119 --> 00:22:26,320
Speaker 3: if it were just that part of the surface was

502
00:22:26,440 --> 00:22:29,000
Speaker 3: dark and part of it was highly reflective, that can

503
00:22:29,080 --> 00:22:32,720
Speaker 3: only change the brightness so much as it rotates, and

504
00:22:32,800 --> 00:22:36,440
Speaker 3: the brightness variations are highly irregular, so that suggests it's

505
00:22:36,480 --> 00:22:39,639
Speaker 3: either like flat like a pancake, or long like a cigar,

506
00:22:39,800 --> 00:22:42,800
Speaker 3: and that it's tumbling doing this kind of uncontrolled rotation,

507
00:22:43,280 --> 00:22:47,359
Speaker 3: and sometimes we see the thin end of a muamua

508
00:22:47,480 --> 00:22:49,879
Speaker 3: and that's what it's hardly reflecting, and the light towards us,

509
00:22:49,880 --> 00:22:51,160
Speaker 3: and that's when it gets very dark.

510
00:22:51,280 --> 00:22:53,399
Speaker 2: So when you say brightness, you're not talking about this

511
00:22:53,440 --> 00:22:56,480
Speaker 2: thing glowing obviously, right, it's reflecting light from the sun.

512
00:22:56,640 --> 00:22:58,840
Speaker 5: That's right. All objects are going to reflect light from

513
00:22:58,880 --> 00:22:59,240
Speaker 5: the sun.

514
00:22:59,800 --> 00:23:02,840
Speaker 3: And if it's shaped like a pancake and as it's tumbling,

515
00:23:02,920 --> 00:23:05,399
Speaker 3: then when we see the whole pancake sort of face on,

516
00:23:05,960 --> 00:23:09,200
Speaker 3: then it's reflecting a lot more sunlight and it'll appear bright.

517
00:23:09,240 --> 00:23:11,399
Speaker 3: But then if we see it edge on, we'll hardly

518
00:23:11,400 --> 00:23:15,719
Speaker 3: see any sunlight reflective. We can try to infer the shape,

519
00:23:15,720 --> 00:23:19,400
Speaker 3: but it's a really inexact science. It's an unconstrained problem,

520
00:23:19,800 --> 00:23:22,359
Speaker 3: and so it's possible it's something like a ten to

521
00:23:22,440 --> 00:23:24,840
Speaker 3: one long cigar, like in a lot of the imagery

522
00:23:24,840 --> 00:23:27,119
Speaker 3: you might have seen online. There was an artist's picture

523
00:23:27,119 --> 00:23:31,159
Speaker 3: of it being almost needlelike, but I think most planetary

524
00:23:31,160 --> 00:23:34,280
Speaker 3: scientists think it's probably more like a flat pancake, maybe

525
00:23:34,440 --> 00:23:36,800
Speaker 3: six times wider than it is thick. If it were

526
00:23:36,800 --> 00:23:40,000
Speaker 3: shaped like a round rock than a sphere, then as

527
00:23:40,040 --> 00:23:42,760
Speaker 3: the sphere spins, we always see the same size. So

528
00:23:42,840 --> 00:23:45,280
Speaker 3: the only way that the brightness would vary is if

529
00:23:45,320 --> 00:23:47,280
Speaker 3: part of it was reflective and part of it was not.

530
00:23:47,440 --> 00:23:50,520
Speaker 3: Now that's normal. Things have dark areas and bright areas

531
00:23:50,520 --> 00:23:53,919
Speaker 3: on them, But we would see it change in exactly

532
00:23:54,000 --> 00:23:57,520
Speaker 3: the same pattern every rotation. And there's only so much

533
00:23:57,640 --> 00:24:01,199
Speaker 3: variation that you can get from from that sort of

534
00:24:01,920 --> 00:24:04,919
Speaker 3: a surface brightness changing. When you see this kind of

535
00:24:05,640 --> 00:24:10,679
Speaker 3: very irregular, very strong brightness variations, that's most naturally explained by.

536
00:24:10,600 --> 00:24:11,480
Speaker 5: A strain shape.

537
00:24:11,600 --> 00:24:14,480
Speaker 2: So imagine you had like a piece of charcoal and

538
00:24:14,680 --> 00:24:17,159
Speaker 2: half of it was dipped in white paint, so you know,

539
00:24:17,160 --> 00:24:19,520
Speaker 2: if you illuminated it, it looked like black and white, but

540
00:24:19,560 --> 00:24:22,560
Speaker 2: it's perfectly spherical and it's spinning. You're saying that we

541
00:24:22,600 --> 00:24:25,400
Speaker 2: would see a regular variation in the brightness. We would

542
00:24:25,400 --> 00:24:27,119
Speaker 2: see it bright and dark and bright and dark.

543
00:24:27,280 --> 00:24:30,920
Speaker 3: Right, you see almost a sinus soidal variation. And only

544
00:24:30,960 --> 00:24:33,800
Speaker 3: if you happen to be at that special orientation that

545
00:24:33,840 --> 00:24:37,800
Speaker 3: you got it completely white or completely black once a

546
00:24:37,880 --> 00:24:40,800
Speaker 3: rotation would those brightness variations be.

547
00:24:40,840 --> 00:24:43,000
Speaker 5: You know, ten to one or something extremely strong.

548
00:24:43,200 --> 00:24:45,280
Speaker 2: And so you're saying that what we saw were huge

549
00:24:45,320 --> 00:24:48,600
Speaker 2: variations in the brightness, and the pattern was kind of irregular,

550
00:24:49,000 --> 00:24:50,840
Speaker 2: meaning that we're not like seeing the same side of

551
00:24:50,880 --> 00:24:53,040
Speaker 2: it over and over. Is that what you mean by tumbling?

552
00:24:53,160 --> 00:24:54,520
Speaker 2: That is what I mean by tumbling.

553
00:24:54,640 --> 00:24:58,720
Speaker 3: So when something just spins, then every single rotation it

554
00:24:58,760 --> 00:25:01,440
Speaker 3: comes back to the same area, like the earth spinning

555
00:25:01,520 --> 00:25:03,720
Speaker 3: or something like that. But if you take an a

556
00:25:03,800 --> 00:25:06,960
Speaker 3: regularly shaped object, and the classic example here is something

557
00:25:07,080 --> 00:25:10,480
Speaker 3: like a chalk border eraser or a white border eraser,

558
00:25:11,080 --> 00:25:14,600
Speaker 3: if you try to spin it lengthwise, you'll find it

559
00:25:14,640 --> 00:25:15,960
Speaker 3: won't uniformly spin.

560
00:25:16,119 --> 00:25:18,119
Speaker 5: It'll start doing this very strange.

561
00:25:17,720 --> 00:25:21,879
Speaker 3: Irregular, almost kind of random flipping in the air in

562
00:25:21,920 --> 00:25:24,680
Speaker 3: all these different directions, and that's called tumbling. And when

563
00:25:24,680 --> 00:25:27,440
Speaker 3: that happens, you do not see this regular brightness variation.

564
00:25:27,560 --> 00:25:31,280
Speaker 3: And so Omuamua is definitely tumbling. And what that means

565
00:25:31,320 --> 00:25:33,639
Speaker 3: is it's very hard to model because it's almost a

566
00:25:33,720 --> 00:25:37,200
Speaker 3: random variation, and that's why it's so frustratingly difficult to

567
00:25:37,200 --> 00:25:38,679
Speaker 3: figure out what its actual shape is.

568
00:25:38,960 --> 00:25:41,480
Speaker 2: So does tumbling just means spinning on more than one

569
00:25:41,600 --> 00:25:42,800
Speaker 2: axis at the same time.

570
00:25:43,000 --> 00:25:45,520
Speaker 5: That's right, that's a good way of thinking about it.

571
00:25:45,560 --> 00:25:49,480
Speaker 3: Basically, the axis of rotation sort of changes with respect

572
00:25:49,600 --> 00:25:53,720
Speaker 3: to the shape of the object, and it's not regular.

573
00:25:54,040 --> 00:25:56,080
Speaker 3: This object is so small and so far away that

574
00:25:56,160 --> 00:25:58,720
Speaker 3: it's just a point of light, and so everything.

575
00:25:58,400 --> 00:26:00,680
Speaker 5: About it we have to infer. From that light.

576
00:26:00,760 --> 00:26:03,320
Speaker 3: We can watch it change its brightness and so try

577
00:26:03,320 --> 00:26:05,600
Speaker 3: and figure out what shapes would do that. We can

578
00:26:05,640 --> 00:26:08,720
Speaker 3: also look at how bright it is at different wavelengths,

579
00:26:09,119 --> 00:26:11,359
Speaker 3: and that helps us infer what the surface might be

580
00:26:11,440 --> 00:26:14,639
Speaker 3: made of based on what light gets reflective and what

581
00:26:14,720 --> 00:26:15,520
Speaker 3: light gets absorbed.

582
00:26:15,720 --> 00:26:18,320
Speaker 2: So we're looking at a single pixel in a telescope

583
00:26:18,359 --> 00:26:20,440
Speaker 2: and just watching it get darker and brighter, and from

584
00:26:20,480 --> 00:26:23,160
Speaker 2: that we have this crazy artist impression with all these

585
00:26:23,200 --> 00:26:25,639
Speaker 2: like crags and knooks and all these vinkles on it.

586
00:26:25,840 --> 00:26:27,040
Speaker 5: That's exactly right.

587
00:26:28,760 --> 00:26:29,200
Speaker 2: Crazy.

588
00:26:30,160 --> 00:26:32,840
Speaker 5: It really helps to imagine yourself there.

589
00:26:32,960 --> 00:26:35,520
Speaker 3: It really helps give you physical intuition for what's going on,

590
00:26:35,600 --> 00:26:37,600
Speaker 3: and so I think it's a really valuable exercise for

591
00:26:37,680 --> 00:26:40,000
Speaker 3: us to imagine what these things might look like. But

592
00:26:40,080 --> 00:26:42,320
Speaker 3: we always have to bring with that the caveat that

593
00:26:42,359 --> 00:26:45,480
Speaker 3: we have filled in way more details than we actually know,

594
00:26:45,720 --> 00:26:48,679
Speaker 3: and sometimes that can be frustrating when communicating to the public.

595
00:26:48,760 --> 00:26:51,480
Speaker 3: Trying to convey we are sure about this, but these

596
00:26:51,480 --> 00:26:54,159
Speaker 3: other details I'm showing you are just complete fiction and

597
00:26:54,200 --> 00:26:56,600
Speaker 3: could easily be wrong, like the crags right, the little

598
00:26:56,600 --> 00:26:59,040
Speaker 3: shapes on that long black cigar shape.

599
00:26:59,160 --> 00:27:01,800
Speaker 2: Especially in exo planet science, I feel like they're often

600
00:27:01,840 --> 00:27:05,359
Speaker 2: showing us essentially fantasy data. You know, this is what

601
00:27:05,400 --> 00:27:07,600
Speaker 2: an artist thinks this planet looks like, when really the

602
00:27:07,600 --> 00:27:09,080
Speaker 2: image we have is a single pixel.

603
00:27:10,040 --> 00:27:13,440
Speaker 3: Every planet around another star we've ever detected, We've only gotten,

604
00:27:13,720 --> 00:27:16,920
Speaker 3: you know, information from just just a point. Sometimes that

605
00:27:16,960 --> 00:27:19,520
Speaker 3: point is just the star and we can infer it's there,

606
00:27:20,080 --> 00:27:22,320
Speaker 3: and in a few cases we can actually image the planet,

607
00:27:22,320 --> 00:27:24,520
Speaker 3: but by that we just mean we see the star

608
00:27:24,560 --> 00:27:26,240
Speaker 3: in one part of the image and this little dot

609
00:27:26,280 --> 00:27:29,320
Speaker 3: that's the planet in another part of the image. Exoplanets

610
00:27:29,480 --> 00:27:33,520
Speaker 3: have a really special place in the imagination of, you know,

611
00:27:33,560 --> 00:27:36,800
Speaker 3: of the world, because unlike you know, a nebula or

612
00:27:36,840 --> 00:27:39,480
Speaker 3: a supernova or a gamma ray burst, a planet feels

613
00:27:39,480 --> 00:27:42,639
Speaker 3: like a place you know, that we could in principle visit,

614
00:27:42,960 --> 00:27:45,280
Speaker 3: and in science fiction where you know, we do go

615
00:27:45,359 --> 00:27:49,000
Speaker 3: and visit. And so the reason people are interested is

616
00:27:49,040 --> 00:27:50,840
Speaker 3: it's like, what would it be like if you were there.

617
00:27:50,880 --> 00:27:53,280
Speaker 3: You want to imagine what it's like if you were there.

