Oct. 19, 2025

Dark Matter Dilemmas, Betelgeuse's Fate & the Mysteries of Lagrange Points

Dark Matter Dilemmas, Betelgeuse's Fate & the Mysteries of Lagrange Points

Sponsor Details: This episode is brought to you with the support of NordVPN....enhance your online privacy with the best in the game. To get our special Space Nuts price and bonus deal, visit https://nordvpn.com/spacenuts or use the code SPACENUTS at...

Spotify podcast player badge
Apple Podcasts podcast player badge
Youtube Music podcast player badge
iHeartRadio podcast player badge
Spreaker podcast player badge
PocketCasts podcast player badge
YouTube podcast player badge
Goodpods podcast player badge
Amazon Music podcast player badge
TuneIn podcast player badge
Overcast podcast player badge
JioSaavn podcast player badge
Castro podcast player badge
RSS Feed podcast player badge
Spotify podcast player icon Apple Podcasts podcast player icon Youtube Music podcast player icon iHeartRadio podcast player icon Spreaker podcast player icon PocketCasts podcast player icon YouTube podcast player icon Goodpods podcast player icon Amazon Music podcast player icon TuneIn podcast player icon Overcast podcast player icon JioSaavn podcast player icon Castro podcast player icon RSS Feed podcast player icon
Season 4
Sponsor Details:
This episode is brought to you with the support of NordVPN....enhance your online privacy with the best in the game. To get our special Space Nuts price and bonus deal, visit www.nordvpn.com/spacenuts or use the code SPACENUTS at checkout.
Q&A Edition: Dark Matter, Betelgeuse, and Lagrange Points
In this fascinating episode of Space Nuts, hosts Andrew Dunkley and Professor Jonti Horner tackle a variety of listener questions that delve into the mysteries of the cosmos. From the enigmatic nature of dark matter and its interactions with black holes to the potential explosion of Betelgeuse and the intriguing concept of Lagrange points, this episode is packed with thought-provoking insights and scientific discussions.
Episode Highlights:
- Dark Matter vs. Black Holes: Andrew and Jonti explore the relationship between dark matter and black holes, discussing whether dark matter can be 'eaten' by black holes and the implications of such interactions for our understanding of the universe.
- Betelgeuse's Fate: The hosts address a listener's question about the distance of Betelgeuse and what it means for us if it were to explode. They explain how light travel time affects our perception of cosmic events and the philosophical implications of observing the universe.
- Lagrange Points Explained: Mark's inquiry leads to a detailed explanation of Lagrange points, their stability, and how they function within the gravitational dynamics of celestial bodies. Jonti provides a compelling analogy to help visualize these unique gravitational wells.
- Kordeski Plasma Clouds: The episode wraps up with a discussion on the Kordeski clouds, two large dust clouds located at the Earth-Moon Lagrange points. The hosts delve into their transient nature and the challenges faced in confirming their existence.
For more Space Nuts, including our continuously updating newsfeed and to listen to all our episodes, visit our website. Follow us on social media at SpaceNutsPod on Facebook, X, YouTube Music Music, Tumblr, Instagram, and TikTok. We love engaging with our community, so be sure to drop us a message or comment on your favorite platform.
If you’d like to help support Space Nuts and join our growing family of insiders for commercial-free episodes and more, visit spacenutspodcast.com/about.
Stay curious, keep looking up, and join us next time for more stellar insights and cosmic wonders. Until then, clear skies and happy stargazing.
Got a question for our Q&A episode? https://spacenutspodcast.com/ama

Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts-astronomy-insights-cosmic-discoveries--2631155/support.

 

 

WEBVTT

1
00:00:00.680 --> 00:00:03.359
Hello again, thank you for joining us on Space Nuts

2
00:00:03.480 --> 00:00:06.719
Q and A edition. This is where we answer audience questions,

3
00:00:06.759 --> 00:00:09.039
or at least we read them out and pretend we

4
00:00:09.080 --> 00:00:09.359
know what.

5
00:00:09.279 --> 00:00:09.960
We're talking about.

6
00:00:10.919 --> 00:00:15.160
Today we will be answering questions about dark matter versus

7
00:00:15.160 --> 00:00:18.039
a black hole. It's a titanic struggle.

8
00:00:17.679 --> 00:00:18.399
Who would win.

9
00:00:19.719 --> 00:00:24.120
We are also going to discuss the demise of beetlejuice

10
00:00:24.199 --> 00:00:26.960
or beetlegeis, depending on how you like to pronounce it.

11
00:00:27.760 --> 00:00:32.479
We have a question about lagrange points and the Cordeleski

12
00:00:32.719 --> 00:00:35.200
plasma clouds question has.

13
00:00:35.159 --> 00:00:36.679
Come up from a YouTuber.

14
00:00:37.280 --> 00:00:41.560
We'll deal with all that right now on Space Nuts.

15
00:00:40.960 --> 00:00:49.320
Fifteen second Channel ten nine ignition Squench Space Nuts or

16
00:00:49.840 --> 00:00:52.960
three two.

17
00:00:53.439 --> 00:00:55.000
Space nuts as.

18
00:00:54.880 --> 00:00:56.600
And I reported Neils good.

19
00:00:57.039 --> 00:00:58.200
He's back again for more.

20
00:00:58.320 --> 00:01:00.679
Has done all the research, has all the answers to

21
00:01:00.799 --> 00:01:03.560
all the questions, except for those four. It's Johnny Horner,

22
00:01:03.759 --> 00:01:07.519
professor of astrophysics at the University of Southern Queensland.

23
00:01:07.599 --> 00:01:09.599
Johnny, Hello, I'm good afternoon.

24
00:01:09.640 --> 00:01:10.120
How are you doing.

25
00:01:10.359 --> 00:01:10.920
I'm all right.

26
00:01:10.959 --> 00:01:12.680
How are the renots going at your place?

27
00:01:12.799 --> 00:01:14.599
Well, not too bad. I think they've clocked off for

28
00:01:14.680 --> 00:01:16.280
lunch at the minute, so we might get away with

29
00:01:16.319 --> 00:01:19.000
it on I'm waiting for my other doctor insists I

30
00:01:19.040 --> 00:01:21.280
pay attention to her. Are you yes?

31
00:01:21.519 --> 00:01:24.319
Dogs do that? Yes, indeed they do.

32
00:01:25.959 --> 00:01:29.439
All right, let's answer some questions. Firstly, we've got a

33
00:01:29.519 --> 00:01:33.480
question from Howard. He said, first, I should say that

34
00:01:33.560 --> 00:01:36.439
I think dark matter is going to end up as

35
00:01:36.560 --> 00:01:40.519
a follergiston? Is that the word of our times?

36
00:01:41.400 --> 00:01:43.680
Sorry? Flodgist?

37
00:01:44.079 --> 00:01:46.799
Could be that of our times, a substance dreamed up

38
00:01:46.840 --> 00:01:51.799
to resolve an otherwise unsolvable problem and later discarded as

39
00:01:52.000 --> 00:01:56.000
science advances. But even so, here's my question. Since gravity

40
00:01:56.079 --> 00:01:59.120
seems to be the only force that interacts with dark matter,

41
00:01:59.159 --> 00:02:02.640
what happens when a black hole, the ultimate source of gravity,

42
00:02:02.719 --> 00:02:05.200
comes into contact with dark matter? Does it eat it?

43
00:02:06.120 --> 00:02:08.639
And if so, what happens? And if not, why not?

44
00:02:10.159 --> 00:02:10.319
I do?

45
00:02:10.439 --> 00:02:16.159
We've had questions of similar style and ilk before, and

46
00:02:16.479 --> 00:02:19.319
I can't remember what Fred said, but I think it

47
00:02:19.479 --> 00:02:24.960
said doesn't matter, you know, because dark matter? And yeah,

48
00:02:25.439 --> 00:02:27.879
but I'm sure you've done your homework, because I didn't.

49
00:02:28.639 --> 00:02:31.280
I never did homework as a kid, so why would

50
00:02:31.280 --> 00:02:31.840
I start now?

51
00:02:32.439 --> 00:02:35.879
Well, there seems to be evidence that homework is fairly pointless. Such, yes,

52
00:02:36.759 --> 00:02:38.919
my Apartner's a primary teacher, and you know, I think

53
00:02:38.960 --> 00:02:41.240
if she had her where, kids wouldn't have any homework,

54
00:02:41.280 --> 00:02:44.759
and at least until you're fairly well through secondary school,

55
00:02:45.280 --> 00:02:47.639
it doesn't seem to serve a purpose other than making

56
00:02:48.000 --> 00:02:50.960
some parents feel like their kids are getting properly worked,

57
00:02:51.159 --> 00:02:54.240
you know. So, but onto something that I actually have

58
00:02:54.319 --> 00:02:57.240
expertise in, rather than being talking about teaching what I

59
00:02:57.360 --> 00:03:01.439
clearly done that much, is a real interesting one. It's

60
00:03:02.639 --> 00:03:04.639
I get what you mean with the flogist, and I

61
00:03:04.719 --> 00:03:07.120
think possibly dark energy, i'd argue, is a bit more

62
00:03:07.159 --> 00:03:09.680
of a flogist and thing than that matter at this stage,

63
00:03:10.120 --> 00:03:13.960
because it's very clear that there is mass out there

64
00:03:14.520 --> 00:03:17.680
that it's having an effect but we can't see. And

65
00:03:17.719 --> 00:03:20.840
that's fundamentally what dark matter is. We can add up

66
00:03:21.000 --> 00:03:22.599
all of the mass of all of the things that

67
00:03:22.639 --> 00:03:24.719
we can see in the forms of dust and gas

68
00:03:24.719 --> 00:03:27.199
and stars and all the rest of it, and the

69
00:03:27.199 --> 00:03:30.280
gravitational pull within galaxies, particularly as you get further out

70
00:03:30.319 --> 00:03:34.599
into galaxies, is more significant than can be explained by

71
00:03:34.639 --> 00:03:38.800
the luminous material art and that's where dark matter comes from,

72
00:03:39.240 --> 00:03:41.240
and we see its effects even if we don't see

73
00:03:41.240 --> 00:03:43.719
it in I guess just the same way as back

74
00:03:43.759 --> 00:03:48.199
in the eighteen hundreds, astronomers saw the effects of Uranus

75
00:03:48.800 --> 00:03:52.400
of Neptune's gravity perturbing the orbit of Uranus as it

76
00:03:52.439 --> 00:03:55.879
went round the Sun, and we detected Neptune indirectly. And

77
00:03:55.919 --> 00:03:57.879
then people said, only point you tell it's goope here,

78
00:03:57.919 --> 00:03:59.560
because it must be a planet in this part of

79
00:03:59.560 --> 00:04:02.800
the sky pulling Urinus around and low, and behold, we

80
00:04:02.879 --> 00:04:05.680
found it. And this is fairly fundamental to me as

81
00:04:05.719 --> 00:04:09.240
an exoplanet science person, in that the vast majority of

82
00:04:09.240 --> 00:04:11.639
planets we found around o the cells we found indirectly.

