Cosmic Queries: Space Emptiness, Tidally Locked Worlds & Sonic Orbits

WEBVTT

0
00:00:00.000 --> 00:00:02.800
Andrew Dunkley: Hello again. Thanks for joining us on Space Nuts. My

1
00:00:02.800 --> 00:00:05.800
name is Andrew Dunkley, your host, and this is a Q and

2
00:00:05.800 --> 00:00:08.400
A edition. And questions today coming

3
00:00:08.560 --> 00:00:11.360
from Kevin about, uh, the emptiness

4
00:00:11.440 --> 00:00:14.280
of space. Uh, Casey wants to talk about

5
00:00:14.280 --> 00:00:17.040
tidally locked planets. Hazel is

6
00:00:17.040 --> 00:00:19.880
asking about sonification. We've talked about that in

7
00:00:19.880 --> 00:00:21.760
the past. And Rusty.

8
00:00:22.520 --> 00:00:25.420
Uh, Rusty. Gee, it's good to be back. Uh,

9
00:00:25.420 --> 00:00:28.360
I really missed you, Rusty. And your questions about bulk

10
00:00:28.360 --> 00:00:30.990
motions in the Universe can't wait.

11
00:00:31.070 --> 00:00:33.550
Voice Over Guy: 15 seconds. Guidance is internal.

12
00:00:33.790 --> 00:00:36.510
10, 9. Ignition

13
00:00:36.510 --> 00:00:39.474
sequence start. Space nuts. 5, 4, 3,

14
00:00:39.546 --> 00:00:42.354
2. 1, 2, 3, 4, 5, 5, 4,

15
00:00:42.426 --> 00:00:45.350
3, 2, 1. Space nuts. Astronauts

16
00:00:45.350 --> 00:00:46.590
report it feels good.

17
00:00:47.150 --> 00:00:50.110
Andrew Dunkley: Joining us once again is his good self, Professor Fred Watson.

18
00:00:50.110 --> 00:00:52.430
What's that? Astronomer at large. Hello, Fred Watson.

19
00:00:53.150 --> 00:00:55.950
Professor Fred Watson: Hello, Andrew. Good to be back. And good to see your

20
00:00:55.950 --> 00:00:56.830
smiling face again.

21
00:00:57.760 --> 00:01:00.680
Andrew Dunkley: Yes, I've got a smiling face. I'm nearly over the jet lag.

22
00:01:00.680 --> 00:01:03.600
You don't smile much when you got jet lag. That

23
00:01:03.600 --> 00:01:04.560
stuff's horrible.

24
00:01:04.720 --> 00:01:05.200
Professor Fred Watson: Yeah.

25
00:01:05.520 --> 00:01:08.240
Andrew Dunkley: Um, there should be a pill for that. There really should.

26
00:01:08.640 --> 00:01:11.560
Don't know why someone hasn't invented one yet. Maybe I

27
00:01:11.560 --> 00:01:14.400
should. I'd make billions, I would.

28
00:01:14.880 --> 00:01:15.680
Professor Fred Watson: Here, take this.

29
00:01:15.680 --> 00:01:18.640
Andrew Dunkley: No jet lag. Done and dusted. How you been,

30
00:01:18.640 --> 00:01:19.040
Fred Watson?

31
00:01:19.860 --> 00:01:22.720
Professor Fred Watson: Uh, very well, thanks. I don't have jet lag. Um, and

32
00:01:22.720 --> 00:01:25.640
that's good. Um, I guess the nearest to a jet lag

33
00:01:25.640 --> 00:01:28.520
pill is melatonin. Um, some of my colleagues

34
00:01:28.520 --> 00:01:31.460
who travel a lot used to insist

35
00:01:31.460 --> 00:01:34.380
on melatonin tablets. I've never used them because

36
00:01:34.380 --> 00:01:37.260
I always managed to sleep. All right. But you're right, jet lag

37
00:01:37.340 --> 00:01:38.540
can be a bit fearsome.

38
00:01:39.180 --> 00:01:42.060
Andrew Dunkley: Yeah. And you don't want to get the melatonin tablets

39
00:01:42.060 --> 00:01:44.660
mixed up with the melanoma tablets, because that can be

40
00:01:44.660 --> 00:01:45.100
lethal.

41
00:01:45.900 --> 00:01:47.540
Professor Fred Watson: That's right. That could be, uh.

42
00:01:47.660 --> 00:01:50.060
Andrew Dunkley: That's a terrible joke. See, I'm back. I'm back.

43
00:01:51.420 --> 00:01:54.220
Dreadful jokes. Um, we

44
00:01:54.380 --> 00:01:57.220
might as well get straight into it and see if we can solve some of

45
00:01:57.220 --> 00:02:00.210
these riddles that people have sent to us. Our

46
00:02:00.210 --> 00:02:03.090
first question comes from Kevin. Uh, Kevin

47
00:02:03.090 --> 00:02:06.050
is a patron and gives, uh, me an opportunity to thank all

48
00:02:06.050 --> 00:02:08.930
our patrons for pitching, uh, into the show. We really

49
00:02:08.930 --> 00:02:11.530
do appreciate that, and we think you are

50
00:02:11.530 --> 00:02:14.410
terrific. And if anyone wants

51
00:02:14.410 --> 00:02:17.130
to, uh, look into that, they can do that via our website,

52
00:02:17.420 --> 00:02:20.370
um, Patreon, uh,.comspacenuts, I think, is

53
00:02:20.370 --> 00:02:21.290
also where you can go.

54
00:02:21.610 --> 00:02:24.170
So Kevin's question. How

55
00:02:24.170 --> 00:02:27.090
empty is space? Or to ask

56
00:02:27.090 --> 00:02:29.370
another way, how is a

57
00:02:29.370 --> 00:02:31.490
spacecraft like New Horizons?

58
00:02:32.020 --> 00:02:32.140
Professor Fred Watson: Ah.

59
00:02:32.290 --> 00:02:35.170
Andrew Dunkley: How is it that it can travel millions of miles

60
00:02:35.170 --> 00:02:38.010
through space and risk, um, hitting a

61
00:02:38.010 --> 00:02:40.850
Grain of matter that I assume would destroy it.

62
00:02:41.720 --> 00:02:44.490
Um, and that's a really good question because I've

63
00:02:44.490 --> 00:02:47.450
often wondered the same thing. How do we go through

64
00:02:47.450 --> 00:02:50.050
space, uh, and not get

65
00:02:50.210 --> 00:02:52.640
hammered by something and. Yeah,

66
00:02:52.640 --> 00:02:53.440
oblivion.

67
00:02:54.980 --> 00:02:57.720
Professor Fred Watson: Um, yeah, it is a great question. Uh, it's

68
00:02:57.720 --> 00:03:00.240
got um, a uh, very

69
00:03:00.240 --> 00:03:03.120
characteristic two word, uh answer, Andrew, which

70
00:03:03.120 --> 00:03:05.440
is. That's a wonder. No,

71
00:03:06.720 --> 00:03:08.639
no, b. Of course, yeah, you're right.

72
00:03:10.680 --> 00:03:13.040
Uh, how empty is space? It

73
00:03:13.040 --> 00:03:16.040
depends. Uh, and it depends, it

74
00:03:16.040 --> 00:03:18.960
depends which bit of space you're in. Um, and

75
00:03:19.520 --> 00:03:22.320
so, uh, yeah, I think Kevin's right.

