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Cosmic Chronicles: UFOs, Galactic Archaeology & the Mystery of the Zombie Satellite · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
Heidi Campo: Welcome back to another episode of Space
0:03
Nut. I am your host for this season,
0:05
Heidi Campo. And joining us is
0:08
professor Fred Watson, astronomer at large.
0:11
Generic: 15 seconds. Guidance is internal.
0:14
10, 9. Ignition
0:17
sequence. Star space nuts. 5, 4, 3,
0:20
2. 1. 2, 3, 4, 5, 5, 4,
0:22
3, 2, 1. Space nuts.
0:25
Astronauts report. It feels good.
0:28
Heidi Campo: Fred, did you know that today
0:31
is world UFO Day?
0:33
Professor Fred Watson: Oh, um, no, I didn't.
0:37
I've got a feeling I saw something about that
0:39
and then, um, it moved on.
0:42
Heidi Campo: Um, how do you know? So I'm trying to fill in
0:45
for our normal host, Andrew Dunkley. And
0:48
he loves his dad joke, so I figured I'd need
0:50
to bump up the dad joke. So, Fred, how do you
0:53
know if you are talking to an
0:55
extraterrestrial?
0:58
Professor Fred Watson: Um, because their lips
1:01
don't move.
1:03
Heidi Campo: Well, you need to ask them probing questions.
1:08
Professor Fred Watson: I love that. Yes, I like that very much.
1:11
Heidi Campo: It was not original. My Alex Zaharov-Reutt
1:13
told me that whole spiel this morning.
1:15
I thought that was too good not to share with
1:17
you guys.
1:17
Professor Fred Watson: Yeah, it's a good one. Um,
1:20
a very probing answer as well.
1:24
Heidi Campo: Well, how are you today? Are you excited?
1:26
Professor Fred Watson: Um, well, look, I go through my life in a
1:29
state of permanent excitement. Um, Heidi.
1:32
And who, who wouldn't be? When we're mixed up
1:34
with all this fabulous news coming from
1:36
space. Astronomy, physics, biology,
1:39
it's. We're being bombarded by all these
1:41
marvelous discoveries. And, um, that, uh,
1:43
certainly for me is very exciting.
1:46
And, um, the annoying thing for me
1:49
is that I'm at the sort of end of my
1:52
career. That means that a lot
1:55
of the things I want to know the answers to
1:59
may be beyond my horizon.
2:03
And that's really, uh, irritating. Um,
2:06
but that's okay. I mean, I'm thinking of
2:08
things like. And this might be beyond many
2:10
people's horizon. For example, um, the plans
2:13
to build a new, uh, future circular
2:16
collider, as it's called, uh, by the
2:19
cern. The, um, nuclear research
2:22
center, uh, on the French Swiss border.
2:24
They're planning this machine which will
2:26
switch on in 2070.
2:29
And, um, you know, we're going to discover
2:32
wonderful things from it. 2070 is above
2:35
many people, beyond many people's horizon.
2:38
Certainly beyond mine.
2:40
Heidi Campo: Yeah, there's some existentialism in the
2:42
first three minutes of the episode today.
2:44
Professor Fred Watson: Yeah, there you go. So. Yes, that's right.
2:46
Um, um, so for all you
2:49
space nuts out there, don't worry, you'll
2:51
all. You'll all hear the answers to many of
2:54
the questions that you want to know about,
2:56
like dark matter, dark energy, is
2:59
there life elsewhere? All these Questions are
3:01
probably within your horizon, but maybe not
3:03
mine.
3:05
Heidi Campo: Maybe one, uh, of these days, I know we had,
3:07
uh, some, some kids, um, come in with some
3:10
questions on some of the Q and A episodes.
3:12
Maybe one day, when they're the hosts, these
3:14
things will be discovered.
3:16
Professor Fred Watson: Exactly. That's right. That's the thing to
3:18
look forward to. It's not, it's, it's
3:20
existential stuff, but it's good new stuff as
3:23
well. Because, you know, science is one of
3:25
those things that just keeps on moving and we
3:27
keep on learning new things and who knows
3:29
what we might discover that will transform
3:31
our understanding, uh, of the universe. I
3:34
think that's the end of the show, isn't it
3:35
today, Heidi? I think we've covered
3:37
everything there.
3:39
Heidi Campo: Oh, well, today is a great one and here's my
3:41
segue.
