1
00:00:08,360 --> 00:00:12,480
Speaker 1: Hey, Daniel, do you remember the days before we had smartphones?

2
00:00:13,440 --> 00:00:15,920
Speaker 1: I try not to think about it too much. Well,

3
00:00:15,920 --> 00:00:19,000
Speaker 1: you can't live with that, Wikipedia do your fingertips? How

4
00:00:19,040 --> 00:00:21,160
Speaker 1: else would I seem like an expert on anything? But no,

5
00:00:21,320 --> 00:00:24,840
Speaker 1: mostly I couldn't live without the direction right. Yeah. Are

6
00:00:24,880 --> 00:00:26,640
Speaker 1: you the kind of driver that needs to check them

7
00:00:26,640 --> 00:00:29,120
Speaker 1: out every ten seconds? Oh? Yeah, that is me. I

8
00:00:29,200 --> 00:00:32,120
Speaker 1: like to know exactly where I am on the surface

9
00:00:32,159 --> 00:00:34,600
Speaker 1: of the air at all times. At all times, I

10
00:00:34,640 --> 00:00:37,600
Speaker 1: need constant updates to make sure I've not gone off. Well,

11
00:00:37,600 --> 00:00:40,320
Speaker 1: what are you gonna do when humans get out into space?

12
00:00:40,600 --> 00:00:42,760
Speaker 1: Are you gonna get around there? I'm just gonna wait

13
00:00:42,840 --> 00:00:46,320
Speaker 1: until there are enough cell towers or at least WiFi. Yeah,

14
00:00:46,920 --> 00:01:06,959
Speaker 1: basic human survival needs in space, air, food, and WiFi. Hi.

15
00:01:07,000 --> 00:01:10,360
Speaker 1: I'm Jorge. I'm a cartoonist and the creator of PhD comments. Hi.

16
00:01:10,480 --> 00:01:14,480
Speaker 1: I'm Daniel. I'm a particle physicist, and I plan to

17
00:01:14,520 --> 00:01:19,960
Speaker 1: be the one million person in space. One million there.

18
00:01:20,000 --> 00:01:21,800
Speaker 1: You know there are seven billion of those, so you

19
00:01:21,840 --> 00:01:24,440
Speaker 1: know you let's put it pretty far ahead in line. Yeah. Well,

20
00:01:24,440 --> 00:01:26,360
Speaker 1: I don't want to be the first person, or the

21
00:01:26,400 --> 00:01:29,160
Speaker 1: second person or the hundredth person, but I also don't

22
00:01:29,160 --> 00:01:30,440
Speaker 1: want to be the last person. You don't want to

23
00:01:30,440 --> 00:01:32,720
Speaker 1: go when it's still kind of new and fresh but

24
00:01:32,800 --> 00:01:35,160
Speaker 1: not dangerous. I'm not a test pilot kind of a person.

25
00:01:35,680 --> 00:01:38,200
Speaker 1: A million sounds about right. A million sounds about right,

26
00:01:38,240 --> 00:01:40,720
Speaker 1: but hey, I'm flexible two million, million and a half.

27
00:01:40,800 --> 00:01:42,240
Speaker 1: You know I'm not going to elbow my way in

28
00:01:42,280 --> 00:01:45,360
Speaker 1: that line. Well, welcome to our podcast where you are

29
00:01:45,440 --> 00:01:48,200
Speaker 1: first in line to hear this. It's called Daniel and

30
00:01:48,280 --> 00:01:51,040
Speaker 1: Jorge Explain the Universe, a production of I Heart Radio

31
00:01:51,120 --> 00:01:54,080
Speaker 1: where normally we take you on a mental trip around

32
00:01:54,160 --> 00:01:57,800
Speaker 1: the cosmos, zooming out from the tiniest little particles that

33
00:01:57,840 --> 00:02:00,600
Speaker 1: define the basic building blocks of the universe all the

34
00:02:00,600 --> 00:02:04,320
Speaker 1: way out to the grandest structures that shape the nature

35
00:02:04,320 --> 00:02:06,080
Speaker 1: of the cosmos itself. Yeah. I just think it was

36
00:02:06,160 --> 00:02:09,400
Speaker 1: as your guide, as your personal GPS to all of

37
00:02:09,400 --> 00:02:12,560
Speaker 1: the amazing and wonderful things that are in the universe

38
00:02:12,560 --> 00:02:15,000
Speaker 1: and also all of the unknown things that are out

39
00:02:15,000 --> 00:02:16,760
Speaker 1: there for us to discover. Do you think we're a

40
00:02:16,760 --> 00:02:19,320
Speaker 1: good mental GPS. Sometimes we get lost, We get on

41
00:02:19,360 --> 00:02:21,919
Speaker 1: a discussion about neutrinos and we end up talking about

42
00:02:21,919 --> 00:02:25,399
Speaker 1: snack foods. Well, you know, I think detours are part

43
00:02:25,400 --> 00:02:28,079
Speaker 1: of the fun of a trip. Right. I wish that

44
00:02:28,200 --> 00:02:30,679
Speaker 1: my navigation like Siri would tell me, like, hey, pull

45
00:02:30,720 --> 00:02:33,680
Speaker 1: over and get some chips. There's a good snack shop

46
00:02:33,800 --> 00:02:36,359
Speaker 1: right here. Why not? Yeah, that should be a setting, right,

47
00:02:37,360 --> 00:02:41,239
Speaker 1: suggests snacks. I like that suggests yeah, AI engineers, get

48
00:02:41,240 --> 00:02:43,400
Speaker 1: on it. Not in a hurry. Should be maybe an

49
00:02:43,400 --> 00:02:46,280
Speaker 1: option open to wonderful discovery. That's right. And on this

50
00:02:46,360 --> 00:02:48,960
Speaker 1: podcast we try to open your mind to all the

51
00:02:49,000 --> 00:02:52,240
Speaker 1: future wonderful discoveries that science will bring us. And we

52
00:02:52,280 --> 00:02:55,280
Speaker 1: do that by talking about the cutting edge of science,

53
00:02:55,560 --> 00:02:58,720
Speaker 1: all the questions that science has not answered, all the

54
00:02:58,720 --> 00:03:00,880
Speaker 1: things scientists are trying to think ground, and all the

55
00:03:00,919 --> 00:03:04,000
Speaker 1: technical problems they're trying to solve on their journey to

56
00:03:04,040 --> 00:03:06,440
Speaker 1: give us the answers. Yeah, because I think sometimes to

57
00:03:06,800 --> 00:03:09,760
Speaker 1: think about a journey of discovery is the journey itself,

58
00:03:10,080 --> 00:03:15,080
Speaker 1: you know, and the friends you make along the way. Yeah,

59
00:03:15,160 --> 00:03:16,480
Speaker 1: you know, not just where you go and what do

60
00:03:16,480 --> 00:03:18,560
Speaker 1: you find when you get there? For also how do

61
00:03:18,639 --> 00:03:20,639
Speaker 1: you get there and how do you how do you

62
00:03:20,639 --> 00:03:22,440
Speaker 1: even know where to go when you're going? Yeah, I

63
00:03:22,440 --> 00:03:25,680
Speaker 1: think people imagine that it's hard to get to Jupiter

64
00:03:26,040 --> 00:03:28,640
Speaker 1: or Pluto because it's so far out there. It's just

65
00:03:28,720 --> 00:03:31,640
Speaker 1: like you gotta throw a rock really far into space,

66
00:03:32,040 --> 00:03:35,360
Speaker 1: but it's not just really far away. It's like very

67
00:03:35,400 --> 00:03:38,160
Speaker 1: hard to find. You know. Pluto is a small rock

68
00:03:38,240 --> 00:03:41,720
Speaker 1: in the vast, vast reaches of space. If you're gonna

69
00:03:41,960 --> 00:03:44,720
Speaker 1: throw something in that direction, you have to be really precise.

70
00:03:44,800 --> 00:03:46,640
Speaker 1: You have to really know how to aim it and

71
00:03:46,680 --> 00:03:48,560
Speaker 1: have to be able to course correct along the way.

72
00:03:48,600 --> 00:03:51,040
Speaker 1: And that turns out to be not so easy. It's

73
00:03:51,120 --> 00:03:53,760
Speaker 1: much harder than stopping for snacks. Yeah, you know, they

74
00:03:53,760 --> 00:03:56,840
Speaker 1: have good snacks and jubiter. You know, it makes a

75
00:03:56,880 --> 00:03:59,160
Speaker 1: little gassy at the end, but you know it's all

76
00:03:59,280 --> 00:04:02,560
Speaker 1: totally worth it, right right the Red Storm chips. I

77
00:04:02,640 --> 00:04:05,440
Speaker 1: love this. Yeah. So today we're gonna be asking a

78
00:04:05,520 --> 00:04:08,160
Speaker 1: question that I personally have had a lot of curiosity

79
00:04:08,200 --> 00:04:10,760
Speaker 1: about over the years. I've always wondered about this question,

80
00:04:10,840 --> 00:04:13,440
Speaker 1: and even more so now recently I've been rewatching all

81
00:04:13,480 --> 00:04:16,240
Speaker 1: the Star Wars movies and so this is a question

82
00:04:16,240 --> 00:04:18,679
Speaker 1: that's really present in my mind that I've been asking

83
00:04:18,720 --> 00:04:21,520
Speaker 1: myself recently, And why is that? Are you imagining how

84
00:04:21,600 --> 00:04:24,000
Speaker 1: you're going to navigate to your in law's house on

85
00:04:24,040 --> 00:04:27,839
Speaker 1: the Jovian moons from your vacation place in Saturn or

86
00:04:27,920 --> 00:04:30,000
Speaker 1: what inspires you to think about this? Well, my wife

87
00:04:30,040 --> 00:04:31,800
Speaker 1: and I are immigrants, but we're not that that kind

88
00:04:31,800 --> 00:04:36,440
Speaker 1: of alien. But no, I just kind of wondered, you know, Um,

89
00:04:37,040 --> 00:04:39,479
Speaker 1: in Star Wars they always get lost or they pop

90
00:04:39,560 --> 00:04:41,479
Speaker 1: up in all kinds of places, and so how do

91
00:04:41,520 --> 00:04:43,960
Speaker 1: you know where you are? And how do you know

92
00:04:43,960 --> 00:04:45,560
Speaker 1: where to go? Or you know, they talk about like

93
00:04:45,600 --> 00:04:48,120
Speaker 1: a map of the galaxy, what does that even look like?

94
00:04:48,200 --> 00:04:50,240
Speaker 1: Or how would that even be useful? Yeah, it's it's

95
00:04:50,320 --> 00:04:52,880
Speaker 1: very rare that they're like, make a wrong turn. They're like,

96
00:04:53,040 --> 00:04:55,520
Speaker 1: we're we supposed to turn left at that pulsar or right.

97
00:04:55,560 --> 00:04:57,960
Speaker 1: I don't even really remember. It feels like that's all

98
00:04:58,000 --> 00:05:00,360
Speaker 1: just sort of been integrated into the electron next they

99
00:05:00,360 --> 00:05:02,800
Speaker 1: have in front of them. But those are hard problems, right,

100
00:05:02,839 --> 00:05:05,400
Speaker 1: it's not necessarily trivial to figure out. Yeah, and if

101
00:05:05,440 --> 00:05:07,600
Speaker 1: you think about it, in popular culture, there's only been

102
00:05:07,680 --> 00:05:11,520
Speaker 1: like one TV show about getting lost in space. You mean,

103
00:05:11,839 --> 00:05:15,080
Speaker 1: it was called space and you know at least you

104
00:05:15,120 --> 00:05:17,400
Speaker 1: know what it's about. Yeah, So today on the program,

105
00:05:17,440 --> 00:05:24,840
Speaker 1: we'll be asking the question, how do you navigate in

106
00:05:24,960 --> 00:05:28,760
Speaker 1: space space, and this is a problem that's relevant to

107
00:05:29,120 --> 00:05:32,719
Speaker 1: future navigation. Like imagine you are flying a spaceship with

108
00:05:32,800 --> 00:05:34,719
Speaker 1: lots of people on board and trying to get everybody

109
00:05:34,720 --> 00:05:38,039
Speaker 1: safely to Alpha Centauri. And it's also a question today

110
00:05:38,160 --> 00:05:41,120
Speaker 1: as NASA and the E s A launched satellites to

111
00:05:41,200 --> 00:05:43,600
Speaker 1: explore our Solar system. How do they make sure they

112
00:05:43,640 --> 00:05:45,839
Speaker 1: get to the right spot? How do they course correct

113
00:05:46,120 --> 00:05:48,760
Speaker 1: if they are off? Who does those calculations? Is that

114
00:05:48,880 --> 00:05:51,120
Speaker 1: on board the satellite or back here on Earth? Are

115
00:05:51,200 --> 00:05:55,240
Speaker 1: there people with protractors and pencils scribbling things furiously? How

116
00:05:55,279 --> 00:05:57,719
Speaker 1: does that actually work? Yeah, because you know, space is

117
00:05:57,760 --> 00:06:00,840
Speaker 1: pretty big, and it's three dementi all, you know, at

118
00:06:00,920 --> 00:06:04,120
Speaker 1: least three dimensions at least, yeah that we know of

119
00:06:05,240 --> 00:06:07,680
Speaker 1: that we think about right now. But it's a multi

120
00:06:07,680 --> 00:06:11,600
Speaker 1: dimensional and you're out there and you know, there's no

121
00:06:11,720 --> 00:06:15,839
Speaker 1: mountain to reference, no street signs. How do you get around?

