#406: Celestial Choreography & Speedy Snapshots: Deciphering Distant Star Systems & The Challenge of Cosmic Photography

WEBVTT

1
00:00:00.320 --> 00:00:03.319
Hi there, thanks for joining us
on Space Nuts, Q and A.

2
00:00:03.560 --> 00:00:06.839
My name is Andrew Dunkley, your
host. It's great to have your company,

3
00:00:07.519 --> 00:00:11.519
and we thank our audience for sending
in questions. We've got some new

4
00:00:11.560 --> 00:00:13.720
ones the other day, so we're
going to try and knock off a few

5
00:00:13.759 --> 00:00:19.280
of those in this episode. Viano
has got in touch with us this week.

6
00:00:20.160 --> 00:00:26.839
He's asking questions about planets and photographing
planets and missions to distant planets that

7
00:00:26.879 --> 00:00:31.760
we might be able to take a
look at, but will there be problems

8
00:00:31.800 --> 00:00:36.320
if we want to send back images. We've got a question from Brady,

9
00:00:36.759 --> 00:00:40.359
could a moon have a moon?
That is? That's a good question,

10
00:00:40.439 --> 00:00:45.719
let's look into that. And Scott
is asking about the star system HDF one

11
00:00:45.840 --> 00:00:49.799
one zero zero six seven. I'm
sure you know it well. We'll find

12
00:00:49.840 --> 00:00:56.880
out all about it this week on
Space Nuts. Fifteen second in channel ten

13
00:00:57.799 --> 00:01:07.200
nine ignition seek one space nuts or
three two space notes as when I re

14
00:01:07.319 --> 00:01:12.280
bought it. Neil's good and joining
us to tackle all of those questions with

15
00:01:14.359 --> 00:01:18.359
most insightful answers. Professor Fred what's
an astronomer at large? Hello Fred,

16
00:01:19.560 --> 00:01:23.319
Hello Andrew. Hopefully this will be
Q and A rather than Q and not

17
00:01:23.519 --> 00:01:30.640
A, which is always the risk. You know, it is a bit.

18
00:01:30.719 --> 00:01:36.200
But you know, even when we
get questions we can't answer, which

19
00:01:36.239 --> 00:01:42.040
we've actually received while we've been talking
today, we really chase them up if

20
00:01:42.079 --> 00:01:48.519
we can, so never never be
discouraged. We we do. We'd love

21
00:01:48.560 --> 00:01:51.040
to get your questions, and I
will tell you how to do that at

22
00:01:51.040 --> 00:01:53.920
the end. Let's go to our
first question, Fred, And this one,

23
00:01:55.120 --> 00:02:00.200
as I said, comes from Viano. Hey, guys, from Flo

24
00:02:00.480 --> 00:02:02.560
in Italy. So I have a
two questions for you. The first one

25
00:02:02.799 --> 00:02:07.439
is related to the break To project
with old us that they want to reach

26
00:02:07.519 --> 00:02:10.599
comoch entiality with the sort of solar
sale at around one speed of light,

27
00:02:12.159 --> 00:02:15.960
which I think it means more or
less one another kiln we just per second.

28
00:02:15.520 --> 00:02:19.680
I worked within the other cameras and
I know how difficult it is to

29
00:02:19.719 --> 00:02:25.479
find the right time configuration the optical
alensis focused and so on, and I

30
00:02:25.520 --> 00:02:29.879
was thinking that maybe it will not
be possible to take a clear picture of

31
00:02:29.919 --> 00:02:34.280
a planet if you're moving so fast
in front of What do you think about

32
00:02:34.319 --> 00:02:38.560
that? The second question is related
to the planet ORBITA. So can you

33
00:02:38.599 --> 00:02:44.080
please explain me what is that?
Defines the distance between the planet and stand

34
00:02:44.639 --> 00:02:49.960
so for sure there must be a
sort of gravity equilibrium, but I cannot

35
00:02:50.039 --> 00:02:54.000
understand why they are not in order
considering the mass or the envolumements, so

36
00:02:54.319 --> 00:02:59.319
there must be something else. And
so, guys, I started listening to

37
00:02:59.360 --> 00:03:02.879
you because of to learn us on
English. I'm pretty sure if my English

38
00:03:02.919 --> 00:03:07.199
is not so rude or in books, but based ont the looking at this

39
00:03:07.240 --> 00:03:10.120
guy, I love this US now
and I think it is great great,