618
00:27:53,359 --> 00:27:56,760
Speaker 3: It's one of the things that made planetary exploration so

619
00:27:56,960 --> 00:27:59,480
Speaker 3: compelling when we started to visit Venus and Mars and

620
00:27:59,560 --> 00:28:02,480
Speaker 3: Jupiter and Saturn, is that we actually send robots there

621
00:28:02,480 --> 00:28:05,160
Speaker 3: and we will even say we've been to Jupiter. Right, Okay,

622
00:28:05,160 --> 00:28:07,359
Speaker 3: we have not been to Jupiter, but we've got great

623
00:28:07,400 --> 00:28:10,360
Speaker 3: pictures that make us feel like we've been to Jupiter.

624
00:28:10,640 --> 00:28:13,960
Speaker 3: And so that's why you get these like NASA Exoplanet

625
00:28:14,000 --> 00:28:17,199
Speaker 3: Travel Bureau posters right where they're like advertising come to

626
00:28:17,240 --> 00:28:19,200
Speaker 3: this planet and they you know, all the cool stuff

627
00:28:19,240 --> 00:28:22,119
Speaker 3: and these very retro style those are really popular and

628
00:28:22,160 --> 00:28:24,520
Speaker 3: those are really fun for that reason, and it makes

629
00:28:24,600 --> 00:28:26,080
Speaker 3: exoplanets a lot of fun to study.

630
00:28:26,160 --> 00:28:29,320
Speaker 2: All right, but we're not selling Omuamua as a tourist destination.

631
00:28:29,920 --> 00:28:31,960
Speaker 2: We wanted to understand the shape of it because we

632
00:28:32,040 --> 00:28:33,919
Speaker 2: had sort of a deeper question, right, which was like,

633
00:28:34,400 --> 00:28:37,399
Speaker 2: is this thing weird or unusual? And so you were

634
00:28:37,440 --> 00:28:40,400
Speaker 2: saying that the initial idea was that it was long

635
00:28:40,480 --> 00:28:43,200
Speaker 2: and thin, sort of like ten times longer than it

636
00:28:43,240 --> 00:28:45,520
Speaker 2: is thin. But now we have another idea that maybe

637
00:28:45,560 --> 00:28:47,920
Speaker 2: it's flat, like a pancake. How can both of those

638
00:28:48,000 --> 00:28:49,640
Speaker 2: be consistent with the light variation?

639
00:28:49,960 --> 00:28:50,160
Speaker 5: Right?

640
00:28:50,200 --> 00:28:53,360
Speaker 3: And I think that's because it's tumbling, and so we

641
00:28:53,400 --> 00:28:56,120
Speaker 3: don't actually know what its orientation was because it's kind

642
00:28:56,120 --> 00:28:59,720
Speaker 3: of this random orientation and the data are really sparse,

643
00:29:00,040 --> 00:29:02,520
Speaker 3: you know. We don't get to point the Hubble Space

644
00:29:02,560 --> 00:29:05,840
Speaker 3: telescope at it constantly and follow its brightness all the time.

645
00:29:05,920 --> 00:29:07,400
Speaker 5: Only the largest telescopes.

646
00:29:07,720 --> 00:29:10,560
Speaker 3: Because it was so small it could make accurate brightness

647
00:29:10,560 --> 00:29:12,840
Speaker 3: measurements on the ground, you can only do it during

648
00:29:12,880 --> 00:29:14,719
Speaker 3: the day, and you know when you're allowed to use

649
00:29:14,760 --> 00:29:17,680
Speaker 3: the telescope. So you end up with this very sparse

650
00:29:17,800 --> 00:29:20,240
Speaker 3: data set where you only know it's brightness, you know,

651
00:29:20,320 --> 00:29:22,080
Speaker 3: for a few times. Maybe you get a bunch of

652
00:29:22,120 --> 00:29:23,880
Speaker 3: measurements over the course of a couple of days, and

653
00:29:23,920 --> 00:29:26,240
Speaker 3: then nothing for a month, And so you're trying to

654
00:29:26,800 --> 00:29:29,960
Speaker 3: infer the shape from very limited information, and it just

655
00:29:30,000 --> 00:29:33,080
Speaker 3: turns out there are multiple different shapes that plausibly could

656
00:29:33,080 --> 00:29:36,400
Speaker 3: do that depending on exactly how it's tumbling, which is random.

657
00:29:36,400 --> 00:29:36,920
Speaker 5: It can't be.

658
00:29:36,880 --> 00:29:39,280
Speaker 2: Predicted, And so then the shape is important to this

659
00:29:39,360 --> 00:29:43,240
Speaker 2: larger question of like what is it? Because the argument

660
00:29:43,320 --> 00:29:46,120
Speaker 2: is made that like long thin things are weird and

661
00:29:46,160 --> 00:29:49,400
Speaker 2: unusual and therefore might be alien. Is that the idea.

662
00:29:49,480 --> 00:29:53,320
Speaker 3: So Abby's point was that if you look at the

663
00:29:53,320 --> 00:29:56,880
Speaker 3: the most extreme models that fit the data, some of

664
00:29:56,920 --> 00:29:59,920
Speaker 3: them said the access ratio is ten to one to one,

665
00:30:00,200 --> 00:30:02,080
Speaker 3: and you know, we could also fit it with something

666
00:30:02,120 --> 00:30:03,400
Speaker 3: only five to one to one, and.

667
00:30:03,360 --> 00:30:04,640
Speaker 5: We could also fit it with pancakes.

668
00:30:04,640 --> 00:30:08,400
Speaker 3: But that was like the strangest and most extreme value

669
00:30:08,440 --> 00:30:11,479
Speaker 3: that people published as a possibility, and he really grabbed

670
00:30:11,520 --> 00:30:14,719
Speaker 3: onto that, and he argued that that's far beyond the

671
00:30:14,760 --> 00:30:17,360
Speaker 3: access ratio that we see in any object in the

672
00:30:17,360 --> 00:30:20,800
Speaker 3: Solar system, and so that automatically puts it in this

673
00:30:21,000 --> 00:30:24,000
Speaker 3: you know, that looks unnatural, that looks weird, that's something

674
00:30:24,000 --> 00:30:26,960
Speaker 3: else kind of category. And so that's when all these

675
00:30:26,960 --> 00:30:29,680
Speaker 3: caveats come in. This is a very small object. We

676
00:30:29,760 --> 00:30:32,880
Speaker 3: have very few examples of such small objects. But interestingly,

677
00:30:33,320 --> 00:30:35,920
Speaker 3: the objects in the Solar system that do have extreme

678
00:30:36,000 --> 00:30:38,520
Speaker 3: access ratio it's like five to five to one or something,

679
00:30:38,960 --> 00:30:42,560
Speaker 3: are also among the very smallest things in the solar system.

680
00:30:42,600 --> 00:30:46,600
Speaker 3: So it's very possible that very small objects often have

681
00:30:46,720 --> 00:30:48,920
Speaker 3: these kinds of access ratio. And you know, it's not

682
00:30:48,960 --> 00:30:51,120
Speaker 3: like we can't you know, come up with reasons why

683
00:30:51,160 --> 00:30:54,520
Speaker 3: that might be. If you take a bar of soap,

684
00:30:54,840 --> 00:30:56,720
Speaker 3: and you know, a bar of soap sitting there in

685
00:30:56,720 --> 00:30:59,360
Speaker 3: your shower, every time you take a shower, the soap

686
00:30:59,440 --> 00:31:02,080
Speaker 3: loses so and it kind of loses soap from all sides.

687
00:31:02,480 --> 00:31:05,440
Speaker 3: It doesn't just become a smaller, you know, rectangular prism

688
00:31:05,480 --> 00:31:09,200
Speaker 3: with every shower. It becomes flatter and flatter and thinner

689
00:31:09,240 --> 00:31:11,600
Speaker 3: and thinner until it's just like, you know, this little wafer.

690
00:31:12,480 --> 00:31:15,800
Speaker 3: And so whenever you erode something evenly on all sides,

691
00:31:16,360 --> 00:31:19,560
Speaker 3: that's sort of naturally what happens. If you start kind of,

692
00:31:19,960 --> 00:31:23,719
Speaker 3: you know, pancake shaped, you'll end up extremely pancake shaped.

693
00:31:24,120 --> 00:31:28,200
Speaker 3: So if this object is made of ices of some sort,

694
00:31:28,320 --> 00:31:32,040
Speaker 3: some very you know, cold stuff like like water ice

695
00:31:32,120 --> 00:31:34,880
Speaker 3: or carbon dioxide ice or nitogen ice or something like that,

696
00:31:35,640 --> 00:31:38,760
Speaker 3: then as that ice sublimates away, it would be very

697
00:31:38,800 --> 00:31:39,960
Speaker 3: natural for it to end.

698
00:31:39,920 --> 00:31:43,440
Speaker 5: Up having an access ratio like that. That makes sense.

699
00:31:43,640 --> 00:31:46,160
Speaker 3: That could be what's going on, But we have access

700
00:31:46,200 --> 00:31:48,880
Speaker 3: to so few objects of this size that it's just

701
00:31:48,880 --> 00:31:49,360
Speaker 3: a story.

702
00:31:49,360 --> 00:31:50,680
Speaker 5: But it's plausible, it makes sense.

703
00:31:51,040 --> 00:31:55,360
Speaker 3: The strangest thing about it is probably its orbit so

704
00:31:55,560 --> 00:31:57,640
Speaker 3: we caught it pretty late in the game. It had

705
00:31:57,680 --> 00:32:00,360
Speaker 3: already come in from interstellar space. It whipped around the Sun.

706
00:32:00,400 --> 00:32:03,040
Speaker 3: It was on its way out when it was discovered.

707
00:32:03,360 --> 00:32:05,280
Speaker 3: It happened to come very close to Earth then, and

708
00:32:05,320 --> 00:32:08,680
Speaker 3: then as it left the Solar System, because it was

709
00:32:08,880 --> 00:32:10,800
Speaker 3: the first time we'd seen such an object, it was

710
00:32:10,840 --> 00:32:13,520
Speaker 3: tracked pretty carefully by the Hubble Space telescope and other

711
00:32:13,560 --> 00:32:14,520
Speaker 3: telescopes on Earth.

712
00:32:14,720 --> 00:32:16,960
Speaker 5: And as we tracked its orbit, it did not.

713
00:32:17,240 --> 00:32:21,640
Speaker 3: Follow the orbit you would expect from just Newtonian gravity,

714
00:32:21,680 --> 00:32:24,440
Speaker 3: the orbits that the planets follow around the Sun. It

715
00:32:24,520 --> 00:32:27,200
Speaker 3: seemed to be getting some sort of a push away

716
00:32:27,200 --> 00:32:30,320
Speaker 3: from the Sun that made it slow down less than

717
00:32:30,320 --> 00:32:34,080
Speaker 3: you would think on its way out. So that's called

718
00:32:34,080 --> 00:32:38,200
Speaker 3: a non gravitational acceleration. It's not usually seen in large

719
00:32:38,200 --> 00:32:40,720
Speaker 3: objects like planets, because what could push a planet around

720
00:32:40,760 --> 00:32:41,520
Speaker 3: other than gravity.

721
00:32:42,280 --> 00:32:43,440
Speaker 5: Comets, on the other.

722
00:32:43,320 --> 00:32:46,600
Speaker 3: Hand, tend to have this a lot, and that's because

723
00:32:46,720 --> 00:32:49,160
Speaker 3: as they get close to the Sun, the ices on

724
00:32:49,200 --> 00:32:52,200
Speaker 3: their surfaces melt. They come off in these big jets,

725
00:32:52,640 --> 00:32:55,600
Speaker 3: and then from the rocket effect of that gas escaping

726
00:32:55,640 --> 00:32:58,400
Speaker 3: the surface of the comet, the comet will react and

727
00:32:58,440 --> 00:33:00,440
Speaker 3: move the other way. And so comets sort of propel

728
00:33:00,520 --> 00:33:03,280
Speaker 3: themselves by all of that gas coming off of their surface.

729
00:33:03,480 --> 00:33:05,800
Speaker 2: So, just so that I understand, you're saying, if you

730
00:33:05,920 --> 00:33:08,959
Speaker 2: dropped like an innert rock, rock that didn't have any rockets,

731
00:33:09,080 --> 00:33:11,720
Speaker 2: wasn't the spaceship had no way to apply a force.

732
00:33:11,880 --> 00:33:14,280
Speaker 2: We could predict very precisely how it would move in

733
00:33:14,320 --> 00:33:15,680
Speaker 2: the sun the gravitational field.