83
00:04:11.680 --> 00:04:15.240
We see a star doing something unexplained, We see it

84
00:04:15.319 --> 00:04:17.759
winking or we see it wobbling, and we in further

85
00:04:17.839 --> 00:04:21.199
presence of a planet as an explanation for that unexplained behavior.

86
00:04:21.680 --> 00:04:23.800
And when you rule out all the other explanations, someone

87
00:04:23.800 --> 00:04:26.000
that's left as a planet, and Bob's your uncle. You've

88
00:04:26.040 --> 00:04:28.279
added one to the Italian. Like we said in the

89
00:04:28.480 --> 00:04:31.000
earlier episode, we've now passed six cells, and so whoopy

90
00:04:31.079 --> 00:04:33.720
for us, we're doing really well. So there's a lot

91
00:04:33.720 --> 00:04:37.680
of evidence that dark matter is a thing, and what

92
00:04:37.839 --> 00:04:40.639
it is nobody really knows. There's been a lot of speculation,

93
00:04:40.800 --> 00:04:42.639
but what seems to be the case is that dark

94
00:04:42.680 --> 00:04:46.160
matter is something that interacts through gravity but doesn't interact

95
00:04:46.199 --> 00:04:48.519
with anything else. It doesn't interact with light. It doesn't

96
00:04:48.560 --> 00:04:52.439
impede light because we see dust blots light, so dust

97
00:04:52.519 --> 00:04:56.480
is not dark matter. So what happens, Well, if dark

98
00:04:56.560 --> 00:04:59.639
matter interacts with gravity in just the same way as

99
00:04:59.680 --> 00:05:02.519
normal matter, then it will interact with a black hole

100
00:05:02.680 --> 00:05:05.160
in almost the same way as normal matter. And they

101
00:05:05.240 --> 00:05:07.600
almost said a little asterisk. I'll come to in a minute.

102
00:05:07.680 --> 00:05:10.600
What that means is that if something gets close enough

103
00:05:10.600 --> 00:05:13.480
to a black hole to be within its event horizon,

104
00:05:14.040 --> 00:05:16.160
then that means it would have to travel faster than

105
00:05:16.160 --> 00:05:18.480
the speed of light to escape from the gravitational pull

106
00:05:18.519 --> 00:05:21.160
of the black hole. So it's effectively been nombed. And

107
00:05:21.160 --> 00:05:23.319
you've got black holes being the pack man of the

108
00:05:23.399 --> 00:05:26.839
universe that just go around gobbling everything up. Once it

109
00:05:26.920 --> 00:05:29.560
is gobbled up, it doesn't matter if it's dark matter

110
00:05:29.800 --> 00:05:32.519
or normal matter. It's been nombed and it just adds

111
00:05:32.560 --> 00:05:34.319
to the mass of the black hole. And I guess

112
00:05:34.360 --> 00:05:35.759
the black hole is a bit like the ball, and

113
00:05:35.759 --> 00:05:39.000
it's your individuality. Indistinctiveness has been added to our own

114
00:05:39.360 --> 00:05:41.680
and the dark matter has been nombed in just the

115
00:05:41.720 --> 00:05:44.040
same way it would have been with normal matter. So

116
00:05:44.120 --> 00:05:47.759
from that point of view, there is actually no problem.

117
00:05:48.000 --> 00:05:51.639
We'd expect dark matter to be eaten and to stay eaten.

118
00:05:52.759 --> 00:05:55.519
There are suggestions that the supermassive black holes like the

119
00:05:55.519 --> 00:05:58.000
one we've got at the middle of the Milky Way

120
00:05:58.639 --> 00:06:01.720
are only able to be formed if that matter exists,

121
00:06:02.680 --> 00:06:07.879
and even more normal mass black holes have a restriction

122
00:06:08.000 --> 00:06:11.519
on the amount that they can eat. It's almost like

123
00:06:11.560 --> 00:06:14.399
the celestial equivalent of a gastric band or something like that.

124
00:06:14.439 --> 00:06:17.720
It's something called the Eddington limit. Material falling into a

125
00:06:17.759 --> 00:06:21.199
black hole, that is normal matter as it falls in

126
00:06:22.120 --> 00:06:25.720
gets accelerated, gets heated up in its light. And if

127
00:06:25.759 --> 00:06:28.079
you've got a black hole eating a lot of stuff,

128
00:06:28.439 --> 00:06:31.439
there's a lot of material falling and emitting incredible aunts

129
00:06:31.480 --> 00:06:34.480
of radiation. They can essentially push away or the matter

130
00:06:34.560 --> 00:06:37.879
around the black hole and force it to stop eating,

131
00:06:38.399 --> 00:06:41.240
effectively putting a limit on the amount that it can

132
00:06:41.360 --> 00:06:45.319
devour at any given time. And you do get things

133
00:06:45.319 --> 00:06:49.360
that are eating at what's called super Eddington rates, but

134
00:06:49.480 --> 00:06:53.160
that's where something's essentially pushing material in so quickly that

135
00:06:53.279 --> 00:06:56.439
it overcomes that effect. So I guess it's a bit

136
00:06:56.560 --> 00:06:58.639
like saying you can only drink so much water because

137
00:06:58.639 --> 00:07:00.879
you can only swallow so much. But if somebody shoves

138
00:07:00.879 --> 00:07:02.560
a fire hose in your mouth, the water's going to

139
00:07:02.639 --> 00:07:07.240
go somewhere. That's kind of that situation. But that puts

140
00:07:07.240 --> 00:07:10.399
a limit on how much a black hole can eat

141
00:07:10.439 --> 00:07:12.600
at a given time. At the pace at which can

142
00:07:12.639 --> 00:07:17.279
devour matter, dark matter doesn't interact with like al radiation

143
00:07:17.480 --> 00:07:19.959
or anything like that, so the Eddington limit doesn't apply

144
00:07:20.879 --> 00:07:23.759
because a black hole shining like a searchlight will not

145
00:07:23.839 --> 00:07:27.560
impede the motion of dark matter one little bit. And

146
00:07:27.600 --> 00:07:30.040
so there is an idea that actually dark matter is

147
00:07:30.079 --> 00:07:33.519
a more effective food for black holes and normal matter

148
00:07:34.199 --> 00:07:38.000
because dark matter circumvents the Gasrick band. It circumvents this

149
00:07:38.160 --> 00:07:42.439
Eddington limit that prevents a black hole from eating to excess,

150
00:07:43.000 --> 00:07:45.319
and that may actually have been a significant part of

151
00:07:45.399 --> 00:07:47.560
how the supermassive black holes that we get in the

152
00:07:47.560 --> 00:07:51.279
middle of galaxies actually got their start where they got

153
00:07:51.279 --> 00:07:55.199
their start aided by dark matter. And so it's a

154
00:07:55.199 --> 00:07:57.240
really interesting question because I had not really thought of

155
00:07:57.279 --> 00:07:59.879
this until Howard's question. Came through and added a bit

156
00:07:59.879 --> 00:08:04.040
of reading around. But it's actually one of these scenarios

157
00:08:04.120 --> 00:08:07.680
where dark matter, it seems, is a help to black

158
00:08:07.720 --> 00:08:11.560
holes rather than a hindrance, and therefore may help to

159
00:08:11.600 --> 00:08:13.439
explain why the universe is and where that we see

160
00:08:13.439 --> 00:08:17.480
it today, beyond just explaining the rotation curves of galaxies

161
00:08:17.480 --> 00:08:19.800
and things like this, which is why it was hypothesized

162
00:08:19.800 --> 00:08:20.560
in the first place.

163
00:08:20.879 --> 00:08:24.439
Okay, so you do believe there's interaction between dark matter

164
00:08:24.480 --> 00:08:25.920
and black holes.

165
00:08:25.800 --> 00:08:30.040
Of course, Yeah, and sorry, of course the sounds to dismissive.

166
00:08:30.120 --> 00:08:33.320
The reason that it's in, of course, is that dark

167
00:08:33.360 --> 00:08:37.919
matter interacts with gravity. That's fundamentally how we found it

168
00:08:37.960 --> 00:08:41.639
in the first place. And therefore, if it falls into

169
00:08:41.679 --> 00:08:43.840
a black hole, it behaves like any other kind of

170
00:08:43.840 --> 00:08:45.440
matter from the point of view gravity.

171
00:08:46.240 --> 00:08:47.879
And so therefore, and I.

172
00:08:47.799 --> 00:08:50.039
Mean, there are some suggestions that black holes are a

173
00:08:50.120 --> 00:08:52.639
significant component of dark matter.

174
00:08:53.000 --> 00:08:55.039
Yes, we can only see them when they're feeding.

175
00:08:55.639 --> 00:08:57.960
If they're not eating anything, we have no indication of

176
00:08:58.000 --> 00:08:59.960
black holes there other than its effect on the mass

177
00:09:00.080 --> 00:09:02.679
around it. You know, light gets bent around it and

178
00:09:02.720 --> 00:09:06.080
all the rest of it. Yeah, some component of dark

179
00:09:06.159 --> 00:09:08.480
matter may well be primordial black holes. That's one of

180
00:09:08.480 --> 00:09:09.000
a suggestion.