40
00:03:10.520 --> 00:03:15.080
So thank you guys, my mate, Thanks Fiano. I'm a little bit

41
00:03:15.080 --> 00:03:21.680
disturbed that you think we're going to
be helpful with your English, but now

42
00:03:21.719 --> 00:03:24.520
I'm really pleased that you said us
a question. Your English is actually very

43
00:03:24.520 --> 00:03:31.960
good, and indeed we understood perfectly
what you were asking us. But thanks

44
00:03:32.000 --> 00:03:37.960
for sending in a question. It's
greatly appreciated. And having been in Florence

45
00:03:38.680 --> 00:03:43.159
fairly recently, what an amazing place
you live in, a beautiful part of

46
00:03:43.199 --> 00:03:46.639
the world. I happen to be
there at All Saints Weekend, which is

47
00:03:46.680 --> 00:03:51.240
a four day public holiday, and
there were thousands and thousands and thousands of

48
00:03:51.240 --> 00:03:54.680
people there. It was almost impossible
to move through the city square and see

49
00:03:54.719 --> 00:04:00.599
all the sites just everyone flocked to
Florence that weekend, big religious holiday.

50
00:04:01.039 --> 00:04:09.280
But what an amazing place. Yes, and beautiful part of Italy too.

51
00:04:09.360 --> 00:04:15.520
It's yeah, just extraordinary around there. Now he mentioned the Breakthrough project.

52
00:04:15.520 --> 00:04:23.560
This is the plan to send micro
spacecraft on a flyby of Alpha Centauri,

53
00:04:24.759 --> 00:04:30.839
the planets of Centaury B. Is
it? And they they won't be able

54
00:04:30.879 --> 00:04:34.839
to stop. I remember it's talking
about that. So let's just sort of

55
00:04:34.879 --> 00:04:40.800
review what Breakthrough is about and then
try and answer Viano's questions as to whether

56
00:04:40.879 --> 00:04:45.600
or not we'd be able to send
back a photo or two. This is

57
00:04:45.639 --> 00:04:49.040
actually a great question, and I
think there's quite a lot of subtlety to

58
00:04:49.160 --> 00:04:58.040
it. So it's a Breakthrough starshot
and that project was initiated by Uri Milna,

59
00:05:00.319 --> 00:05:04.879
billionaire who set up the Breakthrough Foundation
in order to study the possibilities of

60
00:05:04.959 --> 00:05:11.839
using light sales, laser driven light
sales to accelerate a spacecraft which might only

61
00:05:11.879 --> 00:05:15.560
weigh less than a kilogram, you
know, it's tiny stuff. We're talking

62
00:05:15.560 --> 00:05:21.759
about to a speed which would allow
you to reach Proxima Centaury, the nearest

63
00:05:21.800 --> 00:05:29.360
of the Alpha Centauri system, a
dwarf red dwarf star within a you know,

64
00:05:29.439 --> 00:05:33.720
within a reasonable number of years.
And so yeah, if you accelerate

65
00:05:33.800 --> 00:05:36.879
it to a third of the speed
of light one hundred thousand kilometers per seconds,

66
00:05:38.360 --> 00:05:44.360
as Fianna says, then you're probably
going to take I mean alone for

67
00:05:44.480 --> 00:05:47.079
acceleration and deceleration, you're probably going
to take less than twenty years to get

68
00:05:47.480 --> 00:05:54.639
your four light years away. And
that then you but then you faced with

69
00:05:55.399 --> 00:05:59.160
the issue and it probably wouldn't be
just one spacecraft. I think it will

70
00:05:59.199 --> 00:06:09.959
be a little flotilla of sail driven
spacecraft which would fly along the laser line

71
00:06:10.399 --> 00:06:17.360
accelerated. Sorry, there's the people
are people are complaining about our rooster Andrew.

72
00:06:17.399 --> 00:06:23.160
They think he's they think he's a
cockrel. He's not. He's a

73
00:06:23.240 --> 00:06:28.720
dog with a stupid voice. And
he does that when someone turns up.