122
00:06:15,839 --> 00:06:17,120
Speaker 1: How do you know where to go? Do you think

123
00:06:17,160 --> 00:06:18,880
Speaker 1: that third dimension is going to lead to like a

124
00:06:18,920 --> 00:06:21,719
Speaker 1: lot more marital arguments in the future, Like I told

125
00:06:21,720 --> 00:06:24,720
Speaker 1: you to turn up at that move man, why did

126
00:06:24,800 --> 00:06:26,920
Speaker 1: you turn down? This is just like so many more

127
00:06:26,920 --> 00:06:32,120
Speaker 1: ways to call new dimension to divorces. Probably no, but

128
00:06:32,160 --> 00:06:34,880
Speaker 1: it is really hard and it's also vital because you're

129
00:06:34,920 --> 00:06:39,000
Speaker 1: so much further away from your resources. Like these spaceships

130
00:06:39,120 --> 00:06:41,640
Speaker 1: they leave Earth, they're never getting a refill, like they

131
00:06:41,760 --> 00:06:44,280
Speaker 1: run out of gas because they got lost. They're just lost.

132
00:06:44,760 --> 00:06:47,279
Speaker 1: So you have like a very limited window to make

133
00:06:47,320 --> 00:06:50,040
Speaker 1: the moves you need to make to enter that orbit

134
00:06:50,160 --> 00:06:53,120
Speaker 1: or to fly by the moon. There's no reduce, like

135
00:06:53,200 --> 00:06:55,599
Speaker 1: you have a one tank and that's it. So it's

136
00:06:55,680 --> 00:06:58,720
Speaker 1: absolutely critical that you don't get lost and that you

137
00:06:58,760 --> 00:07:01,440
Speaker 1: figure out how to get where you need to go. Yeah, So,

138
00:07:01,480 --> 00:07:03,680
Speaker 1: as usually, we were wondering how many people out there

139
00:07:04,040 --> 00:07:06,279
Speaker 1: have thought about this question or even have an idea

140
00:07:06,279 --> 00:07:09,360
Speaker 1: about how to navigate in space. So as usual, Daniel

141
00:07:09,400 --> 00:07:12,120
Speaker 1: went out there and ask the internet to try to

142
00:07:12,160 --> 00:07:15,200
Speaker 1: answer this question, how do you navigate in space? That's right,

143
00:07:15,200 --> 00:07:18,320
Speaker 1: and if you'd like to participate in our virtual person

144
00:07:18,440 --> 00:07:21,040
Speaker 1: on the street interviews, just shoot us an email two

145
00:07:21,120 --> 00:07:23,960
Speaker 1: questions at Daniel and Jorge dot com. We would love

146
00:07:24,000 --> 00:07:26,640
Speaker 1: to put your uninformed speculation on the podcast. And so

147
00:07:26,680 --> 00:07:28,560
Speaker 1: think about it for a second. If you were out

148
00:07:28,640 --> 00:07:31,440
Speaker 1: in space in the middle of the galaxy or in

149
00:07:31,480 --> 00:07:34,320
Speaker 1: between galaxies? How would you know which way to make

150
00:07:34,320 --> 00:07:36,560
Speaker 1: your way home? Here's what people had to say. Because

151
00:07:36,600 --> 00:07:39,640
Speaker 1: gravity distill space and time and everything. Maybe you'd have

152
00:07:39,760 --> 00:07:42,240
Speaker 1: to go. Maybe you'd have to shoot a little bit

153
00:07:42,240 --> 00:07:45,920
Speaker 1: off it because as you as you go close to

154
00:07:46,040 --> 00:07:50,520
Speaker 1: and an object, you'd kind of be taken into its

155
00:07:50,680 --> 00:07:53,720
Speaker 1: gravitational swing. Other than that, I don't know how do

156
00:07:53,800 --> 00:07:56,760
Speaker 1: you navigate through deep space to just keep a set

157
00:07:56,760 --> 00:07:59,480
Speaker 1: of stars to your left and hopefully you're going the

158
00:07:59,520 --> 00:08:03,720
Speaker 1: same direct action. I have no idea. Maybe like by

159
00:08:03,760 --> 00:08:08,000
Speaker 1: distracting energy from the Sun, or if we're very patient,

160
00:08:08,040 --> 00:08:12,080
Speaker 1: maybe with solar sales, we could navigate deep space, maybe

161
00:08:12,200 --> 00:08:15,960
Speaker 1: through a pulse of a star, or like I don't know,

162
00:08:16,120 --> 00:08:18,760
Speaker 1: pole stars or something. I think the only way you

163
00:08:18,760 --> 00:08:20,880
Speaker 1: can navigating these spaces the way we do it now

164
00:08:20,920 --> 00:08:24,320
Speaker 1: by using stars and galaxies, things that are consistent, not

165
00:08:24,360 --> 00:08:27,720
Speaker 1: necessarily constellations, because that could you know, in three D

166
00:08:27,800 --> 00:08:30,440
Speaker 1: space they have depth and they have angles that they

167
00:08:30,440 --> 00:08:34,120
Speaker 1: are relative each other. You know, constellations do. But if

168
00:08:34,120 --> 00:08:36,760
Speaker 1: you use stuff like pulsars and quasars and you know

169
00:08:36,800 --> 00:08:40,160
Speaker 1: the Andromeda gag, see those things, we can coordinate ourselves

170
00:08:40,240 --> 00:08:42,520
Speaker 1: using a couple of those angles, we can coordinate ourselves

171
00:08:42,520 --> 00:08:45,040
Speaker 1: in deep space. I think navere taking in a deep

172
00:08:45,120 --> 00:08:49,400
Speaker 1: space or americum woulds to need the bicycles of navigation.

173
00:08:51,280 --> 00:08:55,440
Speaker 1: You're do either use inertial navigation, sitting time, speed, and

174
00:08:55,480 --> 00:08:57,760
Speaker 1: directions from someone In a short stuff you will have

175
00:08:57,880 --> 00:09:03,120
Speaker 1: to pick something like the sun and navigating reference to

176
00:09:03,160 --> 00:09:06,520
Speaker 1: the sun. Let's see, if you're heading to a prime centuri,

177
00:09:06,760 --> 00:09:09,559
Speaker 1: we should at least have an inbuilt special I had

178
00:09:09,559 --> 00:09:15,800
Speaker 1: invisible telescopes, I mean lens and meadows and special lists

179
00:09:16,360 --> 00:09:22,520
Speaker 1: and optimal path correction systems and some kind of special clocks.

180
00:09:23,480 --> 00:09:26,199
Speaker 1: Navigating in deep space, I would have to assume is

181
00:09:26,280 --> 00:09:29,280
Speaker 1: much like seiling the ocean. You look at the stars

182
00:09:29,360 --> 00:09:32,880
Speaker 1: and see whe're at relative to the stars. After your

183
00:09:34,000 --> 00:09:39,880
Speaker 1: statement that space is expanding faster than um the speed

184
00:09:39,880 --> 00:09:42,640
Speaker 1: of light, or faster than light can travel through it,

185
00:09:43,840 --> 00:09:49,040
Speaker 1: I really have no idea. Now I think you could

186
00:09:49,040 --> 00:09:53,880
Speaker 1: go anywhere you you go. Yeah, well, hopefully you can

187
00:09:53,880 --> 00:09:56,640
Speaker 1: do that, but how you do it? My idea would

188
00:09:56,679 --> 00:09:59,720
Speaker 1: be to mount a big giant telescope on the top

189
00:09:59,760 --> 00:10:03,080
Speaker 1: of your spacecraft, on the front and the back, so

190
00:10:03,160 --> 00:10:05,559
Speaker 1: you can see where you're going and where you're where

191
00:10:05,559 --> 00:10:07,800
Speaker 1: you came from. Maybe a telescope as big as hubble,

192
00:10:07,840 --> 00:10:09,920
Speaker 1: because your spacecraft is going to have to be that big.

193
00:10:10,000 --> 00:10:14,160
Speaker 1: After we leave the planet and learn about the like

194
00:10:14,320 --> 00:10:17,880
Speaker 1: further stars that we don't see on Earth, we can

195
00:10:17,960 --> 00:10:21,160
Speaker 1: pick three stars, and by keeping track of the distance

196
00:10:21,280 --> 00:10:24,920
Speaker 1: between us and the stars, we can know our position.

197
00:10:25,640 --> 00:10:29,360
Speaker 1: And when the stars are too far away, we can

198
00:10:29,440 --> 00:10:34,320
Speaker 1: always peak three new stars that we found out about

199
00:10:35,080 --> 00:10:37,600
Speaker 1: along the way in our journey. So there are a

200
00:10:37,600 --> 00:10:39,079
Speaker 1: lot of ideas there. What do you think of that?

201
00:10:39,320 --> 00:10:41,560
Speaker 1: Pretty good? Pretty good? I feel like people were sort

202
00:10:41,559 --> 00:10:45,240
Speaker 1: of thinking about triangulation and using the stars somehow to

203
00:10:45,480 --> 00:10:47,240
Speaker 1: tell where you are. I feel like that's a pretty

204
00:10:47,240 --> 00:10:50,920
Speaker 1: common idea in science fiction movies and boots. It's like, oh,

205
00:10:50,960 --> 00:10:53,360
Speaker 1: you just look at the stars around you, and do

206
00:10:53,400 --> 00:10:54,960
Speaker 1: you know where you are and you know where to go?

207
00:10:55,160 --> 00:10:56,640
Speaker 1: Or like if you look at the stars and you

208
00:10:56,679 --> 00:10:59,520
Speaker 1: don't recognize things, then you're kind of in trouble. I

209
00:10:59,600 --> 00:11:01,800
Speaker 1: like the I said, let's put a huge telescope on

210
00:11:01,840 --> 00:11:03,880
Speaker 1: the front and on the back of your spaceship, because

211
00:11:04,480 --> 00:11:06,720
Speaker 1: I want that anyway, Like, if I'm flying through space,

212
00:11:06,760 --> 00:11:08,520
Speaker 1: I want a big telescope because I want to see

213
00:11:08,520 --> 00:11:10,120
Speaker 1: with what stuffed around me. You know, I want to

214
00:11:10,160 --> 00:11:12,240
Speaker 1: do some sight seeing when I'm out there. But what

215
00:11:12,360 --> 00:11:13,960
Speaker 1: do you need one in the bag though, just to

216
00:11:14,040 --> 00:11:18,120
Speaker 1: see the fit is of people that you leave behind. Well,

217
00:11:18,160 --> 00:11:20,840
Speaker 1: because I mean, I guess you could turn your telescope.