76
00:03:24.000 --> 00:03:27.000
Um, thinking about the James Webb Space Telescope which

77
00:03:27.000 --> 00:03:29.800
indeed did travel, uh, well,

78
00:03:29.800 --> 00:03:32.680
it's 1.5 million kilometres. So it's about a million

79
00:03:32.680 --> 00:03:35.200
miles. That was the distance that it travelled from

80
00:03:35.680 --> 00:03:38.240
Earth uh, to its uh, location,

81
00:03:39.200 --> 00:03:42.160
uh, because it settled in a uh, region

82
00:03:42.160 --> 00:03:44.400
called the Lagrange second Lagrange point

83
00:03:44.720 --> 00:03:47.690
L2 where the stable gravitational

84
00:03:47.690 --> 00:03:50.490
pull. But uh, one of the

85
00:03:50.490 --> 00:03:53.250
other things about the Lagrange points is because they're

86
00:03:53.250 --> 00:03:56.220
stable they attract dust. Um,

87
00:03:56.220 --> 00:03:59.050
and so they're relatively dusty regions of space.

88
00:03:59.660 --> 00:04:02.250
Um, and actually within just a few months

89
00:04:02.570 --> 00:04:05.410
of um, uh, of the deployment

90
00:04:05.410 --> 00:04:07.930
of the jwst, there was

91
00:04:08.170 --> 00:04:11.170
a micrometeorite, um, impact. This would

92
00:04:11.170 --> 00:04:13.910
be something the size of grain of dust,

93
00:04:13.910 --> 00:04:16.630
maybe even smaller, hitting at maybe 30

94
00:04:16.630 --> 00:04:19.350
kilometres per second. That left a permanent

95
00:04:19.510 --> 00:04:21.350
dent in one of the mirror segments

96
00:04:22.150 --> 00:04:24.950
today. Yes, um, they've been

97
00:04:24.950 --> 00:04:27.910
quite lucky actually because I thought, you know, that was within a

98
00:04:27.910 --> 00:04:30.750
couple of months of deployment. I was thinking my

99
00:04:30.750 --> 00:04:33.710
God, if that's the case, we're going to have no mirror at all within a

100
00:04:33.710 --> 00:04:36.230
year. But in fact I think it's been

101
00:04:36.470 --> 00:04:39.280
relatively unscathed uh, uh,

102
00:04:39.360 --> 00:04:42.240
for the rest of its career. It's doing a fabulous job. We often talk

103
00:04:42.240 --> 00:04:44.320
about oh isn't JWST

104
00:04:44.720 --> 00:04:47.600
observations uh, here on spacenuts.

105
00:04:48.320 --> 00:04:51.160
So um, basically what I'm saying is that the Earth's

106
00:04:51.160 --> 00:04:54.120
environment in particular is quite dusty and that's

107
00:04:54.120 --> 00:04:57.120
because it's near the inner part of the solar system. There's a lot

108
00:04:57.120 --> 00:04:59.960
of comets come from the outer edges of the solar

109
00:04:59.960 --> 00:05:02.400
system which shed dust as they get near the sun.

110
00:05:02.800 --> 00:05:05.680
The dust is released from its IC matrix

111
00:05:05.920 --> 00:05:08.550
and uh, and so comet trails are dusty,

112
00:05:08.840 --> 00:05:11.350
uh, and that uh, adds to the

113
00:05:11.680 --> 00:05:14.510
uh, general dust that is the remnant of the

114
00:05:14.510 --> 00:05:17.350
origins of the solar system. The plane of the Earth's

115
00:05:17.350 --> 00:05:20.310
orbit is quite dusty. And so yes, something like

116
00:05:20.630 --> 00:05:23.330
the web is going to be always at risk uh,

117
00:05:23.430 --> 00:05:26.350
from uh, being hit by rain of

118
00:05:26.350 --> 00:05:29.270
material. But if you go out um, into

119
00:05:29.270 --> 00:05:31.830
the outer part of the solar system,

120
00:05:32.500 --> 00:05:35.290
uh, beyond the orbit of Neptune. You get a much clearer view

121
00:05:35.290 --> 00:05:38.290
because there's virtually no dust out there. Uh, and

122
00:05:38.290 --> 00:05:40.890
that's one reason why the New Horizons

123
00:05:41.130 --> 00:05:43.690
spacecraft measured, uh, the

124
00:05:43.690 --> 00:05:46.410
sky background there as being fainter

125
00:05:46.490 --> 00:05:49.130
than we have in the inner solar system, because there's no

126
00:05:49.290 --> 00:05:52.210
dust reflecting sunlight. Um, and

127
00:05:52.210 --> 00:05:55.210
that's an interesting experiment. It actually caused a bit of a revision of

128
00:05:55.210 --> 00:05:58.090
the number of galaxies that we think the universe has.

129
00:05:58.610 --> 00:06:01.470
Um, I'm not going to go in that direction now because it's

130
00:06:01.470 --> 00:06:04.270
another can of worms. But, uh, what that's saying

131
00:06:04.270 --> 00:06:07.190
is that, uh, in terms of dust, uh, once you

132
00:06:07.190 --> 00:06:10.150
get beyond the inner solar system, then it's fairly

133
00:06:10.150 --> 00:06:12.910
dust free. Of course, there's other

134
00:06:12.910 --> 00:06:15.390
stuff, uh, floating around in space.

135
00:06:15.710 --> 00:06:18.310
Lots of subatomic particles. There's the wind of

136
00:06:18.310 --> 00:06:21.270
subatomic particles that come from the sun. They can have an

137
00:06:21.270 --> 00:06:23.950
effect, not putting a dent in your mirror, but

138
00:06:23.950 --> 00:06:26.590
certainly can damage, uh, electronics and things of that

139
00:06:26.590 --> 00:06:29.390
sort at the atomic level. Uh, and

140
00:06:29.550 --> 00:06:32.490
once again, that's, um, more true nearer to

141
00:06:32.490 --> 00:06:35.330
the sun than further out. So when you get to interstellar

142
00:06:35.330 --> 00:06:38.250
space, uh, the average density is pretty low,

143
00:06:38.570 --> 00:06:41.410
Although interstellar space is populated by giant

144
00:06:41.410 --> 00:06:44.370
clouds of gas and dust. Uh, and so if you get in one of

145
00:06:44.370 --> 00:06:47.170
those, suddenly you've got, um, material around you

146
00:06:47.170 --> 00:06:50.050
again. It's still very, very rarefied. It's still better than

147
00:06:50.050 --> 00:06:53.010
the highest vacuum we can create artificially on

148
00:06:53.010 --> 00:06:55.610
Earth. But, um, it's not empty

149
00:06:55.610 --> 00:06:58.330
completely. Uh, one of the things, though, that

150
00:06:58.330 --> 00:07:00.970
illuminates to me just how empty space is,

151
00:07:01.210 --> 00:07:03.970
is the fact that we can look through

152
00:07:03.970 --> 00:07:06.840
space, uh, to a time, uh,

153
00:07:06.840 --> 00:07:09.770
13.8 billion years ago,

154
00:07:10.280 --> 00:07:13.250
uh, when the universe was still glowing brightly. We can still see

155
00:07:13.250 --> 00:07:16.090
the flash of the Big Bang. And that's because the photons that

156
00:07:16.090 --> 00:07:19.010
were emitted 13.8 billion years

157
00:07:19.010 --> 00:07:21.890
ago are still going strong. Uh, we see

158
00:07:21.890 --> 00:07:24.890
them now as microwaves, uh, because the universe,

159
00:07:25.050 --> 00:07:27.450
the expansion of the universe, has stretched them their

160
00:07:27.450 --> 00:07:30.390
waveleng. Uh, but that tells you how empty space is.