181
00:09:09.559 --> 00:09:11.519
Yeah, there's still so much to learn. We don't know

182
00:09:11.600 --> 00:09:15.240
much at all, although they also I think if I

183
00:09:15.279 --> 00:09:22.159
recall correctly say that dark matter clusters in around galaxies

184
00:09:22.200 --> 00:09:28.200
and around concentrated points, it's much thinner where the universe

185
00:09:28.279 --> 00:09:28.799
is emptier.

186
00:09:28.879 --> 00:09:29.399
Is that right?

187
00:09:30.080 --> 00:09:31.799
And that kind of makes sense as well, because if

188
00:09:31.879 --> 00:09:34.759
dark matter is feeling the effects of gravity like everything else,

189
00:09:35.320 --> 00:09:37.360
the same things that would have pulled an excess of

190
00:09:37.759 --> 00:09:41.879
visible matter together to farm galaxies would have brought together dark.

191
00:09:41.679 --> 00:09:42.159
Matter as well.

192
00:09:42.200 --> 00:09:45.279
And there is this discussion that galaxies have dark matter

193
00:09:45.320 --> 00:09:48.799
halos around them. So the rotation curves of galaxies are

194
00:09:48.840 --> 00:09:52.679
evidence for dark matter within those galaxies, meaning that there

195
00:09:52.720 --> 00:09:55.320
is more mass interior to a certain distance from the

196
00:09:55.320 --> 00:09:57.279
middle of the galaxy than we can account for by

197
00:09:57.320 --> 00:10:01.039
what we see. That means that together rotation happening quicker

198
00:10:01.080 --> 00:10:03.679
because it's more master left on, more gravitational pulse or

199
00:10:03.720 --> 00:10:07.639
faster rotation. But the massive galaxy clusters, in terms of

200
00:10:07.639 --> 00:10:10.080
how the galaxies are interacting with each other and how

201
00:10:10.120 --> 00:10:14.240
they're moving within the clusters, the mass within the cluster

202
00:10:14.759 --> 00:10:17.240
has to been bigger than the masters that the galaxies

203
00:10:17.279 --> 00:10:20.840
seem to have from the visible material, even accounting for

204
00:10:20.879 --> 00:10:23.759
the dark matterrhithm causing their rotation speeds to be higher.

205
00:10:24.120 --> 00:10:27.200
And that's suggesting that that matter is also in a

206
00:10:27.240 --> 00:10:30.559
halo around the galaxy, given that galaxy even more muster

207
00:10:30.679 --> 00:10:31.080
even more.

208
00:10:32.679 --> 00:10:34.480
Yes, it is so fascinating.

209
00:10:35.000 --> 00:10:38.799
And Flogiston was a hypothetical fire like element once thought

210
00:10:38.840 --> 00:10:42.399
to be contained within combustible bodies and released during combustion,

211
00:10:42.559 --> 00:10:47.799
a theory proposed by Johann Beecher, and it's an outdated

212
00:10:47.840 --> 00:10:53.279
theory that was eventually disproved by Antoine Levosier through his

213
00:10:53.360 --> 00:10:56.919
experience with oxygen, which demonstrated that burning is a chemical

214
00:10:56.960 --> 00:11:00.519
reaction involving the combination of a substance with oxyde, not

215
00:11:00.639 --> 00:11:05.480
the release of flogiston. There you are, all right, Howard,

216
00:11:05.519 --> 00:11:09.840
Thank you so much for a great question. Let's take

217
00:11:09.919 --> 00:11:12.200
a break from the show to tell you about our sponsor,

218
00:11:12.279 --> 00:11:16.480
nord VPN, and we're very proud to have partnered with

219
00:11:16.600 --> 00:11:21.480
NordVPN so that we can get you more secure online

220
00:11:21.720 --> 00:11:23.720
no matter what you do, where you are, or how

221
00:11:23.759 --> 00:11:25.840
you do it. Now, if you sign up for two

222
00:11:25.879 --> 00:11:30.039
year NordVPN plan using the code word space nuts, you'll

223
00:11:30.080 --> 00:11:34.399
receive four extra months absolutely free. That's twenty eight months

224
00:11:34.399 --> 00:11:38.320
of top tier VPN protection at a fraction of the cost.

225
00:11:39.279 --> 00:11:42.399
With NordVPN, what you get is access to over seven

226
00:11:42.879 --> 00:11:48.720
seven hundred servers worldwide, ultra fast connections, advanced features like

227
00:11:48.919 --> 00:11:53.480
threat protection pro and mesh Net, and secure usage for

228
00:11:53.639 --> 00:11:57.639
up to ten devices simultaneously, so you're pretty well covered.

229
00:11:57.759 --> 00:12:00.720
You have to admit now, and this is a great

230
00:12:00.720 --> 00:12:03.039
opportunity and if you'd like to take advantage of it,

231
00:12:03.360 --> 00:12:06.879
visit nord vpn dot com slash space nuts to claim

232
00:12:06.919 --> 00:12:11.879
your exclusive offer today. And remember, with nordvpn's thirty day

233
00:12:11.879 --> 00:12:15.720
money back guarantee, it's risk free. It's a great investment,

234
00:12:16.120 --> 00:12:19.799
a small price to pay for your online security and privacy.

235
00:12:20.360 --> 00:12:25.240
Stay secure, stay connected, and keep exploring the cosmos with confidence.

236
00:12:25.799 --> 00:12:31.480
NordVPN dot com slash space nuts, NordVPN dot com slash

237
00:12:31.639 --> 00:12:35.000
space nuts and don't forget the code words space nuts

238
00:12:35.039 --> 00:12:35.679
at the checkout.

239
00:12:36.320 --> 00:12:38.000
Now back to the show.

240
00:12:38.799 --> 00:12:45.639
Three space nuts now. Gary is next. He's a fan

241
00:12:45.759 --> 00:12:49.720
from Canada's East Coast. I was only recently on Canada's

242
00:12:49.759 --> 00:12:54.039
East Coast, visited Peggy's Cove and Halifax and lovely part

243
00:12:54.039 --> 00:12:56.919
of the world. He goes on to say, I enjoy

244
00:12:56.960 --> 00:13:00.519
your humor mixed with actual scientific knowledge out of part's

245
00:13:00.519 --> 00:13:04.240
probably not anyway. Question, can you tell me if beetlejuice

246
00:13:04.279 --> 00:13:08.360
Beetlegeiss explodes six hundred and eighty million light years away,

247
00:13:08.519 --> 00:13:12.000
whether we are just seeing something that happened six hundred

248
00:13:12.039 --> 00:13:15.919
and eighty million years ago, traveling at the speed of light.

249
00:13:17.519 --> 00:13:20.279
It's a really good question. It comes a plot when

250
00:13:20.320 --> 00:13:24.519
I'm doing outreach and stuff like that. Beetlejuice is depending

251
00:13:24.559 --> 00:13:27.639
on whose measurements you expect, it's not quite six hundred

252
00:13:27.639 --> 00:13:29.799
and eighty million light years away. It's somewhere between about

253
00:13:29.840 --> 00:13:32.559
five hundred and seven hundred light years away, so it's

254
00:13:32.600 --> 00:13:35.919
a bit closer to home than that. But the question

255
00:13:36.000 --> 00:13:39.840
still stands. When we see objects in the universe, we

256
00:13:39.879 --> 00:13:43.320
see them as they were when the light was emitted

257
00:13:43.360 --> 00:13:46.840
from them, and that's even true for the rumor around you.

258
00:13:47.159 --> 00:13:50.039
It's just that everything nearby is cell class that you're

259
00:13:50.039 --> 00:13:54.440
effectively seeing instantaneously. Light travels at three hundred thousand kilometers

260
00:13:54.440 --> 00:13:57.240
a second, so we see the moon, which is about

261
00:13:57.279 --> 00:14:00.679
three hundred and eighty four thousand kilometers away, worrying. We

262
00:14:00.799 --> 00:14:02.919
just had all the fuss about the supermoon's yet again.

263
00:14:03.000 --> 00:14:05.000
So the distance to the Moon does very a little bit,

264
00:14:05.559 --> 00:14:09.320
but that means we see the Moon using light that

265
00:14:09.440 --> 00:14:11.480
reflected off the surface of the Moon about one and

266
00:14:11.600 --> 00:14:14.360
one third seconds ago. It's one and one third light

267
00:14:14.440 --> 00:14:17.320
seconds away. We see the Sun with light that left

268
00:14:17.320 --> 00:14:20.000
the surface of the photosphere a bit more than eight

269
00:14:20.000 --> 00:14:23.320
minutes ago. And so when you see anything, you're seeing

270
00:14:24.000 --> 00:14:27.720
light that left a period of time ago. You see

271
00:14:27.720 --> 00:14:29.960
everything as it was in the past, rather than as

272
00:14:30.000 --> 00:14:32.759
it would be in a perverse now that if you

273
00:14:32.759 --> 00:14:36.559
could teleport there instantaneously, it would look different. I mean

274
00:14:36.559 --> 00:14:39.120
that brings into question could you teleport at faster than

275
00:14:39.159 --> 00:14:40.840
the speed of light? But then the question is kind

276
00:14:40.840 --> 00:14:44.200
of teleport anyway, So that's getting getting into the grounds

277
00:14:44.200 --> 00:14:50.879
of science fiction. But it brings open a odd philosophical

278
00:14:51.000 --> 00:14:54.240
kind of question, which is what do you define as

279
00:14:54.279 --> 00:14:59.200
something happening now? Do you define them now as a

280
00:14:59.279 --> 00:15:02.919
perceived now where you are, or do you find now

281
00:15:02.960 --> 00:15:06.799
as being the time that the event happens, that the

282
00:15:06.879 --> 00:15:09.759
light would reach you once it has traveled that business

283
00:15:09.759 --> 00:15:12.080
to get to you. And I'm explaining that badly. But

284
00:15:12.799 --> 00:15:15.919
this is essentially the fundamental of the question. If Beetlejuice

285
00:15:16.639 --> 00:15:21.200
exploded a thousand years ago, on that light reaches as say,

286
00:15:21.639 --> 00:15:23.440
three hundred years in the future, So it turns out

287
00:15:23.480 --> 00:15:27.399
it was seven hundred light years away. Beetlejuice exploded a

288
00:15:27.480 --> 00:15:30.519
thousand years ago, the light travels for seven hundred years,

289
00:15:30.559 --> 00:15:33.000
so it all reaches in three hundred years seven. I'm

290
00:15:33.039 --> 00:15:36.039
sure my head has got flipped over there somewhere. But

291
00:15:36.840 --> 00:15:38.960
on if Beetlejuice exploded a thousand years ago, we saw

292
00:15:38.960 --> 00:15:40.720
it three hundred years in the future, then that'd be

293
00:15:40.720 --> 00:15:43.440
thirteen hundred light years away. That's I'm going the wrong way.