734
00:33:15,720 --> 00:33:17,720
Speaker 3: If it's a big enough rock that other things can't

735
00:33:17,720 --> 00:33:20,000
Speaker 3: push it around, that's right, it's going to follow a

736
00:33:20,160 --> 00:33:23,200
Speaker 3: very well defined curve. If you take an astronomy class,

737
00:33:23,240 --> 00:33:25,080
Speaker 3: you know it's got to be a circle and ellipse

738
00:33:25,480 --> 00:33:27,000
Speaker 3: or a problem or hyperbole.

739
00:33:27,080 --> 00:33:28,520
Speaker 5: These are the conic sections.

740
00:33:28,560 --> 00:33:32,280
Speaker 3: They are the solutions to Newton's equations for two objects

741
00:33:32,360 --> 00:33:34,680
Speaker 3: that are gravitationally attracted to each other.

742
00:33:34,760 --> 00:33:37,000
Speaker 2: And so one way to find out if something is

743
00:33:37,040 --> 00:33:39,360
Speaker 2: an alien ship, for example, is to see is it

744
00:33:39,480 --> 00:33:43,239
Speaker 2: moving under thrust? Basically, is it firing. Some engines like

745
00:33:43,320 --> 00:33:46,440
Speaker 2: the Space Shuttle or our ships don't obviously move just

746
00:33:46,520 --> 00:33:47,600
Speaker 2: in gravitational orbits.

747
00:33:47,680 --> 00:33:48,560
Speaker 5: Right, right, there's.

748
00:33:48,360 --> 00:33:52,120
Speaker 3: Actually two reasons you would expect an artificial object to

749
00:33:52,600 --> 00:33:55,880
Speaker 3: do this. Interestingly, one of the first claims of an

750
00:33:55,880 --> 00:34:00,240
Speaker 3: alien spaceship in the Solar System was under very very

751
00:34:00,240 --> 00:34:04,440
Speaker 3: similar reasoning. It was by Joseph Schklovsky, who was a

752
00:34:04,960 --> 00:34:09,120
Speaker 3: Soviet astronomer who co wrote a book with Carl Sagan

753
00:34:09,239 --> 00:34:12,360
Speaker 3: on Life in the Universe, and in that book he

754
00:34:12,480 --> 00:34:16,799
Speaker 3: described the difficulties in getting the orbit of Phobos, the

755
00:34:16,840 --> 00:34:19,439
Speaker 3: moon of Mars, which people were trying to predict where

756
00:34:19,440 --> 00:34:21,399
Speaker 3: the moon would be and it just wouldn't be where

757
00:34:21,400 --> 00:34:23,719
Speaker 3: it was supposed to be, and trying to figure out

758
00:34:23,719 --> 00:34:26,319
Speaker 3: what the problem was. Now, the problem was probably just

759
00:34:26,400 --> 00:34:28,560
Speaker 3: bad data at the time. It was a very faint

760
00:34:28,600 --> 00:34:32,040
Speaker 3: object to see back then. But one possibility Shklovsky pointed

761
00:34:32,080 --> 00:34:35,000
Speaker 3: out was that it was hollow. Now, why would being

762
00:34:35,040 --> 00:34:38,040
Speaker 3: hollow mean it doesn't follow a normal lunar orbit. The

763
00:34:38,120 --> 00:34:41,880
Speaker 3: reason is that the Sun's radiation actually carries with it

764
00:34:41,920 --> 00:34:44,640
Speaker 3: a little bit of momentum. When the solar photons hit you,

765
00:34:44,960 --> 00:34:47,640
Speaker 3: they're kind of gently nudging you away from the Sun. Now,

766
00:34:47,680 --> 00:34:50,279
Speaker 3: this is an incredibly weak effect, you'll never notice just

767
00:34:50,320 --> 00:34:53,560
Speaker 3: standing there. But if you have a light enough object

768
00:34:53,600 --> 00:34:57,719
Speaker 3: like a pebble orbiting the Sun, this actually matters, and

769
00:34:57,760 --> 00:35:00,440
Speaker 3: it will make that pebble's orbit around the Sun a

770
00:35:00,440 --> 00:35:03,880
Speaker 3: little different than you'd otherwise expect, and so Schklovsky's suggestion

771
00:35:04,480 --> 00:35:08,680
Speaker 3: was that despite being very large, many kilometers across that

772
00:35:08,719 --> 00:35:12,200
Speaker 3: Phobos was actually hollow, and so that photon pressure from

773
00:35:12,200 --> 00:35:14,879
Speaker 3: the Sun was enough because it hardly weighed anything because

774
00:35:14,880 --> 00:35:18,560
Speaker 3: it wasn't solid rock to alter its orbit. This didn't

775
00:35:18,600 --> 00:35:20,520
Speaker 3: really go anywhere. I think in the end they figured

776
00:35:20,560 --> 00:35:22,279
Speaker 3: out it really is just a rock. But it was

777
00:35:22,320 --> 00:35:25,200
Speaker 3: an early example of this, and so the same thing

778
00:35:25,239 --> 00:35:26,360
Speaker 3: could be happening.

779
00:35:26,440 --> 00:35:28,120
Speaker 5: AVI argues to omu.

780
00:35:27,920 --> 00:35:32,040
Speaker 3: Wa Mua that if it's actually not a big lump

781
00:35:32,120 --> 00:35:34,160
Speaker 3: of rock, but it's very thin, or it's hollow or

782
00:35:34,200 --> 00:35:37,600
Speaker 3: something like that, then the pressure from the solar photons

783
00:35:38,080 --> 00:35:40,880
Speaker 3: will push it away from the Sun much the way

784
00:35:40,920 --> 00:35:43,120
Speaker 3: that we saw it getting pushed away from the Sun.

785
00:35:43,600 --> 00:35:46,000
Speaker 3: So the argument was, you know, it could be a

786
00:35:46,000 --> 00:35:49,560
Speaker 3: comment and that's what we're seeing, or AVI says it

787
00:35:49,600 --> 00:35:52,800
Speaker 3: could be highly reflective and hardly weigh anything, and that would.

788
00:35:52,640 --> 00:35:56,000
Speaker 2: Do it too, basically if it's an alien light sale right.

789
00:35:56,320 --> 00:35:59,640
Speaker 3: So AVI works on a project called Breakthrough Starshot, and

790
00:35:59,680 --> 00:36:02,880
Speaker 3: the idea idea is to build spacecraft that can travel

791
00:36:03,120 --> 00:36:06,800
Speaker 3: interstellar distances to actually go and visit a nearby star system.

792
00:36:06,840 --> 00:36:11,520
Speaker 3: And the method that breakthrough Starshot proposes is to build

793
00:36:11,520 --> 00:36:14,200
Speaker 3: a light sail. So you have a very small spacecraft

794
00:36:14,200 --> 00:36:17,400
Speaker 3: and you attach it to a highly reflective sail, and

795
00:36:17,440 --> 00:36:20,440
Speaker 3: then you shoot a powerful laser at the sale, and

796
00:36:20,480 --> 00:36:24,319
Speaker 3: that powerful laser will then, through radiation pressure, accelerate it

797
00:36:24,360 --> 00:36:28,000
Speaker 3: to extremely high speeds if it's low enough mass. So

798
00:36:28,120 --> 00:36:31,319
Speaker 3: his suggestion was that this might be the method that

799
00:36:31,560 --> 00:36:35,640
Speaker 3: aliens around the galaxy use to propel their spacecraft. And

800
00:36:35,680 --> 00:36:38,600
Speaker 3: then once you get going, you know, those sales, perhaps

801
00:36:38,640 --> 00:36:41,120
Speaker 3: they get discarded or perhaps something hits them and they

802
00:36:41,120 --> 00:36:44,160
Speaker 3: fall off. But his argument is that the galaxy could

803
00:36:44,160 --> 00:36:46,560
Speaker 3: be littered with the detritus.

804
00:36:45,840 --> 00:36:47,239
Speaker 5: Of all of these launches.

805
00:36:48,040 --> 00:36:50,080
Speaker 3: And if that's the case, then we might expect now

806
00:36:50,120 --> 00:36:52,200
Speaker 3: and then one of these sales to come, you know,

807
00:36:52,360 --> 00:36:54,279
Speaker 3: through the solar system, and you'll be able to tell

808
00:36:54,320 --> 00:36:57,319
Speaker 3: it to sale because when light hits it, it pushes it

809
00:36:57,400 --> 00:37:00,160
Speaker 3: very easily. It has a very large surface area or

810
00:37:00,160 --> 00:37:03,160
Speaker 3: its mass, and you know it was designed so that

811
00:37:03,200 --> 00:37:05,080
Speaker 3: photons could push it around.

812
00:37:05,200 --> 00:37:07,760
Speaker 2: And then wouldn't you be able to predict very specifically

813
00:37:08,160 --> 00:37:10,080
Speaker 2: how that would move through our solar system? Like it

814
00:37:10,080 --> 00:37:12,280
Speaker 2: should get a bigger push when it's closer to the Sun,

815
00:37:12,840 --> 00:37:15,239
Speaker 2: a smaller push when it is further away. Did OMMA

816
00:37:15,360 --> 00:37:16,839
Speaker 2: follow that kind of trajectory?

817
00:37:17,040 --> 00:37:19,200
Speaker 3: Again, we only caught it on the way out, not

818
00:37:19,320 --> 00:37:21,400
Speaker 3: on the way in, so we don't have the complete

819
00:37:21,480 --> 00:37:25,120
Speaker 3: orbit for OMU, But from what we could tell, the

820
00:37:25,200 --> 00:37:29,720
Speaker 3: acceleration it felt, the non gravitational acceleration was entirely away

821
00:37:29,719 --> 00:37:33,160
Speaker 3: from the Sun. So that is consistent with solar photons

822
00:37:33,200 --> 00:37:36,760
Speaker 3: pushing on it. It's also consistent with a comment. Now,

823
00:37:37,040 --> 00:37:40,640
Speaker 3: there was just a little while ago a study that

824
00:37:40,800 --> 00:37:44,040
Speaker 3: looked at what if you had a sale, what, you know,

825
00:37:44,040 --> 00:37:46,359
Speaker 3: would it really all be just pushing away from the sun.

826
00:37:46,760 --> 00:37:49,960
Speaker 3: So we don't know, you know, how a sale would fold,

827
00:37:50,040 --> 00:37:52,240
Speaker 3: what it would be made of, you know what degrees

828
00:37:52,239 --> 00:37:54,880
Speaker 3: of freedom it has, what its shape would be, you know,

829
00:37:55,040 --> 00:37:56,120
Speaker 3: alien solar sales.

830
00:37:56,120 --> 00:37:58,080
Speaker 5: Who knows. So they just started with.

831
00:37:58,040 --> 00:38:00,920
Speaker 3: A simple toy model to see, you know, roughly what

832
00:38:00,960 --> 00:38:02,759
Speaker 3: we might expect. So they just said, okay, it's a

833
00:38:02,840 --> 00:38:05,960
Speaker 3: rigid sheet. Let's just take a rigid sheet, let it

834
00:38:06,000 --> 00:38:08,080
Speaker 3: get pushed by sunlight, throw it to the sun and

835
00:38:08,120 --> 00:38:11,080
Speaker 3: see what happens to it. Oh, and they made it tumble.

836
00:38:11,239 --> 00:38:13,440
Speaker 3: They didn't have it always present the same face to

837
00:38:13,480 --> 00:38:17,120
Speaker 3: the sun because we know Oua was tumbling. And what

838
00:38:17,160 --> 00:38:20,960
Speaker 3: they found was that most of the time the sheet

839
00:38:21,000 --> 00:38:24,080
Speaker 3: is not directly pointed at the Sun, which means when

840
00:38:24,080 --> 00:38:26,400
Speaker 3: the light reflects off of it, the push is not

841
00:38:26,480 --> 00:38:28,760
Speaker 3: directly away from the Sun, but off to the side

842
00:38:29,040 --> 00:38:32,279
Speaker 3: at some angle depending on how it's oriented. And so

843
00:38:32,480 --> 00:38:35,560
Speaker 3: as it flutters, as it tumbles, the push it receives

844
00:38:35,560 --> 00:38:37,879
Speaker 3: from the Sun will keep changing directions, but it will

845
00:38:37,920 --> 00:38:42,080
Speaker 3: often be lateral. It's not entirely away. And they found

846
00:38:42,120 --> 00:38:45,040
Speaker 3: that for their model anyway, that was inconsistent with the

847
00:38:45,160 --> 00:38:47,920
Speaker 3: orbit of omu Wa Mua. And so you can't rule

848
00:38:47,960 --> 00:38:50,680
Speaker 3: out any possible solar sail or whatnot. But they said,

849
00:38:50,680 --> 00:38:53,520
Speaker 3: if it's really thin and tumbling and it's radiation pressure,

850
00:38:53,600 --> 00:38:56,920
Speaker 3: you probably would have seen lateral acceleration. So it's probably

851
00:38:56,920 --> 00:38:57,640
Speaker 3: not a light sale.