218
00:11:20,840 --> 00:11:23,600
Speaker 1: Maybe you're saying you'll need one telescope plus like a

219
00:11:23,640 --> 00:11:27,160
Speaker 1: mount or something, but hey, more telescopes are better. Well,

220
00:11:27,200 --> 00:11:29,120
Speaker 1: I feel like that is a sort of a common thing,

221
00:11:29,200 --> 00:11:31,120
Speaker 1: is to look at the stars around you, and somehow

222
00:11:31,120 --> 00:11:32,839
Speaker 1: you use that to orient yourself, you know, kind of

223
00:11:32,880 --> 00:11:35,400
Speaker 1: like we use the North Star for a long time

224
00:11:35,440 --> 00:11:37,439
Speaker 1: to kind of tell which way was north when you're

225
00:11:37,440 --> 00:11:39,559
Speaker 1: out in the middle of the ocean. Is that kind

226
00:11:39,600 --> 00:11:41,600
Speaker 1: of an idea that we can use at all? It

227
00:11:41,720 --> 00:11:43,280
Speaker 1: is an idea that we can use. And the rest

228
00:11:43,320 --> 00:11:45,480
Speaker 1: on this notion that if you have an accurate map

229
00:11:45,600 --> 00:11:48,040
Speaker 1: of the stars, you can compare that to what you're

230
00:11:48,080 --> 00:11:51,880
Speaker 1: seeing and look for landmarks and try to measure angles

231
00:11:51,920 --> 00:11:54,040
Speaker 1: between the stars to give you a sense for where

232
00:11:54,080 --> 00:11:57,600
Speaker 1: you are. For example, if two stars are almost lined

233
00:11:57,679 --> 00:11:59,920
Speaker 1: up in your vision, then that tells you that you're

234
00:12:00,040 --> 00:12:03,200
Speaker 1: along a line drawn between those two stars. And if

235
00:12:03,240 --> 00:12:07,240
Speaker 1: you can find other examples measuring angles between stars, you

236
00:12:07,240 --> 00:12:09,240
Speaker 1: can give you sort of a point in three D

237
00:12:09,400 --> 00:12:11,880
Speaker 1: space for where you are at that moment. Well, I

238
00:12:12,080 --> 00:12:14,080
Speaker 1: guess the problem that I have always should have thought

239
00:12:14,120 --> 00:12:15,920
Speaker 1: about is like, what if you find yourself on the

240
00:12:15,960 --> 00:12:18,439
Speaker 1: other side of the galaxy, how would you even recognize

241
00:12:18,520 --> 00:12:20,640
Speaker 1: any of the stars because the stars are gonna look

242
00:12:20,679 --> 00:12:23,480
Speaker 1: totally different from the other side of the galaxy. Yeah,

243
00:12:23,480 --> 00:12:25,880
Speaker 1: if you just look at like teleported to a random

244
00:12:25,920 --> 00:12:28,760
Speaker 1: place in the universe where you have no reference points,

245
00:12:28,960 --> 00:12:31,840
Speaker 1: there's literally no way to know where you are because

246
00:12:31,960 --> 00:12:35,200
Speaker 1: there's no absolute reference there's no like point in space

247
00:12:35,240 --> 00:12:38,560
Speaker 1: that's defined in zero and you can measure your location

248
00:12:38,640 --> 00:12:41,560
Speaker 1: relative to that. If you get teleported to an arbitrary

249
00:12:41,600 --> 00:12:44,880
Speaker 1: point in space, special relativity says it's impossible to know

250
00:12:44,920 --> 00:12:48,080
Speaker 1: where you are. You can only measure your distance relative

251
00:12:48,120 --> 00:12:50,280
Speaker 1: to other stuff. So if you have no familiar references,

252
00:12:50,520 --> 00:12:53,760
Speaker 1: you're totally screwed. Wow, and things are like changing in time. Also,

253
00:12:53,920 --> 00:12:56,720
Speaker 1: everything's moving, so you're sort of totally lost in You're

254
00:12:56,760 --> 00:12:59,280
Speaker 1: totally lost. You have. The only way to orient yourself

255
00:12:59,320 --> 00:13:02,440
Speaker 1: in space is relative to known things. So if you

256
00:13:02,480 --> 00:13:05,640
Speaker 1: get teleported to some part of space that's totally unfamiliar.

257
00:13:06,040 --> 00:13:08,800
Speaker 1: Then you literally have no way to find your way

258
00:13:08,800 --> 00:13:12,400
Speaker 1: back except for randomly exploring until you do find a landmark.

259
00:13:12,760 --> 00:13:14,079
Speaker 1: And when I try that the next time I get

260
00:13:14,120 --> 00:13:17,960
Speaker 1: lost and my spouse is complaining, I'm like, it's special relativity.

261
00:13:18,160 --> 00:13:20,680
Speaker 1: It's it's law of the universe. It's not my fault.

262
00:13:20,840 --> 00:13:24,079
Speaker 1: Daniel said, this should work. Don't you feel like smartphones

263
00:13:24,160 --> 00:13:27,720
Speaker 1: must have solved this marital complaint? Right, houses don't have

264
00:13:27,720 --> 00:13:29,720
Speaker 1: to argue about how to navigating anymore, and they just

265
00:13:29,840 --> 00:13:32,600
Speaker 1: listened to the phone. That's right. The phone has saved

266
00:13:32,600 --> 00:13:35,680
Speaker 1: a lot of marriages. Probably maybe, or maybe people are like, no,

267
00:13:35,800 --> 00:13:38,439
Speaker 1: listen to my phone. Well, my phone says it's faster

268
00:13:38,520 --> 00:13:43,400
Speaker 1: take the expressway using Google Maps. No way, we aren't

269
00:13:43,480 --> 00:13:46,760
Speaker 1: using ways. People who argue are going to argue anyway.

270
00:13:46,880 --> 00:13:50,080
Speaker 1: I guess, So I guess the phones can't fix that. Yeah,

271
00:13:50,120 --> 00:13:53,920
Speaker 1: And you know, navigators in throughout history have used the stars.

272
00:13:53,960 --> 00:13:56,360
Speaker 1: Like if you have sailed the oceans, then to figure

273
00:13:56,360 --> 00:13:59,120
Speaker 1: out where you are in this vast sea where you

274
00:13:59,160 --> 00:14:01,480
Speaker 1: can see no land marks is just to look up

275
00:14:01,600 --> 00:14:04,440
Speaker 1: and look for star marks. Right, to look for the

276
00:14:04,440 --> 00:14:06,520
Speaker 1: positions of stars in the sky that gives you a

277
00:14:06,520 --> 00:14:08,640
Speaker 1: sense for where you might be. All right, well, let's

278
00:14:08,640 --> 00:14:11,120
Speaker 1: get into the sort of the nitty gritty of this problem.

279
00:14:11,280 --> 00:14:13,000
Speaker 1: And because I know you, you've told me that there

280
00:14:13,040 --> 00:14:16,200
Speaker 1: are sort of several ways in which we can right

281
00:14:16,200 --> 00:14:18,480
Speaker 1: now sort of calculate where we are in space, you know,

282
00:14:18,559 --> 00:14:22,440
Speaker 1: barring kind of like a complete map of the entire galaxy. Um,

283
00:14:22,440 --> 00:14:24,320
Speaker 1: so step us through. What's the what's the sort of

284
00:14:24,360 --> 00:14:26,760
Speaker 1: the basic way that we get around in space. So

285
00:14:26,800 --> 00:14:29,200
Speaker 1: the simplest way, in the dumbest way, and the worst

286
00:14:29,280 --> 00:14:33,080
Speaker 1: way is basically dead reckoning. And that says you know

287
00:14:33,160 --> 00:14:36,000
Speaker 1: where you started, and you started on Earth, and if

288
00:14:36,000 --> 00:14:38,320
Speaker 1: you have a record of all the moves you took,

289
00:14:38,520 --> 00:14:41,080
Speaker 1: you went in this direction at this velocity, you should

290
00:14:41,080 --> 00:14:43,680
Speaker 1: be able to calculate where you went. Because you know,

291
00:14:43,800 --> 00:14:46,840
Speaker 1: spacecraft follow the laws of physics, and we know what

292
00:14:46,920 --> 00:14:49,400
Speaker 1: those laws are. We have a whole model of the

293
00:14:49,440 --> 00:14:52,360
Speaker 1: Solar System, so we should be able to predict if

294
00:14:52,400 --> 00:14:55,120
Speaker 1: you leave in this direction at this time, and you

295
00:14:55,200 --> 00:14:57,640
Speaker 1: fire your rockets here and there, we should be able

296
00:14:57,640 --> 00:14:59,880
Speaker 1: to predict where you end up. That's kind of like

297
00:15:00,040 --> 00:15:03,320
Speaker 1: closing your eyes and like knowing where you are right now,

298
00:15:03,360 --> 00:15:05,880
Speaker 1: closing your eyes and just by like counting your steps

299
00:15:06,280 --> 00:15:08,680
Speaker 1: and how you think you turn, sort of like making

300
00:15:08,720 --> 00:15:10,360
Speaker 1: it to your fridge or something like that. It's like

301
00:15:10,360 --> 00:15:13,200
Speaker 1: following one of those treasure maps, like fifteen paces forward

302
00:15:13,440 --> 00:15:17,080
Speaker 1: then turn left step four paces, then dig right right.

303
00:15:17,360 --> 00:15:19,640
Speaker 1: And that's a little terrifying. Like if you remember the

304
00:15:19,720 --> 00:15:22,960
Speaker 1: days before smartphones where people had to like actually write

305
00:15:22,960 --> 00:15:26,080
Speaker 1: down directions and there were things like drive for fifteen

306
00:15:26,080 --> 00:15:28,600
Speaker 1: miles then take a left right, and you had no

307
00:15:28,680 --> 00:15:32,360
Speaker 1: idea is this the correct left or not? You know, yeah, yeah,

308
00:15:32,400 --> 00:15:33,640
Speaker 1: and we all know how well that works. In the

309
00:15:33,680 --> 00:15:34,760
Speaker 1: middle of the night when you have to go to

310
00:15:34,800 --> 00:15:39,320
Speaker 1: the bathroom in total darkness, you know, you better put

311
00:15:39,320 --> 00:15:41,080
Speaker 1: your hands in front of you, just in cakes. Yeah,

312
00:15:41,120 --> 00:15:44,120
Speaker 1: and so sailors used to call this dead reckoning, and

313
00:15:44,200 --> 00:15:47,040
Speaker 1: you know it's not terrible, like it works. Okay, we

314
00:15:47,120 --> 00:15:49,640
Speaker 1: have a pretty good model of the solar system, and

315
00:15:49,920 --> 00:15:52,000
Speaker 1: we have rockets, and we can even measure we don't

316
00:15:52,040 --> 00:15:54,440
Speaker 1: even have to just guess. And like the effect of thrust,

317
00:15:54,480 --> 00:15:59,080
Speaker 1: you can measure how much you've accelerated using accelerometers, you

318
00:15:59,120 --> 00:16:01,440
Speaker 1: can measure your the direction that you ended up in

319
00:16:01,560 --> 00:16:05,280
Speaker 1: using gyroscopes, So we've tried to be really careful about this,

320
00:16:05,320 --> 00:16:08,280
Speaker 1: and some spacecraft in the history of you know, American

321
00:16:08,360 --> 00:16:11,920
Speaker 1: exploration have used dead reckoning. But I guess it's tricky too,

322
00:16:11,960 --> 00:16:15,240
Speaker 1: because you know, in space you can't count your steps,

323
00:16:15,280 --> 00:16:17,280
Speaker 1: like there's nothing to hold onto to tell you how

324
00:16:17,320 --> 00:16:20,000
Speaker 1: far you move. You have to you have to measure

325
00:16:20,040 --> 00:16:24,240
Speaker 1: your exploration and then integrate DAD to convert to velocity,

326
00:16:24,280 --> 00:16:26,880
Speaker 1: and then integrate DAT to convert it to distance. So

327
00:16:26,960 --> 00:16:29,680
Speaker 1: it's like a lot of room there to get error. Yes,

328
00:16:29,680 --> 00:16:33,000
Speaker 1: and you mentioned a very critical step there, which is integration,

329
00:16:33,080 --> 00:16:36,280
Speaker 1: and that requires knowing the time. You can't count your steps.

330
00:16:36,440 --> 00:16:39,360
Speaker 1: What you need is a very accurate clock. And the

331
00:16:39,400 --> 00:16:42,080
Speaker 1: more accurate your clock, the more you accurately you can

332
00:16:42,080 --> 00:16:45,240
Speaker 1: calculate how far you've gone. Right, you said I shot

333
00:16:45,240 --> 00:16:47,280
Speaker 1: off in this direction of the speed, Well did you

334
00:16:47,280 --> 00:16:50,240
Speaker 1: go for two point seven seconds or two point eight seconds?

335
00:16:50,400 --> 00:16:53,600
Speaker 1: When you're traveling at ten thousand kilometers per second, that

336
00:16:53,680 --> 00:16:57,640
Speaker 1: makes a big difference. Yeah, And when distances are so huge, right,

337
00:16:57,920 --> 00:17:00,480
Speaker 1: and the stakes are so high, like you can't if

338
00:17:00,480 --> 00:17:02,600
Speaker 1: you miss Jupiter by a few miles, it could be

339
00:17:02,640 --> 00:17:05,520
Speaker 1: bad us. Yeah, as you're gonna do a Jupiter drive by, right,

340
00:17:05,840 --> 00:17:08,480
Speaker 1: then you only get one shot at it, literally, and

341
00:17:08,560 --> 00:17:11,000
Speaker 1: so it's pretty tricky. And the problem here is that

342
00:17:11,200 --> 00:17:13,840
Speaker 1: errors build up, Like you make a little mistake because

343
00:17:13,880 --> 00:17:16,520
Speaker 1: you turned a little too far, then you're off, and

344
00:17:16,520 --> 00:17:18,560
Speaker 1: the next time you can't correct it, and so the

345
00:17:18,680 --> 00:17:21,199
Speaker 1: errors just build up in the integrate and eventually you

346
00:17:21,200 --> 00:17:23,520
Speaker 1: can be pretty far from where you thought you right.

347
00:17:23,600 --> 00:17:27,119
Speaker 1: It literally is like walking around with your eyes closed. Yeah, exactly.

348
00:17:27,280 --> 00:17:30,640
Speaker 1: So that's the most basic strategy, and you can make

349
00:17:30,680 --> 00:17:33,640
Speaker 1: that more sophisticated by doing corrections. You can say, well,

350
00:17:33,840 --> 00:17:37,040
Speaker 1: I'm gonna use dead reckoning. Plus I'm going to look

351
00:17:37,040 --> 00:17:39,000
Speaker 1: at the stars and I'm gonna try to figure out

352
00:17:39,160 --> 00:17:41,359
Speaker 1: if I'm off. And this is what like a lot

353
00:17:41,400 --> 00:17:44,400
Speaker 1: of astronauts did, like Apollo eleven and follow their team.