3:41
We're going to just jump right into
3:42
introducing all of our articles. We have
3:45
history, we have mystery, and
3:48
we have discovery. We are really
3:51
covering the full spectrum of
3:53
space science today. And our history
3:56
article today is touching on
3:59
a, basically a James Webb
4:02
discovery of how the
4:05
Milky Way, um, was kind
4:08
of formed. Is that about right, Fred?
4:10
Professor Fred Watson: Yep, right on the money there, Heidi. Uh,
4:13
and it's, this is actually a topic
4:16
that's close to my heart because
4:18
I've been involved with research very like
4:21
this. Um, so
4:23
what uh, the Webb Telescope is doing is
4:26
looking at what we call cosmic archaeology,
4:29
which uh, is trying to understand basically
4:33
the evolution of galaxies, the detailed
4:36
evolution of galaxies. Uh, but it relates
4:39
to um, something that has been very
4:42
actively pursued in the last 20 years
4:44
or so. A topic that we call galactic
4:47
archaeology. And that's understanding how
4:50
our own galaxy came to be put together.
4:53
Uh, and uh, that topic has
4:56
led to some quite significant discoveries.
4:58
The people I've worked with have made some of
4:59
these discoveries. Uh, uh, we've
5:02
been working on a project called galah. Galah
5:05
is, uh, an Australian bird, a very
5:08
well known, um, species of Australian bird.
5:11
G A L A H. Galah stands for
5:14
galactic archeology with Hermes. Hermes
5:17
being the instrument that we used to do this.
5:20
Uh, so I was um, very much on the
5:22
observational side of this project, but
5:24
worked with people who discovered some of the
5:26
fundamental properties of our galaxy. And
5:29
that relates directly to the story that we've
5:32
got coming from the James Webb Telescope.
5:34
Because one of the discoveries that my
5:35
colleagues made was that the disk of our
5:38
galaxy, uh, ah, and remember our
5:41
galaxy is this flattened spiral of stars and
5:44
gas and dust and dark matter, um, which
5:47
ah, basically is disk shaped. And we
5:50
see that when we See the Milky Way, we're
5:51
looking the thickness of the disk. We've
5:53
known for a long time, more than 100 years,
5:56
that there is another component to the
5:58
galaxy, and that's what we call the halo. Uh,
6:01
this is a spherical region of,
6:03
um, stars and what we
6:06
call globular clusters. These, uh,
6:09
very dense clusters of stars that surrounds
6:11
the disk of the galaxy. But the people I
6:14
worked with made a discovery that there is
6:16
another component, and that is that the disk
6:19
is not just a single item. It has
6:22
two parts to it, which maybe not
6:24
surprisingly, are called the thin disk and
6:27
the thick disk, um, because one's
6:30
thin and one's thick, and they're two
6:32
different sort of populations, uh, of stars.
6:35
So the thin disk really is what we see when
6:37
we look at the Milky Way. But there is a
6:40
more rarefied population of stars that make
6:42
up a thicker disk. And they've got different
6:45
dynamical characteristics. That's to say they
6:47
move in different ways. So that's the
6:50
segue to this story from the James Webb
6:52
Telescope, because people are now looking at,
6:54
uh, other galaxies beyond our own to see
6:57
if the thin and thick disks can be detected.
7:01
Uh, I mean, it's taken us, you know,
7:03
centuries, I guess, to work out that the disk
7:06
of our galaxy was in two components.
7:10
Let's now move outwards and look at other
7:13
galaxies to see whether they are the same
7:16
and to see how that informs our own
7:18
understanding of the evol of our own
7:21
galaxy. So, um, the team of astronomers,
7:24
uh, one of whom was based here in Australia,
7:26
I'm glad to say, and that's actually the team
7:28
leader, uh, that's, um, again carrying on
7:31
this tradition of, uh, Australian involvement
7:34
with the idea of thin and thick disks. So
7:36
they've looked at, um, 100 galaxies,
7:39
uh, up to 11 billion
7:42
years ago. So we're talking now about very
7:45
distant galaxies, uh, in the early universe.
7:48
Uh, and basically look to see how
7:51
the thin and thick disks, uh,
7:55
appear in those galaxies. Um,
7:58
in particular, uh, the question they want to
8:01
ask is when you've got a galaxy forming and
8:04
evolving, uh,
8:07
what is the point at which that
8:09
structure that we have in our own galaxy,
8:11
that dual disk structure, what's the point
8:14
at which that forms? And so what they've done
8:17
is they've chosen galaxies. And this
8:20
is kind of what you'd expect them to do.