294
00:15:43.480 --> 00:15:46.120
But anyway, we know, if you have exploded in the past,

295
00:15:46.639 --> 00:15:49.480
we see it at some point in the future. Did

296
00:15:49.480 --> 00:15:51.919
that explosion happen in the past of the future? Well,

297
00:15:52.159 --> 00:15:55.000
in Beetlejuice's frame of reference, if you were stood camping

298
00:15:55.759 --> 00:15:58.519
near Beetlejuice, you would have seen it in the past.

299
00:15:59.240 --> 00:16:02.279
You'd have seen it happen already. But any signal you

300
00:16:02.360 --> 00:16:04.600
sent to tell us that it had have happened would

301
00:16:04.600 --> 00:16:06.840
only just arrive at the same time that the explosion did,

302
00:16:07.320 --> 00:16:08.879
because you'd have to see it first, and then the

303
00:16:08.919 --> 00:16:11.559
signal back. So from the point of view of us

304
00:16:11.559 --> 00:16:15.360
here on Earth, when does beetlejuice explode? Is it when

305
00:16:15.360 --> 00:16:18.799
we see it or when we calculate back how long

306
00:16:18.840 --> 00:16:21.200
ago that explosion had to happen for us to see

307
00:16:21.240 --> 00:16:24.600
it today. And it's where we get into the philosophy

308
00:16:24.639 --> 00:16:28.200
of perception and what it actually means to be now,

309
00:16:28.960 --> 00:16:31.720
because everything around us, even the tip of my own nose,

310
00:16:31.799 --> 00:16:34.679
is far enough away that I'm seeing it in the past.

311
00:16:35.279 --> 00:16:37.320
I mean, I'm seeing it in the past by nane

312
00:16:37.360 --> 00:16:42.240
oh seconds, but it's still in the past. And so

313
00:16:42.399 --> 00:16:45.559
there's a weird bit of internal philosophy that has to

314
00:16:45.600 --> 00:16:47.200
go on there that is driven by the size of

315
00:16:47.240 --> 00:16:51.159
the universe. And we came up with this fine with sound.

316
00:16:51.279 --> 00:16:53.279
We see a flash of lightning and then we hear

317
00:16:53.320 --> 00:16:55.399
a rumble of thunder a certain amount of time later,

318
00:16:56.279 --> 00:16:58.639
and we're aware that the two events happened at the

319
00:16:58.679 --> 00:17:01.440
same time, but the sound takes a certain amount of

320
00:17:01.480 --> 00:17:04.160
time to reach us. So if we imagine that there

321
00:17:04.200 --> 00:17:07.720
was some form of instantaneous communication that could happen that

322
00:17:07.759 --> 00:17:10.720
happened faster than the speed of light, and we were

323
00:17:10.720 --> 00:17:14.319
able to have a real ay near beetlejuice. Tellers, beetlejuice

324
00:17:14.359 --> 00:17:16.079
has now gone back, you will see it in seven

325
00:17:16.160 --> 00:17:19.519
hundred years time. Then it makes sense to say that

326
00:17:19.559 --> 00:17:21.680
beetlejuice ex blooded in the past and we only see

327
00:17:21.720 --> 00:17:25.200
it now. But from your perception point of view, you'd

328
00:17:25.200 --> 00:17:27.519
see it happening now when you saw it happen now,

329
00:17:27.640 --> 00:17:30.960
and that will be all now. And so this is

330
00:17:31.319 --> 00:17:35.640
a really fun question because the reality is that it's

331
00:17:35.799 --> 00:17:39.119
all to do with frames of reference and where you stand.

332
00:17:40.119 --> 00:17:43.559
And yeah, I'm listening to a fairly pulpy science fiction

333
00:17:43.839 --> 00:17:47.000
series at the minute called Expeditionary Force that actually talks

334
00:17:47.000 --> 00:17:49.799
about how slow light is when you're having combat happening

335
00:17:49.799 --> 00:17:53.240
in space. You know, if you're shooting lasers and mazers

336
00:17:53.279 --> 00:17:55.480
that people neural lights second away from them. By the

337
00:17:55.480 --> 00:17:58.319
time your laser gets there, they'll have moved, so you've

338
00:17:58.359 --> 00:18:00.160
got to shoot whether going to be not whether they

339
00:18:00.160 --> 00:18:02.480
actually are, but then they know that, so they're dodging.

340
00:18:03.200 --> 00:18:05.920
And the further away you are, the longer it takes

341
00:18:05.920 --> 00:18:07.359
for the light to reach you. So you've got the

342
00:18:07.480 --> 00:18:10.559
bisarre thing of if you can jump through space and

343
00:18:10.759 --> 00:18:12.599
you can go through a wormhole and pay someone else.

344
00:18:12.599 --> 00:18:14.440
You could fight someone and then jump through space and

345
00:18:14.480 --> 00:18:17.000
watch the battle happen and watch yourself fight them.

346
00:18:17.279 --> 00:18:17.599
Wow.

347
00:18:17.920 --> 00:18:20.880
And this is where all the philosophy starts to mess

348
00:18:20.920 --> 00:18:23.640
with your head. But it makes for wonderful science fiction

349
00:18:23.759 --> 00:18:26.960
scenarios so long as you build something into your science

350
00:18:27.000 --> 00:18:29.039
fiction world that allows you to have faster than light

351
00:18:29.119 --> 00:18:31.799
travel so you can get ahead of the images of

352
00:18:31.839 --> 00:18:33.319
yourself doing a certain thing.

353
00:18:34.680 --> 00:18:37.400
That is really interesting. I love science fiction for that

354
00:18:37.480 --> 00:18:39.839
reason because you can just make all this stuff happen

355
00:18:39.920 --> 00:18:43.240
that it is not yet achievable as far as we know.

356
00:18:43.839 --> 00:18:45.640
There must be is our example. So that when I

357
00:18:45.720 --> 00:18:48.319
was young, I remember the Anne McCaffrey novels really well.

358
00:18:48.319 --> 00:18:50.680
And you know, she was most famous across for the

359
00:18:51.079 --> 00:18:55.039
Dragons series. You know, all the books about people in

360
00:18:55.079 --> 00:18:56.920
a world where they live and bond with dragons and

361
00:18:56.960 --> 00:18:58.720
they burned thread from the end, it turns out that

362
00:18:58.759 --> 00:19:01.000
it's actually a soft sci fi setting rather than a

363
00:19:01.000 --> 00:19:04.400
fantasy setting because reasons you find further down the series.

364
00:19:04.920 --> 00:19:07.000
But she also had a series of books about the

365
00:19:07.000 --> 00:19:10.519
Talents of Earth, which were these people with psychokinetic and

366
00:19:10.880 --> 00:19:14.440
telepathic talents who could transport things using the power of

367
00:19:14.440 --> 00:19:16.119
the mind from one place to one other, and they

368
00:19:16.119 --> 00:19:20.519
could communicate telekinetically. And of course what you do with

369
00:19:20.559 --> 00:19:22.480
people like that in Aan McCaffrey's world is not turn

370
00:19:22.559 --> 00:19:24.720
them into soldiers and warriors like Marvel or the X

371
00:19:24.759 --> 00:19:26.079
Men would do it, but you turn them into the

372
00:19:26.079 --> 00:19:29.839
postal service, and the people effectively become the method by

373
00:19:29.839 --> 00:19:32.400
which we send people to other stars. And if you're

374
00:19:32.440 --> 00:19:35.680
a powerful enough telekinetic, you can pick something up on

375
00:19:35.720 --> 00:19:38.359
Earth and send it to Capella and it'll appear there.

376
00:19:39.319 --> 00:19:41.599
But then they had really powerful telescopes, and they have

377
00:19:41.640 --> 00:19:43.720
had to be really powerful telescopes the first time they

378
00:19:43.759 --> 00:19:46.599
tried sending things to another star, and they'll look at

379
00:19:46.599 --> 00:19:49.880
that start and psychic person goes wibily wobbly, whibly wobbly,

380
00:19:49.960 --> 00:19:52.319
and the thing disappears, and then it appears x to Capella,

381
00:19:52.960 --> 00:19:55.359
and that's all well and good until somebody points out

382
00:19:55.359 --> 00:19:57.960
the fact that the light was seeing from Capella left

383
00:19:58.000 --> 00:20:01.240
it thirty years ago and we've just seen that thing arrive,

384
00:20:01.400 --> 00:20:05.279
so they've obviously teleported it back through time. And then

385
00:20:05.279 --> 00:20:07.400
you end up with this bizarre world where you've got

386
00:20:07.400 --> 00:20:11.079
this web of world's vast distances from each other that

387
00:20:11.160 --> 00:20:16.160
are linked by these postal service workers effectively, who can

388
00:20:16.519 --> 00:20:21.200
from an instant communication instant transportation. But in order to

389
00:20:21.240 --> 00:20:23.720
have it the instant and to maintain the current, now

390
00:20:24.160 --> 00:20:26.960
they've had to send things back in time. But that

391
00:20:26.960 --> 00:20:28.480
that means if they send them back in time, but

392
00:20:28.519 --> 00:20:32.000
they can communicate instantaneously in both directions, could they tell

393
00:20:32.039 --> 00:20:34.119
you thirty years ago to not send them.

394
00:20:34.440 --> 00:20:42.079
Yeah, it's a similar story in terms of the Dune

395
00:20:42.319 --> 00:20:44.440
sci fi series, because same thing.