354
00:17:44,560 --> 00:17:48,080
Speaker 1: They flew to the Moon by dead reckoning, but occasionally

355
00:17:48,119 --> 00:17:50,000
Speaker 1: they would check in and they would look at the

356
00:17:50,040 --> 00:17:52,560
Speaker 1: stars and try to get a more precise measurement for

357
00:17:52,600 --> 00:17:54,400
Speaker 1: where they were, and they would use that to correct

358
00:17:54,600 --> 00:17:57,720
Speaker 1: their flight path. Really, so I guess two questions. One

359
00:17:57,840 --> 00:18:00,480
Speaker 1: is why didn't they just use the moon as reference

360
00:18:00,800 --> 00:18:03,480
Speaker 1: because they were flying towards it, and they could tell

361
00:18:03,480 --> 00:18:06,399
Speaker 1: her they were going away from it or towards it.

362
00:18:06,560 --> 00:18:08,159
Speaker 1: And the size of it too, wouldn't it tell you

363
00:18:08,160 --> 00:18:10,399
Speaker 1: said of the distance? But and then my second question was,

364
00:18:11,000 --> 00:18:13,280
Speaker 1: you know, can you actually use the stars to tell

365
00:18:13,280 --> 00:18:16,280
Speaker 1: where you are? You can? So, yes, they were pointed

366
00:18:16,280 --> 00:18:18,320
Speaker 1: at the moon. But that's pretty rough, right, And what

367
00:18:18,359 --> 00:18:20,240
Speaker 1: you want to do was get to the Moon and

368
00:18:20,240 --> 00:18:22,879
Speaker 1: then enter into orbit around the Moon. And that was

369
00:18:22,880 --> 00:18:26,400
Speaker 1: a very precise maneuver. And just like with the spacecraft,

370
00:18:26,440 --> 00:18:28,400
Speaker 1: they had a limited amount of fuel, so if they

371
00:18:28,440 --> 00:18:30,480
Speaker 1: burnt their fuel the wrong time, they might not be

372
00:18:30,520 --> 00:18:32,680
Speaker 1: able to make it home. I said. The fuel is

373
00:18:32,760 --> 00:18:34,880
Speaker 1: very expensive to lift off the surface of the Earth,

374
00:18:34,960 --> 00:18:37,600
Speaker 1: and so everything was a very tight budget, so they

375
00:18:37,600 --> 00:18:41,240
Speaker 1: had to be really precise. There are no exactly you

376
00:18:41,280 --> 00:18:43,639
Speaker 1: can't just pull a eui in space. That costs a

377
00:18:43,680 --> 00:18:45,879
Speaker 1: lot of energy to pull ui. Like you missed the

378
00:18:45,920 --> 00:18:48,320
Speaker 1: snack shop. You missed the snack shop, man, you are

379
00:18:48,359 --> 00:18:51,280
Speaker 1: not going back. And yes, they did stellar navigation. They

380
00:18:51,359 --> 00:18:54,520
Speaker 1: looked by I to find stars, and they measured the

381
00:18:54,560 --> 00:18:58,920
Speaker 1: declination using gyroscopes and they use that to correct their calculations.

382
00:18:58,960 --> 00:19:01,240
Speaker 1: A huge fraction of the time they actually spent in

383
00:19:01,280 --> 00:19:05,359
Speaker 1: that module was typing data into that computer. You know,

384
00:19:05,480 --> 00:19:08,320
Speaker 1: it's a complicated system. And remember the whole program was

385
00:19:08,400 --> 00:19:11,320
Speaker 1: loaded into the computer before it launched, Like you didn't

386
00:19:11,359 --> 00:19:13,800
Speaker 1: have guys up there, like you know, tip tapping editing

387
00:19:13,800 --> 00:19:16,119
Speaker 1: the program being like I think we must change the

388
00:19:16,160 --> 00:19:18,639
Speaker 1: flight path or something. They had it all built in

389
00:19:18,840 --> 00:19:22,000
Speaker 1: with the opportunity for small corrections based on looking at

390
00:19:22,000 --> 00:19:24,640
Speaker 1: those stars. So what do you mean declination like where

391
00:19:24,680 --> 00:19:27,520
Speaker 1: the constellation was relative to the Earth or something like that. No,

392
00:19:27,680 --> 00:19:30,240
Speaker 1: relative to them, Right, they had an idea for where

393
00:19:30,240 --> 00:19:32,159
Speaker 1: they were, and they had an idea for if we

394
00:19:32,240 --> 00:19:35,440
Speaker 1: are here, the stars should appear at this angle relative

395
00:19:35,480 --> 00:19:38,200
Speaker 1: to the spaceship, and then they would measure where is

396
00:19:38,240 --> 00:19:41,240
Speaker 1: the star relative to where the spaceship is pointing because

397
00:19:41,240 --> 00:19:45,120
Speaker 1: I had careful gyroscopes and and those angles helped them

398
00:19:45,119 --> 00:19:48,320
Speaker 1: figure out exactly where they are. All right, Well that

399
00:19:48,359 --> 00:19:50,720
Speaker 1: sounds like, um it worked because they got to the

400
00:19:51,840 --> 00:19:55,359
Speaker 1: a few times, So I can't argue with that. All right, Well,

401
00:19:55,440 --> 00:19:57,320
Speaker 1: let's get into some of the other ways that we

402
00:19:57,400 --> 00:20:01,160
Speaker 1: can navigate in space and whether or not they could

403
00:20:01,160 --> 00:20:05,120
Speaker 1: help us explore the furthest switches of the Cosmos but first,

404
00:20:05,160 --> 00:20:19,879
Speaker 1: let's take a quick break, all right, Dina. We're talking

405
00:20:19,920 --> 00:20:24,520
Speaker 1: about navigating in space. Space, space, space, And I just

406
00:20:24,520 --> 00:20:27,200
Speaker 1: wonder why there's always an echo when people talk about space,

407
00:20:27,240 --> 00:20:30,760
Speaker 1: because there's no echoes in space. It's because it's cool, man,

408
00:20:31,240 --> 00:20:35,359
Speaker 1: It's so cool cool. It makes it sound mysterious. It

409
00:20:35,400 --> 00:20:38,640
Speaker 1: gives you a sense of literally space, right, echoes give

410
00:20:38,680 --> 00:20:40,960
Speaker 1: you a sense a big emptiness. But you know that's

411
00:20:40,960 --> 00:20:45,280
Speaker 1: just the um audio version of the artistic impression, which

412
00:20:45,359 --> 00:20:46,680
Speaker 1: you know, I'm not a fan. You not a fan

413
00:20:46,720 --> 00:20:50,040
Speaker 1: of the echoes in space. No, I'm a fan of

414
00:20:50,080 --> 00:20:52,720
Speaker 1: realistic science fiction. It should give us a cent or

415
00:20:52,800 --> 00:20:55,280
Speaker 1: what it's actually like to be out there. Though maybe

416
00:20:55,320 --> 00:20:57,240
Speaker 1: you know, if you're in a kind of little metal box,

417
00:20:57,280 --> 00:20:59,800
Speaker 1: maybe there are actually a lot of echoes, but inside

418
00:21:00,040 --> 00:21:03,280
Speaker 1: I see. Well, we're talking about how to navigating space,

419
00:21:03,359 --> 00:21:05,879
Speaker 1: which is a big question, you know. I feel like,

420
00:21:06,280 --> 00:21:08,080
Speaker 1: you know, whenever you watch a movie like Star Wars,

421
00:21:08,119 --> 00:21:09,679
Speaker 1: it's like how are they getting around? How do they

422
00:21:09,680 --> 00:21:11,320
Speaker 1: know where to go? And so we talked about it

423
00:21:11,440 --> 00:21:13,199
Speaker 1: one way, which is dead reckoning, Like if you know

424
00:21:13,240 --> 00:21:15,360
Speaker 1: you're an Earth and you leave Earth, you can sort

425
00:21:15,359 --> 00:21:17,600
Speaker 1: of track your progress, but then you also have to

426
00:21:17,680 --> 00:21:19,719
Speaker 1: kind of correct your errors as you go. That's right,

427
00:21:19,760 --> 00:21:22,320
Speaker 1: and a better way to do that is not just

428
00:21:22,440 --> 00:21:24,960
Speaker 1: be based on your initial calculation from Earth, but it

429
00:21:25,000 --> 00:21:29,080
Speaker 1: takes inspiration from how your smartphone gets you to your

430
00:21:29,080 --> 00:21:32,840
Speaker 1: friend's house, which is that it gets messages from satellites.

431
00:21:33,240 --> 00:21:35,919
Speaker 1: Here on Earth, we have the GPS system, which is

432
00:21:36,200 --> 00:21:40,159
Speaker 1: constantly broadcasting messages. That's giving your phone an idea for

433
00:21:40,240 --> 00:21:43,240
Speaker 1: where it is, and your phone figures out where it

434
00:21:43,320 --> 00:21:45,760
Speaker 1: is by hearing these messages and knowing how long it

435
00:21:45,800 --> 00:21:48,560
Speaker 1: took the message to get here from the satellite, and

436
00:21:48,760 --> 00:21:51,080
Speaker 1: it uses that to figure out where the phone is

437
00:21:51,240 --> 00:21:53,520
Speaker 1: right and it also uses like a map, like your

438
00:21:53,560 --> 00:21:56,000
Speaker 1: phone knows where all the satellites should be at any time,

439
00:21:56,200 --> 00:21:57,960
Speaker 1: so once it gets a signal, it sort of knows

440
00:21:58,000 --> 00:22:01,200
Speaker 1: where it is, yeah, precisely in knows where the satellites are.

441
00:22:01,560 --> 00:22:03,359
Speaker 1: And then it gets these messages. And the messages have

442
00:22:03,359 --> 00:22:05,440
Speaker 1: a little time stamp on them. They say I sent

443
00:22:05,600 --> 00:22:08,320
Speaker 1: this message at exactly this time, and if you get

444
00:22:08,359 --> 00:22:11,840
Speaker 1: this message, you know, seventeen milliseconds later, then you know

445
00:22:11,960 --> 00:22:15,280
Speaker 1: how far the message flew because you knew it flew

446
00:22:15,359 --> 00:22:17,240
Speaker 1: at the speed of light. And you get enough of

447
00:22:17,280 --> 00:22:19,320
Speaker 1: these things and you can figure out where you are.

448
00:22:19,720 --> 00:22:23,040
Speaker 1: And there's an analogous system. There's GPS for deep space.

449
00:22:23,080 --> 00:22:26,800
Speaker 1: There is there's a space GPS. Yeah, there's a space GPS,

450
00:22:26,880 --> 00:22:30,120
Speaker 1: and it's called the Deep Space Network and NASA runs

451
00:22:30,160 --> 00:22:33,359
Speaker 1: it and it basically sends messages out in deep space

452
00:22:33,400 --> 00:22:37,000
Speaker 1: from three locations on the Earth, and satellites get those messages,

453
00:22:37,400 --> 00:22:39,560
Speaker 1: send them back and then we can use that to

454
00:22:39,600 --> 00:22:42,840
Speaker 1: figure out where the satellite is. It's like a reverse

455
00:22:43,160 --> 00:22:45,520
Speaker 1: Why are you seriously, it's like a reverse GPS. It's

456
00:22:45,520 --> 00:22:48,680
Speaker 1: like a reverse GPS. Yeah. What happens is you send

457
00:22:48,680 --> 00:22:51,359
Speaker 1: a message to a satellite and then it comes back

458
00:22:51,400 --> 00:22:53,679
Speaker 1: and you count, well, how long did it take for

459
00:22:53,720 --> 00:22:56,639
Speaker 1: the message to go there and come back, And that

460
00:22:56,720 --> 00:22:59,159
Speaker 1: gives you a sense for the distance. And then when

461
00:22:59,200 --> 00:23:02,119
Speaker 1: the message comes it's a little bit Doppler shifted based

462
00:23:02,119 --> 00:23:04,840
Speaker 1: on the speed of the satellite, and that tells you

463
00:23:05,000 --> 00:23:08,040
Speaker 1: how fast this satellite is moving away from you. So

464
00:23:08,080 --> 00:23:10,359
Speaker 1: it gives you a measure of the current position and

465
00:23:10,600 --> 00:23:13,800
Speaker 1: the velocity of the satellite. But I guess that only

466
00:23:13,840 --> 00:23:16,480
Speaker 1: works for satellites, right, like it doesn't work if from

467
00:23:16,520 --> 00:23:19,000
Speaker 1: in Jupiter or does it. Well, it works for anybody

468
00:23:19,040 --> 00:23:22,200
Speaker 1: that can receive these deep space messages and send them back.