74
00:06:29.040 --> 00:06:32.319
He does even when not when somebody
turns up, he just does it because

75
00:06:32.360 --> 00:06:39.240
it just doesn't occur. Well,
look, I've counseled him the nature of

76
00:06:39.720 --> 00:06:45.399
little terriers or little terrors, whichever
way you want to look at anyway,

77
00:06:46.839 --> 00:06:51.759
So yeah, you whizz through the
proximate centaury system and he does have planets

78
00:06:53.319 --> 00:06:58.480
one hundred thousand kilometers per second,
you've got cameras that are supposed to be

79
00:06:58.519 --> 00:07:01.560
able to photograph planets. You want
to photograph them in enough detail that you

80
00:07:01.560 --> 00:07:06.439
can actually see what's going on on
their surface. That is an incredibly difficult

81
00:07:06.480 --> 00:07:14.519
problem. The nearest thing I can
draw up parallel to, which was very

82
00:07:14.560 --> 00:07:23.079
successful was New Horizons fly by the
Poluto system back in twenty fifteen. Is

83
00:07:23.079 --> 00:07:28.160
that right? Fourteenth of July twenty
fifteen. I think that was it?

84
00:07:28.399 --> 00:07:34.720
Let me check brains, Yeah,
you check that, and the actually I

85
00:07:34.759 --> 00:07:40.959
might have the fourteen might be something
else, because my recollection is that the

86
00:07:41.120 --> 00:07:46.519
fly by velocity the fourteen was the
fourteenth of July twenty fifteen. There you

87
00:07:46.560 --> 00:07:50.240
go, that's got it right,
yeh. Check. Check the other figure

88
00:07:50.399 --> 00:07:54.160
for me, though, Andrew,
because I think, if I remember rightly,

89
00:07:54.199 --> 00:08:01.000
the fly by velocity was fourteen kilometers
per Second's yeah, I haven't got

90
00:08:01.040 --> 00:08:03.199
that, but I will look it
up now, okay, just to make

91
00:08:03.240 --> 00:08:11.720
sure. So, and that was
an amazing feat of engineering. Twenty three

92
00:08:11.800 --> 00:08:15.120
kilometers per second, okay, twenty
three, So I'm mixing up the fourteen

93
00:08:15.160 --> 00:08:22.360
of the day. Yeah, twenty
three kilometers per second. That are you

94
00:08:22.399 --> 00:08:24.959
sure that was the fly by velocity. That sounds more like the maximum velocity.

95
00:08:26.120 --> 00:08:31.159
Well, hang on, I'll keep
looking. Yeah, I think it.

96
00:08:31.240 --> 00:08:35.399
I think it was the fastest spacecraft
ever launched because at one point in

97
00:08:35.440 --> 00:08:43.200
its trajectory probably new horizons flew within
twelve and a half thousand kilometers of Pluto

98
00:08:43.240 --> 00:08:46.919
at a relative velocity of eleven kilometers
eleven Okay, that sounds more like it.

99
00:08:48.200 --> 00:08:52.039
Yes, eleven kilometers per second.
It's a very small percentage of one

100
00:08:52.080 --> 00:08:56.840
hundred thousand kilometers per second, which
is what the fly by speed will be

101
00:08:56.879 --> 00:09:07.360
for any breakthrough space shot star shot
initiatives. But it was highly successful what

102
00:09:07.399 --> 00:09:09.519
they had to do because you can't
control this in real time, Andrew,

103
00:09:09.600 --> 00:09:13.399
because you've got you know, I
can't remember what the time delay was,

104
00:09:13.440 --> 00:09:16.679
but it was minutes out to get
the signal out there, and this thing

105
00:09:16.720 --> 00:09:24.360
flashes by. So they had a
pre arranged sequence of shots the camera angles

106
00:09:24.440 --> 00:09:30.480
to get not just Pluto as if
as they flew by, but Pluto's moons,

107
00:09:30.519 --> 00:09:35.000
all of them, including the biggest
one care on they did. They

108
00:09:35.000 --> 00:09:43.799
did fantastic planning and built into the
engineering of this so that when you know,

109
00:09:43.840 --> 00:09:48.080
the spacecraft got within x thousand kilometers
of Pluto. This sequence started and

110
00:09:48.159 --> 00:09:54.399
it was executed perfectly. It was
just a choreographed set of imagery. And

111
00:09:54.480 --> 00:09:58.559
of course, I guess we're all
familiar with the dramatic pictures that were returned

112
00:10:01.080 --> 00:10:05.919
six hours be time delay six hours. There you go. Yeah, so

113
00:10:05.080 --> 00:10:09.840
thank you. I'm glad. It's
a long time ago. What's that it's

114
00:10:09.879 --> 00:10:16.720
nine years ago since all the Gift
talks I talked about about one hundred times,

115
00:10:16.759 --> 00:10:20.240
I think, so I knew the
numbers. But receding in the past

116
00:10:20.279 --> 00:10:26.120
anyway. So the issue that that
Vianna raises, we have a different set

117
00:10:26.120 --> 00:10:33.720
of circumstances here. We've got these
tiny little machines which have cameras on board

118
00:10:35.080 --> 00:10:39.279
pointing hopefully in the right direction.
You've got a four and a half year

119
00:10:39.399 --> 00:10:46.679
time lag back to Earth, so
there's no chance whatsoever of pointing the thing.