852
00:38:57,719 --> 00:38:59,680
Speaker 2: So what have zigzagged more if it was a light.

853
00:38:59,560 --> 00:39:01,480
Speaker 5: Sail something like that.

854
00:39:01,520 --> 00:39:03,360
Speaker 3: I don't know the details about whether it would have

855
00:39:03,400 --> 00:39:06,560
Speaker 3: a preferential direction to the side. It probably depends on

856
00:39:06,600 --> 00:39:09,920
Speaker 3: exactly how it's being pushed. Now, Avi's big argument for

857
00:39:10,000 --> 00:39:14,879
Speaker 3: why it needed to be radiation pressure, and not commentary outgassing.

858
00:39:15,560 --> 00:39:19,200
Speaker 3: Is that a Muhamua never showed a coma. Most comments

859
00:39:19,239 --> 00:39:21,399
Speaker 3: when they get close to the sun, they start evaporating

860
00:39:21,520 --> 00:39:24,440
Speaker 3: their ices and that forms a cloud that reflects a

861
00:39:24,440 --> 00:39:26,440
Speaker 3: lot of sunlight and they get bright and then some

862
00:39:26,560 --> 00:39:28,560
Speaker 3: of that cloud goes off the back and that's their tail.

863
00:39:29,400 --> 00:39:33,600
Speaker 3: Muhamoua never showed evidence of a coma. In addition, we

864
00:39:33,719 --> 00:39:36,160
Speaker 3: looked carefully to see if we could detect any gases

865
00:39:36,200 --> 00:39:39,600
Speaker 3: around it, and the Spitzer space telescope couldn't find any,

866
00:39:40,320 --> 00:39:42,960
Speaker 3: and so to AVI, this is pretty conclusive that it's

867
00:39:43,000 --> 00:39:45,640
Speaker 3: not a comet, that it was not outgassing, and it

868
00:39:45,719 --> 00:39:47,920
Speaker 3: must have been reflection. And if it's reflection, it must

869
00:39:47,960 --> 00:39:50,600
Speaker 3: have been low mass, which means it must be artificial. Now,

870
00:39:50,760 --> 00:39:53,560
Speaker 3: a lot of planetary scientists subjected to this. It could

871
00:39:53,600 --> 00:39:56,359
Speaker 3: be made of a strange kind of ice. After all,

872
00:39:56,400 --> 00:39:59,000
Speaker 3: this is an interstellar comet. It's the first one we've seen.

873
00:39:59,040 --> 00:40:01,600
Speaker 3: Who knows, you know, what common out there. So my

874
00:40:01,760 --> 00:40:04,239
Speaker 3: colleague Steve Dash has proposed that it is made of

875
00:40:04,360 --> 00:40:05,280
Speaker 3: nitrogen ice.

876
00:40:05,800 --> 00:40:08,880
Speaker 5: We know nitrogen ice exists. The surface of Pluto has

877
00:40:08,920 --> 00:40:11,040
Speaker 5: big regions. That's just nitrogen ice.

878
00:40:11,080 --> 00:40:13,279
Speaker 3: And here I mean if you get you know, the

879
00:40:13,360 --> 00:40:16,640
Speaker 3: area breathing cold enough, you know, first you'll get the

880
00:40:16,680 --> 00:40:19,520
Speaker 3: liquid nitrogen. And then if you get that liquid nitrogen

881
00:40:19,960 --> 00:40:22,640
Speaker 3: much much colder, it'll turn solid. And that's what I'm

882
00:40:22,680 --> 00:40:25,839
Speaker 3: talking about. This is so cold that it's solid nitrogen ice.

883
00:40:26,239 --> 00:40:28,280
Speaker 3: And that actually fits the data very well.

884
00:40:28,160 --> 00:40:29,719
Speaker 5: If it's a chunk of nitrogen ice.

885
00:40:30,040 --> 00:40:32,439
Speaker 2: So we're talking about a chunk of nitrogen ice coming

886
00:40:32,480 --> 00:40:34,840
Speaker 2: through the Solar system, and then the Sun is heating

887
00:40:34,840 --> 00:40:38,319
Speaker 2: it up and the nitrogen boils off, and that's effectively

888
00:40:38,400 --> 00:40:41,160
Speaker 2: like a little rocket. So the comet is getting non

889
00:40:41,160 --> 00:40:45,120
Speaker 2: gravitational acceleration because it's pushing out all those nitrogen atoms,

890
00:40:45,480 --> 00:40:47,680
Speaker 2: and that's effectively how a rocket works. So it's like

891
00:40:47,680 --> 00:40:50,080
Speaker 2: a natural rocket on the back of a comet. That's

892
00:40:50,120 --> 00:40:50,640
Speaker 2: what you're saying.

893
00:40:50,719 --> 00:40:53,160
Speaker 3: That's exactly right, and that's how all commets work. The

894
00:40:53,280 --> 00:40:57,720
Speaker 3: question was, with this apparent comet, why didn't we see

895
00:40:57,760 --> 00:41:00,400
Speaker 3: all of this dust and gas around it? And so

896
00:41:00,719 --> 00:41:03,200
Speaker 3: the answer needs to be it's a very clean commet.

897
00:41:03,239 --> 00:41:05,120
Speaker 3: It doesn't have a lot of dust to blow off,

898
00:41:05,440 --> 00:41:07,879
Speaker 3: and the gas must be something we didn't look for,

899
00:41:08,000 --> 00:41:11,759
Speaker 3: like nitrogen there's another suggestion that it might be hydrogenized,

900
00:41:11,760 --> 00:41:12,360
Speaker 3: which would.

901
00:41:12,160 --> 00:41:15,080
Speaker 5: Be pretty exotic. We don't know that hydrogen ized can

902
00:41:15,120 --> 00:41:16,840
Speaker 5: even exist in space, but it's.

903
00:41:16,680 --> 00:41:19,560
Speaker 3: A possibility, and that might also fit the data pretty well.

904
00:41:20,040 --> 00:41:22,200
Speaker 3: So these are kind of out there explanations. We haven't

905
00:41:22,200 --> 00:41:24,360
Speaker 3: seen something like that in the Solar System, or at

906
00:41:24,440 --> 00:41:27,480
Speaker 3: least we haven't obviously seen something like that in the

907
00:41:27,520 --> 00:41:28,160
Speaker 3: Solar system.

908
00:41:28,200 --> 00:41:30,240
Speaker 5: There are so called dark comets.

909
00:41:30,760 --> 00:41:34,680
Speaker 3: These are clearly commets that're clearly outgassing, because we see

910
00:41:34,719 --> 00:41:39,319
Speaker 3: these non gravitational accelerations, but they don't have comi, they

911
00:41:39,320 --> 00:41:41,600
Speaker 3: don't have tails, and it's hard to find the gas

912
00:41:41,640 --> 00:41:44,160
Speaker 3: around them, and so it could just be that these

913
00:41:44,239 --> 00:41:47,600
Speaker 3: dark comets weren't really recognized as being important and interesting

914
00:41:47,680 --> 00:41:50,719
Speaker 3: and characteristic of the first thing we'd have.

915
00:41:50,719 --> 00:41:51,960
Speaker 5: Come through the Solar system.

916
00:41:52,120 --> 00:41:54,359
Speaker 2: So you're saying that there are other examples in our

917
00:41:54,480 --> 00:41:58,880
Speaker 2: Solar system of non gravitational acceleration without obvious outgassing with

918
00:41:59,000 --> 00:42:01,360
Speaker 2: no tail kind of thing. We've seen it before.

919
00:42:01,960 --> 00:42:05,719
Speaker 3: Yes, yes, we've discovered many more of them recently. I

920
00:42:05,719 --> 00:42:08,520
Speaker 3: think Omumua has spurred a lot of interest in them.

921
00:42:08,560 --> 00:42:23,759
Speaker 3: But yes, there are examples like that.

922
00:42:23,760 --> 00:42:26,440
Speaker 2: That's sort of. My other question is one line of

923
00:42:26,520 --> 00:42:29,800
Speaker 2: argument you're making is this thing is small and weird,

924
00:42:30,040 --> 00:42:32,799
Speaker 2: and it might just seem weird because we haven't seen

925
00:42:32,840 --> 00:42:35,799
Speaker 2: the small stuff in our solar system, and so when

926
00:42:35,840 --> 00:42:37,920
Speaker 2: we compare it to the big stuff, it seems weird.

927
00:42:37,960 --> 00:42:40,279
Speaker 2: But then why did we see omuumu If the small

928
00:42:40,280 --> 00:42:42,320
Speaker 2: stuff in our solar system is hard for us to see,

929
00:42:42,520 --> 00:42:44,240
Speaker 2: why did we even see Omuamua.

930
00:42:44,280 --> 00:42:47,640
Speaker 3: Well, one thing, it's very hard to see very small objects,

931
00:42:47,680 --> 00:42:49,560
Speaker 3: so it's not surprising it took a long time to

932
00:42:49,600 --> 00:42:52,799
Speaker 3: find something that small. Secondly, it's got to get very

933
00:42:52,800 --> 00:42:55,640
Speaker 3: close to Earth. Things orbiting the Sun sort of have

934
00:42:55,800 --> 00:42:58,880
Speaker 3: preferential orbits. There are certain places we find them, and

935
00:42:58,920 --> 00:43:01,400
Speaker 3: they tend not to come very close to Earth because

936
00:43:01,400 --> 00:43:03,800
Speaker 3: anything that comes close to Earth will feel Earth's gravity

937
00:43:03,880 --> 00:43:05,880
Speaker 3: and get perturbed, and then it won't be in that

938
00:43:06,000 --> 00:43:09,799
Speaker 3: orbit anymore. And after five billion years, you know, all

939
00:43:09,840 --> 00:43:12,359
Speaker 3: those things will have been cleared out. So you need

940
00:43:12,400 --> 00:43:15,600
Speaker 3: something on a strange, temporary orbit. It's not gonna last long.

941
00:43:15,640 --> 00:43:18,520
Speaker 3: That comes by, gets deflected by the Earth and it's gone.

942
00:43:18,600 --> 00:43:21,719
Speaker 3: So interstellar objects don't care about that. They just go

943
00:43:21,760 --> 00:43:23,840
Speaker 3: where they go. If they get perturbed. They get perturbed

944
00:43:23,840 --> 00:43:25,600
Speaker 3: because you know they're not going to be around for

945
00:43:25,680 --> 00:43:29,680
Speaker 3: long anyway, it doesn't matter. So it's not that surprising

946
00:43:29,920 --> 00:43:32,279
Speaker 3: that we don't see these very small objects super close

947
00:43:32,320 --> 00:43:34,359
Speaker 3: to Earth if they're orbiting the Sun. But I think

948
00:43:34,400 --> 00:43:36,160
Speaker 3: the real answer is just they're hard to find. You've

949
00:43:36,160 --> 00:43:38,200
Speaker 3: got to get incredibly lucky, and for the reason I

950
00:43:38,280 --> 00:43:40,480
Speaker 3: just said, you're more likely to get lucky apparently with

951
00:43:40,600 --> 00:43:42,600
Speaker 3: these interstellar.

952
00:43:42,120 --> 00:43:44,319
Speaker 2: Ones and for a Mumu. There's a detail that I

953
00:43:44,400 --> 00:43:47,279
Speaker 2: never understood which released specifically to that, which is that

954
00:43:47,320 --> 00:43:49,799
Speaker 2: we only saw it after it was moving away from us.

955
00:43:49,800 --> 00:43:51,880
Speaker 2: Why didn't we see it when it was closer to us?

956
00:43:51,920 --> 00:43:53,240
Speaker 2: Isn't that when it would have been easiest.

957
00:43:53,400 --> 00:43:55,160
Speaker 5: No, No, we did see it when it was closest

958
00:43:55,160 --> 00:43:58,040
Speaker 5: to the Earth, or not long after. It was closest

959
00:43:58,120 --> 00:44:00,520
Speaker 5: to the Earth in and out of the Soul system

960
00:44:00,560 --> 00:44:02,080
Speaker 5: has to do with where it was with respect to

961
00:44:02,120 --> 00:44:04,759
Speaker 5: the Sun. So as it approached the Sun, it was

962
00:44:04,800 --> 00:44:07,319
Speaker 5: pretty far away from Earth. I don't remember the exact orbit.

963
00:44:07,360 --> 00:44:09,560
Speaker 5: It may have even been in the same direction as

964
00:44:09,600 --> 00:44:12,279
Speaker 5: the Sun from Earth's perspective, in which case you.