161
00:07:30.390 --> 00:07:33.030
The fact that we can see distant galaxies out to almost

162
00:07:33.030 --> 00:07:35.910
the origin of galaxies, and

163
00:07:35.910 --> 00:07:38.510
then beyond that, we can see the cosmic

164
00:07:38.510 --> 00:07:41.270
microwave background radiation. Uh, you'd think

165
00:07:41.270 --> 00:07:44.110
there will be something in the universe that will make it a bit more opaque

166
00:07:44.110 --> 00:07:47.030
than it is, but it is incredibly transparent, which

167
00:07:47.030 --> 00:07:49.030
tells you that it's pretty damned empty.

168
00:07:49.910 --> 00:07:52.870
Andrew Dunkley: You were also like, I haven't. It's been three months and I

169
00:07:52.870 --> 00:07:55.790
haven't been able to insult Huw once. So, um, you know,

170
00:07:55.790 --> 00:07:58.600
what you just said also applies to Huw Um,

171
00:07:59.030 --> 00:08:01.750
you know, empty, big void, nothing.

172
00:08:04.790 --> 00:08:06.390
Professor Fred Watson: Don't know why you're. No reaction.

173
00:08:06.630 --> 00:08:07.990
Andrew Dunkley: No reaction from you.

174
00:08:09.350 --> 00:08:12.310
So diplomatic. Sorry, Huw, couldn't

175
00:08:12.310 --> 00:08:15.030
help it. Golden opportunity. But

176
00:08:15.030 --> 00:08:17.910
yeah, in answer to Kevin's question, though, it's pretty

177
00:08:17.910 --> 00:08:20.790
sparse. Like, you know, you'd have to be very

178
00:08:20.790 --> 00:08:23.750
unlucky to take your 30 gazillion dollar

179
00:08:24.070 --> 00:08:26.310
Ferrari spaceship out there and

180
00:08:26.830 --> 00:08:29.590
suddenly realise that it's been destroyed by a

181
00:08:29.590 --> 00:08:31.870
spec dust. You have to be,

182
00:08:32.510 --> 00:08:35.070
you know, really unlucky.

183
00:08:35.310 --> 00:08:37.910
Well, hang on, maybe a Tesla

184
00:08:37.910 --> 00:08:38.590
Roadster.

185
00:08:38.910 --> 00:08:39.310
Professor Fred Watson: Yeah.

186
00:08:39.310 --> 00:08:41.630
Andrew Dunkley: Or something like that. You never know.

187
00:08:42.030 --> 00:08:42.590
Professor Fred Watson: That's right.

188
00:08:42.650 --> 00:08:45.430
Andrew Dunkley: Um, thank you Kevin, and thank you for your ongoing

189
00:08:45.430 --> 00:08:48.270
support as a patron of space nuts. We

190
00:08:48.270 --> 00:08:50.510
appreciate it. Our, uh, next question,

191
00:08:50.830 --> 00:08:53.630
Fred Watson, comes from Casey,

192
00:08:53.710 --> 00:08:56.030
who sent us an audio question.

193
00:08:57.080 --> 00:09:00.040
Professor Fred Watson: Hi guys, this is Casey from Colorado again. And today

194
00:09:00.040 --> 00:09:02.440
I have a question about tidally locked planets.

195
00:09:03.000 --> 00:09:05.840
I know that a tidally locked planet is a planet that

196
00:09:05.840 --> 00:09:08.600
always has the same side facing its star and that this

197
00:09:08.600 --> 00:09:11.120
happens because the orbital and

198
00:09:11.120 --> 00:09:13.880
rotational periods are the same. What I'm

199
00:09:13.880 --> 00:09:16.840
wondering about is how this might affect the formation of

200
00:09:16.840 --> 00:09:19.720
compounds and molecules. I hope you're both

201
00:09:19.720 --> 00:09:22.680
well and thank you for taking the time to answer so many of my

202
00:09:22.680 --> 00:09:23.160
questions.

203
00:09:23.320 --> 00:09:26.280
Andrew Dunkley: Thank you, Casey. It's lovely to hear from the ladies. I know there was a

204
00:09:26.280 --> 00:09:29.140
big push on to get more, uh, female listeners. Listeners to,

205
00:09:29.310 --> 00:09:32.260
um, send in questions. Uh, and that seems

206
00:09:32.260 --> 00:09:34.900
to have been very successful. So well done, Heidi.

207
00:09:35.310 --> 00:09:37.940
Uh, yeah. So what is the answer to

208
00:09:37.940 --> 00:09:39.060
Casey's query?

209
00:09:39.970 --> 00:09:42.260
Professor Fred Watson: Um, I think it's a great question actually.

210
00:09:42.660 --> 00:09:45.660
These, yeah, the, um, you know, if you've got

211
00:09:45.660 --> 00:09:48.660
a planet always has one side facing

212
00:09:49.140 --> 00:09:51.620
its parent star, that side is going to be pretty hot.

213
00:09:52.020 --> 00:09:54.650
But the other side is facing the

214
00:09:54.970 --> 00:09:57.970
depths of space. It's facing the cold of space and it could

215
00:09:57.970 --> 00:10:00.410
be pretty cold. You know, you could be way below

216
00:10:01.290 --> 00:10:04.250
zero, perhaps 200 degrees below zero on

217
00:10:04.250 --> 00:10:07.250
one side and perhaps 100 or 200 degrees above zero

218
00:10:07.250 --> 00:10:10.070
on the other. Um, so, um,

219
00:10:10.730 --> 00:10:13.570
molecules, for molecules and compounds to

220
00:10:13.570 --> 00:10:16.290
form, uh, they're like sort of

221
00:10:16.290 --> 00:10:18.970
moderate temperatures. Temperatures measured

222
00:10:19.530 --> 00:10:22.410
in tens, hundreds, maybe thousands of degrees.

223
00:10:22.410 --> 00:10:24.600
Knots tens of thousands of degrees.

224
00:10:25.160 --> 00:10:27.960
So, um, you might find that compounds are not going to form,

225
00:10:28.670 --> 00:10:31.480
uh, on the sun facing, on the star

226
00:10:31.480 --> 00:10:34.440
facing side of the planet because it's too hot.