396
00:20:44.480 --> 00:20:49.160
They fold space, so you can go instantly from one

397
00:20:49.200 --> 00:20:55.799
planet to Dune. But it's based on what you just said,

398
00:20:55.839 --> 00:20:57.519
that's not the case. They'd have to be going back

399
00:20:57.559 --> 00:20:58.400
in time as well.

400
00:20:58.759 --> 00:21:01.519
Yeah, and the un stuff got that part right. But

401
00:21:01.559 --> 00:21:03.920
then you do have that thing of if it can

402
00:21:03.960 --> 00:21:07.720
communicate instantaneously both ways, then you're communicating back in time

403
00:21:07.799 --> 00:21:10.799
by thirty years. But if they then looked back at Earth,

404
00:21:10.880 --> 00:21:13.160
they would see Earth as it was sixty years earlier,

405
00:21:13.599 --> 00:21:16.759
except thirty years back in time. Looking back thirty years,

406
00:21:17.599 --> 00:21:20.440
it strikes me that with big enough telescopes that would

407
00:21:20.759 --> 00:21:22.839
I mean, it's a science fiction world, so we've already

408
00:21:22.839 --> 00:21:26.079
broken the laws of physics. But you would make detective

409
00:21:26.119 --> 00:21:28.920
work and police work totally redundant, because what you do

410
00:21:29.039 --> 00:21:31.279
is you'd say there was a crime last night, Right,

411
00:21:31.319 --> 00:21:35.359
we'll teleport someone fourteen hours away so they're looking back

412
00:21:35.400 --> 00:21:37.359
twenty eight hours, so they can just look back and

413
00:21:37.400 --> 00:21:38.200
see what happened.

414
00:21:38.680 --> 00:21:42.920
Yes, yeah, it makes I love I love it.

415
00:21:43.440 --> 00:21:47.079
I love these impossible scenarios.

416
00:21:47.119 --> 00:21:49.960
But you know, one day they might come up with

417
00:21:50.000 --> 00:21:52.599
a way of doing some weird stuff that we can't

418
00:21:52.640 --> 00:21:56.039
explain today, and there'll be some logic attached to it.

419
00:21:56.119 --> 00:21:58.279
But I'm sure if we were podcasting one hundred and

420
00:21:58.359 --> 00:22:00.559
twenty five years ago, people will come so he couldn't

421
00:22:00.599 --> 00:22:03.720
have a heavier heavier than their flight, and look how

422
00:22:03.720 --> 00:22:04.359
that worked out.

423
00:22:04.640 --> 00:22:09.359
Yeah, exactly, all right, Thank you Gary. Hopefully we covered

424
00:22:09.400 --> 00:22:12.119
that question for you. This is Space Nets with Andrew

425
00:22:12.160 --> 00:22:17.240
Dunkley and John y Jonna. Okay, we take all for

426
00:22:19.119 --> 00:22:23.480
space Nuts. Next question, Oh, we're still in Canada. This

427
00:22:23.680 --> 00:22:25.839
question comes from Mark.

428
00:22:26.759 --> 00:22:31.359
Hi. It's Mark in London and Canada. I'm current listening

429
00:22:31.519 --> 00:22:36.000
to all the back episodes, so I'm in March twenty

430
00:22:36.359 --> 00:22:39.359
twenty one, so if you answer my question, it might

431
00:22:39.359 --> 00:22:42.319
take me a while to hear it. But I was

432
00:22:42.319 --> 00:22:46.200
wondering about lagrange points and the way they're describe as

433
00:22:46.200 --> 00:22:50.680
a gravitational well, and we can send satellites there to

434
00:22:51.079 --> 00:22:52.319
orbit around them.

435
00:22:52.880 --> 00:22:55.000
Is there a way to.

436
00:22:54.319 --> 00:22:58.559
Define the mass of the lagrange point? Like, obviously there's

437
00:22:58.599 --> 00:23:01.839
nothing there, it doesn't atch you have a mass, but

438
00:23:01.960 --> 00:23:06.759
we define or we observe things orbiting, and we can

439
00:23:06.759 --> 00:23:09.119
define the mass of all those objects. So when you

440
00:23:10.400 --> 00:23:13.480
see a satellite or design a satellite to go into

441
00:23:13.599 --> 00:23:17.920
orbit around a lagrange point, is there an equivalent mass

442
00:23:18.640 --> 00:23:23.799
that it's orbiting. That's obviously created by the whole system

443
00:23:23.839 --> 00:23:28.480
of the larger objects, But is that does that mass?

444
00:23:28.960 --> 00:23:32.440
Is it definable? Thanks Gat, Thank you Mark.

445
00:23:32.480 --> 00:23:36.200
So Mark's actually demonstrating time travel. He's listening to us

446
00:23:36.200 --> 00:23:38.200
in the past, but we're hearing him today.

447
00:23:39.079 --> 00:23:40.720
I was just thinking of that. So the question is

448
00:23:40.759 --> 00:23:43.440
when Mark listens to this answer, is he listening to

449
00:23:43.480 --> 00:23:45.400
in twenty twenty five or twenty twenty nine.

450
00:23:46.000 --> 00:23:51.920
H's that's a good point, very interesting, and yeah, thanks

451
00:23:51.960 --> 00:23:55.440
for the question, Mark. So we're looking at lagrange points.

452
00:23:55.480 --> 00:23:58.559
Our next question actually kind of focuses on that as well.

453
00:23:59.359 --> 00:24:04.039
Lagrange point points, gravitation wheels, the mess of a lagarage

454
00:24:04.039 --> 00:24:06.000
point I think was the gats of his question.

455
00:24:06.640 --> 00:24:09.319
And it's a really interesting question. In fact, I've got

456
00:24:09.359 --> 00:24:11.880
a pH d student, part time student working with me

457
00:24:11.920 --> 00:24:14.039
who asked a very similar question a couple of months ago,

458
00:24:14.480 --> 00:24:16.279
because he's going to be working and looking at the

459
00:24:16.319 --> 00:24:18.839
Nettune Trojans, which are trapped around the L four and

460
00:24:18.920 --> 00:24:21.119
L five O the grand points of Neptune, and they're

461
00:24:21.160 --> 00:24:25.039
library around following this kind of kidney shaped path over

462
00:24:25.079 --> 00:24:28.279
a period of hundreds of years around this point sixty

463
00:24:28.319 --> 00:24:29.720
degrees ahead or behind Neptune.

464
00:24:29.759 --> 00:24:30.359
And it so, but.

465
00:24:31.960 --> 00:24:35.400
What's going on here is, well, take a little bit

466
00:24:35.400 --> 00:24:36.759
of a deeto. When I was a kid, I was

467
00:24:36.759 --> 00:24:39.359
a member of the Scouts, and me too. When you

468
00:24:39.359 --> 00:24:41.759
were in the Scouts and you went walking around the countryside,

469
00:24:41.799 --> 00:24:44.160
you had an Ordermance survey map. And I don't know

470
00:24:44.200 --> 00:24:46.000
if that's called the same thing overseas, but that's what

471
00:24:46.039 --> 00:24:48.960
it was in the UK. And what this map had

472
00:24:49.240 --> 00:24:51.400
was a map of all the roads and all the

473
00:24:51.440 --> 00:24:52.960
hills and all the rest of it, but drawn on

474
00:24:53.000 --> 00:24:56.200
it were contours, and all points on a given contour

475
00:24:56.279 --> 00:24:57.200
were the same height.

476
00:24:57.039 --> 00:24:58.519
Above sea level yep.

477
00:24:58.880 --> 00:25:00.480
And so you could tell how told the hills will

478
00:25:00.519 --> 00:25:02.279
how seep the valleys where all the rest of it.

479
00:25:03.119 --> 00:25:07.119
What those maps actually are are maps of gravitational potential.

480
00:25:08.200 --> 00:25:10.480
So all objects at the same distance from the center

481
00:25:10.519 --> 00:25:12.480
of the Earth have the same gravitational potential, and you

482
00:25:12.559 --> 00:25:15.880
join them up with a contour that's exactly the same thing.

483
00:25:16.000 --> 00:25:20.480
So if you make a hypothetical simplified solar system where

484
00:25:20.519 --> 00:25:22.599
you just have the Earth while the Earth and the

485
00:25:22.599 --> 00:25:26.160
Moon's mush into one and the Sun and nothing else,

486
00:25:26.880 --> 00:25:29.720
you can make a contour map where you measure where

487
00:25:29.759 --> 00:25:33.359
you calculate the gravitational potential every location in the solar system,

488
00:25:34.000 --> 00:25:36.079
and then you do the same kind of map. You

489
00:25:36.319 --> 00:25:40.079
join the points that have the same gravitational potential by

490
00:25:40.079 --> 00:25:43.759
a contour, and you get a contoon map, and that

491
00:25:44.000 --> 00:25:47.559
is fundamentally the same as your ordinan survey map. Points

492
00:25:47.559 --> 00:25:51.599
that have the same gravitational potential will be metaphorically at

493
00:25:51.640 --> 00:25:54.240
the same altitude above sea level, same distance above sea

494
00:25:54.319 --> 00:25:57.200
level as a solar system. Now, if you draw a

495
00:25:57.240 --> 00:26:00.480
line directly between the Sun and the Earth, the Sun

496
00:26:00.519 --> 00:26:04.160
is at the bottom of an enormous blooming hole. You know,

497
00:26:04.200 --> 00:26:07.079
the contours are circular around it. The Earth is at

498
00:26:07.079 --> 00:26:09.599
the bottom of a smaller hole, and this is where

499
00:26:09.640 --> 00:26:12.559
the whole metaphor of weights on a rubber sheet bowing

500
00:26:12.599 --> 00:26:14.960
the rubber sheet comes from. So the Earth is at

501
00:26:15.000 --> 00:26:16.799
the bottom of its own hole that is smaller than

502
00:26:16.880 --> 00:26:19.359
the hole that the Sun makes. And so if you

503
00:26:19.400 --> 00:26:21.559
have a line between them, you effectively come up all

504
00:26:21.559 --> 00:26:24.200
from the Sun until you reach a certain point, and

505
00:26:24.240 --> 00:26:26.240
then you tip over and you sat falling down the earthshole.