965
00:44:12,520 --> 00:44:14,319
Speaker 3: Have no hope to see it during the day, and

966
00:44:14,400 --> 00:44:16,440
Speaker 3: it was only on its way out that it was

967
00:44:16,480 --> 00:44:20,279
Speaker 3: both close to the Earth and visible at night. And

968
00:44:20,320 --> 00:44:23,120
Speaker 3: then we got very lucky with its discovery in the

969
00:44:23,160 --> 00:44:24,640
Speaker 3: pan Star's survey.

970
00:44:24,560 --> 00:44:27,520
Speaker 2: So its closest approach to the Sun was before it

971
00:44:27,560 --> 00:44:30,160
Speaker 2: came by the Earth, which is when we spotted it.

972
00:44:30,280 --> 00:44:33,560
Speaker 2: So one lesson from Omulamua might be, hey, there's a

973
00:44:33,560 --> 00:44:36,360
Speaker 2: bunch of interesting tiny stuff in our solar system. We

974
00:44:36,360 --> 00:44:38,960
Speaker 2: should understand it better so that when tiny stuff from

975
00:44:38,960 --> 00:44:41,799
Speaker 2: other solar systems comes through we have more context. Is

976
00:44:41,800 --> 00:44:42,480
Speaker 2: that the message?

977
00:44:42,560 --> 00:44:45,719
Speaker 5: I think that's very important. I think all of this discussion.

978
00:44:45,239 --> 00:44:49,239
Speaker 3: On Amula Mua has really made these objects perhaps seem

979
00:44:49,280 --> 00:44:52,160
Speaker 3: more interesting and spurred a lot of interest in them,

980
00:44:52,480 --> 00:44:55,719
Speaker 3: because it doesn't seem right that the very first interstellar

981
00:44:55,760 --> 00:44:59,320
Speaker 3: object we see would be something that has no analogs

982
00:44:59,320 --> 00:45:02,279
Speaker 3: in our own soul system. And we're very interested in

983
00:45:02,320 --> 00:45:06,080
Speaker 3: these interstellar objects because we have very few examples of

984
00:45:06,120 --> 00:45:08,960
Speaker 3: material that's not from our own solar system, and principle,

985
00:45:09,280 --> 00:45:13,120
Speaker 3: these things probably formed when the planets in other stellar

986
00:45:13,160 --> 00:45:16,560
Speaker 3: systems were forming, and those are hard to study because

987
00:45:16,560 --> 00:45:19,000
Speaker 3: they're very far away. But if little, you know, bits

988
00:45:19,040 --> 00:45:23,359
Speaker 3: of stuff gets flung out of those and comes here

989
00:45:23,360 --> 00:45:24,800
Speaker 3: to Earth and just you know, sort of lands in

990
00:45:24,840 --> 00:45:25,400
Speaker 3: our lap.

991
00:45:25,760 --> 00:45:27,720
Speaker 5: That's a great way to study these other systems.

992
00:45:27,760 --> 00:45:30,080
Speaker 3: Not that we can tell exactly which system it came from,

993
00:45:30,440 --> 00:45:32,719
Speaker 3: but you know, in principle, just in general, to see

994
00:45:32,719 --> 00:45:36,040
Speaker 3: what other fragments of planets from other sellar systems might

995
00:45:36,080 --> 00:45:37,840
Speaker 3: be like is super interesting.

996
00:45:38,200 --> 00:45:41,399
Speaker 2: So another topic that people mentioned a lot when Omumua

997
00:45:41,600 --> 00:45:44,600
Speaker 2: was discovered was that it seems surprising that we found

998
00:45:44,600 --> 00:45:47,759
Speaker 2: one so quickly. As soon as we turned on this telescope,

999
00:45:47,960 --> 00:45:51,120
Speaker 2: very shortly afterwards, we found this weird object objects which

1000
00:45:51,120 --> 00:45:54,320
Speaker 2: people expected to be very very rare. I remember reading

1001
00:45:54,320 --> 00:45:56,520
Speaker 2: this argument that for us to see one so quickly,

1002
00:45:56,800 --> 00:45:58,719
Speaker 2: basically every star in the Milky Way would have to

1003
00:45:58,719 --> 00:46:02,000
Speaker 2: have and eject like ten to the fifteen objects during

1004
00:46:02,000 --> 00:46:05,040
Speaker 2: its lifetime for us to so quickly see one. What's

1005
00:46:05,080 --> 00:46:07,640
Speaker 2: the understanding now is now do we understand that while

1006
00:46:07,880 --> 00:46:10,719
Speaker 2: really stars are creating lots of these stellar debris and

1007
00:46:10,719 --> 00:46:12,160
Speaker 2: flinging around the Solar System.

1008
00:46:12,200 --> 00:46:15,080
Speaker 3: So first of all, we didn't detect a Mua MUAs

1009
00:46:15,239 --> 00:46:17,879
Speaker 3: as soon as possible. The Pan star survey has been

1010
00:46:17,880 --> 00:46:20,600
Speaker 3: going on for over ten years. It's just very hard

1011
00:46:20,640 --> 00:46:22,839
Speaker 3: to detect something this small. You have to really get

1012
00:46:22,920 --> 00:46:24,680
Speaker 3: lucky that you just happen to catch it when.

1013
00:46:24,520 --> 00:46:25,360
Speaker 5: It's close to Earth.

1014
00:46:25,800 --> 00:46:27,279
Speaker 3: So it's not that we found when as soon as

1015
00:46:27,320 --> 00:46:30,920
Speaker 3: we started looking. Rather, when people calculated how many of

1016
00:46:30,960 --> 00:46:33,960
Speaker 3: these things they expected there to be in the galaxy,

1017
00:46:34,880 --> 00:46:37,839
Speaker 3: it was thought that these surveys wouldn't get lucky enough

1018
00:46:37,880 --> 00:46:38,439
Speaker 3: to see one.

1019
00:46:38,640 --> 00:46:42,920
Speaker 5: But remember these guesses are based on our.

1020
00:46:42,840 --> 00:46:45,360
Speaker 3: Understanding of planet formation, for which we've never had a

1021
00:46:45,360 --> 00:46:48,319
Speaker 3: physical sample. A lot of these models are, you know,

1022
00:46:48,560 --> 00:46:51,160
Speaker 3: just trying to understand what's going on inside of these

1023
00:46:51,160 --> 00:46:53,920
Speaker 3: proto planetsary nebula where you can't really see what's going.

1024
00:46:53,800 --> 00:46:55,839
Speaker 5: On, especially objects of this size.

1025
00:46:56,640 --> 00:47:01,200
Speaker 3: Those estimates really strongly depend on how many things there

1026
00:47:01,239 --> 00:47:04,520
Speaker 3: are at different sizes. So generally you know there's gonna

1027
00:47:04,520 --> 00:47:07,080
Speaker 3: be a lot of big rocks orbiting a star, and

1028
00:47:07,120 --> 00:47:09,440
Speaker 3: then more medium rocks, and then lots and lots of

1029
00:47:09,440 --> 00:47:13,239
Speaker 3: little tiny ones, And the total number of rocks strongly

1030
00:47:13,280 --> 00:47:16,480
Speaker 3: depends on how sort of steep that relationship is. So

1031
00:47:16,520 --> 00:47:19,320
Speaker 3: for every one rock that's a kilometer across, how many

1032
00:47:19,640 --> 00:47:22,440
Speaker 3: are one hundred meters across? Is it is ten times

1033
00:47:22,440 --> 00:47:24,600
Speaker 3: as many? Is it twenty times as many, is it

1034
00:47:24,640 --> 00:47:27,040
Speaker 3: two hundred times as many? And so on all the

1035
00:47:27,080 --> 00:47:30,840
Speaker 3: way down to the size of omumamua, And that's really unknown.

1036
00:47:30,920 --> 00:47:34,359
Speaker 3: We just don't know how many little objects there should be.

1037
00:47:34,440 --> 00:47:37,279
Speaker 3: So the you know, the number that get ejected for

1038
00:47:37,440 --> 00:47:39,480
Speaker 3: star required for us to have seen one is a

1039
00:47:39,520 --> 00:47:43,279
Speaker 3: little on the high end of what we expected, but

1040
00:47:43,840 --> 00:47:48,279
Speaker 3: it's not completely outrageous. And that number also depends on

1041
00:47:48,360 --> 00:47:51,480
Speaker 3: how reflective and shiny they are. This object seems to

1042
00:47:51,480 --> 00:47:55,400
Speaker 3: be extremely reflective, like it's pure ice. That makes the

1043
00:47:55,440 --> 00:47:58,960
Speaker 3: smaller ones much easier to detect than those previous estimates

1044
00:47:59,000 --> 00:47:59,600
Speaker 3: would have guessed.

1045
00:48:00,080 --> 00:48:02,680
Speaker 2: So even just by getting one or two objects, we

1046
00:48:02,719 --> 00:48:06,279
Speaker 2: can infer something about the broader population of zillions and

1047
00:48:06,400 --> 00:48:07,320
Speaker 2: zillions of objects.

1048
00:48:07,360 --> 00:48:09,640
Speaker 3: That's really fascinating, right, Yeah, in order for us to

1049
00:48:09,640 --> 00:48:11,520
Speaker 3: have seen one by now, there must have been a lot,

1050
00:48:11,560 --> 00:48:11,719
Speaker 3: and I.

1051
00:48:11,680 --> 00:48:13,000
Speaker 5: Should point out we now have two.

1052
00:48:13,320 --> 00:48:17,360
Speaker 3: There's also common borisofv So shortly after a muhama, a

1053
00:48:17,480 --> 00:48:20,800
Speaker 3: second comment, interstellar comment was discovered, and it actually looks

1054
00:48:20,840 --> 00:48:21,640
Speaker 3: a lot like we.

1055
00:48:21,680 --> 00:48:23,640
Speaker 5: Expected Intersteller comments to look.

1056
00:48:23,760 --> 00:48:26,080
Speaker 3: So I don't know whether that makes a muamoa weirder

1057
00:48:26,280 --> 00:48:28,799
Speaker 3: or more ordinary. It kind of goes both ways. It

1058
00:48:28,840 --> 00:48:31,840
Speaker 3: means that, yes, it's not weird that we found a muhama.

1059
00:48:31,920 --> 00:48:34,360
Speaker 3: We found Borisov too. On the other hand, Borisoft doesn't

1060
00:48:34,360 --> 00:48:36,200
Speaker 3: look like a muhama. So there's at least two different

1061
00:48:36,239 --> 00:48:37,000
Speaker 3: kinds of these comments.

1062
00:48:37,000 --> 00:48:39,799
Speaker 2: Apparently, and in the context of the question of like

1063
00:48:40,040 --> 00:48:43,439
Speaker 2: is this a natural object or an alien object? It's

1064
00:48:43,680 --> 00:48:47,120
Speaker 2: not implausible. You're saying that there could be enormous numbers

1065
00:48:47,160 --> 00:48:50,920
Speaker 2: of these bits and pieces of other Solar systems floating around,

1066
00:48:51,360 --> 00:48:52,759
Speaker 2: rainy down on us occasionally.

1067
00:48:52,920 --> 00:48:54,280
Speaker 5: It's in fact quite expected.

1068
00:48:54,600 --> 00:48:58,799
Speaker 3: Like we know that the planet formation process kicks out

1069
00:48:59,120 --> 00:49:02,120
Speaker 3: the building blocks, planets, little asteroids, little commets. We know

1070
00:49:02,239 --> 00:49:04,400
Speaker 3: that that happens, and we still see that in the

1071
00:49:04,440 --> 00:49:07,399
Speaker 3: Solar System because Jupiter knocked a lot of these things

1072
00:49:07,440 --> 00:49:10,520
Speaker 3: during planet formation out of the Solar System. We know

1073
00:49:10,640 --> 00:49:14,000
Speaker 3: that because some small fraction of those things that kicked

1074
00:49:14,000 --> 00:49:16,000
Speaker 3: out of the Solar System didn't quite make it. They

1075
00:49:16,000 --> 00:49:18,040
Speaker 3: got far from the Sun, they slowed down, slow down

1076
00:49:18,040 --> 00:49:20,040
Speaker 3: from the Sun's gravity, and the Sun just barely held

1077
00:49:20,080 --> 00:49:22,680
Speaker 3: on to them. And now they orbit the Sun in

1078
00:49:22,719 --> 00:49:25,319
Speaker 3: the Orc cloud and occasionally come and visit us as

1079
00:49:25,360 --> 00:49:28,600
Speaker 3: long period commets, and so you know, you can tell

1080
00:49:28,640 --> 00:49:30,759
Speaker 3: from the number of comets that come in how many

1081
00:49:31,200 --> 00:49:34,400
Speaker 3: didn't get fully ejected, and from that try to extrapolate

1082
00:49:34,440 --> 00:49:36,560
Speaker 3: to how many must have successfully been ejected.