227
00:10:35.320 --> 00:10:38.240
Compounds, uh, just get shredded apart

228
00:10:38.240 --> 00:10:41.040
into their component atoms by the energy of the

229
00:10:41.040 --> 00:10:43.910
heat. On the other side, it's too cold. Uh,

230
00:10:43.960 --> 00:10:46.800
so your, your molecules never kind of

231
00:10:46.800 --> 00:10:49.400
get together. There's not enough motion of the gases

232
00:10:50.120 --> 00:10:53.080
in an atmosphere for the molecules to come together and react

233
00:10:53.400 --> 00:10:56.150
but, but, uh, in between the two is

234
00:10:56.150 --> 00:10:58.870
this region that we always call the terminator. That's the

235
00:10:58.870 --> 00:11:01.830
region between the light side of a planet or

236
00:11:01.830 --> 00:11:04.750
the boundary between the light side of a planet and its dark side. And it

237
00:11:04.750 --> 00:11:07.350
could well be because the planet's not rotating.

238
00:11:07.830 --> 00:11:10.230
You might find that there the temperatures, ah, are

239
00:11:10.710 --> 00:11:13.630
sort of, you know, temperate, uh, all the

240
00:11:13.630 --> 00:11:16.270
time, um, promoting the formation of

241
00:11:16.270 --> 00:11:19.150
molecules and compounds. So for a

242
00:11:19.150 --> 00:11:22.110
tidally locked planet, it is possible that you could have

243
00:11:22.110 --> 00:11:24.910
this zone around the terminator which is quite rich in

244
00:11:24.910 --> 00:11:27.610
chemical reactions, action. So, um, yeah,

245
00:11:27.610 --> 00:11:30.530
Casey, I think you're onto something there. Maybe there will be this

246
00:11:30.530 --> 00:11:33.370
zone that might be habitable even in what looks

247
00:11:33.370 --> 00:11:36.290
like an otherwise uninhabitable world, because one side's too

248
00:11:36.290 --> 00:11:39.050
hot and the other side's too cold. Ah, you might find there's a

249
00:11:39.050 --> 00:11:41.170
zone that's not so. Yeah, good question.

250
00:11:41.970 --> 00:11:44.610
Andrew Dunkley: Excellent question. Thank you, Casey. And keep them coming.

251
00:11:44.610 --> 00:11:47.250
And, um, yeah, good to hear from you. And, uh,

252
00:11:47.570 --> 00:11:50.290
you know, when it comes to, um, dealing with,

253
00:11:50.880 --> 00:11:53.770
uh, extreme cold, uh, I'm sure you handle it well

254
00:11:53.770 --> 00:11:55.650
in Colorado. I don't know how you do it.

255
00:11:57.510 --> 00:12:00.350
Okay, okay. Um. Like, we were in Iceland

256
00:12:00.350 --> 00:12:03.270
in summer, and I think the maximum temperature was 6

257
00:12:03.270 --> 00:12:06.190
degrees. Uh, and I thought, if that's

258
00:12:06.190 --> 00:12:08.950
summer, I would hate to be here in winter. That was,

259
00:12:09.000 --> 00:12:11.909
uh, quite strange. But then. Not sure if I

260
00:12:11.909 --> 00:12:14.870
told you, Fred Watson, but we. When we were at North Cape in Norway,

261
00:12:14.870 --> 00:12:17.390
the northernmost tip of Europe, it was

262
00:12:17.390 --> 00:12:19.670
28 degrees that day.

263
00:12:20.230 --> 00:12:22.870
And I looked up the weather records for North

264
00:12:22.870 --> 00:12:25.150
Cape, and the highest they'd ever recorded there was

265
00:12:25.150 --> 00:12:28.010
28.4 war. So we'd nearly hit it

266
00:12:28.410 --> 00:12:31.410
the day we were there. And the

267
00:12:31.410 --> 00:12:34.090
locals were freaking out, like they thought it was horrible.

268
00:12:34.570 --> 00:12:37.450
It's walking around, making. It was so hot. But,

269
00:12:37.480 --> 00:12:39.770
um, we just went, oh, isn't this lovely?

270
00:12:41.290 --> 00:12:43.850
Professor Fred Watson: So when we were there in, um. When we were there in January,

271
00:12:44.600 --> 00:12:47.490
uh, there was snow everywhere,

272
00:12:47.490 --> 00:12:50.170
but it was still unseasonably warm. Uh, it was

273
00:12:50.810 --> 00:12:53.730
some. It was probably more like 6 degrees, the 6 that you had

274
00:12:53.730 --> 00:12:56.660
in Iceland. Um, we tend to go to all these

275
00:12:56.660 --> 00:12:59.500
countries in the depths of winter so that we get the most darkness

276
00:12:59.500 --> 00:13:02.460
and we see the aurora. So you'll definitely have to

277
00:13:02.460 --> 00:13:05.420
come with us sometime, Andrew, uh, because we always see it.

278
00:13:06.150 --> 00:13:08.940
Uh, and, um, um. Uh, that's why

279
00:13:08.940 --> 00:13:11.740
we're at North Cape. You know, when there was a matter

280
00:13:11.740 --> 00:13:14.660
of perhaps two or three hours of daylight. It was great,

281
00:13:14.660 --> 00:13:17.500
though, up there. And you would have stood by that huge

282
00:13:17.500 --> 00:13:20.380
analemosphere. That's right. At the tip of the North,

283
00:13:20.690 --> 00:13:23.130
North Cape. Um, we saw that in

284
00:13:23.130 --> 00:13:25.930
twilight. Uh, but yes, it was still

285
00:13:25.930 --> 00:13:28.870
unseasonably warm. It was snow. There was snow everywhere. Uh,

286
00:13:28.870 --> 00:13:30.690
but it was um, certainly above zero.

287
00:13:31.410 --> 00:13:34.210
Andrew Dunkley: Yeah, it's an incredible place. It's certainly um, you know one of

288
00:13:34.210 --> 00:13:37.210
those like we, we went around the southern tip of

289
00:13:37.210 --> 00:13:40.210
Africa which is right, um, the Cape of Good Hope right down

290
00:13:40.290 --> 00:13:43.210
south. And then you know, a month later

291
00:13:43.210 --> 00:13:46.010
we're standing on the northern tip of Europe. Yeah, caught

292
00:13:46.010 --> 00:13:48.820
it. Quite an incredible trip. Thanks Casey. Great to hear

293
00:13:48.820 --> 00:13:51.540
from you. This is Space Nuts with Andrew Dunkley and

294
00:13:51.540 --> 00:13:52.780
Professor Fred Watson Watson.

295
00:13:55.820 --> 00:13:58.060
Three, two, one.

296
00:13:58.620 --> 00:14:01.620
Space Nuts. And you're listening to a Q and

297
00:14:01.620 --> 00:14:04.300
A edition. And our next question comes from

298
00:14:04.460 --> 00:14:05.180
Hazel.

299
00:14:05.800 --> 00:14:08.700
Uh, and Hazel uh, says hi. I think we've all

300
00:14:08.700 --> 00:14:11.700
heard the musical adaption of orbits in the solar

301
00:14:11.700 --> 00:14:14.340
system sonification and how it highlights the

302
00:14:14.340 --> 00:14:16.780
beautiful resonance. And she says I love this.