469
00:23:22,960 --> 00:23:25,680
Speaker 1: So it doesn't give you your position relative to Jupiter. Note,

470
00:23:25,760 --> 00:23:29,359
Speaker 1: only gives you your position and velocity relative to Earth. Right,

471
00:23:29,560 --> 00:23:32,000
Speaker 1: But like if you know where Earth is, what this

472
00:23:32,080 --> 00:23:35,040
Speaker 1: signal help you know where you are in this solar system? No,

473
00:23:35,160 --> 00:23:37,640
Speaker 1: because you can't actually do the calculation yourself. And that's

474
00:23:37,640 --> 00:23:40,160
Speaker 1: one problem with this deep space network is that only

475
00:23:40,240 --> 00:23:43,080
Speaker 1: Earth gets to figure it out. Earth gets your message,

476
00:23:43,320 --> 00:23:46,000
Speaker 1: and then the second link gives Earth the information about

477
00:23:46,040 --> 00:23:48,280
Speaker 1: where you are, and then the folks on Earth have

478
00:23:48,320 --> 00:23:50,800
Speaker 1: to calculate Okay, turns out you were in this position

479
00:23:50,880 --> 00:23:53,000
Speaker 1: and send it to you. So it's kind of a

480
00:23:53,080 --> 00:23:55,000
Speaker 1: lot of back and forth. It's not that you can

481
00:23:55,000 --> 00:23:57,560
Speaker 1: just get this message from the deep space network and

482
00:23:57,560 --> 00:23:59,600
Speaker 1: figured it out yourself. The way your phone can from

483
00:24:00,160 --> 00:24:02,760
Speaker 1: s GPS is one directional, right, because it comes with

484
00:24:02,800 --> 00:24:05,960
Speaker 1: these time stamps. Right, So why why couldn't this work

485
00:24:06,000 --> 00:24:08,119
Speaker 1: the same way? The reason is the clock. The clock

486
00:24:08,160 --> 00:24:11,520
Speaker 1: on the satellite is not very good because really accurate

487
00:24:11,520 --> 00:24:14,160
Speaker 1: clocks are necessary to do these calculations. Is because it's

488
00:24:14,280 --> 00:24:17,040
Speaker 1: much more important to be super accurate more important than

489
00:24:17,080 --> 00:24:19,679
Speaker 1: your phone's GPS, and the clocks that are on the

490
00:24:19,680 --> 00:24:21,959
Speaker 1: satellites are not good enough to do this, so they

491
00:24:22,000 --> 00:24:24,360
Speaker 1: have to do the calculation back on Earth and then

492
00:24:24,480 --> 00:24:26,480
Speaker 1: send it to the satellite because on Earth to have

493
00:24:26,560 --> 00:24:30,760
Speaker 1: these super precise atomic clocks that keep everything in lockstep.

494
00:24:31,880 --> 00:24:36,600
Speaker 1: Interesting alright, So we we can't rely on the Earth

495
00:24:36,640 --> 00:24:38,520
Speaker 1: to tell us where we are, like if I'm out

496
00:24:38,520 --> 00:24:41,359
Speaker 1: in space, or can we can we rely on Earth

497
00:24:41,359 --> 00:24:43,440
Speaker 1: to tell me where I am. Earth can figure out

498
00:24:43,480 --> 00:24:45,800
Speaker 1: where you are, how far you are from the Earth,

499
00:24:45,840 --> 00:24:48,440
Speaker 1: and how fast you're going, but you know, it's kind

500
00:24:48,480 --> 00:24:51,679
Speaker 1: of limited. Like they can get really precise measurements of

501
00:24:51,720 --> 00:24:54,600
Speaker 1: where you are up to about one meter, which is

502
00:24:54,640 --> 00:24:57,920
Speaker 1: really pretty amazing, like you're out you know Jupiter distance,

503
00:24:57,960 --> 00:25:00,119
Speaker 1: and Earth can measure how far away you are to

504
00:25:00,280 --> 00:25:03,600
Speaker 1: within one meter based on the balance of the echo,

505
00:25:03,760 --> 00:25:06,560
Speaker 1: like the signal coming back and going there and back. Yeah,

506
00:25:06,640 --> 00:25:10,320
Speaker 1: just timing the echo because they have really precise atomic clocks.

507
00:25:10,359 --> 00:25:12,280
Speaker 1: But what they can't do is figure out like where

508
00:25:12,280 --> 00:25:16,119
Speaker 1: you are laterally, like your angle because there they don't

509
00:25:16,119 --> 00:25:19,439
Speaker 1: have an echo measurement, right, and so they're the uncertainties

510
00:25:19,480 --> 00:25:23,439
Speaker 1: more like four kilometers for every a U the distance

511
00:25:23,480 --> 00:25:27,760
Speaker 1: between the Earth and the Sun. I see, because you know,

512
00:25:28,040 --> 00:25:30,240
Speaker 1: if we're out by Jupiter, we don't shine like a star,

513
00:25:30,800 --> 00:25:33,240
Speaker 1: that's right, right, Like we're not visible to the Earth,

514
00:25:33,560 --> 00:25:35,159
Speaker 1: So they have no idea where we are. They just

515
00:25:35,200 --> 00:25:36,600
Speaker 1: know kind of how far we are. They know how

516
00:25:36,600 --> 00:25:38,200
Speaker 1: far you are, and they figure out where you are

517
00:25:38,280 --> 00:25:41,840
Speaker 1: laterally basically using dead reckoning and then correcting using these

518
00:25:41,920 --> 00:25:45,360
Speaker 1: radio measurements. But you know, that's a pretty big uncertainty.

519
00:25:45,359 --> 00:25:47,400
Speaker 1: If you get out to like the distance of Pluto,

520
00:25:47,800 --> 00:25:51,960
Speaker 1: then they're uncertainties two hundred kilometers, which is really big

521
00:25:52,040 --> 00:25:55,840
Speaker 1: if you're trying to enter into the orbit of Pluto. Yeah. Yeah,

522
00:25:55,880 --> 00:25:59,399
Speaker 1: that sounds like a pretty big error. Viewer off by

523
00:25:59,400 --> 00:26:04,040
Speaker 1: two meters in your phone GPS, you be in a

524
00:26:04,080 --> 00:26:06,920
Speaker 1: whole different state. Yeah. And so practically, what these folks

525
00:26:06,960 --> 00:26:09,679
Speaker 1: do is they use landmarks in the Solar system too

526
00:26:09,720 --> 00:26:12,320
Speaker 1: correct So if you're getting near Jupiter, it sund I

527
00:26:12,359 --> 00:26:14,639
Speaker 1: can be like, okay, I see where Jupiter is. It

528
00:26:14,680 --> 00:26:17,239
Speaker 1: can compare it to where thought Jupiter should be, and

529
00:26:17,240 --> 00:26:19,160
Speaker 1: you can use that to correct. So you're like you're

530
00:26:19,160 --> 00:26:21,880
Speaker 1: getting landmarks. You're like, oh, you're driving your friend's house

531
00:26:22,080 --> 00:26:24,320
Speaker 1: is supposed to be a hill there. Hoops, I must

532
00:26:24,320 --> 00:26:27,040
Speaker 1: be in the wrong spot passing to McDonald. I know

533
00:26:27,160 --> 00:26:30,240
Speaker 1: I'm halfway there kind of thing. Yeah, And so cameras

534
00:26:30,280 --> 00:26:33,720
Speaker 1: on board can give accurate measurements of nearby objects, not

535
00:26:33,840 --> 00:26:36,680
Speaker 1: very far away, only very nearby. You see a big,

536
00:26:36,720 --> 00:26:39,640
Speaker 1: well known asteroid, you pass the Moon or a planet,

537
00:26:39,800 --> 00:26:41,960
Speaker 1: then you can correct You're no longer reliant on the

538
00:26:42,000 --> 00:26:45,359
Speaker 1: messages from earthly interesting, but the satellite does that calculation

539
00:26:45,480 --> 00:26:47,399
Speaker 1: or like it has to send the picture bag and

540
00:26:47,400 --> 00:26:49,720
Speaker 1: then here on Earth were like, oh, it just pass Jupiter.

541
00:26:49,880 --> 00:26:51,720
Speaker 1: This is where you are. Yeah, that's all done on

542
00:26:51,800 --> 00:26:54,160
Speaker 1: Earth currently sends the data back and then we can

543
00:26:54,160 --> 00:26:56,840
Speaker 1: get corrections. And that's one of the problems is that

544
00:26:56,960 --> 00:26:59,359
Speaker 1: a lot of this stuff relies on calculations done on

545
00:26:59,400 --> 00:27:02,439
Speaker 1: Earth and then these back and forth communications with the

546
00:27:02,480 --> 00:27:05,399
Speaker 1: deep space network, which tie up the deep space network.

547
00:27:05,400 --> 00:27:07,439
Speaker 1: You know, you're only talking to one satellite. All the

548
00:27:07,480 --> 00:27:10,159
Speaker 1: other ones are waiting, so you can only talk to like,

549
00:27:10,320 --> 00:27:12,280
Speaker 1: you know, a few of them at a time. And

550
00:27:12,640 --> 00:27:14,959
Speaker 1: that's pretty serious because like GPS doesn't work that way.

551
00:27:15,040 --> 00:27:18,040
Speaker 1: GPS just sends out its messages and all the phones

552
00:27:18,080 --> 00:27:20,159
Speaker 1: in the world just kind of listen. It doesn't have

553
00:27:20,200 --> 00:27:22,119
Speaker 1: to be bothered by the fact that I'm using it

554
00:27:22,119 --> 00:27:24,000
Speaker 1: and somebody else is using it at the same time.

555
00:27:24,440 --> 00:27:26,840
Speaker 1: But deep space network gets tied up every time a

556
00:27:26,920 --> 00:27:30,040
Speaker 1: satellite needs to figure out its position. So they have

557
00:27:30,320 --> 00:27:32,639
Speaker 1: a new idea for how to improve this so that

558
00:27:32,640 --> 00:27:35,680
Speaker 1: it can be more like GPS. Well, how does that work?

559
00:27:35,800 --> 00:27:38,280
Speaker 1: Just put more clocks in it, or yes, build a

560
00:27:38,359 --> 00:27:41,480
Speaker 1: really precise clock and put it on the satellite. The

561
00:27:41,560 --> 00:27:44,679
Speaker 1: most precise clocks we have are atomic clocks. These are

562
00:27:44,720 --> 00:27:48,760
Speaker 1: clocks that measure little atoms doing very precise wiggles that

563
00:27:48,920 --> 00:27:52,040
Speaker 1: like vibrated very specific frequency. One of the most precise

564
00:27:52,080 --> 00:27:54,760
Speaker 1: things in the universe because it just happens over and

565
00:27:54,880 --> 00:27:58,760
Speaker 1: over and over again exactly the same time step. But

566
00:27:58,840 --> 00:28:02,560
Speaker 1: these atomic clocks are expensive and they're big, and so

567
00:28:02,600 --> 00:28:05,560
Speaker 1: the reason that we don't have good clocks on satellites

568
00:28:05,640 --> 00:28:09,639
Speaker 1: is because nobody's ever miniaturized them. So NASA spent a

569
00:28:09,640 --> 00:28:12,760
Speaker 1: lot of time building a deep space atomic clock, basically

570
00:28:12,880 --> 00:28:16,000
Speaker 1: a miniaturized version of atomic clock you can put on

571
00:28:16,080 --> 00:28:18,880
Speaker 1: the satellite. And is it a lot smaller or yeah,

572
00:28:18,960 --> 00:28:21,439
Speaker 1: it's a lot smaller, and it's a lot cheaper, and

573
00:28:21,480 --> 00:28:23,760
Speaker 1: it's about the size of a toaster. Wow. So you

574
00:28:23,840 --> 00:28:27,480
Speaker 1: wouldn't want to wear this atomic clock. It's not it's

575
00:28:27,480 --> 00:28:31,040
Speaker 1: not ready for wristwatch use. If you want to be

576
00:28:31,119 --> 00:28:34,680
Speaker 1: super untime to meetings and podcast recordings, I could wear

577
00:28:34,720 --> 00:28:37,320
Speaker 1: an atomic clock, but it might be a little inconvenient. No,

578
00:28:37,400 --> 00:28:39,520
Speaker 1: And these atomic clocks cost you know, enough fifty to

579
00:28:39,600 --> 00:28:42,840
Speaker 1: a hundred thousand dollars, which amazingly is actually cheaper than

580
00:28:42,920 --> 00:28:46,440
Speaker 1: some wristwatches you can buy for wearing. I never understood that.

581
00:28:46,600 --> 00:28:50,360
Speaker 1: But some people spend a ridiculous amount the gold plated iPhones, right, Yeah, Well,

582
00:28:50,400 --> 00:28:52,600
Speaker 1: I spent a few years in Switzerland where they have

583
00:28:52,640 --> 00:28:55,320
Speaker 1: these ridiculous watch shops. You can go in and spend

584
00:28:55,320 --> 00:28:58,600
Speaker 1: two hundred thousand dollars on a fancy watch. But it's

585
00:28:58,640 --> 00:29:01,920
Speaker 1: like hand built with all these little levers and gears thereby,

586
00:29:02,240 --> 00:29:04,600
Speaker 1: you know, dwarves underground or something I don't know, And

587
00:29:04,720 --> 00:29:08,440
Speaker 1: it's not even as accurate as a toaster exactly exactly.