120
00:10:46.840 --> 00:10:50.200
It has to all be done robostically. So you can have sensors on

121
00:10:50.240 --> 00:10:54.960
board that will look for the brightest
object in the field of view and basically

122
00:10:54.039 --> 00:11:00.360
point your camera towards it. But
one hundred thousand kilometers per second, there

123
00:11:00.360 --> 00:11:05.639
are also what we call relativistic effects. The geometry of space changes, so

124
00:11:07.799 --> 00:11:11.080
you're not just taking you know,
saying that well, we know where these

125
00:11:11.080 --> 00:11:13.639
things are, we can point the
camera at them. You've got to take

126
00:11:13.679 --> 00:11:18.960
into account the fact that space is
distorted by the relative velocity one hundred thousand

127
00:11:18.000 --> 00:11:26.639
kilometers per second, third of the
speed of light, which will change the

128
00:11:26.720 --> 00:11:31.440
directions of the things that you're looking
in. It basically squash squashes the stars

129
00:11:31.480 --> 00:11:37.759
forward in your field of view in
that relativistic effect. So all those phenomena

130
00:11:37.200 --> 00:11:41.600
and I think, you know,
if the animal's amazing doubts about whether this

131
00:11:41.679 --> 00:11:45.120
is feasible, I think is right
on the money, because I think it

132
00:11:45.159 --> 00:11:50.480
is so difficult to do. We
don't even know whether the technology would work

133
00:11:50.519 --> 00:11:52.559
to get us there in that length
of time. But it's a very interesting

134
00:11:52.720 --> 00:11:58.679
problem and it's one that needs to
have interesting answers. Indeed, I mean

135
00:11:58.840 --> 00:12:05.240
buried and play. Other effects like
the distance of the planet from the stars,

136
00:12:07.120 --> 00:12:11.279
exposure times. Yeah, there's so
many other factors that need to be

137
00:12:11.279 --> 00:12:16.799
back and I'm sure the scientists involved
would take that into account, but there's

138
00:12:16.879 --> 00:12:18.759
certain things they won't be able to
control. And when you're talking robotics,

139
00:12:18.799 --> 00:12:22.279
once they're on their way, that's
it. You're not really going to be

140
00:12:22.279 --> 00:12:28.600
able to do much once they get
too far away to to take those photographs

141
00:12:28.639 --> 00:12:31.440
and transmit them back. You just
just going to sit and wait and hope

142
00:12:31.519 --> 00:12:35.399
and pray that it all works and
then four and a half years less you

143
00:12:35.399 --> 00:12:39.480
get your pictures. But yeah,
and it's just your lucky blob. Yeah.

144
00:12:41.360 --> 00:12:45.240
Now, the other bit of question
was about the orbits of planets,

145
00:12:45.559 --> 00:12:50.320
and it is. It's a great
it's you know why planet's in a particular

146
00:12:50.399 --> 00:12:58.879
orbit. There's the orbit is basically
dictated very much by the distance the two

147
00:13:00.080 --> 00:13:07.799
go completely together. In fact,
the mass of the object itself is of

148
00:13:07.879 --> 00:13:13.519
less important. For example, you
know, if you're in Earth orbit,

149
00:13:15.240 --> 00:13:18.879
if you're at four hundred kilometers,
you've got to have a certain velocity to

150
00:13:18.919 --> 00:13:24.159
stay in orbit, whether you're a
cube SAT or whether you are the International

151
00:13:24.200 --> 00:13:28.240
Space Station much more massive than a
cube SAT. So it's all about the

152
00:13:28.559 --> 00:13:35.600
orbital velocity and the distance from the
Sun. That's what dictates basically where planets

153
00:13:35.840 --> 00:13:41.399
stay. They've obviously formed there at
those distances. We think the gas giants

154
00:13:41.399 --> 00:13:46.320
are gas giants because they're beyond the
frost line, so that they grew big