303
00:14:17.400 --> 00:14:20.260
Uh, my question is to do with uh,

304
00:14:20.280 --> 00:14:23.120
most orbiting things. Uh, do most

305
00:14:23.120 --> 00:14:26.000
orbiting things experience this? Would

306
00:14:26.000 --> 00:14:28.840
galaxies orbiting their centre of mass also

307
00:14:28.840 --> 00:14:31.480
experience this? I feel Kepler in his

308
00:14:31.480 --> 00:14:34.399
genius got the um, uh, got to the bottom of

309
00:14:34.399 --> 00:14:36.920
this. But I find it fascinating. Love the show.

310
00:14:37.080 --> 00:14:39.480
Much love to you all. Hazel from Scotland.

311
00:14:40.280 --> 00:14:43.080
Scotland. What a lovely place that is. Rained all the time.

312
00:14:43.480 --> 00:14:46.330
Uh, but anyway, um, while

313
00:14:46.330 --> 00:14:49.290
we were there anyway I uh, remember us

314
00:14:49.340 --> 00:14:52.050
um, actually playing some of that sonification

315
00:14:52.050 --> 00:14:54.960
production where they took a photo, uh,

316
00:14:54.970 --> 00:14:57.810
wide angle photo or, or

317
00:14:57.810 --> 00:15:00.010
image of a portion of the universe

318
00:15:00.490 --> 00:15:02.810
and they applied sounds to this,

319
00:15:03.450 --> 00:15:06.330
the different objects and created this beautiful music.

320
00:15:06.970 --> 00:15:09.530
So would that apply elsewhere,

321
00:15:09.980 --> 00:15:11.610
uh, in other parts of the universe?

322
00:15:12.320 --> 00:15:15.160
Professor Fred Watson: Uh, so yes. So the tonifications that Hazel's

323
00:15:15.160 --> 00:15:18.080
talking about are a little bit different from that. And um, you

324
00:15:18.080 --> 00:15:18.400
know, I.

325
00:15:18.400 --> 00:15:20.320
Andrew Dunkley: Is this something I missed while I was away?

326
00:15:21.030 --> 00:15:23.760
Professor Fred Watson: Um, no you didn't. Oh,

327
00:15:23.760 --> 00:15:25.630
okay. Um, um, um.

328
00:15:26.960 --> 00:15:29.720
When, when I read Hazel's question I went to

329
00:15:29.720 --> 00:15:32.360
that. Exactly the picture that you're talking about. There's one that I

330
00:15:32.360 --> 00:15:35.240
particularly like. It's the galactic centre and all the stardust.

331
00:15:35.240 --> 00:15:38.240
Yeah, that's LinkedIn the less beautiful. And uh, it's still, it's pretty

332
00:15:38.240 --> 00:15:41.060
easy to find. It's on NASA's website. But what

333
00:15:41.060 --> 00:15:44.060
Hazel's talking about is the

334
00:15:44.380 --> 00:15:47.340
resonances between the

335
00:15:47.500 --> 00:15:50.500
planets. Uh, for example in a solar

336
00:15:50.500 --> 00:15:53.180
system. So that you've got a situation where

337
00:15:53.500 --> 00:15:55.260
one planet goes around once.

338
00:15:56.010 --> 00:15:58.860
Uh, uh, the one next to it

339
00:15:58.860 --> 00:16:01.580
on the inside goes around twice in the same time.

340
00:16:02.140 --> 00:16:04.980
The one on the outside of it goes around a half in the

341
00:16:04.980 --> 00:16:07.550
same time. So there's this uh. What we call

342
00:16:07.550 --> 00:16:10.350
orbital resonances. And you can sonify.

343
00:16:11.310 --> 00:16:14.310
Yeah, you can sonificate that. Uh, and in a

344
00:16:14.310 --> 00:16:16.790
sense it's what um, Kepler was doing when he wrote

345
00:16:16.790 --> 00:16:19.750
Harmonium Mundi, the Harmony of the Spheres or

346
00:16:19.750 --> 00:16:22.510
the harmony of the Worlds. Uh, he was looking

347
00:16:22.510 --> 00:16:24.430
at all these different

348
00:16:24.990 --> 00:16:27.830
resonances. Um, and the most obvious in our solar

349
00:16:27.830 --> 00:16:30.790
system is with some of the moons

350
00:16:30.790 --> 00:16:33.670
of Jupiter. Ganymede, Europa and IO are

351
00:16:33.670 --> 00:16:36.110
in a 4, 2 and 1 resonance with EO.

352
00:16:36.630 --> 00:16:39.470
Ganymede, um, 4 to 1, Europa, 2 to 1,

353
00:16:39.523 --> 00:16:42.150
EO, 1 to 1. So um, that's

354
00:16:42.310 --> 00:16:44.790
basically uh, the sort of thing that

355
00:16:45.440 --> 00:16:48.230
ah, Kepler was looking at because he said, well this is very

356
00:16:48.230 --> 00:16:51.230
similar to the. You know, the intervals on a

357
00:16:51.230 --> 00:16:53.830
musical scale where you've got fourths and fifths and

358
00:16:53.910 --> 00:16:56.790
these make chords that are pleasant to our ears. And so

359
00:16:56.790 --> 00:16:59.590
his harmony of the worlds was based on all that.

360
00:16:59.750 --> 00:17:02.590
But now we've got so many more examples

361
00:17:02.590 --> 00:17:05.450
with these extra, um, extrasolar

362
00:17:05.530 --> 00:17:08.250
planets. Uh, and there are some of them that have

363
00:17:08.250 --> 00:17:11.050
got really quite spectacular resonances.

364
00:17:11.770 --> 00:17:14.490
And I might refer, Hazel, to a very

365
00:17:14.490 --> 00:17:17.050
nice article that uh, appeared on the

366
00:17:17.450 --> 00:17:20.369
Conversation a year last February. It's written by a good friend

367
00:17:20.369 --> 00:17:22.970
of mine, Chris Impey. He and I were research students together

368
00:17:23.130 --> 00:17:25.730
actually in Edinburgh at the um, University of

369
00:17:25.730 --> 00:17:27.690
Edinburgh. Chris, uh, has been the.

370
00:17:29.610 --> 00:17:32.610
Chris has been. Ah, I'm glad you went there. It's good

371
00:17:32.610 --> 00:17:35.370
that you especially had haggis. I think that was very good for you.

372
00:17:35.830 --> 00:17:38.710
Uh, Lewis as basically

373
00:17:38.710 --> 00:17:41.630
most of his career as I've worked in Australia, he's worked in

374
00:17:41.630 --> 00:17:44.550
the United States principally at the University of Arizona where he's

375
00:17:44.550 --> 00:17:47.390
a distinguished professor of astronomy. Um,

376
00:17:47.430 --> 00:17:50.150
but he's written a lovely article on exactly this.

377
00:17:50.650 --> 00:17:53.190
Uh, it is called orbital resonance. The

378
00:17:53.190 --> 00:17:55.990
striking gravitational dance done by planets

379
00:17:55.990 --> 00:17:58.670
with aligning orbits. And it's worth looking

380
00:17:58.670 --> 00:18:00.950
at because Hazel, because it's got

381
00:18:01.450 --> 00:18:04.360
um, a list of uh, several

382
00:18:04.520 --> 00:18:07.390
of the major resonances around uh,

383
00:18:07.810 --> 00:18:10.360
uh, planets going around other stars like

384
00:18:10.360 --> 00:18:13.280
Gliese 876 which has got some 4 to

385
00:18:13.280 --> 00:18:16.080
2 to 1 orbital ratios. Kepler

386
00:18:16.080 --> 00:18:19.039
2:3, 3:4 planets with ratios of 8 to 6

387
00:18:19.039 --> 00:18:21.720
to 4 to 3. Uh, and there's a number

388
00:18:21.800 --> 00:18:24.680
of them. Uh, Trappist 1 is the record holder.