8:22
They've chosen galaxies that we see edge on.
8:25
Um, and so that means that you're looking
8:28
directly at the disk itself. It's
8:31
edge onto you, uh, rather than face on.
8:34
And that means that you've got a good chance
8:36
of seeing the stars in the thick disk and the
8:38
thin disk separated. And indeed
8:41
that's what they have found. Um, and
8:44
this is actually world leading research. It's
8:47
the first time that astronomers have
8:49
studied um, these two
8:52
populations of stars in galaxies in the
8:55
early universe. So the bottom line
8:58
uh, of this story is that uh,
9:01
it looks as though from the observations that
9:03
have now been made of these hundred galaxies,
9:06
uh, it looks as though the thick disk
9:08
forms first. So what you get is
9:11
initially is the thick disk, uh, and then the
9:14
thin disk within it forms later on.
9:18
Uh, and so that's new knowledge.
9:20
That's something that we, we didn't um, you
9:23
know, we didn't appreciate before. It's
9:26
actually a very, very fine piece of research
9:29
that feeds directly into our understanding of
9:32
our own galaxy. Taking information from
9:34
distant galaxies, uh, in the early universe.
9:37
I was full of admiration for it.
9:40
Heidi Campo: That's, that's amazing. So why do they think
9:42
that is with the, with the thicker disc
9:45
that they think is the more mature one, Are
9:47
they seeing the, the clusters
9:50
in a more um, un.
9:52
Uniform spin then? So it seems like as,
9:55
as they, as the, I don't know what the,
9:58
as the discs get more mature, the
10:01
clusters get more sporadic.
10:04
Professor Fred Watson: Yeah, that's right. It's the stars themselves
10:07
that um, m. Define how these disks
10:10
appear. And I think your point is right
10:12
though because what we call the
10:15
kinematics of the thick disk in our own
10:17
galaxy, that's the way stars move in it. It's
10:18
a lot more um, disorganized than
10:22
the kinematics of the thin disk. The thin
10:24
disk has very, very well behaved star motions
10:27
in it. For example, the sun is in orbit
10:29
around the galactic center. It's a very neat
10:32
and tidy orbit. Takes about
10:35
uh, 200 million years to go around once. Uh,
10:38
so, uh, and all the stars in our
10:41
neighborhood are doing the same sort of
10:42
thing. But the thin disk is less well
10:45
organized. It's got much higher uh,
10:48
velocities outside the plane of the disk.
10:50
So there's a sort of vertical component of
10:53
the velocity of stars in the thick disks as
10:55
well. And so you're right. It looks as though
10:57
that older disk, um,
11:00
uh, the thick disk being
11:03
the first thing to form, uh, stars in
11:05
it, eventually collapse towards a thin
11:08
disk, um, uh,
11:11
in response to the galactic pull of the
11:14
whole galaxy. And perhaps uh, an analog with
11:17
this is the rings of Saturn, which
11:20
are a uh, very, very thin disk of
11:22
material. Um, you probably know that rings of
11:25
Saturn are about 250,000 kilometers in
11:27
diameter and less than 100 meters thick.
11:30
100 meters thick. So it's
11:33
a blade of material in space. Um,
11:36
and that is because of the gravitational
11:39
forces that act on it from the planet Saturn
11:41
itself. And so it looks as though something
11:44
perhaps analogous to that happens in our
11:46
galaxy that you eventually get the,
11:49
um, stars in the disk shepherded into this
11:51
quite thin region, uh, leaving behind
11:54
remnants of perhaps an earlier phase, which
11:56
is what we see as the thick disk.
11:59
Heidi Campo: So the opposite of most people. When we age,
12:01
we tend to get, uh, a little bit thicker.
12:05
Professor Fred Watson: Nicely done. Very nicely done.
12:07
Heidi Campo: Especially around the middle.
12:09
Professor Fred Watson: Well, yes, that's right.
12:11
Heidi Campo: Well, you know, we can't all be as beautiful
12:13
as, um, Saturn with its
12:16
beautiful, uh, discs.
12:22
Space nuts.
12:23
Um, but this next story
12:27
is a mystery and that's kind of fun and
12:29
exciting. So, you know, we just talked about
12:32
our galaxy forming, but this next one is
12:36
a little bit less straightforward than what
12:39
you just explained. And I'm really excited to
12:41
hear what you have to say because you have
12:43
such a great way of taking something
12:44
complicated and making it make sense to us.