1083
00:49:36,640 --> 00:49:37,239
Speaker 5: And it's a lot.

1084
00:49:37,360 --> 00:49:39,960
Speaker 2: But in comparison for us to see, for example, a

1085
00:49:40,000 --> 00:49:42,400
Speaker 2: piece of alien junk, it would mean that the galaxy

1086
00:49:42,400 --> 00:49:45,520
Speaker 2: has to be like overflowing with alien junk, right, Like

1087
00:49:45,800 --> 00:49:47,920
Speaker 2: if we're seeing a light sale, that would suggest that

1088
00:49:47,960 --> 00:49:50,960
Speaker 2: there are like ten to the fifteen alien junk light

1089
00:49:51,040 --> 00:49:52,320
Speaker 2: sales out there as well.

1090
00:49:52,520 --> 00:49:55,560
Speaker 3: So Audi's hypothesis is that it is very common to

1091
00:49:55,640 --> 00:49:59,759
Speaker 3: launch large numbers of spacecraft with light sails, and that

1092
00:50:00,200 --> 00:50:04,000
Speaker 3: the galaxy is just filled with the litter from all

1093
00:50:04,040 --> 00:50:06,600
Speaker 3: of these space launches all the time. So yeah, you

1094
00:50:06,640 --> 00:50:11,840
Speaker 3: have to imagine sort of a pangalactic technology that's sending

1095
00:50:11,920 --> 00:50:13,200
Speaker 3: ships from star to star.

1096
00:50:13,080 --> 00:50:13,720
Speaker 5: All the time.

1097
00:50:13,760 --> 00:50:17,800
Speaker 2: Wow, well, that is a large hypothesis to consider. Let's

1098
00:50:17,800 --> 00:50:21,440
Speaker 2: also talk about the velocity of this object. I understand

1099
00:50:21,480 --> 00:50:23,840
Speaker 2: that it had a sort of unusual or unexpected speed

1100
00:50:23,880 --> 00:50:25,880
Speaker 2: as it entered the Solar System, right.

1101
00:50:25,760 --> 00:50:28,080
Speaker 3: So there's a big caveat which is that we don't

1102
00:50:28,200 --> 00:50:30,920
Speaker 3: know how it entered the Solar System, because that depends

1103
00:50:31,320 --> 00:50:35,400
Speaker 3: on the amount of non gravitational acceleration that it experienced,

1104
00:50:36,000 --> 00:50:38,799
Speaker 3: and it depends on how much mass it lost. So

1105
00:50:39,000 --> 00:50:43,839
Speaker 3: under the ice models, I think we favor most it

1106
00:50:43,920 --> 00:50:47,920
Speaker 3: lost something like ninety percent of its mass as it

1107
00:50:48,000 --> 00:50:50,719
Speaker 3: warmed up and got near the Sun, which means it

1108
00:50:50,760 --> 00:50:54,720
Speaker 3: experienced a lot of non gravitational acceleration before we even

1109
00:50:54,840 --> 00:50:57,200
Speaker 3: saw it. But we don't really know how much that.

1110
00:50:57,400 --> 00:50:59,600
Speaker 2: Big error bars on there, So it could have been

1111
00:50:59,600 --> 00:51:01,840
Speaker 2: a huge bar of soap as it approached the Solar

1112
00:51:01,840 --> 00:51:03,920
Speaker 2: system and then we just saw a little sliver after

1113
00:51:04,080 --> 00:51:05,320
Speaker 2: it got melted by the Sun.

1114
00:51:05,440 --> 00:51:08,200
Speaker 5: That's exactly right. That could very easily be what happened.

1115
00:51:08,200 --> 00:51:12,400
Speaker 3: And with big uncertainties like that, it's hard to extrapolate

1116
00:51:12,520 --> 00:51:14,360
Speaker 3: backwards and get.

1117
00:51:14,200 --> 00:51:15,839
Speaker 5: An accurate reading on how it came in.

1118
00:51:16,040 --> 00:51:18,440
Speaker 3: Now, if we do our best and say, you know,

1119
00:51:18,640 --> 00:51:21,799
Speaker 3: where did it probably come from, then the direction it

1120
00:51:21,840 --> 00:51:25,440
Speaker 3: came from is kind of interesting. It's basically exactly the

1121
00:51:25,560 --> 00:51:29,560
Speaker 3: direction the Sun is headed through the galaxy, and the

1122
00:51:29,600 --> 00:51:33,120
Speaker 3: speed it came in at is basically exactly the speed

1123
00:51:33,280 --> 00:51:37,520
Speaker 3: of the Sun through the galaxy, which means it was

1124
00:51:37,560 --> 00:51:39,520
Speaker 3: basically from the galaxy's perspective.

1125
00:51:39,920 --> 00:51:43,479
Speaker 5: Sitting still, it wasn't moving at all. We ran into it,

1126
00:51:44,000 --> 00:51:45,880
Speaker 5: and that's very.

1127
00:51:45,600 --> 00:51:48,200
Speaker 3: Interesting, and so some people have tried to hypothesize what

1128
00:51:48,239 --> 00:51:51,719
Speaker 3: that could mean. We suspect that this thing was kicked

1129
00:51:51,719 --> 00:51:55,160
Speaker 3: out of a young stellar system when its planets were forming,

1130
00:51:55,160 --> 00:51:58,680
Speaker 3: So a new star that had been born, say millions

1131
00:51:58,719 --> 00:52:03,160
Speaker 3: of years ago or something like that, and stars form

1132
00:52:03,320 --> 00:52:07,440
Speaker 3: out of clouds of gas, and clouds of gas typically

1133
00:52:07,480 --> 00:52:10,560
Speaker 3: are kind of stationary in the galaxy. So everything orbits

1134
00:52:10,600 --> 00:52:13,080
Speaker 3: the galaxy. And if you just sort of look at

1135
00:52:13,120 --> 00:52:15,480
Speaker 3: the velocity on average of all this stuff orbiting, that's

1136
00:52:15,520 --> 00:52:17,399
Speaker 3: what I mean by standing still. That's what we call

1137
00:52:17,440 --> 00:52:20,400
Speaker 3: the local standard of rest, and that's the orbit you

1138
00:52:20,400 --> 00:52:22,280
Speaker 3: would just expect stuff to take.

1139
00:52:22,080 --> 00:52:26,120
Speaker 5: If it hadn't been pushed around gravitationally by things. So

1140
00:52:26,200 --> 00:52:28,320
Speaker 5: gas tends to be in that kind of an orbit.

1141
00:52:28,520 --> 00:52:30,719
Speaker 3: The stars it forms tend to be in that kind

1142
00:52:30,760 --> 00:52:33,239
Speaker 3: of orbit, and this stuff that gets ejected from those

1143
00:52:33,280 --> 00:52:35,480
Speaker 3: young stars tend to be in that kind of an orbit.

1144
00:52:36,080 --> 00:52:37,280
Speaker 3: The Sun is over four.

1145
00:52:37,120 --> 00:52:37,960
Speaker 5: Billion years old.

1146
00:52:38,400 --> 00:52:40,879
Speaker 3: In those four and a half billion years, it's had

1147
00:52:40,880 --> 00:52:44,080
Speaker 3: close encounters with stars, It's gone by giant molecular clouds.

1148
00:52:44,080 --> 00:52:47,680
Speaker 3: It's gotten perturbed and bumped around, and now its orbit

1149
00:52:47,760 --> 00:52:49,440
Speaker 3: is kind of wonky. It kind of bobs up and

1150
00:52:49,480 --> 00:52:51,640
Speaker 3: down and in and out, and it has this velocity,

1151
00:52:52,360 --> 00:52:55,319
Speaker 3: and it's that velocity that we saw reflected back at

1152
00:52:55,400 --> 00:52:59,000
Speaker 3: us from Omuamua. So the story that makes sense, but

1153
00:52:59,040 --> 00:53:02,960
Speaker 3: again big Aerbars, is that a nearby cloud of gas

1154
00:53:03,360 --> 00:53:07,360
Speaker 3: formed a star millions of years ago in this special

1155
00:53:08,120 --> 00:53:10,439
Speaker 3: velocity frame, you know, in this kind of orbit around

1156
00:53:10,440 --> 00:53:14,960
Speaker 3: the galaxy, that star kicked out o'muamua. Omua has very

1157
00:53:14,960 --> 00:53:17,239
Speaker 3: low velocity with respect to that star because it just

1158
00:53:17,239 --> 00:53:19,960
Speaker 3: barely escaped and then whacked the sun came.

1159
00:53:19,760 --> 00:53:21,440
Speaker 5: And plowed right into it. So it all kind of

1160
00:53:21,440 --> 00:53:22,040
Speaker 5: hangs together.

1161
00:53:22,440 --> 00:53:25,680
Speaker 2: And this sort of more sensationalist view is that it's

1162
00:53:25,719 --> 00:53:28,080
Speaker 2: like a buoy. It's some sort of like it's at

1163
00:53:28,120 --> 00:53:30,600
Speaker 2: rest with respects of the galaxy to serve as like

1164
00:53:30,640 --> 00:53:33,040
Speaker 2: a navigational beacon or something.

1165
00:53:33,280 --> 00:53:37,439
Speaker 3: Right, And so Aby sees this special velocity and says,

1166
00:53:37,440 --> 00:53:39,360
Speaker 3: what are the odds that it would have that velocity?

1167
00:53:39,840 --> 00:53:41,560
Speaker 3: And we're like, well, you know, pretty good if it's

1168
00:53:41,560 --> 00:53:44,040
Speaker 3: a young object, because that's the velocity young objects has

1169
00:53:44,080 --> 00:53:46,680
Speaker 3: it's never mind, lots of things going different velocities, why

1170
00:53:46,719 --> 00:53:49,360
Speaker 3: would it be special. So then he dreams up a

1171
00:53:49,400 --> 00:53:53,319
Speaker 3: reason why aliens might want to put an object in

1172
00:53:53,440 --> 00:53:56,040
Speaker 3: that particular reference frame, and so he suggested it was

1173
00:53:56,120 --> 00:53:58,560
Speaker 3: like a booi, that it sits there for some purpose

1174
00:53:58,760 --> 00:54:01,279
Speaker 3: at that velocity. And then I guess the sun came

1175
00:54:01,320 --> 00:54:03,560
Speaker 3: along and knocked it out, and now it's, you know,

1176
00:54:03,680 --> 00:54:06,040
Speaker 3: headed off in some other direction. I mean, I guess

1177
00:54:06,040 --> 00:54:07,640
Speaker 3: I don't know why they would do that. It also

1178
00:54:07,680 --> 00:54:10,279
Speaker 3: doesn't seem consistent with it being a light sale. If

1179
00:54:10,320 --> 00:54:12,320
Speaker 3: it's just a discarded light sale, that's not a booi,

1180
00:54:12,400 --> 00:54:14,400
Speaker 3: that's just a piece of litter. Or maybe the thing

1181
00:54:14,440 --> 00:54:16,560
Speaker 3: that got launched was a booi, and it's I don't

1182
00:54:16,600 --> 00:54:19,319
Speaker 3: really understand anyway. You know, you can always dream up

1183
00:54:19,400 --> 00:54:24,360
Speaker 3: some reason aliens might make something have a particular character,

1184
00:54:24,680 --> 00:54:26,799
Speaker 3: but I'm not sure for Omua Mua. We have one

1185
00:54:26,880 --> 00:54:29,080
Speaker 3: story that explains all of these characters.

1186
00:54:29,360 --> 00:54:32,719
Speaker 2: So then to wrap up, Omumu is definitely an interesting object, right.

1187
00:54:33,000 --> 00:54:36,680
Speaker 2: It had a sort of unusual shape, maybe some unusual reflectivity.

1188
00:54:37,400 --> 00:54:41,400
Speaker 2: Fascinating acceleration tells us something maybe about the population of

1189
00:54:41,440 --> 00:54:44,239
Speaker 2: these things in our Solar System and in other solar systems,

1190
00:54:44,440 --> 00:54:47,359
Speaker 2: the velocity of stuff. But all in all, what is

1191
00:54:47,360 --> 00:54:50,000
Speaker 2: your best hypothesis? Is it that it's some chunk of

1192
00:54:50,160 --> 00:54:54,120
Speaker 2: nitrogen or hydrogen ice that the Sun basically plowed into.

1193
00:54:54,680 --> 00:54:57,880
Speaker 3: Yeah, So with the caveat that I'm not a planetary scientist,

1194
00:54:57,960 --> 00:55:00,120
Speaker 3: like I got into this because people were asking me,

1195
00:55:00,800 --> 00:55:04,200
Speaker 3: as the director of the Penn State Extraterrestrial Intelligence Center,

1196
00:55:04,239 --> 00:55:06,200
Speaker 3: what I thought of claims that it might be a spacecraft.