389
00:18:24.680 --> 00:18:27.440
It's got seven Earth like planets, um, with

390
00:18:27.440 --> 00:18:30.240
orbit ratios you don't need to know. It's uh. Well, it's

391
00:18:30.240 --> 00:18:32.840
24 to 15 to 9 to 6 to 4 to 3 to 2.

392
00:18:33.390 --> 00:18:36.350
So those are all what we call resonances. And

393
00:18:36.350 --> 00:18:39.060
you can turn them uh, into music. Uh,

394
00:18:39.070 --> 00:18:41.710
and uh, you can have orbital Sonification.

395
00:18:41.870 --> 00:18:44.670
And so Chris's article has got some nice links

396
00:18:44.670 --> 00:18:47.550
to the sonification of these orbits. There's a

397
00:18:47.550 --> 00:18:50.150
very nice one that, uh, eso, the European Southern

398
00:18:50.150 --> 00:18:52.750
Observatory, has done on one of the systems that,

399
00:18:53.250 --> 00:18:56.150
um, they've found. I think it's, um. Can't remember which

400
00:18:56.150 --> 00:18:58.970
system it is. I think it's tri178. Uh,

401
00:18:59.230 --> 00:19:01.740
you'll find a lovely audio of that. Um.

402
00:19:02.670 --> 00:19:05.650
Uh. If we'd been better organised, Andrew, we might have dug one of these out

403
00:19:05.650 --> 00:19:08.650
and, uh, played it for the show. Uh, but anyway,

404
00:19:08.730 --> 00:19:11.690
that's the place to look. It's a great article. It explains it very

405
00:19:11.690 --> 00:19:12.170
clearly.

406
00:19:12.330 --> 00:19:15.070
Your question about, um. Uh. Uh,

407
00:19:15.070 --> 00:19:17.930
resonances in galactic orbits is very

408
00:19:17.930 --> 00:19:20.090
much less easy to answer.

409
00:19:20.410 --> 00:19:23.050
Uh, we suspect not because,

410
00:19:23.890 --> 00:19:26.450
um, the number of stars in orbit around the

411
00:19:26.450 --> 00:19:29.290
galactic centre, 3 or 400 billion, means

412
00:19:29.290 --> 00:19:32.290
it's more like a cloud of particles, um, that behave in

413
00:19:32.290 --> 00:19:35.230
a different way from what individual objects do. It's

414
00:19:35.230 --> 00:19:37.910
more like a cloud of stuff going around the centre of the galaxy

415
00:19:38.070 --> 00:19:40.750
rather than specific planets with their own centre of mass

416
00:19:40.750 --> 00:19:43.270
and their own resonances. So I don't think

417
00:19:43.750 --> 00:19:46.190
there are, uh, resonances to be found in

418
00:19:46.190 --> 00:19:49.070
galactic orbits. I'm happy to be proved wrong,

419
00:19:49.070 --> 00:19:51.110
though. Yeah.

420
00:19:51.190 --> 00:19:52.550
Andrew Dunkley: Never say never for any.

421
00:19:52.550 --> 00:19:54.630
Professor Fred Watson: I think it's never say never. That's right, yeah.

422
00:19:55.590 --> 00:19:58.390
Andrew Dunkley: Yeah. Wonderful. Uh, Hazel, thank

423
00:19:58.390 --> 00:19:59.710
you. And, um.

424
00:19:59.930 --> 00:20:00.020
Professor Fred Watson: Um.

425
00:20:00.700 --> 00:20:03.660
Andrew Dunkley: I. I must say I loved Scotland while I was there. It

426
00:20:03.660 --> 00:20:06.580
was a brief visit but, um, I'm glad I got to see it and.

427
00:20:06.580 --> 00:20:09.420
And travel, uh, from Glasgow across to

428
00:20:09.420 --> 00:20:12.220
Edinburgh and back. Um. Yeah,

429
00:20:12.220 --> 00:20:15.180
lovely part of the world. Even that was cold and wet and.

430
00:20:15.660 --> 00:20:18.140
Yeah, well, it wasn't windy. That's the only.

431
00:20:18.300 --> 00:20:21.220
Wasn't too windy, but the rest of it was. It

432
00:20:21.220 --> 00:20:24.140
was supposed to be summer, Fred Watson. I don't. You know, I

433
00:20:24.140 --> 00:20:27.020
don't know how people live in the northern. Now most of the world population

434
00:20:27.020 --> 00:20:29.820
lives in the northern hemisphere and from my experience,

435
00:20:29.900 --> 00:20:31.660
the weather's so much worse up there.

436
00:20:33.180 --> 00:20:36.020
Professor Fred Watson: If you, um. Yes, that's right. If you, um, drove on the

437
00:20:36.020 --> 00:20:38.460
M9, as you probably did, if you went by car from,

438
00:20:38.540 --> 00:20:41.500
uh, Glasgow to Edinburgh, you would have passed the Kelpies.

439
00:20:42.460 --> 00:20:45.420
Uh. Would you have passed the Kelpies? Yes, you would. I think they're on that

440
00:20:45.420 --> 00:20:48.100
road. Two huge

441
00:20:48.100 --> 00:20:51.060
statues of Celtic water horses. You might

442
00:20:51.060 --> 00:20:51.660
have seen them.

443
00:20:51.900 --> 00:20:54.620
Andrew Dunkley: Yeah. There's also sculptures along there, like

444
00:20:55.500 --> 00:20:57.060
a whole bunch of different things.

445
00:20:57.060 --> 00:20:57.500
Professor Fred Watson: Yes.

446
00:20:57.500 --> 00:20:59.580
Andrew Dunkley: Yeah, we did spot a few along the way.

447
00:20:59.900 --> 00:21:00.260
Professor Fred Watson: Yes.

448
00:21:00.260 --> 00:21:02.960
Andrew Dunkley: It's quite weird ones. They got a great sculpture in

449
00:21:02.960 --> 00:21:05.160
Glasgow of, um. 2 is it.

450
00:21:05.160 --> 00:21:07.160
Professor Fred Watson: Ship builders. I think they were ship builders.

451
00:21:08.040 --> 00:21:10.720
Andrew Dunkley: Um, humongous things with giant

452
00:21:10.720 --> 00:21:13.600
sledgehammers. Yeah, it was. That's. That was a beautiful

453
00:21:13.600 --> 00:21:16.560
statue as well. M. Uh, thanks, Hazel. Great

454
00:21:16.560 --> 00:21:17.320
to hear from you.

455
00:21:20.120 --> 00:21:22.360
Three, two, one.

456
00:21:22.920 --> 00:21:24.200
Space nuts.

457
00:21:24.440 --> 00:21:27.200
Our final question. Oh, good grief. Here we

458
00:21:27.200 --> 00:21:28.360
go. Comes from

459
00:21:29.960 --> 00:21:30.520
Rusty.