506
00:26:26.319 --> 00:26:29.039
So you go downhill again. So between the two you've

507
00:26:29.039 --> 00:26:33.160
got like a saddle point where at the top of

508
00:26:33.160 --> 00:26:36.319
that saddle you're at a flat point where s basically

509
00:26:36.480 --> 00:26:39.440
gravitational potential is flat and you could balance, Say you

510
00:26:39.440 --> 00:26:41.200
could put a marble there and it would sit there.

511
00:26:41.519 --> 00:26:43.680
But if that marble goes slightly off in either direction,

512
00:26:43.759 --> 00:26:44.680
it'll roll down the hill.

513
00:26:44.680 --> 00:26:45.200
So if you get a.

514
00:26:45.200 --> 00:26:47.480
Little bit closer, then you'll fall off and roll towards

515
00:26:47.519 --> 00:26:49.440
the Sun. If you get a little bit closer to

516
00:26:49.519 --> 00:26:52.880
the Earth, you'll roll off and roll towards the Earth. Now,

517
00:26:53.000 --> 00:26:55.279
if you move out from two dimensions between the Earth

518
00:26:55.279 --> 00:26:58.920
and some three dimensions, if you roll clockwise or anti

519
00:26:59.000 --> 00:27:02.640
clockwise away from that saddle point, you'll actually be trying

520
00:27:02.640 --> 00:27:04.519
to roll uphill, so you'll fall back down into it.

521
00:27:04.960 --> 00:27:07.599
So you've got this kind of really is like a

522
00:27:07.599 --> 00:27:10.039
saddle point, where towards the Sun and towards the Earth

523
00:27:10.160 --> 00:27:12.680
you fall downhill, but at right angles to that you

524
00:27:12.759 --> 00:27:15.519
try and roll up hill. So you've got this local

525
00:27:16.119 --> 00:27:18.759
flat area where if you move a little bit ahead

526
00:27:18.839 --> 00:27:21.559
or behind it in your orbit, you'll roll back down.

527
00:27:21.920 --> 00:27:23.920
So you've got a bit of a restoring force there,

528
00:27:24.240 --> 00:27:26.160
but if you roll inward or outward.

529
00:27:25.759 --> 00:27:26.680
You'll fall off the hill.

530
00:27:27.519 --> 00:27:30.759
And that's why that lagrange point is an unstable one.

531
00:27:30.799 --> 00:27:34.359
It's like a saddle point. And the three lagrange points

532
00:27:34.400 --> 00:27:36.319
that are on the line between the Earth and the Sun,

533
00:27:37.000 --> 00:27:38.839
L one, which is between the Earth and the Sun,

534
00:27:39.079 --> 00:27:40.839
L two, which is on the far side of the

535
00:27:40.880 --> 00:27:44.759
Earth beyond the Earth but on that line, and L three,

536
00:27:44.759 --> 00:27:46.599
which is on the far side of the Sun opposite

537
00:27:46.680 --> 00:27:49.160
the Earth. Yeah, those points are all these kind of

538
00:27:49.160 --> 00:27:52.400
saddle points, so they're a bit more stable than normal

539
00:27:52.440 --> 00:27:54.880
space because you can imagine balancing on the flat part

540
00:27:54.920 --> 00:27:57.279
of the hill, but if you roll in either direction,

541
00:27:57.400 --> 00:28:01.240
you fall away. Now a lot of there are spacecraft

542
00:28:01.319 --> 00:28:03.640
sit at the inner or the outer lagrange point L

543
00:28:03.640 --> 00:28:06.160
one or L two. The ones at L one sit

544
00:28:06.200 --> 00:28:07.920
there because they can observe the Sun and give us

545
00:28:07.960 --> 00:28:10.759
prior warning if something's coming our way cell a mass ejection,

546
00:28:10.920 --> 00:28:13.839
something like that. The ones at L two sit there

547
00:28:13.880 --> 00:28:16.279
to be in a good position to observe space, but

548
00:28:16.440 --> 00:28:18.559
have station keeping with the Earth. They move around with

549
00:28:18.680 --> 00:28:21.480
the Earth, and that seems like the James Web Space telescope.

550
00:28:22.039 --> 00:28:24.880
But because those locations are these kind of saddle points,

551
00:28:24.920 --> 00:28:28.519
they're not perfectly stable. Those spacecraft have to have fuel

552
00:28:28.559 --> 00:28:30.759
to stay on stations, so if they start to drift downhill,

553
00:28:30.799 --> 00:28:33.359
they can push themselves back up and get back to

554
00:28:33.359 --> 00:28:35.960
the saddle point. And they actually do this by wabbling

555
00:28:35.960 --> 00:28:38.240
and librating around that point and have a little orbit.

556
00:28:38.799 --> 00:28:41.720
The other two lagrange points are L four and O five,

557
00:28:41.799 --> 00:28:43.920
or sixty degrees ahead and behind the Earth in its

558
00:28:44.000 --> 00:28:47.720
orbit around the Sun, and these are like enormous flat plateaus.

559
00:28:47.759 --> 00:28:51.319
If you look at a contour map of the gravitational

560
00:28:51.359 --> 00:28:53.599
potential of the cell system, you get these big kidney

561
00:28:53.640 --> 00:28:56.319
shaped areas that are pretty flat, and that means if

562
00:28:56.359 --> 00:28:59.279
you have your ball there, it could just sit there,

563
00:29:00.079 --> 00:29:01.640
even if you're quite a long way away from the

564
00:29:01.680 --> 00:29:04.279
center point of that lagrange point. You'd sit on one

565
00:29:04.319 --> 00:29:06.079
of these contours, and if you start to roll, you'd

566
00:29:06.079 --> 00:29:08.200
follow the contoe around, and you'd follow this kind of

567
00:29:08.559 --> 00:29:12.200
kidney shipped path, staying trapped around the lagrange point but

568
00:29:12.319 --> 00:29:16.440
vibrating around it. And they're like plateaus, so they're much

569
00:29:16.480 --> 00:29:19.720
more stable than the kind of saddle points, and that's

570
00:29:19.720 --> 00:29:22.599
why those are the points which in the outer Solar

571
00:29:22.640 --> 00:29:25.279
System have huge populations. In the orbit of Jupiter, have

572
00:29:25.359 --> 00:29:27.480
big populations in the orbit of Neptune. Those are the

573
00:29:27.519 --> 00:29:31.759
Juter and Neptune trojans. The other planets can have trojans too,

574
00:29:31.799 --> 00:29:34.759
but they tend to be temporary because the Solar System

575
00:29:34.839 --> 00:29:38.039
is not simply three objects, it's actually got all the planets.

576
00:29:38.079 --> 00:29:40.279
So if you're sadden near the lagrange points of Earth,

577
00:29:40.680 --> 00:29:43.799
you're getting gravitational pulls from Venus and Mars nearby, from

578
00:29:43.880 --> 00:29:46.440
Jupter and all the other planets as well, and eventually

579
00:29:46.440 --> 00:29:48.799
they'll pull you off the stable plateau and you'll fall away,

580
00:29:48.839 --> 00:29:51.680
so you'll only live there temporarily. Yea. But for Jupter

581
00:29:51.720 --> 00:29:54.720
and Neptune, those planets are so dominant compared to the

582
00:29:54.759 --> 00:29:56.799
other things around. They can hold things permanently at the

583
00:29:56.920 --> 00:30:00.680
least Lagrange points, and the motion of a objects at

584
00:30:00.720 --> 00:30:03.759
the alpha and l five points is that over hundreds

585
00:30:03.759 --> 00:30:06.599
of orbits, they we'll gradually librate around that alphour point,

586
00:30:06.640 --> 00:30:09.200
so they'll be on average sixty degrees our head or

587
00:30:09.200 --> 00:30:11.319
behind the planet, but they'll be moving around that and

588
00:30:11.319 --> 00:30:15.039
they'll be orbiting it. So the concept of trying to

589
00:30:15.119 --> 00:30:17.559
think about whether you can define a mass at the

590
00:30:17.559 --> 00:30:20.359
center of the la Grange point that holds them is

591
00:30:20.400 --> 00:30:24.759
not quite the physics that's going on. That librating around

592
00:30:24.759 --> 00:30:27.880
that point only works if you're in a frame of

593
00:30:27.920 --> 00:30:30.400
reference that is rotating with the orbit of the planet.

594
00:30:30.640 --> 00:30:33.640
So you're let's imagine we're looking at the Jupiter trojans.

595
00:30:33.680 --> 00:30:36.559
You imagine you somehow suspended above the plane of the

596
00:30:36.599 --> 00:30:39.440
Solar System, lying there, watching all the objects in the

597
00:30:39.440 --> 00:30:42.920
Solar System, and you're spinning once every twelve years, just

598
00:30:42.960 --> 00:30:45.559
as Jupiter orbits are some once every twelve years. So

599
00:30:45.640 --> 00:30:47.559
from your point of view, Jupiter and the Sun stain

600
00:30:47.680 --> 00:30:50.359
exactly the same place in your field of view. And

601
00:30:50.400 --> 00:30:53.000
then over much longer time scales of hundreds of years,

602
00:30:53.279 --> 00:30:57.079
these trojans would appay to orbit thet lagrange point. I

603
00:30:57.119 --> 00:30:59.480
guess you could if you wanted to try and construct

604
00:30:59.559 --> 00:31:03.079
some more to visualize that way. You imagine that there

605
00:31:03.119 --> 00:31:05.359
is a virtual mass at the Vela Grange points, and

606
00:31:05.400 --> 00:31:08.599
that's what the trogans are orbiting while they'll librate. It

607
00:31:08.640 --> 00:31:12.200
would have to be a spread out mass because if

608
00:31:12.240 --> 00:31:14.559
it was a point mass, they'd have much more circular orbits,

609
00:31:14.559 --> 00:31:16.720
they wouldn't have these kidney shaped things, so the Masso'd

610
00:31:16.799 --> 00:31:19.000
have to be spread out. But you could, I guess,

611
00:31:19.079 --> 00:31:22.680
visualize it and calculate it, but that would only be