12:47
But tell us about this. Ah, the surprise in
12:50
the desert.
12:51
Professor Fred Watson: Yeah, so. And it's, um. Again, this is
12:54
relatively close to home. This is research
12:56
that's being done here in Australia. Uh, and
12:59
I think we've talked about it before, Heidi.
13:01
Um, uh, a facility called the Square
13:04
Kilometer Array Observatory.
13:07
Skao, uh, uh, is,
13:09
um, an international project. I think it's
13:12
got seven, maybe eight nations involved in it
13:15
now, uh, uh, with
13:18
facilities in Australia, in South
13:21
Africa and in the UK and the UK is just
13:24
where the headquarters is. So our telescopes
13:26
here in Australia. Um, there is. The
13:29
Square Kilometer Array itself is being
13:32
built. It will probably see fully, uh,
13:35
first light, first radio signals,
13:38
uh, in, um, something like five.
13:41
Sorry, three to four years. Uh, but there is
13:43
what's called a pathfinder, uh, um, and it
13:46
rejoices in this marvelous name of ascap,
13:49
uh, the Australian Square Kilometer Array
13:51
Pathfinder. And that's, uh,
13:54
used, um, very effectively
13:57
for, um, finding many
14:00
different sorts of objects in space. It has
14:02
about 30 dishes, uh, in the
14:05
Western Desert of Australia. Um, and in
14:08
particular it's been really good, ah, finding
14:11
these things called fast radio bursts,
14:15
um, which my colleagues in the
14:17
radio broadcasting business tell me should be
14:19
pronounced fast radio burst because they're
14:22
very fast.
14:23
Heidi Campo: I don't know why that was so.
14:24
Professor Fred Watson: Funny to me, anyway. Well,
14:27
it's a bad name because really they're short
14:29
radio bursts. Excuse me. They're,
14:32
um, something like a millisecond long. And
14:34
they're flashes of radio radiation
14:38
which have now been recorded, uh, for
14:40
something like a couple of decades. And so
14:42
they've been very well studied. Um, and,
14:45
um, we think they come from what are called
14:48
magnetars. Uh, these are, uh,
14:50
neutron stars, highly collapsed.
14:53
Excuse me, highly collapsed stars which have
14:56
very strong magnetic fields. And you get
14:58
flares on these stars. Um,
15:01
that's what we think fast radio bursts are
15:03
caused by. But in making those
15:06
measurements, this team of astronomers
15:09
actually came across something that was a
15:12
burst of radiation, uh, very bright,
15:14
a bit like a fast radio burst. But
15:17
rather than being, uh, you know, a
15:20
thousandth of a second long or thereabouts,
15:23
this was a few billionths of a
15:26
second long. It was incredibly
15:28
brief. Uh, so it actually, the
15:31
pulse that they measured lasted for 30Ns,
15:34
30 billionths of a second. And
15:37
that's a mystery. Um, we have never seen
15:40
anything like this before. So they were
15:42
puzzled. Uh, it took them a year to
15:45
try and work out what it is that we think
15:48
we're seeing. Uh, and
15:51
first of all, they had some hints, um,
15:54
that it might be quite close by. Because
15:57
in the radio telescope world, there's a
16:00
phenomenon called dispersion. If you have a
16:01
pulse of radiation, um, the higher
16:04
frequencies get to you before the lower
16:06
frequencies. That's the phenomenon of
16:08
dispersion. And so, uh, that,
16:12
um, uh, is something that you
16:14
look for as a kind of indicator of distance.
16:17
Now, this particular 10, uh, sorry, 30
16:21
nanosecond pulse didn't show
16:24
that dispersion phenomenon. And that tells
16:27
you that it's coming from relatively
16:29
nearby rather than deep in the universe,
16:32
unlike the other things. And in fact, they
16:35
could also see that it was out of focus.
16:38
It had blurriness in the image. And so
16:41
that let them put a, an estimate of distance
16:44
on it. And rather than it being several
16:46
billion light years away, like most of the
16:48
fast radio bursts are, the distance they got
16:51
for this was 4,500 kilometers.
16:54
Uh, what's that? That's about 3,000 miles.