460
00:21:30.760 --> 00:21:33.600
Rusty: Hey, Fred Watson. And Andrew. And maybe Heidi. It's

461
00:21:33.600 --> 00:21:34.760
Rusty and Donnybrook.

462
00:21:36.280 --> 00:21:38.880
I'll try and keep it simple as I always do. The

463
00:21:38.880 --> 00:21:41.640
peculiar motion of the Local Group towards the Virgo

464
00:21:41.640 --> 00:21:44.400
Cluster and onwards to the Great Attractor. Uh, in the Hydro

465
00:21:44.400 --> 00:21:47.240
Centaurus supercluster. Turns out to be

466
00:21:47.240 --> 00:21:49.880
the same as the overall supercluster itself.

467
00:21:50.360 --> 00:21:53.320
When observed in a co moving reference

468
00:21:53.320 --> 00:21:56.010
frame where the observer is at rest

469
00:21:56.010 --> 00:21:57.570
relative to the cmb.

470
00:21:59.490 --> 00:22:02.160
Now the, uh, Lambda CDM M

471
00:22:03.010 --> 00:22:05.690
is invoked to explain this enormous peculiar

472
00:22:05.690 --> 00:22:08.570
flow. Space

473
00:22:08.570 --> 00:22:11.250
was already effectively infinite when matter first

474
00:22:11.250 --> 00:22:14.050
appeared. 380,000 years after the Big Bang.

475
00:22:15.010 --> 00:22:17.890
If we look at explosions in the vacuum of space, for example

476
00:22:17.890 --> 00:22:20.570
a Crab Nebula, we find filaments and

477
00:22:20.570 --> 00:22:23.340
voids. But in the everywhere all at

478
00:22:23.340 --> 00:22:25.900
once explosive birth of matter. In the

479
00:22:25.900 --> 00:22:27.700
highly energetic universe,

480
00:22:28.500 --> 00:22:30.940
resulting flows could have happened in any

481
00:22:30.940 --> 00:22:33.820
direction. Could this be what we

482
00:22:33.820 --> 00:22:36.340
are seeing? See, that's a simple question.

483
00:22:37.300 --> 00:22:39.060
Thanks, people. Cheers.

484
00:22:40.020 --> 00:22:42.420
Andrew Dunkley: Yeah, okay. Right.

485
00:22:42.980 --> 00:22:45.360
I see. Uh, thank you, Rusty. Uh,

486
00:22:46.340 --> 00:22:49.220
so good to hear from you. Um, my

487
00:22:49.220 --> 00:22:51.990
brain hurts, Fred Watson. I'm very confused.

488
00:22:52.420 --> 00:22:55.270
Professor Fred Watson: Uh, um, I was going to let you answer this one, Andrew. I thought

489
00:22:55.270 --> 00:22:56.230
you can talk to us.

490
00:22:57.270 --> 00:22:59.510
Andrew Dunkley: I've got an answer for him because.

491
00:23:00.550 --> 00:23:02.550
Professor Fred Watson: Yeah, um, there's a few.

492
00:23:03.590 --> 00:23:06.550
There's a lot in there that I'm not gonna unpick. Thank you,

493
00:23:06.550 --> 00:23:09.430
Rusty. Um, matter actually appeared in the first

494
00:23:09.430 --> 00:23:11.990
three minutes, not the first 380, 000 years.

495
00:23:12.520 --> 00:23:15.350
Uh, when, um, uh, the radiation

496
00:23:15.590 --> 00:23:17.810
got cool enough for atoms to form.

497
00:23:18.620 --> 00:23:21.330
Uh, yeah, so, so it didn't take very long.

498
00:23:21.780 --> 00:23:24.730
Um, and you're absolutely

499
00:23:24.730 --> 00:23:27.450
right to, uh, quote the

500
00:23:27.450 --> 00:23:30.080
filaments because that's what happened. Uh,

501
00:23:30.210 --> 00:23:32.330
we think that. And

502
00:23:32.330 --> 00:23:34.850
notwithstanding the peculiar motion of

503
00:23:34.850 --> 00:23:37.730
galaxies, um, which is basically just

504
00:23:37.730 --> 00:23:40.130
the, the gravitational pull of

505
00:23:40.370 --> 00:23:43.060
these filaments of, of dark matter

506
00:23:43.060 --> 00:23:45.980
probably that's uh, moving them around relative

507
00:23:45.980 --> 00:23:48.820
to the expansion of the universe. Relative to what we call the Hubble

508
00:23:48.820 --> 00:23:51.580
flow, um, those filaments seem to have been

509
00:23:51.580 --> 00:23:54.180
created very early, uh, in the

510
00:23:54.180 --> 00:23:57.100
expansion of the universe. Maybe during the period of inflation, which

511
00:23:57.100 --> 00:23:59.700
is the first gazillionth of a second. Forget three

512
00:23:59.700 --> 00:24:02.660
minutes. It's 10 to the minus 33, I think is

513
00:24:02.660 --> 00:24:05.580
the number. Um, so, um, I

514
00:24:05.580 --> 00:24:08.510
think the way to look at it, I remember, um,

515
00:24:09.180 --> 00:24:11.980
uh, My young, uh, nephew some time

516
00:24:11.980 --> 00:24:14.140
ago, uh, playing with some stuff that

517
00:24:14.700 --> 00:24:17.020
was. It's kind of like play doh.

518
00:24:17.020 --> 00:24:17.500
Andrew Dunkley: I think.

519
00:24:18.020 --> 00:24:20.780
Professor Fred Watson: Uh, and he sort of squashed this stuff,

520
00:24:20.860 --> 00:24:23.780
a lump of this stuff down, uh, between the

521
00:24:23.780 --> 00:24:26.460
table in his hand. And then lifted it his hand up.

522
00:24:26.460 --> 00:24:29.420
And what you got was spontaneously forming

523
00:24:29.420 --> 00:24:31.820
filaments linking one blob to the other.

524
00:24:32.460 --> 00:24:35.360
And uh, it's just. That's seems to be

525
00:24:35.520 --> 00:24:37.920
uh, a facet of something that's

526
00:24:37.920 --> 00:24:40.080
expanding. You, uh, will get

527
00:24:41.040 --> 00:24:43.520
it probably depends on viscosity. And

528
00:24:43.840 --> 00:24:46.840
well, space time doesn't have any viscosity. We discussed

529
00:24:46.840 --> 00:24:49.520
that in the last Q A session of

530
00:24:49.600 --> 00:24:52.240
uh, of uh, space Notes. But it's

531
00:24:52.240 --> 00:24:55.080
still light. It did form filaments and we, we can see

532
00:24:55.080 --> 00:24:58.000
them today. We see the structure of galaxies on the.

533
00:24:58.000 --> 00:25:00.550
On a much wider scale than we're talking about the Virgo

534
00:25:01.020 --> 00:25:03.900
Cluster, which is really nearby. Um, you

535
00:25:03.900 --> 00:25:06.660
see these, this filamentary, this kind of foam

536
00:25:06.660 --> 00:25:09.500
like structure of the universe. Which seems to just

537
00:25:09.500 --> 00:25:12.440
have been an artefact of the expansion, uh,

538
00:25:12.440 --> 00:25:15.180
caused because of slight differences in

539
00:25:15.180 --> 00:25:18.060
temperature in the Big Bang plasma.