588
00:29:08,440 --> 00:29:10,760
Speaker 1: I'll take a toaster's eye atomic watch from my wrist

589
00:29:11,040 --> 00:29:14,640
Speaker 1: any day. But the idea there is if you have

590
00:29:14,800 --> 00:29:18,120
Speaker 1: this atomic clock on the satellite, then it can get

591
00:29:18,240 --> 00:29:20,880
Speaker 1: messages from the Deep Space Network that have time stamps

592
00:29:20,920 --> 00:29:23,920
Speaker 1: on them to say we sent this message at whatever time,

593
00:29:24,280 --> 00:29:27,120
Speaker 1: and you can just compare that too. It's atomic clock

594
00:29:27,440 --> 00:29:29,600
Speaker 1: and they say, oh, it took x seconds to get here.

595
00:29:29,880 --> 00:29:32,440
Speaker 1: I can figure out where I am myself. And that's

596
00:29:32,440 --> 00:29:36,120
Speaker 1: a big step forward in what they call autonomous satellite navigation,

597
00:29:36,160 --> 00:29:38,959
Speaker 1: with the satellites are just sort of driving themselves, right then,

598
00:29:39,000 --> 00:29:41,840
Speaker 1: it's more like the GPS we have on our phones. Yeah, exactly,

599
00:29:42,080 --> 00:29:44,240
Speaker 1: and you can just be sort of passive. The folks

600
00:29:44,400 --> 00:29:47,360
Speaker 1: at home don't have to do these calculations themselves and

601
00:29:47,480 --> 00:29:50,240
Speaker 1: updated to the satellite. So there are fewer links because

602
00:29:50,240 --> 00:29:52,840
Speaker 1: the Deep space network is kind of sort of overburdened

603
00:29:52,920 --> 00:29:54,920
Speaker 1: right now. It's got like too many things to do,

604
00:29:55,040 --> 00:29:58,000
Speaker 1: is I mean time slice between too many projects. So

605
00:29:58,080 --> 00:30:00,400
Speaker 1: this would really free it up, all right. Well, it

606
00:30:00,400 --> 00:30:02,840
Speaker 1: sounds like things are looking good for navigating within the

607
00:30:02,920 --> 00:30:06,160
Speaker 1: Solar System. So we're getting better clocks on these satellites

608
00:30:06,160 --> 00:30:10,360
Speaker 1: and spacecraft, and we're also we can also use familiar

609
00:30:10,600 --> 00:30:13,640
Speaker 1: landmarks like Jupiter or other planets or the Sun to

610
00:30:13,720 --> 00:30:16,720
Speaker 1: sort of orient where we are within the Solar System.

611
00:30:16,760 --> 00:30:18,520
Speaker 1: That's right, but then it sort of gets trickier one

612
00:30:18,680 --> 00:30:21,160
Speaker 1: once we get out into space. Right, Yeah, all these

613
00:30:21,200 --> 00:30:24,240
Speaker 1: things still rely on being able to contact Earth. You're

614
00:30:24,240 --> 00:30:27,280
Speaker 1: getting these messages from the Deep Space Network, which is

615
00:30:27,360 --> 00:30:29,680
Speaker 1: on Earth, and if you want to navigate to like

616
00:30:29,720 --> 00:30:33,440
Speaker 1: Alpha Centauri or halfway across the galaxy, you don't want

617
00:30:33,480 --> 00:30:35,240
Speaker 1: to be getting messages from Earth. They're gonna be way

618
00:30:35,240 --> 00:30:37,240
Speaker 1: too faint. You're not gonna be able to pick remain.

619
00:30:37,520 --> 00:30:40,320
Speaker 1: So you need a broader system. You need a galaxy

620
00:30:40,480 --> 00:30:43,040
Speaker 1: spanning system. In order to get you out of the

621
00:30:43,080 --> 00:30:45,520
Speaker 1: Solar System and still make it to McDonald's. We need

622
00:30:45,560 --> 00:30:51,680
Speaker 1: like a like a capital GPS galactic positioning system. All right, Well,

623
00:30:51,720 --> 00:30:53,920
Speaker 1: let's get into how you would actually navigate if you

624
00:30:53,960 --> 00:30:56,160
Speaker 1: wanted to venture out from the Solar System or even

625
00:30:56,200 --> 00:30:59,040
Speaker 1: go to another galaxy. But first let's take a quick break.

626
00:31:10,800 --> 00:31:13,160
Speaker 1: All right. There we're talking about how did not get

627
00:31:13,200 --> 00:31:18,440
Speaker 1: lost in space? Although that's such a fun show, is it?

628
00:31:18,520 --> 00:31:19,920
Speaker 1: You like that show that, the new one or the

629
00:31:19,960 --> 00:31:21,320
Speaker 1: old one. I like the old one, but the new

630
00:31:21,360 --> 00:31:23,080
Speaker 1: one's fun watching with the whole family because you know,

631
00:31:23,120 --> 00:31:26,080
Speaker 1: it's a bit of a family adventure, some family tension there,

632
00:31:26,080 --> 00:31:29,080
Speaker 1: you know, you leave somebody behind. If you were frozen

633
00:31:29,200 --> 00:31:32,080
Speaker 1: underwater on some alien moon, would your family stop and

634
00:31:32,080 --> 00:31:34,600
Speaker 1: save you or not? Oh? Man, To me, it was

635
00:31:34,680 --> 00:31:36,840
Speaker 1: almost too much family drama. I'm like, where is the

636
00:31:36,880 --> 00:31:42,320
Speaker 1: space and they're getting lost in space they're like melting ice. Yeah, exactly.

637
00:31:42,520 --> 00:31:45,680
Speaker 1: I thought it was good anyway, A lot of fun anyway. So, yeah,

638
00:31:45,760 --> 00:31:48,440
Speaker 1: it's a problem if you go out into space, especially

639
00:31:48,480 --> 00:31:50,400
Speaker 1: you can like in another part of the galaxy where

640
00:31:50,400 --> 00:31:52,480
Speaker 1: the stars are in a totally different arrangement. How do

641
00:31:52,520 --> 00:31:53,800
Speaker 1: you get around, how do you know where you are,

642
00:31:53,840 --> 00:31:56,240
Speaker 1: and how do you know where to go? So what

643
00:31:56,320 --> 00:31:58,080
Speaker 1: can we do then, Daniel? Yeah, well, what you need

644
00:31:58,120 --> 00:32:00,880
Speaker 1: is some other source of signals. Either have a very

645
00:32:00,960 --> 00:32:03,560
Speaker 1: accurate galactive map of where all the stars are, but

646
00:32:03,600 --> 00:32:06,040
Speaker 1: as you say, these things are changing in time and

647
00:32:06,160 --> 00:32:09,160
Speaker 1: we have only measurements from Earth and those positions are

648
00:32:09,200 --> 00:32:11,680
Speaker 1: not that accurate. Which you really need is some sort

649
00:32:11,720 --> 00:32:16,040
Speaker 1: of network of signals from all over the galaxy sending

650
00:32:16,080 --> 00:32:18,400
Speaker 1: you time stamped messages. I mean, if you could design

651
00:32:18,440 --> 00:32:21,720
Speaker 1: it yourself, you would have a bunch of sources around

652
00:32:21,760 --> 00:32:25,680
Speaker 1: the galaxy sending you messages saying time equals one time

653
00:32:25,680 --> 00:32:28,760
Speaker 1: equals two time equals three, right, and from those like

654
00:32:28,800 --> 00:32:31,880
Speaker 1: the like the GPS satellites we have just now on Earth,

655
00:32:32,080 --> 00:32:34,160
Speaker 1: you just have If you could just have GPS satellites

656
00:32:34,200 --> 00:32:37,400
Speaker 1: all the way through the galaxy super powerful, that would

657
00:32:37,440 --> 00:32:39,800
Speaker 1: be enough because you could use the nearest satellites to

658
00:32:39,840 --> 00:32:42,240
Speaker 1: figure out how far you are from each one, and

659
00:32:42,320 --> 00:32:44,560
Speaker 1: you need three of them to triangulate your position in

660
00:32:44,640 --> 00:32:47,800
Speaker 1: three D space and then you be golden. But you

661
00:32:47,840 --> 00:32:50,040
Speaker 1: know that's a trillion dollar program, right, could could you

662
00:32:50,160 --> 00:32:52,920
Speaker 1: use like galaxies to orienter cell? Like you know, like

663
00:32:52,960 --> 00:32:55,000
Speaker 1: if I'm in somewhere in the Milky Way, I could

664
00:32:55,080 --> 00:32:57,400
Speaker 1: tell where the center of the Milky Way was maybe,

665
00:32:57,880 --> 00:33:01,080
Speaker 1: and I could look for other galaxy ease out there,

666
00:33:01,480 --> 00:33:03,760
Speaker 1: and so can I use that to orient myself? Yeah,

667
00:33:03,800 --> 00:33:05,880
Speaker 1: And you can get a rough orientation that way, right,

668
00:33:05,920 --> 00:33:08,600
Speaker 1: you can tell you know where Andrameda is relative to

669
00:33:08,600 --> 00:33:11,560
Speaker 1: the Milky Way, So you can spin yourself around and

670
00:33:11,560 --> 00:33:14,080
Speaker 1: tell where and Drameda is. But it's very rough, I mean,

671
00:33:14,080 --> 00:33:16,959
Speaker 1: and Drameda is really far away, and so measuring its

672
00:33:17,040 --> 00:33:20,720
Speaker 1: location precisely is not that helpful. We need much more

673
00:33:20,760 --> 00:33:23,360
Speaker 1: precision than you can get from just like fixing the

674
00:33:23,440 --> 00:33:26,240
Speaker 1: positions of other galaxies, like, yeah, that will tell you roughly.

675
00:33:26,600 --> 00:33:28,520
Speaker 1: But if you want to navigate and you want to

676
00:33:28,520 --> 00:33:30,520
Speaker 1: save fuel and you want to make it with your

677
00:33:30,720 --> 00:33:34,760
Speaker 1: thousand frozen human bodies to Alpha Centauri or whatever, then

678
00:33:35,080 --> 00:33:36,560
Speaker 1: you've got to be more precise than that. You don't

679
00:33:36,560 --> 00:33:39,440
Speaker 1: want to miss by a few million kilometers, You got it,

680
00:33:39,840 --> 00:33:41,959
Speaker 1: You do not, And then they start to warm up

681
00:33:41,960 --> 00:33:44,920
Speaker 1: and there, you know, expecting the land in Alpha Centauri

682
00:33:45,000 --> 00:33:48,040
Speaker 1: and have breakfast, and you didn't bring any months and

683
00:33:48,040 --> 00:33:50,400
Speaker 1: so and so you're saying that one idea could could be,

684
00:33:50,440 --> 00:33:53,520
Speaker 1: like to make these GPS satellites and put them all

685
00:33:53,520 --> 00:33:56,440
Speaker 1: over the galaxy. But that's really expensive. Yeah, that's ridiculous,

686
00:33:56,440 --> 00:33:58,560
Speaker 1: Like we didn't even know how to get them there, right,

687
00:33:58,560 --> 00:34:03,680
Speaker 1: that's the whole problem. You're right, How would the satellites

688
00:34:03,720 --> 00:34:06,520
Speaker 1: know where to go or where they are? How would

689
00:34:06,560 --> 00:34:09,280
Speaker 1: we know where they are? We'd have to bootstrap them somehow.

690
00:34:09,719 --> 00:34:11,520
Speaker 1: If you don't know where the satellites are, then they're

691
00:34:11,520 --> 00:34:13,960
Speaker 1: not very useful right there, Like here's a signal from

692
00:34:14,000 --> 00:34:17,319
Speaker 1: someplace we don't know, thank you very much. That's useless.

693
00:34:17,400 --> 00:34:20,720
Speaker 1: So what you need to do is find some naturally

694
00:34:20,800 --> 00:34:24,920
Speaker 1: occurring equivalent something in the galaxy that operates similar to

695
00:34:25,040 --> 00:34:27,600
Speaker 1: GPS that lets you figure out where you are. And

696
00:34:27,640 --> 00:34:32,880
Speaker 1: it turns out the galaxy provides is it alien satellites? Daniel,

697
00:34:32,880 --> 00:34:35,479
Speaker 1: are you going for the alien button? I didn't even

698
00:34:35,560 --> 00:34:38,200
Speaker 1: think about the alien button, but now I am. Now

699
00:34:38,200 --> 00:34:41,600
Speaker 1: I'm wondering if aliens are using our GPS system to

700
00:34:41,680 --> 00:34:45,680
Speaker 1: navigate our solar system right to us. Yes, well, if

701
00:34:45,719 --> 00:34:49,160
Speaker 1: you enter the solar system that already had alien civilization

702
00:34:49,200 --> 00:34:51,600
Speaker 1: and have GPS signals, then yeah, you could use it

703
00:34:51,800 --> 00:34:54,919
Speaker 1: without them even noticing, because it's a passive system, right right,

704
00:34:55,040 --> 00:34:59,920
Speaker 1: then maybe they're using us as a GPS exactly exactly,

705
00:35:00,360 --> 00:35:04,360
Speaker 1: that's the concerned. But even without aliens, there are naturally occurring,

706
00:35:04,840 --> 00:35:07,799
Speaker 1: very regular clocks in our galaxy interesting and they are

707
00:35:07,800 --> 00:35:10,919
Speaker 1: called pulsars. You don't have to build them, they're already there.