16:57
Um, so that's, uh, rather
16:59
nearby, which tells you, uh, it is
17:02
probably, uh, coming from a satellite. And so
17:05
they worked out from the direction that
17:07
they'd seen it in, uh, what
17:10
satellite it might be. And they identified
17:12
one. And it's a satellite called
17:15
Relay 2 that was launched
17:17
in 1964, and it was one
17:20
of the first telecommunications
17:23
satellites. Now, by 1967, the
17:26
whole thing had switched off. It was just a
17:28
defunct piece of space junk. Um, so this
17:31
satellite, Relay 2, has not done
17:33
anything for, um, well, 60
17:36
years, nearly 60 years.
17:39
Uh, and so it's a real puzzle
17:42
as to why a dead satellite
17:45
should suddenly produce a
17:48
flash of radiation that's a billionth of a
17:51
second or 30 billionths of a second long, um,
17:54
and be incredibly bright. And I think the
17:57
only thing that the team has been able to
18:00
come up with, uh, and they're saying they
18:02
think this is the most likely cause, uh,
18:05
is an electrostatic discharge.
18:08
Um, and we're all familiar with those. When
18:11
you've got very dry weather, uh, sometimes
18:13
your clothes, as you take them off, if you've
18:16
got synthetic fabrics in your clothes,
18:19
they rub against your skin, they cause a
18:21
buildup of static electricity, and you get a
18:24
little spark once in a while. You can
18:26
actually see those. If you're in a dark room,
18:28
take. Take your jacket off, your shirt off,
18:30
and you suddenly see flashes all around you.
18:32
Heidi Campo: Here's a. Here's a cute little story about
18:34
static electricity. Every morning my dog. My
18:37
dog sleeps in the bed with me. And every
18:39
morning he sleeps down by my feet. Every
18:40
morning he kind of scoots slowly across the
18:43
bed. And he doesn't understand physics.
18:46
He doesn't understand that it's the slow
18:49
scoot towards me that's building up that
18:51
static electricity. And he, he goes and he
18:54
gives you a little kiss on the cheek every
18:55
morning. And he always gets that shock right
18:57
on his nose. And so he's developed the ha.
19:00
Of scooting slower and slower.
19:03
The poor little guy just keeps building up
19:05
more static electricity,
19:07
everybody.
19:09
So I try and touch him on his shoulder or
19:11
something before he gets to me. So it doesn't
19:12
get him on his nose. But, yeah, that's, uh,
19:14
that's a. So they're calling us the zombie.
19:17
Zombie craft. And it was a United States.
19:21
Professor Fred Watson: Uh, it was satellite. Yeah, that's
19:23
right. And so, um, the,
19:27
the. Basically the. The
19:30
thing they think is the most likely is one of
19:32
these, Ah, an electrostatic
19:34
discharge just like your dog's nose, um,
19:38
uh, but causing a flash of radio radiation.
19:40
But they say the problem at that, uh, with
19:43
that idea is that usually electrostatic
19:45
discharges relative to this one are quite
19:48
slow. They last thousands of times longer
19:50
than the 30 nanoseconds of this signal.
19:53
Um, so they postulate a second
19:57
hypothesis, which is a strike by a
20:00
micrometeoroid, a tiny piece of something.
20:02
Generic: Wow.
20:03
Professor Fred Watson: Um, which, uh, could produce
20:06
a flash of radio waves, but they
20:09
say that's got very low probability. So the
20:12
bottom line is we don't actually know, um,
20:15
that, uh, we simply don't know what this, you
20:17
know, what this, uh, signal Is
20:20
maybe, uh, we will find
20:23
a few more insights. But
20:26
um, that's uh, the, the story
20:29
from this team that's hit the news. Even
20:30
though they're doing fabulous work on fast
20:33
radio bursts. The thing that hits the
20:34
headlines is the mystery, the mystery
20:37
signal.
20:38
Heidi Campo: It is quite the mystery. And that, that was
20:41
a, that is an interesting one. I'm going to
20:44
be scratching my head about that for a little
20:45
while.
20:49
Professor Fred Watson: 0G.
20:50
Generic: And I feel fine.
20:51
Heidi Campo: Space nuts.
20:52
I'm glad that, um, our last story gives us a
20:55
little bit of closure with a new
20:58
alloy that was discovered. A
21:01
new alloy, um,
21:04
it's needed for an exoplanet discovery.
21:07
Professor Fred Watson: This is a really. Yeah, it's a really
21:09
interesting story because, um, you know, why
21:12
should something, uh, that seems to be
21:14
metallurgy find its way into space
21:17
and astronomy news headlines? Uh,
21:20
uh, and the answer is that it's got
21:22
um, a definite uh,
21:25
application in our, uh, hunt for
21:28
exoplanets for planets around other stars.