540
00:25:18.180 --> 00:25:21.180
Um, and so the dark matter seems to form

541
00:25:21.180 --> 00:25:23.500
these filaments. The clouds of hydrogen

542
00:25:23.660 --> 00:25:26.620
collapsed onto them. That's where they form the galaxies. And

543
00:25:26.620 --> 00:25:29.600
that's why we're still seeing these galaxies strung out all

544
00:25:29.600 --> 00:25:32.560
over the place. Um, so it's not, you know, you

545
00:25:32.560 --> 00:25:35.240
don't need. Ah. You drew the

546
00:25:35.380 --> 00:25:38.240
um, example of the Crab Nebula. You're quite right. There's filaments everywhere

547
00:25:38.240 --> 00:25:41.240
with that. And they all seem to radiate out from the centre, the source of

548
00:25:41.240 --> 00:25:43.879
the explosion. But if you've just got an expansion,

549
00:25:44.300 --> 00:25:46.600
um, you don't need a particular

550
00:25:47.160 --> 00:25:50.160
direction for these filaments to form in. They'll just

551
00:25:50.160 --> 00:25:53.120
give you this sort of foam of material, um, which

552
00:25:53.120 --> 00:25:55.500
is what spacetime is like. And so,

553
00:25:55.500 --> 00:25:58.180
um, Uh, I don't know that that

554
00:25:58.180 --> 00:26:00.980
necessarily answers Rusty's question, but I hope it

555
00:26:00.980 --> 00:26:02.300
gives him some food for thought.

556
00:26:03.100 --> 00:26:03.580
Andrew Dunkley: Yes.

557
00:26:03.580 --> 00:26:04.340
Professor Fred Watson: Or it'll.

558
00:26:04.340 --> 00:26:06.100
Andrew Dunkley: Yeah, it'll just make him ask another question.

559
00:26:06.100 --> 00:26:08.940
That's. That's the problem, isn't it?

560
00:26:09.900 --> 00:26:12.580
Professor Fred Watson: No, it's great. It's great that we get these. Oh, just

561
00:26:12.580 --> 00:26:14.380
kidding. Yeah. Yeah.

562
00:26:15.020 --> 00:26:17.660
Andrew Dunkley: Rusty actually sent me some great photos while I was away

563
00:26:17.660 --> 00:26:20.470
of uh, I think a couple of planets that.

564
00:26:20.540 --> 00:26:23.340
That uh, he observed. Oh. Great night

565
00:26:24.300 --> 00:26:27.220
out of Wa. So, uh. Yeah, it was good. So thanks

566
00:26:27.220 --> 00:26:30.060
for that, Rusty. Um, um, but always

567
00:26:30.060 --> 00:26:33.060
great to hear from you. Your questions are always so far out

568
00:26:33.060 --> 00:26:34.780
of left field. I don't. Yeah,

569
00:26:37.020 --> 00:26:40.020
that's too much. For my brain. Uh, but

570
00:26:40.020 --> 00:26:43.020
thanks Rusty. Good, uh, to hear from you as always.

571
00:26:43.100 --> 00:26:45.940
And please keep the questions coming in, female and

572
00:26:45.940 --> 00:26:48.840
male listeners alike. Uh, we, we love to

573
00:26:48.840 --> 00:26:51.720
hear from, from everybody. Uh, so

574
00:26:51.720 --> 00:26:54.600
just go uh, to our website and um, and send them

575
00:26:54.600 --> 00:26:57.320
in to us. Space, uh, nuts

576
00:26:57.320 --> 00:27:00.280
podcast.com or Space Nuts IO is where

577
00:27:00.280 --> 00:27:03.200
you can send text and audio questions. And while you're online,

578
00:27:03.360 --> 00:27:06.320
jump, jump around our website and have a look. I don't think anyone's

579
00:27:06.320 --> 00:27:08.720
been into the shop for months. So, um,

580
00:27:09.120 --> 00:27:11.920
Huw's just sitting in there surfing the Internet and

581
00:27:12.000 --> 00:27:14.890
trying to um, figure out the problems of the world.

582
00:27:14.890 --> 00:27:15.130
Professor Fred Watson: So.

583
00:27:15.130 --> 00:27:18.130
Andrew Dunkley: Well, you know, um, go and sell something here, for crying out

584
00:27:18.130 --> 00:27:20.570
loud. Uh, but yes, uh, that's on our website.

585
00:27:21.440 --> 00:27:24.290
Uh, and we're on Facebook and Instagram as well. If you're

586
00:27:24.290 --> 00:27:27.250
into social media, you can follow us there. You don't. Yeah,

587
00:27:27.250 --> 00:27:30.130
no obligation. You don't have to do anything. You don't have to talk to

588
00:27:30.130 --> 00:27:32.930
anybody. Just look at the picture. Uh, that's how

589
00:27:32.930 --> 00:27:35.690
I studied at school. Look at the pictures. Yes, that's,

590
00:27:36.010 --> 00:27:38.490
that's enough. Uh, but, uh, yes,

591
00:27:38.860 --> 00:27:41.540
um, spacenutspodcast.com spacenats

592
00:27:41.620 --> 00:27:44.460
IO or facebook.com space nuts or the

593
00:27:44.460 --> 00:27:47.380
Space Nuts podcast group is another,

594
00:27:47.720 --> 00:27:50.420
um, group that's very much worth

595
00:27:50.420 --> 00:27:53.340
following because that's where most of our listeners talk to

596
00:27:53.340 --> 00:27:56.100
each other. If you want to join in. Um, that's enough jibber

597
00:27:56.100 --> 00:27:57.540
jabber from me. Thank you Fred Watson.

598
00:27:57.540 --> 00:28:00.540
Professor Fred Watson: As always, great stuff, Andrew. I look

599
00:28:00.540 --> 00:28:02.580
forward to doing it all again next week.

600
00:28:03.380 --> 00:28:06.270
Andrew Dunkley: Indeed. Uh, Professor Fred Watson Watson, astronomer

601
00:28:06.270 --> 00:28:09.260
at large, and thanks to Huw in the studio, uh,

602
00:28:09.260 --> 00:28:12.150
who couldn't be with us today because, um, well, he's

603
00:28:12.150 --> 00:28:15.030
a bulk motion in the universe and they're

604
00:28:15.030 --> 00:28:17.910
pretty slow. And from me, Andrew Dunkley. Thanks for your

605
00:28:17.910 --> 00:28:20.670
company. Catch you on the next episode of Space Nuts. Bye

606
00:28:20.670 --> 00:28:20.990
bye.

607
00:28:22.190 --> 00:28:24.990
Voice Over Guy: You've been listening to the Space Nuts podcast

608
00:28:26.510 --> 00:28:29.310
available at Apple Podcasts, Spotify,

609
00:28:29.470 --> 00:28:32.310
iHeartRadio radio or your favourite podcast

610
00:28:32.310 --> 00:28:34.030
player. You can also stream on

611
00:28:34.030 --> 00:28:36.990
demand at bitesz.com this has been another

612
00:28:36.990 --> 00:28:38.990
quality podcast production from

613
00:28:38.990 --> 00:28:40.190
bitesz.com