155
00:13:46.360 --> 00:13:52.360
as they accumulated ice and that made
them, you know, give them the

156
00:13:52.360 --> 00:13:58.279
possibility of accumulating still more material to
gas around them. I hope that answers

157
00:13:58.320 --> 00:14:03.320
the question beyond Bianna. Thanks very
much and so good to hear from you,

158
00:14:03.399 --> 00:14:07.919
and hope all is well in Florence. This is Space Nuts Andrew Dunkley

159
00:14:07.919 --> 00:14:13.120
with Professor Fred Watson Space Buds.
Now, Fred, we've got a text

160
00:14:13.240 --> 00:14:18.759
question that's come in from Brady.
Hello from the great state of Florida,

161
00:14:18.919 --> 00:14:22.120
with a great view of all the
launches here, are you lucky Duck?

162
00:14:22.879 --> 00:14:28.600
I was wondering if a moon could
have a moon also, would that be

163
00:14:28.679 --> 00:14:35.159
called a moon? Moon? Love
listing to you all every week, Brady.

164
00:14:35.200 --> 00:14:37.399
Thanks Brady, very jealous of where
you are. I'd love to be

165
00:14:37.440 --> 00:14:43.159
able to sit and watch a few
launches from Florida. What a mesmerizing place.

166
00:14:43.240 --> 00:14:48.720
I've been lucky enough to visit there
and found it all very extraordinary.

167
00:14:48.480 --> 00:14:52.399
Could a moon have a moon?
Fred? Just a footnote to that.

168
00:14:52.440 --> 00:14:56.480
I'll be there in about three weeks, and yes you will. By the

169
00:14:56.480 --> 00:15:03.759
time this episode's out of me,
you're probably already. But moon of the

170
00:15:03.879 --> 00:15:09.159
moon, Yes, such an object
will be defined as a sub satellite,

171
00:15:11.039 --> 00:15:16.360
so satellites are moons. It satellites
the technical term that we use nowadays.

172
00:15:16.399 --> 00:15:20.240
People think of them as artificial satellites, but actually the word means the satellite

173
00:15:20.600 --> 00:15:24.639
of a planet, something going around
a planet. A sub satellite will be

174
00:15:24.960 --> 00:15:33.559
something going around a satellite, And
the the answer is yes, it could.

175
00:15:33.840 --> 00:15:39.039
Theoretically, you could have a sub
satellite, you could have a moon

176
00:15:39.039 --> 00:15:48.679
of a moon, but the odds
are that they're quite rare. And the

177
00:15:48.720 --> 00:15:52.600
reason for that is that we know
of none in the Solar System. Of

178
00:15:52.639 --> 00:15:54.960
all the two or three hundred moons
that we know in the Solar System,

179
00:15:54.960 --> 00:16:00.720
I can't remember the exact number now, none of them have a sub satellite.

180
00:16:00.799 --> 00:16:11.840
None of them have a moon.
So that is probably because theory suggests

181
00:16:11.000 --> 00:16:15.519
that, and this would depend on
what the planet was like the planet that

182
00:16:15.559 --> 00:16:22.600
these things are going around. It's
the tidal effects of the planet that are

183
00:16:22.240 --> 00:16:29.679
probably what would disturb or what has
disturbed any possible sub satellites in the Solar

184
00:16:29.720 --> 00:16:33.480
System. So what I'm saying is
in the Solar System at least, the

185
00:16:33.519 --> 00:16:38.399
reason why we don't find moons of
moons is because of the gravitational pull of

186
00:16:38.440 --> 00:16:44.360
the planets themselves. These actually make
the would make it unstable, so you

187
00:16:44.559 --> 00:16:47.919
lose the moon of the moon.
The moon itself might stay there, but

188
00:16:48.080 --> 00:16:52.720
this other moon going around it might
be too unstable. And it's all of

189
00:16:52.759 --> 00:16:56.559
it just because of the tidal effects, that's the gravitational pulling effects of the

190
00:16:56.600 --> 00:17:00.960
planet itself. But that might not
always be the case. It's the case

191
00:17:00.960 --> 00:17:04.920
in the Solar System, but it
might not always be the case. And

192
00:17:06.119 --> 00:17:15.839
there is at least one basically one
planet, which is Kepler sixteen twenty five

193
00:17:15.960 --> 00:17:23.319
B, which which could in theory
have a satellite, and in theory could

