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ABC Listen, podcasts,

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radio, news, music and

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more. Hello

0:08

again, Robin Williams. Time for

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The Science Show with the exoplanet Queen.

0:25

And apart from Queen, Jessie will have Carl

0:27

Smith in Berlin with the Falling

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Walls meeting and Alexandra de Blass

0:31

in Tasmania, seeing how a rare

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fish escape is being rescued from

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extinction by using oxygen. First,

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naturally, we turn to royalty, a prime

0:40

candidate to join our top 100 scientists.

0:44

Jessie Christensen is at Caltech

0:46

in Pasadena. She gained

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her astronomical qualifications in Griffith in

0:51

Brisbane at the ANU and then

0:53

the University of New South Wales. She's

0:55

now with NASA in California. May

0:58

I comment about your clothing? Exoplanet

1:01

Queen, it says, boldly. It

1:03

does, it does. How do you justify that? I

1:06

am the woman who has found the most planets

1:08

in the world, having found 66. Don't

1:11

compete with some of the guys, but I'm the most

1:13

successful woman planet hunter in the world. And

1:16

how many numbers do the guys actually claim?

1:19

So my colleague Tim Morton has

1:21

found 1,275 and another colleague,

1:23

Jason Rowe, has found over 700. When

1:26

I last saw you a few years ago, did

1:29

you have any dream that it will be numbers

1:31

on that scale? I really didn't.

1:33

We had expectations, but everything had to work out

1:35

right. With all of our missions and all of

1:37

our projects and all of our data, we had

1:39

to find thousands of planets and we did. And

1:42

we think we're going to find tens of thousands

1:44

more. By what means? Many means?

1:47

Yes, there's a few different ways of finding

1:49

planets that are going to boom in the

1:51

next five years. So there's a European mission

1:53

called Gaia, which is using astrometry, which is

1:55

measuring the position of the star really precisely.

1:58

It's expected to find up to seven. and

2:02

then the Nancy Grace Roman Space Telescope that NASA

2:04

is launching is going to use two different methods.

2:06

One is called microlensing, basically magic that Einstein laid

2:08

down the equations for and it's supposed to find

2:10

thousands of planets with microlensing and then the big

2:13

one with Roman is the transiting method. So that's

2:15

the method where the planet goes in front of

2:17

the star and blocks some of the light. When

2:19

you measure the light you see it dimming and

2:21

it's going to find a hundred thousand transiting planets.

2:24

And you're going to get that information pouring

2:26

at you on your desk so you can

2:28

analyse what the planet is like. Yes,

2:30

that's the advantage of analysing space data. I just

2:33

get to sit at my desk and it all

2:35

comes to my laptop beautifully reduced. And

2:37

you never go up and look at the

2:39

telescope and see the stars? Very

2:41

occasionally, a few nights a semester I get to

2:44

go to a nearby observatory called Palomar Observatory which

2:46

is a wonderful old telescope, the big eye on

2:48

the sky it was called. It was the biggest

2:50

optical telescope in the world a hundred years ago

2:53

and it's really wonderful to get to

2:55

go. I do miss going more but I get to

2:57

go sometimes. What we get from the

2:59

NASA spacecraft, the data that I analyse are candidates.

3:02

We see little wiggles and they might be planets

3:04

but they might be something else. There's a bunch

3:06

of other things they could be. So I do

3:08

things like go to Palomar Observatory or remotely use

3:10

the Keck telescopes in Hawaii or the Gemini telescopes

3:13

in Chile to look much closer and find out

3:15

what it actually is that's orbiting the star and

3:17

creating this little wobble that we see. That's the

3:19

hard work. You find thousands and thousands of candidates

3:22

and then you have to spend hours and hours

3:24

turning each one into either a confirmed planet or

3:26

a false positive. And with all

3:28

of that number are they all characteristically different

3:30

from each other or can you say that's

3:32

another one of them, that's another one of

3:35

them, they're only about five or six types?

3:38

There was this really interesting cultural shift in

3:40

the field a few years ago as we

3:42

got into thousands of planets where every individual

3:44

planet isn't necessarily exciting anymore. If you have

3:47

a paper that comes out with 60 planets

3:49

in it which my most recent paper did, I can't

3:52

tell you about each one individually. I don't

3:54

know about the 13th planet in the paper

3:56

or the 27th planet. You just start to

3:58

analyse them in bulk. So it used

4:00

to be the case that everybody knew every

4:02

exoplanet. You'd be like, had p7, of course,

4:05

that's the one with the variable atmosphere. And

4:07

now you're like, Kepler-612, uh, was

4:09

that one of the rocky ones? Like

4:12

we've totally lost the ability to know all the

4:14

planets, which is a shift. But in terms of

4:16

the classes of planets, we do

4:18

see broad classes. So there are

4:20

hot Jupiters. Ah, with tails.

4:22

Yes, yes, most recently one of them came out

4:24

as having a tail. There's a few now we

4:26

think that have these big tails. So

4:29

there's hot Jupiters, which are gas giants, very close to

4:31

the star. There are Neptunes and sub-Neptunes, ice

4:33

giants that are just a bit smaller than

4:35

Neptune and Uranus in our solar system. We

4:38

have something that we call super-Earth, and we

4:40

actually don't have a good idea what those

4:43

are. Whether they're just scaled up rocks or

4:45

scaled down ice giants, or there

4:47

are proposals that they're like water worlds, right? That they

4:49

have a deep water ocean that covers their surface. We

4:51

don't have anything like that in our solar system, so

4:54

it's hard to know, but we think they could exist.