1197
00:55:06,800 --> 00:55:09,319
Speaker 3: And so in addressing those claims, you know, I had

1198
00:55:09,360 --> 00:55:12,160
Speaker 3: to learn from the planetary science community.

1199
00:55:12,080 --> 00:55:14,640
Speaker 5: What was weird about it, what wasn't weird about it?

1200
00:55:15,120 --> 00:55:18,560
Speaker 3: And so, you know, I worked with two planetary scientists,

1201
00:55:18,600 --> 00:55:21,719
Speaker 3: Sean Raymond and Steve Desh, who taught me a lot

1202
00:55:21,719 --> 00:55:24,080
Speaker 3: about these things and about what we do and don't

1203
00:55:24,080 --> 00:55:26,880
Speaker 3: know about Omuamua, And we thought about all of the.

1204
00:55:26,880 --> 00:55:28,680
Speaker 5: Different suggestions that have been made.

1205
00:55:29,160 --> 00:55:32,799
Speaker 3: So I basically reflect what they, as experts, tell me

1206
00:55:32,880 --> 00:55:35,439
Speaker 3: sounds most reasonable, and that is that it's a chunk

1207
00:55:35,440 --> 00:55:37,279
Speaker 3: of ice, that it's a comet that has some weird

1208
00:55:37,400 --> 00:55:40,760
Speaker 3: kind of ice, and that's really interesting. Steve's preferred hypothesis

1209
00:55:41,160 --> 00:55:43,839
Speaker 3: is that it's nitrogen ice, and he's worked really hard

1210
00:55:43,920 --> 00:55:45,799
Speaker 3: to show that that fits all the data very well

1211
00:55:45,840 --> 00:55:49,279
Speaker 3: and is a plausible substance other people like hydrogen. And

1212
00:55:49,360 --> 00:55:51,600
Speaker 3: you know, there also might be ideas that just we

1213
00:55:51,680 --> 00:55:53,560
Speaker 3: haven't come up with yet. It could be that when

1214
00:55:53,560 --> 00:55:55,760
Speaker 3: we finally get a close look at one of these things,

1215
00:55:55,760 --> 00:55:56,640
Speaker 3: we're surprised. You know.

1216
00:55:56,760 --> 00:55:59,239
Speaker 5: Oh, of course, that's why Omumama looked like that.

1217
00:55:59,440 --> 00:56:01,640
Speaker 2: Tell you talk about the sort of role of these

1218
00:56:01,719 --> 00:56:04,799
Speaker 2: crazy hypotheses in science. You know, Amy makes a lot

1219
00:56:04,800 --> 00:56:08,200
Speaker 2: of noise about being like Galileo. You know that his

1220
00:56:08,400 --> 00:56:11,040
Speaker 2: ideas aren't being taken seriously, et cetera. Tell me, do

1221
00:56:11,080 --> 00:56:14,799
Speaker 2: you think it's useful for us to entertain these crazy ideas?

1222
00:56:14,960 --> 00:56:16,799
Speaker 2: What do you think about is the comments he's made

1223
00:56:16,840 --> 00:56:19,040
Speaker 2: in public about this versus the comments he's made in

1224
00:56:19,120 --> 00:56:21,040
Speaker 2: sort of more academic settings.

1225
00:56:21,360 --> 00:56:25,080
Speaker 3: I think it's really important that we constantly challenge conventional wisdom,

1226
00:56:25,200 --> 00:56:27,840
Speaker 3: especially in areas where we have very little data, like

1227
00:56:27,960 --> 00:56:32,160
Speaker 3: small small objects around the Sun or interstellar comments. And

1228
00:56:32,440 --> 00:56:35,200
Speaker 3: I think it's very easy for us to feel like

1229
00:56:35,239 --> 00:56:39,040
Speaker 3: we've got everything figured out and then be blind when

1230
00:56:39,200 --> 00:56:41,520
Speaker 3: data showing us that we're wrong comes along.

1231
00:56:41,600 --> 00:56:42,359
Speaker 5: And rejecting it.

1232
00:56:42,440 --> 00:56:44,840
Speaker 3: It's like, oh, well, that's that's an extraordinary hypothesis that

1233
00:56:44,880 --> 00:56:45,720
Speaker 3: we could have been wrong.

1234
00:56:46,000 --> 00:56:46,200
Speaker 2: You know.

1235
00:56:46,719 --> 00:56:47,479
Speaker 5: But for the.

1236
00:56:47,360 --> 00:56:50,440
Speaker 3: Most part, I think scientists are really eager to be

1237
00:56:50,560 --> 00:56:53,480
Speaker 3: the one that makes that big surprising discovery. We tend

1238
00:56:53,520 --> 00:56:57,160
Speaker 3: to be very open minded about this stuff. And you know,

1239
00:56:57,280 --> 00:57:00,840
Speaker 3: when this started coming through, science fiction had already primed

1240
00:57:00,920 --> 00:57:03,120
Speaker 3: us to think it might be an alien spacecraft. You know,

1241
00:57:03,160 --> 00:57:06,279
Speaker 3: there's this story by Arthur Clark Rendezvous with Rama, and

1242
00:57:06,360 --> 00:57:08,520
Speaker 3: on Twitter. As soon as it, you know, was announced,

1243
00:57:08,520 --> 00:57:10,440
Speaker 3: we were joking like, oh, we've got to name it Rama.

1244
00:57:10,440 --> 00:57:13,160
Speaker 3: Maybe it's an alien spacecraft. Like, you know, this idea

1245
00:57:13,360 --> 00:57:17,000
Speaker 3: was out there. These kinds of challenges to our conventional

1246
00:57:17,040 --> 00:57:20,160
Speaker 3: thinking are important, and I think in general they are

1247
00:57:20,240 --> 00:57:25,720
Speaker 3: appreciated by most scientists, provided you know, the level of

1248
00:57:25,760 --> 00:57:29,200
Speaker 3: certainty that's being conveyed here is appropriate. You know, have

1249
00:57:29,360 --> 00:57:31,760
Speaker 3: we considered this, have we ruled it out? Could it

1250
00:57:31,800 --> 00:57:32,720
Speaker 3: be this is kind of weird?

1251
00:57:32,760 --> 00:57:35,400
Speaker 5: Wouldn't that be cool? You know, as long as.

1252
00:57:35,240 --> 00:57:38,320
Speaker 3: You're acknowledging the weight of evidence that it's not from

1253
00:57:38,360 --> 00:57:42,439
Speaker 3: prior experience, I think it's fine. Where I think Avi

1254
00:57:42,600 --> 00:57:46,400
Speaker 3: rankles a lot of people is by you know, claiming that,

1255
00:57:46,760 --> 00:57:49,440
Speaker 3: you know, his ideas are being shot down, you know,

1256
00:57:49,760 --> 00:57:53,720
Speaker 3: just because they're radical, and not because of the certainty.

1257
00:57:53,200 --> 00:57:55,640
Speaker 5: He's conveying to the public and how likely it is.

1258
00:57:55,680 --> 00:57:58,360
Speaker 3: I mean, he wrote wrote a whole book that you know,

1259
00:57:58,480 --> 00:58:01,440
Speaker 3: it hedges a little, it's little meally mouthed, but it's

1260
00:58:01,480 --> 00:58:04,040
Speaker 3: basically making the argument that it must.

1261
00:58:03,880 --> 00:58:05,560
Speaker 5: Be an alien spacecraft.

1262
00:58:05,960 --> 00:58:08,320
Speaker 3: And he makes statements in the media that you know,

1263
00:58:08,360 --> 00:58:11,560
Speaker 3: it really needs to be artificial, when that's not true

1264
00:58:11,560 --> 00:58:14,760
Speaker 3: at all. And that's when people really start getting you know,

1265
00:58:15,040 --> 00:58:18,200
Speaker 3: upset with a lot of obvious behavior. And then you know,

1266
00:58:18,240 --> 00:58:20,600
Speaker 3: when he comes back and says, we're just being closed

1267
00:58:20,600 --> 00:58:23,760
Speaker 3: minded and we're just this is just professional jealousy of

1268
00:58:23,840 --> 00:58:25,640
Speaker 3: all the attention he's getting.

1269
00:58:26,320 --> 00:58:29,000
Speaker 2: You know, that gets old really fast, right, You wrote

1270
00:58:29,040 --> 00:58:34,800
Speaker 2: in your essay quote Loeb's work is unambiguously counterproductive, alienating

1271
00:58:34,800 --> 00:58:38,000
Speaker 2: the community working on these problems and misinforming the public

1272
00:58:38,080 --> 00:58:40,720
Speaker 2: about the state of the field. And as somebody who

1273
00:58:40,760 --> 00:58:43,880
Speaker 2: works both in academia trying to understand the sort of

1274
00:58:43,920 --> 00:58:47,280
Speaker 2: the cutting edge knowledge and interfacing with the public, I'm

1275
00:58:47,280 --> 00:58:49,960
Speaker 2: definitely sensitive to this question of like how we present

1276
00:58:50,040 --> 00:58:52,240
Speaker 2: our work to the public with all of its nuances

1277
00:58:52,280 --> 00:58:54,720
Speaker 2: and caveats, and how that reflects the work being done

1278
00:58:54,760 --> 00:58:57,000
Speaker 2: sort of at the cutting edge. It's important to get

1279
00:58:57,000 --> 00:58:58,320
Speaker 2: that balance, right, I agree with.

1280
00:58:58,280 --> 00:59:01,160
Speaker 3: You, Yeah, And you know, to be clear, the problem

1281
00:59:01,280 --> 00:59:03,880
Speaker 3: isn't that he suggested it's an alien spacecraft, right, That's

1282
00:59:03,960 --> 00:59:08,480
Speaker 3: not counterproductive. That's fun, that's interesting. We should be wondering,

1283
00:59:08,640 --> 00:59:10,960
Speaker 3: just like Shrowsky did, if there we might be able

1284
00:59:11,000 --> 00:59:13,160
Speaker 3: to find alien spacecraft in the Solar System, that'd be

1285
00:59:13,240 --> 00:59:15,040
Speaker 3: very cool. So or at least we can show there

1286
00:59:15,040 --> 00:59:18,600
Speaker 3: aren't any. And you know, that's something people have studied

1287
00:59:18,600 --> 00:59:21,880
Speaker 3: and talked about and you know, is very appropriate. It's

1288
00:59:21,920 --> 00:59:24,720
Speaker 3: the you know, my objection is to the level of

1289
00:59:24,760 --> 00:59:27,760
Speaker 3: certainty that he projects on the fact that this is

1290
00:59:27,840 --> 00:59:30,600
Speaker 3: one to the public, but also the way that he

1291
00:59:30,720 --> 00:59:34,440
Speaker 3: dismisses expertise of people who have studied this stuff their

1292
00:59:34,480 --> 00:59:37,120
Speaker 3: whole careers and gets angry at them for contradicting him,

1293
00:59:37,280 --> 00:59:39,560
Speaker 3: and just tells people that they're wrong and closed minded

1294
00:59:39,600 --> 00:59:41,760
Speaker 3: and they don't know what they're talking about, even though they,

1295
00:59:42,560 --> 00:59:44,600
Speaker 3: you know, are the ones that have degrees in the

1296
00:59:44,600 --> 00:59:45,840
Speaker 3: field and have studied it for.

1297
00:59:45,800 --> 00:59:48,640
Speaker 5: Decades, you know, And he's just coming into it for the.

1298
00:59:48,640 --> 00:59:52,040
Speaker 2: First time, right, And of course every scientist would love

1299
00:59:52,240 --> 00:59:54,840
Speaker 2: if he was right, if we did discover aliens or

1300
00:59:54,840 --> 00:59:57,800
Speaker 2: a piece of alien junk, we'd all be jumping for joy.

1301
00:59:58,120 --> 01:00:00,320
Speaker 2: Something else you wrote in your essay quote, there is

1302
01:00:00,400 --> 01:00:04,440
Speaker 2: little joy for debunking claims in science. I think resonated

1303
01:00:04,480 --> 01:00:06,720
Speaker 2: with me also, because, yeah, we would love to make

1304
01:00:06,720 --> 01:00:08,880
Speaker 2: this discovery, but of course we got to be cautious

1305
01:00:08,880 --> 01:00:12,480
Speaker 2: and we got to be careful extraordinary claims and extraordinary evidence.

1306
01:00:12,520 --> 01:00:14,160
Speaker 2: As we've always said, yeah.