194
00:17:23.400 --> 00:17:29.160
have a sub satellite. So that's
just because of the gravitational you know,

195
00:17:29.319 --> 00:17:33.359
distribution between the parent star which is
Kepler one six two five and the planet

196
00:17:33.559 --> 00:17:38.759
Kepler one six two five B.
That's that's one suggestion. But as far

197
00:17:38.759 --> 00:17:42.920
as we know, there are any
in the Solar system, Okay, So

198
00:17:44.799 --> 00:17:48.799
for it to happen, the circumstances
have to be exactly right, exactly that's

199
00:17:48.880 --> 00:17:52.039
right, to be a bit special. The answer to your question for two

200
00:17:52.079 --> 00:17:55.279
hundred and ninety three moons in the
Solar system, Oh there you go,

201
00:17:55.799 --> 00:17:59.400
two ninety three. Thank you,
at last count, At last count,

202
00:18:00.599 --> 00:18:03.839
thanks Brady. I like your name
better moon Moon. That works for the

203
00:18:03.920 --> 00:18:07.880
moon. Yes, this is space
Nuts. Andrew Dunkley here with Professor Fred

204
00:18:07.920 --> 00:18:23.279
Watson. Three four Space Nuts.
Now we've got a question from Scott Hey.

205
00:18:23.359 --> 00:18:29.599
This has Scott from Oregon. I
recently became aware of HD eleven zero

206
00:18:29.720 --> 00:18:37.319
zero six seven system because apparently it
has six exo planets that are orbiting in

207
00:18:37.480 --> 00:18:44.079
like a I I think, perfect
mathematical arrangement or something. But my real

208
00:18:44.160 --> 00:18:48.440
question is really about like it's a
part of a triple star system, and

209
00:18:48.480 --> 00:18:56.160
at least according to the information I
found, the companion planet is it's actually

210
00:18:56.160 --> 00:19:04.240
a companion binary star system is thirteen
thousand, four undred astronomical units from the

211
00:19:04.319 --> 00:19:07.799
primary star. And I'm just kind
of curious, is why when something is

212
00:19:07.839 --> 00:19:12.440
that paraway, is it kind of
considered still like a triple star syst.

213
00:19:14.079 --> 00:19:18.599
I just assumed the you know,
we're I mean, that seems like a

214
00:19:18.640 --> 00:19:22.359
really far distance for them to still
be kind of considered together. So I'm

215
00:19:22.359 --> 00:19:26.599
just go curious start how they caind
of categorize these things. Thanks, thank

216
00:19:26.599 --> 00:19:30.799
you, Scott. That is a
great question a triple star system, but

217
00:19:32.079 --> 00:19:37.440
he's questioning distance and whether or not. It could actually be that. Yeah,

218
00:19:37.480 --> 00:19:41.839
that's how far is too far for
a binary slash triple star system.

219
00:19:44.480 --> 00:19:49.039
That's look at again. This is
a great question, and it's it's really

220
00:19:49.720 --> 00:20:00.640
all about gravitational what we call gravitational
binding. So that's star HD sixty seven

221
00:20:02.480 --> 00:20:07.759
is gravitationally bound to this spectroscopic binary
system, which is called HD eleven zero

222
00:20:07.799 --> 00:20:17.599
one zero six. Now you know
that eleven double zero sixty seven is interesting

223
00:20:17.640 --> 00:20:22.240
because of these six planets which are
in a lovely orbital resonance with each other.

224
00:20:23.119 --> 00:20:29.640
It's at a distance of one hundred
and five light years. But Scott's

225
00:20:29.680 --> 00:20:33.079
question isn't really about the planet.
There's the star and its planets. It's

226
00:20:33.119 --> 00:20:40.000
about this companion binary system. What
do we mean by a spectroscopic binary system?

227
00:20:40.319 --> 00:20:44.319
A binary system is two stars orbiting
around the common center of gravity,

228
00:20:44.400 --> 00:20:48.880
usually called the Barry center. If
it's spectroscopic, it means we can't see

229
00:20:48.880 --> 00:20:52.160
them as two separate stars. We
can see them as a single star in

230
00:20:52.200 --> 00:20:59.519
any telescope. But we know it's
two stars because the spectroscope of the spectrograph

231
00:21:00.039 --> 00:21:07.000
reveals by the Doppler effect that there
are two sets of barcodes which are moving

232
00:21:07.119 --> 00:21:11.960
relative to one another as the stars
orbits each other. So it's by using