612
00:31:22.759 --> 00:31:25.640
valid in the rotating reference frame, which is a bit

613
00:31:25.640 --> 00:31:29.599
of a conceit anyway. In the normal scheme of things,

614
00:31:29.599 --> 00:31:32.799
where everything's rotating around and you're not spinning above watching it,

615
00:31:33.400 --> 00:31:36.680
these objects are moving on orbitstead of very similar period

616
00:31:36.720 --> 00:31:39.839
to say Jupiter, but slightly longer, slightly shorter, and as

617
00:31:39.839 --> 00:31:42.680
they pull if it's a slightly short orbital period than Jupiter,

618
00:31:43.119 --> 00:31:45.359
gradually they'll insure head of Jupe to get further and

619
00:31:45.440 --> 00:31:49.480
further ahead. Eventually they drift outwards and they're now further

620
00:31:49.519 --> 00:31:51.039
from the Sun, so they're now going around the Sun

621
00:31:51.119 --> 00:31:54.039
slower than Jupiter. And they sat fall back towards it

622
00:31:54.400 --> 00:31:56.759
until Jupiter's gravity tweaks them and they fall inwards a

623
00:31:56.759 --> 00:31:59.480
better than they start moving quicker. So it's actually all

624
00:31:59.519 --> 00:32:01.440
down to the traction between Ju to the Sun and

625
00:32:01.519 --> 00:32:05.039
the object in that case, rather than a virtual mass

626
00:32:05.039 --> 00:32:07.240
off there. So I can see what you're thinking about,

627
00:32:07.279 --> 00:32:09.720
and I can see it as being something that is

628
00:32:09.759 --> 00:32:13.279
a good model to help you visualize what's going on,

629
00:32:13.960 --> 00:32:16.559
But it's not the kind of thing we do calculations of,

630
00:32:17.039 --> 00:32:20.880
and I don't think it's a sufficiently advanced mental model

631
00:32:20.880 --> 00:32:22.839
that you'd want to get to that level with because

632
00:32:22.880 --> 00:32:26.319
it starts taking down a rabbit hole of the physics

633
00:32:26.359 --> 00:32:28.480
doesn't actually work that way, and you can put yourself

634
00:32:28.519 --> 00:32:31.079
in traps when you do that. But it is a

635
00:32:31.119 --> 00:32:34.960
really nice way to visualize initially how it works. It's

636
00:32:35.160 --> 00:32:38.440
if you're librating around one of the lagrange points, it

637
00:32:38.480 --> 00:32:40.799
is as though there is a force keeping you trug

638
00:32:40.839 --> 00:32:42.720
to it. So it's as though there is a mass there,

639
00:32:43.440 --> 00:32:46.960
keeping attracting you towards the lagrange point. It's just that

640
00:32:46.960 --> 00:32:49.000
that isn't actually a mass there. It's simpler to do

641
00:32:49.079 --> 00:32:51.480
with the intraction of all the other objects floating around

642
00:32:52.000 --> 00:32:55.480
that create that virtual thing that keeps you locked around

643
00:32:55.480 --> 00:32:55.960
that place.

644
00:32:56.440 --> 00:33:00.000
M hm okay ho'pefully then helped you out, Man.

645
00:33:02.720 --> 00:33:05.440
Broad piece MutS.

646
00:33:05.960 --> 00:33:09.279
And our next question and our final question kind of

647
00:33:09.319 --> 00:33:13.319
relates to this question that Mark raised, And this came

648
00:33:13.319 --> 00:33:16.079
from a YouTuber. I don't know their name, but that's okay.

649
00:33:17.279 --> 00:33:22.119
Can you do a deep dive on the Cordleski plasma

650
00:33:22.160 --> 00:33:25.440
clouds or do we not have much information on these

651
00:33:25.559 --> 00:33:29.359
strange things now I look them up. The Cordleski or

652
00:33:29.559 --> 00:33:34.279
Cordleuski clouds are two large, tenuous dust clouds located at

653
00:33:34.559 --> 00:33:38.119
L four and L five lagrange points of the Earth

654
00:33:38.160 --> 00:33:41.319
Moon system. Originally predicted in the nineteen fifties, first spotted

655
00:33:41.319 --> 00:33:45.079
in the sixties, their existence was long doubted, but recently

656
00:33:45.119 --> 00:33:49.400
confirmed in twenty eighteen by observations using a polarizing filter

657
00:33:49.480 --> 00:33:53.200
that detected reflected sunlight from the dust. While they are

658
00:33:53.400 --> 00:33:57.000
called dust clouds, summary research suggests they are a complex

659
00:33:57.440 --> 00:34:01.039
a complex form of dusty PLASMI ah, yes.

660
00:34:01.640 --> 00:34:07.240
So this is a fascinating question. The Koondleshki clouds are transient,

661
00:34:07.480 --> 00:34:09.440
and I think that's probably part of why they've been

662
00:34:09.480 --> 00:34:14.400
hard to confirm because there are areas where as we

663
00:34:14.599 --> 00:34:17.159
just described those lagrange points. If you only have the

664
00:34:17.199 --> 00:34:20.519
Earth and the Moon in space and nothing else, then

665
00:34:20.519 --> 00:34:22.880
the leading alpha and OL five lagrange points of the

666
00:34:22.880 --> 00:34:25.960
Moon could be stable on million year, billionaire time scales.

667
00:34:26.440 --> 00:34:29.360
But in actuality in the system where you've got the Sun,

668
00:34:29.400 --> 00:34:32.719
you've got all the other planets, and for small objects,

669
00:34:33.320 --> 00:34:36.079
the influence of the solar wind and the Sun's radiation

670
00:34:36.199 --> 00:34:39.440
becomes significant as well. What that means is that it

671
00:34:39.480 --> 00:34:43.719
becomes easier to escape from those lagrange points. By being

672
00:34:43.719 --> 00:34:45.880
easier to escape, it also means it's easy to get

673
00:34:45.880 --> 00:34:48.840
trapped there in the first place. Of course, if you

674
00:34:48.880 --> 00:34:51.599
can get out, you can get it. And so what

675
00:34:51.639 --> 00:34:54.400
that means is you can imagine as the Moon and

676
00:34:54.440 --> 00:34:56.280
the Earth are all but in the common center of mass,

677
00:34:56.679 --> 00:34:59.039
sixty degrees ahead and behind of the Moon are these

678
00:34:59.079 --> 00:35:02.599
areas are space in the Moon's orbit that are like

679
00:35:02.679 --> 00:35:05.400
little dimples in space where it's easy for stuff to

680
00:35:05.440 --> 00:35:08.480
build up and get captured there temporarily before getting cleaned

681
00:35:08.519 --> 00:35:11.440
out again. They're not deep enough for things to get

682
00:35:11.480 --> 00:35:16.159
hooked there permanently. But what that means is interplanetary dust,

683
00:35:16.760 --> 00:35:18.800
bits of the solar wind that aren't moving that quick

684
00:35:19.960 --> 00:35:23.639
stuff splutted off the Moon by impact events, can some

685
00:35:23.719 --> 00:35:25.880
of that can congregate there and spend a certain amount

686
00:35:25.920 --> 00:35:27.880
of time there. Now, the dynamics of it as such

687
00:35:27.880 --> 00:35:29.639
as been a lot of modeling done of this that

688
00:35:30.639 --> 00:35:33.079
if dust is there for a reasonable amount of time,

689
00:35:33.119 --> 00:35:35.840
it will actually get congregated into kind of bar features

690
00:35:35.840 --> 00:35:37.960
and streams. I think you'll have to get a bit

691
00:35:37.960 --> 00:35:40.599
of structure in it before it gets cleaned out. But

692
00:35:40.679 --> 00:35:43.039
fundamentally what's going to be happening is that you've got

693
00:35:43.159 --> 00:35:47.559
dust and gas getting temporarily captured there and then getting

694
00:35:47.559 --> 00:35:50.239
cleaned out again, and so the amount of material there

695
00:35:50.280 --> 00:35:53.280
will depend on what's happening at the time. These were

696
00:35:53.320 --> 00:35:55.840
proposed a good long time ago, and they were first

697
00:35:55.960 --> 00:35:58.800
kind of reported to be observed in nineteen sixty one

698
00:35:58.920 --> 00:36:03.639
by Kordolowski. That's why they take that person's name and

699
00:36:04.760 --> 00:36:07.559
got photos observe them with the naked eye. There are

700
00:36:07.559 --> 00:36:11.079
about two magnitudes at that time fainter than the Gaganshine,

701
00:36:11.079 --> 00:36:15.039
which is dust opposite the Moon in its orbit and

702
00:36:15.280 --> 00:36:18.880
is visible as a very faint, fuzzy blob. So they're

703
00:36:18.960 --> 00:36:21.000
very hard to pick up very hard spot. And for

704
00:36:21.039 --> 00:36:22.960
many years after that other people looked for them and

705
00:36:23.000 --> 00:36:25.079
could not see them, and that's where the controversy came

706
00:36:25.119 --> 00:36:28.920
about that they're probably not there. The much more recent

707
00:36:28.920 --> 00:36:32.239
observations by Hungarian astronomers made use of polar eimitary to

708
00:36:32.280 --> 00:36:35.159
actually make these things easier to see, and they were

709
00:36:35.239 --> 00:36:39.119
able to see them. Now there is I would have

710
00:36:39.159 --> 00:36:42.079
thought some debate over whether these have been there permanently

711
00:36:42.119 --> 00:36:44.000
since then, or whether what's happening is that the times

712
00:36:44.039 --> 00:36:47.000
have been detected at times when the dust and gas

713
00:36:47.079 --> 00:36:49.119
there has been a bit denser than normal, making them

714
00:36:49.119 --> 00:36:51.360
easier to see. Yeah, because if this is a time

715
00:36:51.440 --> 00:36:54.440
varying population of stuff there, there will be times when

716
00:36:54.440 --> 00:36:57.800
you see more, times when you see less. And again,

717
00:36:58.000 --> 00:37:00.639
PhD student and again it's just sick her over in

718
00:37:00.679 --> 00:37:05.400
the US. She's talking with Aaron Bully possibly looking at

719
00:37:05.400 --> 00:37:08.119
and doing some modeling of dust ejection from the Moon

720
00:37:09.159 --> 00:37:10.599
and where it would end up, and some of that

721
00:37:10.679 --> 00:37:13.480
dust would temporarily end up in the La Grande points,

722
00:37:13.519 --> 00:37:16.119
become part of the cordialscia clouds, and then disperse again.