1307
01:00:13,920 --> 01:00:16,440
Speaker 3: That's right, and it really is no fun debunking claim

1308
01:00:16,520 --> 01:00:19,720
Speaker 3: In the early days of planet discovery, when I was

1309
01:00:19,760 --> 01:00:22,280
Speaker 3: a graduate student, there were lots you know, every time

1310
01:00:22,320 --> 01:00:23,880
Speaker 3: you found a planet, it was on the front page

1311
01:00:23,880 --> 01:00:25,920
Speaker 3: of the New York Times, and so there was a

1312
01:00:25,960 --> 01:00:28,920
Speaker 3: lot of incentive to fool yourself into thinking that some

1313
01:00:29,000 --> 01:00:31,600
Speaker 3: signal that you detected was a planet around another star.

1314
01:00:32,520 --> 01:00:34,440
Speaker 3: And so there were a lot of planes made that

1315
01:00:34,480 --> 01:00:37,400
Speaker 3: were clearly right, a lot that you know, a little iffy, and.

1316
01:00:37,360 --> 01:00:40,000
Speaker 5: Some that were just wishful thinking, unfortunately on the part

1317
01:00:40,040 --> 01:00:41,439
Speaker 5: of the astronomers that made them.

1318
01:00:41,520 --> 01:00:44,080
Speaker 3: And we were always torn, like do we stop the

1319
01:00:44,080 --> 01:00:47,120
Speaker 3: work we're doing finding these new planets to go and

1320
01:00:47,160 --> 01:00:49,120
Speaker 3: debunk this other claim and kind of clean up the

1321
01:00:49,200 --> 01:00:51,120
Speaker 3: masks and say no, no, that one turned out not

1322
01:00:51,200 --> 01:00:54,400
Speaker 3: to be right, because you know that's no fun. No

1323
01:00:54,440 --> 01:00:57,360
Speaker 3: one likes being the party pooper. You know that person

1324
01:00:57,400 --> 01:00:59,360
Speaker 3: isn't going to like you very much after you've done

1325
01:00:59,360 --> 01:01:03,080
Speaker 3: something like that. But also, we have better things to do, right,

1326
01:01:03,120 --> 01:01:05,160
Speaker 3: You have cool new planets to go find, and you

1327
01:01:05,200 --> 01:01:07,600
Speaker 3: only have so much time, and so it is frustrating,

1328
01:01:07,640 --> 01:01:09,960
Speaker 3: and you know it needs to be done. When claims

1329
01:01:10,040 --> 01:01:13,000
Speaker 3: reach a certain level of attention that you know someone

1330
01:01:13,040 --> 01:01:15,520
Speaker 3: needs to come in and sort of spell out, actually,

1331
01:01:15,800 --> 01:01:17,480
Speaker 3: you know what we really think about it.

1332
01:01:17,560 --> 01:01:19,440
Speaker 2: Well, thank you very much for taking the time to

1333
01:01:19,720 --> 01:01:21,800
Speaker 2: go through all these points and give us an understanding

1334
01:01:21,880 --> 01:01:24,040
Speaker 2: of what sort of the cutting edge science is on

1335
01:01:24,200 --> 01:01:26,520
Speaker 2: these questions. And thank you very much for talking to

1336
01:01:26,600 --> 01:01:28,320
Speaker 2: us today. Very helpful and a lot of fun to

1337
01:01:28,360 --> 01:01:30,720
Speaker 2: learn about this. What do you think the future holds

1338
01:01:30,840 --> 01:01:32,760
Speaker 2: for this field? Do you think we'll see more of

1339
01:01:32,800 --> 01:01:35,560
Speaker 2: these things come into our solar system and learn more

1340
01:01:35,600 --> 01:01:38,640
Speaker 2: about the sort of small dark objects in our own

1341
01:01:38,680 --> 01:01:40,320
Speaker 2: solar system and the rest of the galaxy.

1342
01:01:40,480 --> 01:01:41,280
Speaker 5: Yeah, I really do.

1343
01:01:41,440 --> 01:01:45,160
Speaker 3: The Reuben observatory is coming online in just a few years,

1344
01:01:45,560 --> 01:01:48,480
Speaker 3: and it's going to perform this gigantic survey. It's going

1345
01:01:48,520 --> 01:01:51,520
Speaker 3: to image the entire southern sky every three days basically,

1346
01:01:52,160 --> 01:01:56,000
Speaker 3: and it will have so much light collecting power and

1347
01:01:56,040 --> 01:01:58,040
Speaker 3: it will survey so much of the sky at once

1348
01:01:58,840 --> 01:02:03,840
Speaker 3: that it will probably find things like oh Muamo almost

1349
01:02:03,960 --> 01:02:06,760
Speaker 3: every year. And that means we'll have a lot of

1350
01:02:06,760 --> 01:02:08,680
Speaker 3: these to study, and we'll be able to catch some

1351
01:02:08,760 --> 01:02:10,600
Speaker 3: of them on the way into the Solar System and

1352
01:02:10,640 --> 01:02:12,680
Speaker 3: see how much mass they lose. We'll be able to

1353
01:02:12,680 --> 01:02:15,640
Speaker 3: see how many of them look like oh Muhamoa, you know,

1354
01:02:15,800 --> 01:02:19,160
Speaker 3: and try and you know, learn about their characteristics more generally.

1355
01:02:19,480 --> 01:02:23,080
Speaker 3: They're even plans, which I just find amazing and wonderful,

1356
01:02:23,640 --> 01:02:26,200
Speaker 3: to launch spacecraft to go catch one of them. Now

1357
01:02:26,200 --> 01:02:28,480
Speaker 3: they're moving too fast to actually just straight up catch,

1358
01:02:29,200 --> 01:02:31,800
Speaker 3: but you could launch something that sort of lurks in

1359
01:02:31,840 --> 01:02:34,360
Speaker 3: the Solar System and when an opportune one comes on

1360
01:02:34,400 --> 01:02:37,000
Speaker 3: that it could intercept, could fly in the way and

1361
01:02:37,080 --> 01:02:39,240
Speaker 3: intercept it and get close up pictures and maybe even

1362
01:02:39,240 --> 01:02:39,800
Speaker 3: get a sample.

1363
01:02:40,000 --> 01:02:42,680
Speaker 2: Wow, that would be awesome. And I do still, of course,

1364
01:02:42,760 --> 01:02:44,600
Speaker 2: have some hope that maybe one of them is a

1365
01:02:44,600 --> 01:02:47,280
Speaker 2: piece of alien space junk, and that would be an

1366
01:02:47,280 --> 01:02:48,160
Speaker 2: incredible discovery.

1367
01:02:48,200 --> 01:02:50,160
Speaker 5: That would be pretty cool that I'd be very excited

1368
01:02:50,200 --> 01:02:50,560
Speaker 5: about that.

1369
01:02:51,800 --> 01:02:53,840
Speaker 2: All right, Well, thanks again very much for coming on

1370
01:02:53,880 --> 01:02:54,600
Speaker 2: the program today.

1371
01:02:54,720 --> 01:02:56,080
Speaker 5: My pleasure. Thanks for having me.

1372
01:02:56,240 --> 01:02:58,160
Speaker 1: All Right, that was a great interview. It's kind of

1373
01:02:58,200 --> 01:03:01,120
Speaker 1: interesting that Jason's job it is also to look for

1374
01:03:01,160 --> 01:03:02,080
Speaker 1: extraterrestrial life.

1375
01:03:02,160 --> 01:03:04,600
Speaker 2: Yeah, he's not only interested in this stuff, and like

1376
01:03:04,720 --> 01:03:07,680
Speaker 2: many of us, he wants to discover aliens. Right, Nobody

1377
01:03:07,720 --> 01:03:10,640
Speaker 2: is out there debunking obvious claims because we don't want

1378
01:03:10,640 --> 01:03:13,600
Speaker 2: to believe in aliens. We all want to believe it.

1379
01:03:13,600 --> 01:03:16,480
Speaker 2: It would be the discovery of the millennium of history.

1380
01:03:16,520 --> 01:03:18,720
Speaker 2: But we also don't want to mislead the general public

1381
01:03:19,160 --> 01:03:21,800
Speaker 2: about something that was most likely just a chunk of ice.

1382
01:03:22,680 --> 01:03:25,080
Speaker 1: And so in general, Jason thinks that it could all

1383
01:03:25,080 --> 01:03:28,880
Speaker 1: be explained, all of the weird things about Omuama have

1384
01:03:29,200 --> 01:03:32,000
Speaker 1: a more non alien explanation.

1385
01:03:32,080 --> 01:03:34,840
Speaker 2: Yeah, Jason thinks that this is actually teaching us something

1386
01:03:34,920 --> 01:03:38,880
Speaker 2: about solar systems, that Omama may not be that unusual,

1387
01:03:39,000 --> 01:03:41,000
Speaker 2: and that there might be these chunks of ice out

1388
01:03:41,000 --> 01:03:43,520
Speaker 2: there in other solar systems and in ours. One of

1389
01:03:43,560 --> 01:03:45,160
Speaker 2: the big points in the book is that this thing

1390
01:03:45,200 --> 01:03:47,680
Speaker 2: looks different from the things in our solar system. But

1391
01:03:47,800 --> 01:03:49,919
Speaker 2: Jason points out that we're not great at seeing these

1392
01:03:49,960 --> 01:03:52,440
Speaker 2: things even in our solar systems. So it might be

1393
01:03:52,520 --> 01:03:55,280
Speaker 2: that there's a whole hidden ocean of these chunks of

1394
01:03:55,280 --> 01:03:57,800
Speaker 2: ice out there in our own or cloud we just

1395
01:03:57,840 --> 01:04:00,800
Speaker 2: didn't know about them, And so maybe Omumua's not that unusual.

1396
01:04:00,880 --> 01:04:03,200
Speaker 2: It's just sort of telling us something about the world

1397
01:04:03,320 --> 01:04:05,640
Speaker 2: out there and our own backyard.

1398
01:04:05,840 --> 01:04:08,480
Speaker 1: Have we seen anything like it since it's been now

1399
01:04:08,520 --> 01:04:09,600
Speaker 1: five years.

1400
01:04:09,280 --> 01:04:13,160
Speaker 2: Well, we have seen another interstellar object two Iborisov also

1401
01:04:13,240 --> 01:04:15,440
Speaker 2: came through our solar system a couple of years later,

1402
01:04:15,560 --> 01:04:19,200
Speaker 2: and people have started looking for Oma like objects in

1403
01:04:19,240 --> 01:04:21,720
Speaker 2: our solar system and they've seen a few. They've seen

1404
01:04:21,760 --> 01:04:25,760
Speaker 2: some dark comets, these things that have non gravitational acceleration

1405
01:04:25,880 --> 01:04:28,360
Speaker 2: without displaying any sort of tail or coma. So I

1406
01:04:28,360 --> 01:04:30,280
Speaker 2: think it really has cracked open the door for us

1407
01:04:30,360 --> 01:04:32,720
Speaker 2: understanding our own solar system a bit better.

1408
01:04:33,000 --> 01:04:34,919
Speaker 1: Or maybe the aliens are just sending us a bunch

1409
01:04:34,920 --> 01:04:38,760
Speaker 1: of messages, or maybe we're a popular tourist destination.

1410
01:04:38,680 --> 01:04:40,960
Speaker 2: Or maybe we're just a dumping ground for alien junk.

1411
01:04:41,080 --> 01:04:42,520
Speaker 1: No, but the junk left, didn't it.

1412
01:04:43,440 --> 01:04:46,120
Speaker 2: That's true. Yeah, maybe we're just a byway for alien

1413
01:04:46,200 --> 01:04:47,920
Speaker 2: junk towards the galactic dump.

1414
01:04:48,120 --> 01:04:50,160
Speaker 1: Well, I guess that would still be a pretty interesting

1415
01:04:50,200 --> 01:04:51,920
Speaker 1: discovery Alien junk mail.

1416
01:04:52,640 --> 01:04:55,560
Speaker 2: That would be awesome and I look forward to the day. Aliens.

1417
01:04:55,600 --> 01:04:56,880
Speaker 2: Please do send us your.

1418
01:04:56,840 --> 01:04:59,400
Speaker 1: Junk all right, Well, we hope you enjoyed that. Thanks

1419
01:04:59,400 --> 01:05:01,400
Speaker 1: for joining us, see you next time.

1420
01:05:09,400 --> 01:05:12,200
Speaker 2: Thanks for listening, and remember that Daniel and Jorge Explain

1421
01:05:12,240 --> 01:05:16,240
Speaker 2: the Universe is a production of iHeartRadio. For more podcasts

1422
01:05:16,240 --> 01:05:20,920
Speaker 2: from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever

1423
01:05:20,960 --> 01:05:22,680
Speaker 2: you listen to your favorite shows.