21:30
And not just hunting for them, but to try and
21:32
characterize them, to try and learn more
21:34
about them. Um, so the
21:37
curious thing about this alloy, uh,
21:40
is that it has a negative
21:43
coefficient of thermal expansion. Uh,
21:46
and so what that means is, uh, as we know,
21:49
when things get hot, they tend to get bigger.
21:51
It's just like when they age. Uh,
21:54
so, um, a piece of metal, uh, if you
21:57
heat it up, it gets bigger. And the rate
22:00
at which it gets bigger with temperature is
22:02
something we call the expansion coefficient,
22:04
the thermal expansion coefficients. Basic,
22:06
basic physics. Um, there are a
22:09
few materials and one of them
22:12
is very well known to astronomers. Uh, a
22:15
few materials that don't expand or contract
22:18
with temperature, they don't do anything. Uh,
22:21
and uh, one of them is um, a glass
22:24
ceramic material which was developed in the
22:26
1970s. There are two versions of it. One
22:29
is called Servet, uh, that was made by Owens,
22:32
Illinois in the United States. Uh, and the
22:35
other, um, I can't remember its name, but
22:37
it's made by the Schott Glass Company in
22:39
Europe. Uh, these are ah, effectively
22:42
what looks like a piece of brown glass,
22:45
but it's a mixture. Uh, it's got the
22:47
properties of both glass and a ceramic and it
22:49
has a zero expansion coefficient. So as the
22:52
temperature changes, if you make a telescope
22:54
mirror out of this, which has a surface
22:56
accurate to a few billionths of a meter,
23:00
uh, uh, if you make a mirror out of this, as
23:02
the temperature changes, uh, it doesn't alter
23:05
its shape. And that is why most of the
23:08
mirrors, big telescopes in the world today
23:10
are made from this material. Including the
23:12
one I used to be, uh, a astronomer in charge
23:14
of at uh, Siding Spring Observatory. But this
23:17
new material, this new alloy has the opposite
23:20
characteristic. When you heat it up, it
23:22
contracts. Uh, and that's very
23:25
much, uh. Uh, you know, it's very different
23:28
from uh, what we expect to find with
23:30
metals. But what it does is
23:33
because it's so different from normal metals.
23:37
It gives you the possibility of building
23:39
structures that have
23:42
uh, some of this new alloy, uh, in
23:45
them, uh, which will contract with
23:47
temperature. It's called Alvar Alloy 30,
23:50
by the way, to give it a name. Um,
23:53
uh, if you can combine
23:56
that with metals that have
23:59
the normal thermal expansion characteristic.
24:02
Then one can compensate for the other. And
24:04
they can essentially cancel out any
24:08
form of temperature, uh, distortion,
24:11
uh, that you might get as the temperature
24:13
changes. Your structure is built in such a
24:16
way that it doesn't change its shape because,
24:20
uh, the two different uh, coefficients cancel
24:23
out. And that's important in one
24:26
specific field which has been identified. And
24:29
this actually is appropriate for both space
24:32
telescopes and ground based telescopes. Uh,
24:35
when you're looking for, um,
24:38
for planets around other stars,
24:41
uh, what you need, uh, is
24:44
absolute stability in the instrument.
24:47
Uh, because the measurements you're trying to
24:49
make, whether they're what we call the
24:51
Doppler wobble technique, which is where the
24:54
motion of a planet around the star pulls the
24:56
star slightly one way and then the other as
24:58
it goes round. And we see the star exhibiting
25:01
that backwards and forwards motion which can
25:03
be measured. Whether it's that or whether
25:05
you're looking for a direct image of
25:08
a planet going around its parent star. All of
25:11
these need instruments that are utterly
25:13
stable over long periods of time.
25:16
Um, the way you normally compensate for this,
25:19
the way we've done this in the past. Is to
25:21
have very sensitive calibration mechanisms.
25:24
So that you can, as you take your
25:26
observations, you also take calibration
25:28
measurements that tell you whether that your
25:30
instrument is changing its shape. And that
25:32
lets you then compensate for it. But with
25:35
this new alloy, you wouldn't need to do that.
25:38
Uh, if you built your structures with normal
25:40
metal and this alloy 30. Then
25:43
you could make structures that really need
25:45
very little calibration. Uh, and that means
25:48
that you can make these high precision
25:51
measurements, uh, with the minimum of fuss.