708
00:35:11,000 --> 00:35:13,719
Speaker 1: They are already there. We talked on the podcast before

709
00:35:13,760 --> 00:35:17,480
Speaker 1: about what happens when really massive stars collapse that they

710
00:35:17,520 --> 00:35:20,320
Speaker 1: blow up, there's a supernova, and then if there's enough

711
00:35:20,400 --> 00:35:22,719
Speaker 1: stuff in the center of it, in the core, but

712
00:35:22,760 --> 00:35:24,640
Speaker 1: not enough to make a black hole, they can form

713
00:35:24,680 --> 00:35:28,400
Speaker 1: this thing called a neutron star, which is a ridiculously

714
00:35:28,520 --> 00:35:31,759
Speaker 1: dense ball of matter. It's called like the mass of

715
00:35:31,760 --> 00:35:34,920
Speaker 1: the Sun, but it's the size of a city. Right,

716
00:35:34,960 --> 00:35:37,400
Speaker 1: It's it's like almost a black hole. It's almost a

717
00:35:37,440 --> 00:35:40,439
Speaker 1: black hole. Yeah, if your star was like eighty two

718
00:35:40,480 --> 00:35:42,960
Speaker 1: thirty masses of the Sun, then you're probably going to

719
00:35:43,040 --> 00:35:45,120
Speaker 1: turn into a neutron star. If it was heavier than

720
00:35:45,160 --> 00:35:47,640
Speaker 1: you probably get into a black hole. But some of

721
00:35:47,680 --> 00:35:51,239
Speaker 1: these neutron stars are amazing because they have a magnetic

722
00:35:51,320 --> 00:35:55,719
Speaker 1: field which is really intense, and the magnetic field means

723
00:35:55,760 --> 00:35:59,040
Speaker 1: that there's a huge column of radiation that's spewed out

724
00:35:59,120 --> 00:36:01,840
Speaker 1: from the north magnetic field and the south magnetic field.

725
00:36:01,840 --> 00:36:05,040
Speaker 1: So they're like shining a really bright light of radiation

726
00:36:05,400 --> 00:36:08,880
Speaker 1: in two directions in space. Right, Because the stars themselves

727
00:36:08,880 --> 00:36:11,719
Speaker 1: don't shine that much, but like the chaos they cause

728
00:36:11,800 --> 00:36:14,640
Speaker 1: around them with the magnetic field and all the stuff

729
00:36:14,680 --> 00:36:17,440
Speaker 1: around them, then that is what glows and points in

730
00:36:17,480 --> 00:36:20,759
Speaker 1: a particular direction. Exactly. There's no fusion happening inside a

731
00:36:20,800 --> 00:36:23,399
Speaker 1: neutron star, but there's still an intense amount of other

732
00:36:23,480 --> 00:36:26,879
Speaker 1: radiation produced, and the magnetic field funnels it into these

733
00:36:26,920 --> 00:36:30,560
Speaker 1: type beams. And then if the magnetic north pole is

734
00:36:30,600 --> 00:36:33,920
Speaker 1: not aligned with the spinning of the star, right, it's

735
00:36:33,960 --> 00:36:36,480
Speaker 1: not perfectly aligned like on Earth. Then what you get

736
00:36:36,560 --> 00:36:40,400
Speaker 1: is this neutron star that's sweeping around. It's rotating, but

737
00:36:40,480 --> 00:36:44,680
Speaker 1: the direction in which its signal is beaming keeps scanning

738
00:36:44,680 --> 00:36:48,880
Speaker 1: through the galg like a galactic lighthouse, you know, like

739
00:36:48,920 --> 00:36:52,120
Speaker 1: a spotlight that just miss just like that, yeah, Or

740
00:36:52,160 --> 00:36:54,239
Speaker 1: like just like on the top of a police car,

741
00:36:54,360 --> 00:36:57,680
Speaker 1: you have this rotating red light and it never turns

742
00:36:57,680 --> 00:36:59,840
Speaker 1: on or off, but it looks to you like it's flashing.

743
00:37:00,200 --> 00:37:02,400
Speaker 1: So from Earth, if you look at a pulsar, it

744
00:37:02,480 --> 00:37:06,640
Speaker 1: goes on off, on off, on off, on off very regularly,

745
00:37:07,000 --> 00:37:09,880
Speaker 1: just like a lighthouse would or a police light, and

746
00:37:09,920 --> 00:37:11,759
Speaker 1: it's not actually turning on off, it's just sort of

747
00:37:11,800 --> 00:37:14,759
Speaker 1: sweeping past you. Right. So if we can use these

748
00:37:14,800 --> 00:37:17,040
Speaker 1: to kind of tell where we are, like as as

749
00:37:17,120 --> 00:37:20,960
Speaker 1: literally like lighthouses in space, sort of like lighthouses in space,

750
00:37:21,160 --> 00:37:24,520
Speaker 1: And the reason is that they're incredibly accurate. They have

751
00:37:24,880 --> 00:37:28,160
Speaker 1: about as much regularity as an atomic clock. Really, like

752
00:37:28,239 --> 00:37:32,040
Speaker 1: these little particles in very special conditions and cold climates

753
00:37:32,040 --> 00:37:36,280
Speaker 1: and special laboratories are very regular. But these enormous, massive

754
00:37:36,360 --> 00:37:40,560
Speaker 1: spinning hunks of neutrons are also regular, and so they're

755
00:37:40,560 --> 00:37:45,280
Speaker 1: basically like a very powerful galactic clock that's constantly descending

756
00:37:45,280 --> 00:37:50,439
Speaker 1: out a pulse like tick tick tick. Suddenly that makes

757
00:37:50,440 --> 00:37:53,120
Speaker 1: a nice guy a little more stressful. It's full of

758
00:37:53,200 --> 00:37:57,040
Speaker 1: ticking clocks. But it's it's like crazy periods to right,

759
00:37:57,080 --> 00:37:59,080
Speaker 1: it's not like tick tack tick. Take. It's like every

760
00:37:59,120 --> 00:38:02,480
Speaker 1: twenty millis like and they're shining. There's a big variety

761
00:38:02,480 --> 00:38:05,640
Speaker 1: of them, from radio pulsars down to X ray pulsars.

762
00:38:05,640 --> 00:38:08,759
Speaker 1: It depends, as you say, on their period. And these

763
00:38:08,760 --> 00:38:11,640
Speaker 1: ones that are very fast and like twenty milliseconds, these

764
00:38:11,640 --> 00:38:14,200
Speaker 1: are the best ones to use for timing. And it's

765
00:38:14,200 --> 00:38:18,560
Speaker 1: hard to imagine, like an enormous, super dense star boiled

766
00:38:18,640 --> 00:38:22,640
Speaker 1: down into a tiny object that spins every twenty milliseconds. Right,

767
00:38:22,680 --> 00:38:25,480
Speaker 1: It's like, hey, thousands and thousands of times a second,

768
00:38:25,880 --> 00:38:28,720
Speaker 1: this huge thing is spinning. It's it's an incredible amount

769
00:38:28,719 --> 00:38:31,000
Speaker 1: of energy. It's mind blowing. So we can use these

770
00:38:31,239 --> 00:38:34,239
Speaker 1: because we know from Earth where they are, and so

771
00:38:34,280 --> 00:38:37,280
Speaker 1: if you're out there in space, you could maybe find

772
00:38:37,320 --> 00:38:40,960
Speaker 1: them by looking out, and then you can tell kind

773
00:38:40,960 --> 00:38:42,759
Speaker 1: of where you are because you could recognize them. Buy

774
00:38:42,840 --> 00:38:45,959
Speaker 1: what their period. Each one has its own fingerprint because

775
00:38:45,960 --> 00:38:48,120
Speaker 1: of its period, and you already know where they are,

776
00:38:48,200 --> 00:38:50,880
Speaker 1: so you find them, you identified and you're like, okay,

777
00:38:50,880 --> 00:38:53,600
Speaker 1: this is pulsar x J seventeen or whatever. And then

778
00:38:53,600 --> 00:38:57,040
Speaker 1: you listen to the pulses, you know, tick tick tick,

779
00:38:57,600 --> 00:39:00,680
Speaker 1: and based on the pulses that you hear, you can

780
00:39:00,680 --> 00:39:03,520
Speaker 1: tell where in the wave form you are. Now, the

781
00:39:03,560 --> 00:39:06,480
Speaker 1: problem is they don't send messages like the GPS satellites.

782
00:39:06,520 --> 00:39:09,600
Speaker 1: The GPS satellite say okay, it's time equals seven, it's

783
00:39:09,640 --> 00:39:11,879
Speaker 1: time equals eight, and then when it gets to you,

784
00:39:11,880 --> 00:39:13,840
Speaker 1: you can compare against your own clock they have. You

785
00:39:13,880 --> 00:39:16,640
Speaker 1: have like synchronized clocks on each side, so you can

786
00:39:16,680 --> 00:39:19,120
Speaker 1: measure how long it takes the signal to get there.

787
00:39:19,440 --> 00:39:22,600
Speaker 1: That's from the GPS. Pulsars aren't as convenient. They don't

788
00:39:22,600 --> 00:39:26,080
Speaker 1: have a clock built in that labels each pulse separately,

789
00:39:26,320 --> 00:39:28,799
Speaker 1: so it's harder to tell exactly how long it took

790
00:39:29,000 --> 00:39:30,680
Speaker 1: the pulse to get there. Right, But why do you

791
00:39:30,680 --> 00:39:32,799
Speaker 1: need to know that? Couldn't you just kind of look

792
00:39:32,880 --> 00:39:35,200
Speaker 1: where they are and you know the angle to you,

793
00:39:35,480 --> 00:39:37,239
Speaker 1: and then use like three or four of them to

794
00:39:37,320 --> 00:39:39,600
Speaker 1: kind of triangulate where you are. What you really want

795
00:39:39,640 --> 00:39:42,919
Speaker 1: to know is your distance to an individual pulsar, because

796
00:39:42,960 --> 00:39:45,880
Speaker 1: that defines your position on the surface of a sphere

797
00:39:45,920 --> 00:39:48,720
Speaker 1: that surrounds that pulsar. And you do it for another pulsar,

798
00:39:48,920 --> 00:39:51,840
Speaker 1: and then your distance is defined by where those spheres intersect,

799
00:39:52,080 --> 00:39:54,160
Speaker 1: and we do it for three pulsars. Then you can

800
00:39:54,160 --> 00:39:56,960
Speaker 1: figure out where your distance is exactly in three D space.

801
00:39:57,120 --> 00:39:58,839
Speaker 1: You're right there. You can tell roughly where you are

802
00:39:58,920 --> 00:40:01,239
Speaker 1: by the angles, but that's not precise enough. Which you

803
00:40:01,280 --> 00:40:03,880
Speaker 1: really want to know is the distance to these things? Really?

804
00:40:03,920 --> 00:40:06,239
Speaker 1: Why is the angle not precise enough? Because these things

805
00:40:06,239 --> 00:40:09,240
Speaker 1: are really really far away, right, and so a pretty

806
00:40:09,239 --> 00:40:11,640
Speaker 1: big change in the location of the pulse are relative

807
00:40:11,640 --> 00:40:14,640
Speaker 1: to you corresponds to a really small change in the angle.

808
00:40:14,960 --> 00:40:17,120
Speaker 1: So what you really want to know is the radial distance,

809
00:40:17,360 --> 00:40:19,799
Speaker 1: not just the angle. Oh, I see, it works if

810
00:40:19,840 --> 00:40:22,560
Speaker 1: you're moving a huge distances, but like you couldn't tell

811
00:40:22,600 --> 00:40:24,600
Speaker 1: you like by the meter where you are, yeah, or

812
00:40:24,640 --> 00:40:26,480
Speaker 1: if you're really close to something, like if you're really

813
00:40:26,520 --> 00:40:29,680
Speaker 1: close to Jupiter, then it's angle relative to you has

814
00:40:29,719 --> 00:40:32,520
Speaker 1: a lot of powerful information about your location. But if

815
00:40:32,600 --> 00:40:35,960
Speaker 1: Jupiter is really far away, then that information loses value

816
00:40:36,000 --> 00:40:38,879
Speaker 1: and all these pulsars are pretty far away. But there's

817
00:40:38,880 --> 00:40:42,520
Speaker 1: actually a really cool trick to overcoming this problem of

818
00:40:42,880 --> 00:40:47,200
Speaker 1: pulsars not being like GPS statelines just using because great,

819
00:40:47,200 --> 00:40:49,319
Speaker 1: because I don't have the time stamp. They just have

820
00:40:49,360 --> 00:40:51,560
Speaker 1: a pulse. Yeah, so all you know is where you

821
00:40:51,600 --> 00:40:54,799
Speaker 1: are on the pulse. And so say these pulses are like,

822
00:40:55,200 --> 00:40:58,680
Speaker 1: you know, a kilometer long, for example, So if you

823
00:40:58,880 --> 00:41:01,399
Speaker 1: listen to a specific pulse, are that you could tell

824
00:41:01,440 --> 00:41:05,000
Speaker 1: where you are within that one kilometer long pulse. You're like, oh,

825
00:41:05,040 --> 00:41:06,279
Speaker 1: I'm at the top of it, or I'm at the

826
00:41:06,320 --> 00:41:08,080
Speaker 1: bottom of it, or I mean the quiet part of

827
00:41:08,080 --> 00:41:10,360
Speaker 1: it or the loud part of it. That doesn't actually

828
00:41:10,360 --> 00:41:12,600
Speaker 1: tell you how far you are from the pulse are.