233
00:21:11.000 --> 00:21:15.359
the spectroscope that we know that there
is a pair of stars there rather than

234
00:21:15.400 --> 00:21:22.960
just a single one, whereas HG
double one double zero sixty seven itself is

235
00:21:23.000 --> 00:21:30.519
said to be part of this as
a triple star system. So Scott quotes,

236
00:21:30.519 --> 00:21:33.599
and I haven't actually verified this,
but I'm sure he's right. Thirteen

237
00:21:34.039 --> 00:21:41.799
four hundred astronomical units of separation between
them. Now, that's about a quarter

238
00:21:42.240 --> 00:21:49.000
of a light year. A light
year is about sixty three three hundred astronomical

239
00:21:49.160 --> 00:21:52.960
units, or what's an astronomical unit
distance from the Earth to the Sun one

240
00:21:53.039 --> 00:22:00.720
hundred and fifty million kilometers. So
an astronomical unit is a unit we use

241
00:22:00.079 --> 00:22:03.480
within the Solar system. Tend to
use light years beyond the Solar system,

242
00:22:04.200 --> 00:22:07.359
but for a triple star system,
that is quite a long way off.

243
00:22:07.400 --> 00:22:11.759
Thirteen thousand and four audio astronomical units. As I said, it's roughly a

244
00:22:11.839 --> 00:22:15.839
quarter of a light year. I'm
going to throw in a coincidence here,

245
00:22:15.079 --> 00:22:22.240
Andrew that you probably don't know about, but the number of astronomical units in

246
00:22:22.279 --> 00:22:25.440
a light year is, as I
said, about sixty three thousand, three

247
00:22:25.519 --> 00:22:29.559
hundred is very very similar to the
number of inches in a mile, which

248
00:22:29.559 --> 00:22:33.200
is about sixty three thousand and three. Right. Wow, it's a nice

249
00:22:33.240 --> 00:22:37.079
coincidence that we can't use anymore because
we're electric here, well anyway, except

250
00:22:37.359 --> 00:22:42.359
they can use it in America they
can, yes, But so what means

251
00:22:42.480 --> 00:22:49.000
what defines it as these two are
the binary and the star itself HD eleven

252
00:22:49.079 --> 00:22:55.200
zeros or A sixty seven, what
makes it a triple star system. It's

253
00:22:55.240 --> 00:23:00.000
because they are gravitationally bound. The
movement of the two relative to each other

254
00:23:00.279 --> 00:23:03.880
tell you that they are in orbits
around their common center of gravity. And

255
00:23:03.960 --> 00:23:11.440
so once again that's detected spectroscopically and
probably actually also by the Gaya astrometry spacecraft,

256
00:23:11.480 --> 00:23:15.519
which can measure the positions of stars
very very accurately. Indeed, so

257
00:23:15.079 --> 00:23:21.319
I think that is why it's termed
a triple system rather than just two stars

258
00:23:21.319 --> 00:23:23.759
that have to be near each other. It's because they've got movements that suggest

259
00:23:23.799 --> 00:23:29.039
that they're gravitationally bound to each other. They are dancing. They're dancing what

260
00:23:29.119 --> 00:23:32.279
a lot of the most book,
Yes, yeah, well a dance like

261
00:23:32.359 --> 00:23:37.640
me. One of them is going
to fall over real quick indeed, so

262
00:23:37.960 --> 00:23:44.079
there you ask God. Hopefully that
will appease you at least answer your question.

263
00:23:44.799 --> 00:23:47.200
We've got one without notice, and
I know you love those Fred.

264
00:23:48.640 --> 00:23:56.799
This comes from a Facebook user listener, Dean A. Fellas. A question

265
00:23:56.920 --> 00:24:02.240
for you, how does Hubble maintain
a steady image of targets while in orbit?