25:54
Uh, and in particular, if you're talking
25:56
about a space telescope which is not
25:58
particularly hands on because it's up there
26:00
in orbit. Then you've got a
26:03
system that will withstand, understand the
26:04
temperature variations that you experience in
26:07
space as you go in and out of the Earth's.
26:09
Shadow, uh, and remain stable. Uh,
26:12
so I think this is quite an interesting
26:15
discovery just for its own
26:18
sake. Um, who ever would have thought of a
26:20
metal that shrinks as it gets hotter? I
26:23
certainly wouldn't. Um, and then,
26:26
you know. But it gives a really interesting
26:28
astronomical application.
26:30
Heidi Campo: Yeah, um, I was just looking here too.
26:33
It sounds very similar to another metal that
26:36
I've been researching a lot lately. Um,
26:39
and I don't know if we're talking about the
26:42
same thing, but a smart,
26:44
sorry, shape memory alloy. Are you familiar
26:47
with shape memory alloy?
26:48
Professor Fred Watson: Yeah.
26:48
Heidi Campo: So these are different then?
26:50
Professor Fred Watson: They are, yes. Uh, but the shape memory
26:52
alloys, uh, yeah, that's a really interesting
26:54
thing too because it remembers, you know, you
26:57
deflect it and it has memory of how it's been
26:59
deflected. There may be, they may be made of
27:02
similar materials. You know, some of these
27:05
alloys are quite complex chemical,
27:08
uh, um, chemical uh,
27:10
entities. They've got unusual chemical
27:12
reactions to make them. Uh, and maybe the,
27:15
you know, there might well be uh, connections
27:18
between the shape memory alloy and the
27:20
negative expansion alloy. Probably all made
27:22
by the same company somewhere down the track.
27:24
Yeah.
27:24
Heidi Campo: Well it's so interesting because it's like
27:26
the shape memory alloys are.
27:28
SMAs are also really being used a lot in some
27:31
space with um. Well they're not being used in
27:34
space yet, but there's hopes um, to have
27:37
kind ah, of smart textile spacesuit design.
27:40
And I know that MIT's been working on those
27:42
uh, spacesuit fabrics a lot, but they've kind
27:45
of hit a little bit of a roadblock because of
27:48
the amps required to make it work
27:51
is unsafe to have around humans.
27:53
It's um, the amps would be too high
27:56
and let's stop a human heart. So they're um,
27:59
they're still looking at it and maybe we're
28:02
on the cusp of having something really cool I
28:04
think of ah, Back to the Future where he, I
28:07
think is back to the future too where he has
28:09
the, the shirt and the boots that
28:12
ah, the fabric absorbs up to be the right
28:14
size for him.
28:17
Professor Fred Watson: That's, that's exactly what these things are
28:18
going to do as far as I understand it. The
28:20
shape shaped memory, uh, fabrics, um,
28:23
and uh, yeah, I didn't know that they uh,
28:26
they were currently too dangerous to wear.
28:29
Uh, that's um, that's a bit, a bit of
28:32
a um, you know, perhaps
28:35
undesirable aspect of these fabrics that if
28:38
they have currents that are too high for the
28:40
human heart to withstand. Uh, but yeah,
28:43
obviously the research is going in the right
28:44
direction with that. Yeah, it's really
28:46
interesting stuff.
28:46
Heidi Campo: And as you said, it really is exciting.
28:48
Professor Fred Watson: Yeah.
28:49
Heidi Campo: And you know, baby, I always say this, I say
28:52
this. I think maybe every episode or every
28:54
other episode, it could be the people
28:56
listening who are the ones working on this
28:58
stuff and making those breakthroughs. So uh,
29:01
you know, and maybe this is the episode that
29:03
connected those two dots for some, someone
29:06
out there to be the one who makes that
29:08
discovery. You heard it here folks, on Space
29:10
Nuts.
29:11
Professor Fred Watson: That's one of the reasons why we do it. Who
29:13
knows who's listening and might make a
29:16
brilliant discovery. Space Nuts is to
29:19
blame.
29:20
Heidi Campo: Space Nuts, Yeah. Uh, you can give us a
29:23
little note on the acknowledgement
29:24
acknowledgments on your manuscript.
29:25
Professor Fred Watson: That's right, yeah, absolutely.
29:27
Heidi Campo: Well, thank you so much, Fred. This has been
29:30
a lovely conversation. I really enjoyed
29:32
chatting with you today and I will look
29:35
forward to talking to you again in our
29:38
Q and A episode. Uh, next.