829
00:41:12,680 --> 00:41:15,680
Speaker 1: What you know is how far you are through one

830
00:41:15,920 --> 00:41:19,000
Speaker 1: pulse length, but you don't know how many more pulse

831
00:41:19,120 --> 00:41:22,120
Speaker 1: lengths there are between you and the pulse are. If

832
00:41:22,160 --> 00:41:24,919
Speaker 1: you know you're halfway through its pulse, then you could

833
00:41:24,920 --> 00:41:27,760
Speaker 1: be half a pulse length away from the original pulsar,

834
00:41:28,280 --> 00:41:31,080
Speaker 1: or you could be one and a half pulse lengths away,

835
00:41:31,200 --> 00:41:34,800
Speaker 1: or three hundred forty two and a half pulse lengths away.

836
00:41:35,040 --> 00:41:39,400
Speaker 1: There's an infinite number of possibilities. So instead of locating

837
00:41:39,400 --> 00:41:42,040
Speaker 1: you onto a single sphere when you know the distance,

838
00:41:42,320 --> 00:41:46,000
Speaker 1: it's actually given you an infinite number of spheres, each

839
00:41:46,040 --> 00:41:49,080
Speaker 1: one one pulse length away, because all of those are

840
00:41:49,120 --> 00:41:53,000
Speaker 1: consistent with what you're seeing. That's not as good as GPS,

841
00:41:53,040 --> 00:41:55,880
Speaker 1: but you know it can still work because you can

842
00:41:55,920 --> 00:41:58,840
Speaker 1: do the same thing for another pulsar and get another

843
00:41:58,920 --> 00:42:02,000
Speaker 1: set of spheres, and then find a third pulsar and

844
00:42:02,040 --> 00:42:05,000
Speaker 1: get a third set of spheres, And where those spheares

845
00:42:05,080 --> 00:42:07,880
Speaker 1: intersect is the number of places that you could be

846
00:42:08,280 --> 00:42:11,399
Speaker 1: places that are consistent with the signals you're seeing. Now

847
00:42:11,440 --> 00:42:14,280
Speaker 1: that's not just one place, it's not a unique solution.

848
00:42:14,280 --> 00:42:18,040
Speaker 1: There's still a few ambiguities. There's more than one possible

849
00:42:18,080 --> 00:42:21,239
Speaker 1: location that's consistent with those signals, and then you have

850
00:42:21,239 --> 00:42:23,640
Speaker 1: to figure out which one is yours based on where

851
00:42:23,640 --> 00:42:26,640
Speaker 1: you thought you were recently, and you know other clues.

852
00:42:27,040 --> 00:42:29,440
Speaker 1: I see, you're sort of converting the time stamp of

853
00:42:29,480 --> 00:42:32,000
Speaker 1: these pulses to like using the speed of light to

854
00:42:32,080 --> 00:42:36,680
Speaker 1: kind of tell where you are in terms of space. Yeah, exactly,

855
00:42:36,920 --> 00:42:39,000
Speaker 1: and you don't know exactly how far your way you

856
00:42:39,000 --> 00:42:41,520
Speaker 1: are from the pulsar, you know, like, I'm a certain

857
00:42:41,600 --> 00:42:46,239
Speaker 1: number of beats of this pulsar's pulse away plus a

858
00:42:46,280 --> 00:42:48,920
Speaker 1: little bit, you know, only that extra little bit. And

859
00:42:48,960 --> 00:42:52,760
Speaker 1: so there's lots of different solutions, lots of different possibilities

860
00:42:52,760 --> 00:42:54,840
Speaker 1: for how far you might be away from one pulsar.

861
00:42:55,160 --> 00:42:57,160
Speaker 1: But if you have two or three or four, then

862
00:42:57,200 --> 00:42:59,560
Speaker 1: you can narrow it down. You can say I'm a

863
00:42:59,560 --> 00:43:01,759
Speaker 1: certain from this one, a certain distance from that one.

864
00:43:01,880 --> 00:43:06,400
Speaker 1: It's a harder problem because these pulsars aren't nicely time stamped,

865
00:43:06,520 --> 00:43:08,799
Speaker 1: but people have figured it out, and if you do

866
00:43:08,880 --> 00:43:11,440
Speaker 1: all the mathematics, you can figure out where you are

867
00:43:11,480 --> 00:43:14,759
Speaker 1: in the Solar system to within five kilometers. Wow, that's

868
00:43:14,760 --> 00:43:17,200
Speaker 1: pretty good. That's pretty good. That's better than the two

869
00:43:17,719 --> 00:43:20,480
Speaker 1: from before. Yeah, exactly, it's pretty good. And it works

870
00:43:20,520 --> 00:43:23,319
Speaker 1: all the way across the galaxy, not just within our

871
00:43:23,360 --> 00:43:26,080
Speaker 1: Solar system, so you can be far from even if

872
00:43:26,160 --> 00:43:29,320
Speaker 1: Earth in blodes the nuclear war, you can still figure

873
00:43:29,360 --> 00:43:32,600
Speaker 1: out where you are from these pulsars. Are the pulsars

874
00:43:32,760 --> 00:43:35,960
Speaker 1: distributed all over the galaxy or are we only looking

875
00:43:36,000 --> 00:43:38,760
Speaker 1: at the ones around us. They're distributed across the galaxy.

876
00:43:38,840 --> 00:43:40,840
Speaker 1: People have done a study and they found like fifty

877
00:43:40,920 --> 00:43:44,560
Speaker 1: or sixty good X ray pulsars that are distributed well

878
00:43:44,680 --> 00:43:46,799
Speaker 1: enough across the galaxy that you could use them as

879
00:43:46,880 --> 00:43:50,680
Speaker 1: reference points. And they've actually tried this. They've done it.

880
00:43:50,680 --> 00:43:53,000
Speaker 1: They've built a little one and they fluid on the

881
00:43:53,040 --> 00:43:56,160
Speaker 1: International Space Station and they tried it and it worked. Wow.

882
00:43:56,200 --> 00:43:58,520
Speaker 1: Pretty cool, all right, So it sounds like we do

883
00:43:58,600 --> 00:44:01,400
Speaker 1: have a GPS for the Alexy. We have a galactic

884
00:44:01,480 --> 00:44:04,719
Speaker 1: Pulse source system. You should also call it GPS. It's

885
00:44:04,760 --> 00:44:07,759
Speaker 1: pretty awesome. It's pretty awesome. I love this idea of like,

886
00:44:08,280 --> 00:44:10,800
Speaker 1: you know, astronomers don't get to build what they want.

887
00:44:10,960 --> 00:44:13,200
Speaker 1: They just get to look out there and find stuff

888
00:44:13,239 --> 00:44:16,080
Speaker 1: and use it to be clever to extract the information

889
00:44:16,120 --> 00:44:18,759
Speaker 1: they need. And here's another great example of just like

890
00:44:18,880 --> 00:44:21,319
Speaker 1: making do with what you have. Right, it's almost like

891
00:44:21,360 --> 00:44:24,480
Speaker 1: a nature and the universe made these lighthouses and put

892
00:44:24,520 --> 00:44:27,040
Speaker 1: them all over the galaxy just for us to kind

893
00:44:27,040 --> 00:44:29,960
Speaker 1: of used to get around. Yeah, probably not just for us,

894
00:44:30,120 --> 00:44:32,120
Speaker 1: but it would be a cool science fiction universe where

895
00:44:32,160 --> 00:44:34,840
Speaker 1: we actually visit one of these pulsars and discover, oh,

896
00:44:34,880 --> 00:44:38,960
Speaker 1: they're artificial. Maybe they're part of some billion global positions. Oh,

897
00:44:38,960 --> 00:44:42,759
Speaker 1: it is a lighthouse. It didn't occur naturally, that would

898
00:44:42,760 --> 00:44:45,560
Speaker 1: be pretty awesome. That would be worth some echoes in space.

899
00:44:45,680 --> 00:44:50,880
Speaker 1: Space space space space space cool cool cool. All right, Well,

900
00:44:51,239 --> 00:44:53,440
Speaker 1: I feel a lot better now about Star Wars and

901
00:44:53,520 --> 00:44:57,520
Speaker 1: about other science fiction movies and books. It sounds like

902
00:44:58,160 --> 00:45:00,920
Speaker 1: in the future we could be using these pulsars to

903
00:45:01,040 --> 00:45:02,600
Speaker 1: kind of know where we are in the galaxy and

904
00:45:02,640 --> 00:45:05,279
Speaker 1: to kind of build a map of the entire place. Yeah,

905
00:45:05,440 --> 00:45:08,560
Speaker 1: and as we venture out further and further beyond our

906
00:45:08,560 --> 00:45:11,400
Speaker 1: solar system and try to explore other solar systems, this

907
00:45:11,440 --> 00:45:13,440
Speaker 1: will be a critical way to know where we are

908
00:45:13,560 --> 00:45:16,720
Speaker 1: and hopefully how to come home. Yeah, And so future

909
00:45:16,800 --> 00:45:20,719
Speaker 1: space explorers flying around with their partners and spouses can

910
00:45:21,000 --> 00:45:24,399
Speaker 1: not argue about where they are getting lost, which would

911
00:45:24,400 --> 00:45:26,719
Speaker 1: probably make for a messy divorce out in space. Well,

912
00:45:26,719 --> 00:45:28,920
Speaker 1: they'll probably still argue, like, let's not use that pulsar.

913
00:45:29,000 --> 00:45:34,560
Speaker 1: That one's not reliable. Everybody's using that pulsar. You sound

914
00:45:34,640 --> 00:45:37,480
Speaker 1: like you, You sound like your father. All right. Well,

915
00:45:37,520 --> 00:45:40,439
Speaker 1: I hope that was interesting and gives you a little

916
00:45:40,480 --> 00:45:42,319
Speaker 1: bit more of a sense that we kind of know

917
00:45:42,360 --> 00:45:45,279
Speaker 1: where we are in the universe and the galaxy, and

918
00:45:45,400 --> 00:45:46,839
Speaker 1: that it would be a little bit hard to get

919
00:45:46,880 --> 00:45:49,280
Speaker 1: lost in space. That's right. And this idea of pulsars

920
00:45:49,360 --> 00:45:52,040
Speaker 1: took decades to figure out to narrow down to make

921
00:45:52,080 --> 00:45:55,239
Speaker 1: it work, and it only gives us five kilometer uncertainty.

922
00:45:55,440 --> 00:45:58,520
Speaker 1: Probably somebody out there will have an even better idea

923
00:45:58,760 --> 00:46:00,960
Speaker 1: for how to narrow down our edition. So have that

924
00:46:01,080 --> 00:46:03,359
Speaker 1: idea today so that it's ready for us to use

925
00:46:03,480 --> 00:46:05,560
Speaker 1: in twenty or thirty years. That's right. You don't want

926
00:46:05,560 --> 00:46:07,719
Speaker 1: to miss those snacks, you know. If you miss that

927
00:46:07,800 --> 00:46:11,200
Speaker 1: snack by five kilometers, that's that's not good eating. If

928
00:46:11,239 --> 00:46:13,520
Speaker 1: you learn nothing else today. Remember there are no U

929
00:46:13,600 --> 00:46:17,320
Speaker 1: turns in space or echoes, but there probably are snacks,

930
00:46:18,200 --> 00:46:20,759
Speaker 1: all right. Thanks for joining us, See you next time.

931
00:46:28,960 --> 00:46:31,760
Speaker 1: Thanks for listening, and remember that Daniel and Jorge Explain

932
00:46:31,840 --> 00:46:34,719
Speaker 1: the Universe is a production of I Heart Radio. For

933
00:46:34,840 --> 00:46:37,759
Speaker 1: more podcast for my Heart Radio, visit the I Heart

934
00:46:37,840 --> 00:46:41,480
Speaker 1: Radio Apple Apple Podcasts, or wherever you listen to your

935
00:46:41,520 --> 00:46:42,240
Speaker 1: favorite shows.