723
00:37:16.880 --> 00:37:19.960
So the evidences that they're there, the evidences that they're transient.

724
00:37:20.519 --> 00:37:22.519
The idea that there could be plasma there as well

725
00:37:22.639 --> 00:37:24.719
is just better around the same physics of it being

726
00:37:24.880 --> 00:37:28.440
an area which is like a little dimple where things

727
00:37:28.440 --> 00:37:30.320
can build up and be held there for a little while.

728
00:37:30.360 --> 00:37:33.440
And we're aware that when you've got a perfectly smooth floor,

729
00:37:33.599 --> 00:37:35.559
the dust stays spread evenly, but if you've got any

730
00:37:35.559 --> 00:37:37.719
little dimples and stuff like that, dust can build up

731
00:37:37.719 --> 00:37:39.679
there until the gust of wind blows it out. It's

732
00:37:39.719 --> 00:37:43.280
effectively what's going on there. So they're really interesting. It's

733
00:37:43.360 --> 00:37:47.280
quite likely that all the other objects in the Solar

734
00:37:47.320 --> 00:37:49.920
System would have things like this as well, So Mars's

735
00:37:49.960 --> 00:37:52.920
Moon's Phobos and Demos. They're much less massive than our moon,

736
00:37:52.960 --> 00:37:54.960
so the lagrange points won't be much tinier, but you

737
00:37:55.039 --> 00:37:58.000
might get similar things there. We know that among the

738
00:37:58.039 --> 00:38:00.480
boons of Second we've got a couple of co orbitals satellites,

739
00:38:00.480 --> 00:38:03.719
including a couple of satellites that actually have Trojan companions.

740
00:38:04.280 --> 00:38:07.000
It's not just Jupter and Neptune that have permanent trojans.

741
00:38:07.480 --> 00:38:10.280
It's not just Earth and Mars, Saturn and Euros that

742
00:38:10.360 --> 00:38:14.239
have temporary trojans. There are actually Trojan satellites in the

743
00:38:14.280 --> 00:38:18.119
Saturnian system. And this is just one aspect of this now.

744
00:38:18.920 --> 00:38:21.039
You know, you could imagine that in a very very

745
00:38:21.079 --> 00:38:22.960
different world we could have had the moon and then

746
00:38:22.960 --> 00:38:24.800
we could have had a couple of small satellites, one

747
00:38:24.880 --> 00:38:27.639
leading it, one trailing. It's a bit and it's quite

748
00:38:27.679 --> 00:38:30.800
possible that after the moon forming impact there may well

749
00:38:30.840 --> 00:38:34.000
have been temporary kind of agglomerations of matter there on

750
00:38:34.000 --> 00:38:36.440
a much more substantial level as the Moon was forming.

751
00:38:36.800 --> 00:38:40.559
You can even have you know, small objects been accumulating

752
00:38:40.559 --> 00:38:42.480
their forming there and then escaping and all the.

753
00:38:42.400 --> 00:38:42.920
Rest of it.

754
00:38:43.400 --> 00:38:47.079
But hopefully that covers stuff. It is a really fascinating topic.

755
00:38:47.760 --> 00:38:47.960
You know.

756
00:38:48.039 --> 00:38:49.960
The kind of imagery people have done to figure this

757
00:38:50.000 --> 00:38:53.599
out back then was really challenging. You're talking about using

758
00:38:53.639 --> 00:38:57.679
a very fast, wide angled lens and doing menthy exposures

759
00:38:57.719 --> 00:38:59.840
to try and get a little bit of contrast between

760
00:38:59.840 --> 00:39:02.239
the rightness of the sky where the clouds are and

761
00:39:02.280 --> 00:39:03.440
the brightness of the sky.

762
00:39:03.239 --> 00:39:04.079
Where they aren't.

763
00:39:04.320 --> 00:39:06.679
The more recent work by the Hungarian team in twenty

764
00:39:06.719 --> 00:39:09.800
eighteen did some very very clever stuff where then it

765
00:39:09.920 --> 00:39:13.320
only imaged the clouds at the L five point when

766
00:39:13.360 --> 00:39:15.280
they were there, and did the polarimetry, but they also

767
00:39:15.320 --> 00:39:18.239
imaged the same part of the sky when the L

768
00:39:18.320 --> 00:39:22.039
five point wasn't there. They also imaged it when there

769
00:39:22.039 --> 00:39:25.599
were some high clouds like Cyrus there, when aircraft contrails

770
00:39:25.599 --> 00:39:28.280
were passing through that area of the sky and things

771
00:39:28.320 --> 00:39:30.679
like that, in order to have comparisons from other objects

772
00:39:30.679 --> 00:39:32.960
that had in the past been suggested as giving false

773
00:39:33.000 --> 00:39:36.320
positives here, and they were able to confirm that actually, no,

774
00:39:36.400 --> 00:39:38.079
it was the presence of the L five point and

775
00:39:38.199 --> 00:39:40.639
the dust there was what they got because it looked

776
00:39:40.679 --> 00:39:44.400
sufficiently different to the other things that it was robust,

777
00:39:44.840 --> 00:39:46.800
which is very very cool, And it's a good example

778
00:39:46.840 --> 00:39:49.559
of when you're trying to find something that's incredibly hard

779
00:39:49.559 --> 00:39:52.960
to see and hard to study, then you need to

780
00:39:53.000 --> 00:39:56.400
do some really very impressive and very innovative observations to.

781
00:39:56.360 --> 00:39:57.039
Make that work.

782
00:39:57.599 --> 00:39:59.559
And you know, people have done some lovely modeling of

783
00:39:59.639 --> 00:40:02.320
orbital connects to see how long things would reside there,

784
00:40:02.840 --> 00:40:05.400
and there've even been proposals of sending spacecraft there to

785
00:40:05.480 --> 00:40:08.320
check it out. But that's about where we sit with

786
00:40:08.360 --> 00:40:10.440
them at the minute, and it is a fascinating subject.

787
00:40:10.440 --> 00:40:15.079
We'll learn more in the years to come. Doubtless. When

788
00:40:15.159 --> 00:40:17.239
Jessica's PhD is finished and she gets to go on

789
00:40:17.280 --> 00:40:19.920
and do this further research, we'll learn a little bit

790
00:40:19.960 --> 00:40:21.840
more about dust that is kicked off the surface of

791
00:40:21.880 --> 00:40:24.480
the moon and where it goes and how that contributes.

792
00:40:25.079 --> 00:40:27.320
But like everything, you know, there's more to learn than

793
00:40:27.360 --> 00:40:29.159
we already have done, and we're still at the start

794
00:40:29.159 --> 00:40:30.360
of this journey realistically.

795
00:40:30.440 --> 00:40:33.679
Yeah, yeah, absolutely, Yeah, great question and great to get

796
00:40:34.159 --> 00:40:37.519
a question from our YouTube audience, which is ever growing.

797
00:40:37.599 --> 00:40:38.599
So thank you for.

798
00:40:38.559 --> 00:40:43.800
That, and we are done. Thanks for answering all those questions, Johnny.

799
00:40:43.920 --> 00:40:44.559
That's a pleasure.

800
00:40:44.599 --> 00:40:46.760
It's good to get some kind of brand teasers and

801
00:40:46.760 --> 00:40:48.280
stuff that makes your head hurt a little bit.

802
00:40:48.280 --> 00:40:49.239
That does, doesn't it.

803
00:40:49.519 --> 00:40:54.320
Yeah, Yeah, I think we're Fred and I and now

804
00:40:54.320 --> 00:40:59.760
yourself are constantly amazed by the depth of the inquisitiveness

805
00:40:59.760 --> 00:41:00.559
of it audience.

806
00:41:00.639 --> 00:41:00.880
Yeah.

807
00:41:00.960 --> 00:41:02.400
I think that's a good way of just growing it.

808
00:41:02.440 --> 00:41:05.280
But all right, if you have questions for us, and

809
00:41:05.320 --> 00:41:08.320
we could sure use some audio questions, we are thin

810
00:41:08.440 --> 00:41:11.679
on the ground, jump on our website and send them in.

811
00:41:12.199 --> 00:41:15.639
It's space Nuts podcast dot com or space Nuts dot Io.

812
00:41:15.639 --> 00:41:17.440
Click on the AMA link at the top and you

813
00:41:17.440 --> 00:41:20.119
can send text and audio questions to us that way

814
00:41:20.599 --> 00:41:23.199
if you so desire, and don't forget to tell us

815
00:41:23.239 --> 00:41:27.719
who you are or where you're from, or both. Thanks Johnny,

816
00:41:27.760 --> 00:41:28.679
we'll catch you real soon.

817
00:41:29.840 --> 00:41:31.599
Thanks for having me, Always a pleasure.

818
00:41:31.679 --> 00:41:34.440
John ty Horner, Professor of Astrophysics at the University of

819
00:41:34.480 --> 00:41:38.599
Southern Queensland here in the studio, couldn't be with us

820
00:41:38.639 --> 00:41:40.920
again today. You got himself stuck another Grange point and

821
00:41:41.039 --> 00:41:43.880
from me Andrew Dunkley, Thanks for your company. See you

822
00:41:44.000 --> 00:41:48.079
on the next episode of Space Nuts. Bye bye, You'll

823
00:41:48.159 --> 00:41:49.840
be to the Space.

824
00:41:49.599 --> 00:41:56.800
Nuts podcast available at Apple Podcasts, Spotify, iHeartRadio, or your

825
00:41:56.880 --> 00:41:58.239
favorite podcast player.

826
00:41:58.400 --> 00:41:59.719
You can also stream.

827
00:41:59.440 --> 00:42:01.559
Onto Mare at fights dot com.

828
00:42:01.719 --> 00:42:06.960
This has been another quality podcast production from fights dot Com.