29:40
Professor Fred Watson: Sounds great. Thanks Heidi.
29:42
Andrew Dunkley: Hello Heidi. Hello Fred. And hello Huw
29:45
in the studio.
29:45
Andrew here from the Crown Princess. Uh,
29:47
we're a month, over a month now into
29:50
our world cruise and since I spoke to you
29:53
last, uh, we have been super busy. We
29:56
got around the Horn of Africa eventually and
29:59
we stopped in Cape Town. Weather wasn't
30:02
great, but uh, it did clear up. And
30:05
uh, we had a fabulous two days there.
30:08
And we went out on a um, a ah,
30:11
safari which was a couple of hours drive out
30:13
of Cape Town. And uh, saw some fabulous
30:16
uh, scenes. Beautiful uh,
30:19
animals. Giraffes. We saw a baby
30:21
rhino that was apparently born that day
30:24
trailing along behind its mum. So it got its
30:27
legs sorted out. And we
30:30
saw buffalo, uh, we saw lions.
30:33
And we got up close with them. They, they
30:36
actually came up to our vehicle. Beautiful
30:38
uh, creatures. Um, didn't
30:41
feel too apprehensive about them being, you
30:43
know, face to face. But uh, it was, it was
30:45
terrific and uh, plenty of other
30:48
things. And then the next day we went
30:51
to um, a colony of
30:54
penguins at a place called Boulders Beach.
30:56
They're the African penguins. They're highly
30:59
endangered and they were so cute.
31:01
And uh, a lot of uh, babies. Uh,
31:04
there as well.
31:05
Andrew Dunkley: So got to see all that. And Cape Town was
31:08
fabulous. And by the time we were leaving and
31:10
the ship was pulling out, the skies cleared
31:13
and we got to see the famous Table Mountain.
31:15
So, uh, yeah, just a terrific time.
31:18
And then two days sail later, we were in
31:21
Namibia. Now we were told, uh,
31:23
by uh, the people on the ship not to expect
31:26
much, that um, Namibia, Walvis
31:29
Bay, particularly Was a bit of a backwater
31:31
and uh, it wouldn't be, uh, the
31:34
greatest stop, uh, to
31:37
make. But, uh, we would
31:40
like to disagree with the cruise staff
31:42
because we had a fabulous time. We went out
31:45
four, uh, wheel driving on the, on the sand
31:47
dunes that Namibia is famous for. We went
31:50
out on Walvis Bay and saw more,
31:53
um, living creatures than we've
31:56
seen anywhere. Colonies of thousands of
31:59
seals, fur seals who came swimming up to the
32:01
boat to say hello. What's all this then?
32:05
Ah, Fred would understand that accent. And
32:07
one of them actually jumped in the boat and
32:10
obviously was used to being around people.
32:13
We, uh, got visited by a pelican who jumped
32:15
on board. We got visited by a seagull who
32:17
jumped on board. Uh, we visited the, the salt
32:20
pans. Salt is a major export of Namibia. Ah.
32:23
Andrew Dunkley: And you know, we were driving along with
32:26
sand dunes on the left and the Atlantic Ocean
32:29
on the right and only a track to,
32:32
um, separate them. And uh, it was just
32:35
amazing. Just an incredible country. Such
32:37
lovely people. And I would highly
32:40
recommend, uh, Walvis Bay and Namibia to
32:43
everybody. They're just about to make an
32:44
announcement, so that'll probably interrupt
32:46
me, but I won't stop because I'm nearly
32:48
finished. We are now heading
32:50
northwest. Our next stop, uh, is Tenerife
32:54
and I, uh, believe. I believe we
32:57
just, um, uh, passed
33:00
the day that is where, uh, the
33:03
Earth is the furthest from the sun. So that's
33:05
my little astronomical analogy for you today.
33:09
And I'm uh, a fellow aphelion. Is that
33:12
what it's called? I think I'm right. Fred,
33:13
uh, will correct me. But anyway, that's where
33:16
we're up to. Tenerife, next stop. And I'll
33:18
report in again real soon. Hope everyone's
33:21
doing well. I'll try and see. Post some
33:22
pictures on the Facebook page. I just keep
33:24
forgetting. And the Internet here is, um,
33:27
clunky at best, but we're managing. All
33:30
right, talk to you all soon. Bye bye.
33:32
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33:35
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