266
00:24:03.119 --> 00:24:10.720
It's stabilized, and what stabilizes it
are gyroscopes, which are an absolutely

267
00:24:10.839 --> 00:24:17.519
vital part of the mechanism that operates
Hubble, and in fact it's why Hubble's

268
00:24:17.559 --> 00:24:25.799
lifetime will eventually be limited because the
gyroscopes did fail. I think they need

269
00:24:25.839 --> 00:24:27.880
three. I think they can just
about manage with two, but they need

270
00:24:27.920 --> 00:24:36.119
three to work properly. Back in
the day, two thousand, probably two

271
00:24:36.200 --> 00:24:45.000
thousand and eleven ish thereabouts, trying
to think when the yeah, I think

272
00:24:45.000 --> 00:24:51.920
twenty eleven was when the last Hubble
mission, Hubble repair mission went up,

273
00:24:51.960 --> 00:24:55.960
and it was to repair or to
replace gyroscopes. That was in the last

274
00:24:56.039 --> 00:25:00.279
year or so of the Space Shuttle, because the Space Shuttle was the only

275
00:25:00.359 --> 00:25:04.160
vehicle then available that could reach the
orbit of the of the Hubble Space Station

276
00:25:04.519 --> 00:25:10.400
sorry Hubble space Telescope at six hundred
kilometers, so it's gyroscopes which have failed.

277
00:25:11.160 --> 00:25:14.759
They're still working pretty well as far
as I know, but maybe again

278
00:25:14.759 --> 00:25:17.440
they will fail and that will bring
the mission to an end, because you

279
00:25:17.440 --> 00:25:22.240
want me to point the telescope,
Yes, exactly, And that was twenty

280
00:25:22.279 --> 00:25:27.039
twenty three, I think when Yeah, No, it was a while further

281
00:25:27.720 --> 00:25:32.079
further back than that. I remember
us talking about those gyro failures. Wasn't

282
00:25:32.079 --> 00:25:37.160
that long ago? There might have
been other ones, could have been been

283
00:25:37.240 --> 00:25:40.279
since that mission. I mean,
Hubble's been up there at it for a

284
00:25:40.359 --> 00:25:45.039
very long time. Things don't last
for four years. Yeah, it's incredible,

285
00:25:45.119 --> 00:25:49.799
isn't it. Of course there are
going to be new telescopes like James

286
00:25:49.799 --> 00:25:53.640
web in Action and the new one
that he says set up, and of

287
00:25:53.680 --> 00:25:59.319
course we talked about one Lancy Grace
Roman Times, yeah, which is also

288
00:25:59.359 --> 00:26:02.519
going to be launched in a few
years. So plenty more going up there

289
00:26:02.559 --> 00:26:07.039
to continue the work. But yeah, thanks for the question. Lovely to

290
00:26:07.079 --> 00:26:10.599
hear from your dean, And if
you do have questions for us, please

291
00:26:10.839 --> 00:26:15.559
send them to us via our website, space nuts podcast dot comspacenuts dot io

292
00:26:15.799 --> 00:26:19.799
and send it to us simply by
clicking on the relative button you can click

293
00:26:19.839 --> 00:26:23.599
on the AMA tab where you can
send us audio or text questions, or

294
00:26:23.640 --> 00:26:26.640
on the right hand side this this
weird green button that says send us your

295
00:26:26.680 --> 00:26:32.599
questions. When you hover over it, it turns purple. Yeah. I

296
00:26:32.599 --> 00:26:34.480
don't know, but you can send
us your question there as long as you've

297
00:26:34.519 --> 00:26:41.440
got a device with a microphone.
All good, and don't forget to tell

298
00:26:41.519 --> 00:26:44.160
us who you are and where you're
from, and we'll do our best to

299
00:26:44.359 --> 00:26:48.359
give you an answer. Fred.
That's the end of another episode. Thank

300
00:26:48.400 --> 00:26:52.200
you, sir, pleasure, good
questions and great stuff. Keep them coming

301
00:26:52.200 --> 00:26:56.519
in, folks. It's great to
Yeah, all right, Fred, catching

302
00:26:56.599 --> 00:27:02.079
next week. Thank you, Professor
Fred Watson Astrong at Large. And thanks

303
00:27:02.119 --> 00:27:04.920
to Hue in the studio who were
funneled through a couple of late questions that

304
00:27:06.000 --> 00:27:08.640
we managed to well. We put
one on the back burner and we tackled

305
00:27:08.640 --> 00:27:11.559
the other. And from me Andrew
Unkley, thanks for joining us. Catch

306
00:27:11.559 --> 00:27:17.119
you on the very next episode of
Space Nuts. Bye bye. You'll be

307
00:27:17.279 --> 00:27:25.039
listening to the Space Nuts podcast available
at Apple Podcasts, Spotify, iHeartRadio,

308
00:27:25.400 --> 00:27:29.839
or your favorite podcast player. You
can also stream on demand at bites dot

309
00:27:29.839 --> 00:27:36.279
com. This has been another quality
podcast production from sites dot com.