4:56

And then finally, we see the little rocks. We've just

4:58

gotten sensitive enough to start to see the little

5:00

rocks, and those we're excited by, because that could

5:02

be home. I was astounded, by the way, just

5:04

as a diversion to hear the other day that

5:06

there was a moon of Saturn, I think, that

5:09

turns out to have an ocean underneath. And

5:12

you heard of that? Yes, that's Mimas. So actually, one

5:14

of Mimas' claim to fame, if you've ever seen

5:16

a picture of it, it's the one that looks

5:18

like a Death Star. It's got the big divot

5:20

taken out of the side. So when we think

5:22

about looking for life in our solar system, one

5:24

of the things we're thinking about is liquid water.

5:26

Where is there liquid water in the solar system?

5:28

We know in the past, there was liquid water

5:30

on Mars. We see evidence of water rushing over

5:32

the surface and leaving things behind. But

5:35

elsewhere in the solar system, the liquid

5:37

water is in these subsurface oceans.

5:39

So Enceladus is another

5:41

moon of Saturn. Europa is a moon

5:43

of Jupiter. And now Mimas is this

5:45

second moon of Saturn that seem to

5:47

have these subsurface oceans. And that's really

5:49

exciting, because we think that all life

5:51

on Earth needs liquid water. There's not

5:53

much else that all life on Earth

5:55

needs. Life is really great about filling

5:57

up all of the evolutionary and ecological

5:59

niches. But we only liquid water.

6:01

So finding liquid water. And a new

6:04

moon of Saturn could be super

6:06

super cool. Nine others happens quite

6:08

large compared say to Mercury Buzzers

6:10

Moon. Moons. A smaller

6:12

himself notion. Of further out

6:14

in the solar system in law the more the

6:17

water content is Actually if you think about the

6:19

of regional distribution of water in the solar system

6:21

most of the water condensed way out in the

6:23

outer solar systems Uranus and Neptune has would us

6:26

just not liquid water like the water were looking

6:28

for. So these rocks are formed from the detritus

6:30

of comets and asteroids in the electoral system. Everything

6:32

somebody each other and then the material settles right.

6:35

You get rock in the middle and in the

6:37

next heaviest thing as water and then you expect

6:39

something like an atmosphere on top. but if the

6:41

top of the water freezes and you get the

6:44

shell. Of ice and rock that sleazy

6:46

the subsurface ocean. Mazer.

6:48

Yes, But back to these planets. How

6:50

many a clinton? How many are Not.

6:53

So actually this is kind of exciting. The

6:55

very close to star to our solar system.

6:57

it's called Proc them to send Tory. It's

6:59

part of a three star system with Alpha

7:01

Centauri I in Alpha Centauri be in Australia,

7:03

that office and Tories one of the pointers

7:05

like that's an obvious on we know that

7:08

one that are closest star system Brooklyn a

7:10

Centaur. He had a rocky planet in the

7:12

habitable zone of that starts at the rocky

7:14

planet. that's the right temperature. the liquid water.

7:16

that's our nearest neighbor. like when we go

7:18

out to the Galaxy Nasr cup of sugar

7:20

Proximate Centaur is right there. It's three point

7:22

eight. Light years away which is

7:24

to say it's quite fast us

7:27

that that's because faces really big

7:29

city. But if we got the speed of

7:31

light we given free have his. Yes, and

7:33

things like radio emissions from earth or laser

7:35

transmissions like we want to send messages. It's

7:38

gonna take nearly four years, but that's the

7:40

time scale were looking so that's only an

7:42

eight year round trip for communicating synthetic. Some

7:44

of the other plans we found a much

7:46

further away. amazing isn't it so

7:48

are you just gonna continue from

7:50

sixty six to two off thousand

7:52

is it a case of accumulate

7:54

more more and sub some stage

7:56

you'll see patterns in these planets

7:59

that a more like Earths and therefore you'll

8:01

be able to home in on something? Yes.

8:03

So there's this famous Ernest Rutherford quote,

8:06

which is, all science is stamp collecting

8:08

or physics. So we've been

8:10

stamp collecting for a long time. And they

8:12

gave him the prize in chemistry despite him.

8:16

So we've been stamp collecting for a long time in Exoplanet.

8:18

So you're asking about whether we're just going to keep collecting

8:20

more. I hope so. And I'm going to keep looking for

8:22

more. But it's the physics. It's the

8:25

underlying patterns and reasons why things are happening the

8:27

way we are. Why are we finding rocky planets

8:29

in the habitable zones of these stars? What does

8:31

that tell us about how planets form and how

8:33

they evolve and how they migrate? What does it

8:35

tell us about the future of our solar system?

8:37

What's going to happen to us in five billion

8:39

years? One of the most exciting developments

8:42

for me for the last few years is finding planets

8:44

around white dwarf. So our

8:46

sun is just a boring middle-aged G

8:48

star. In five billion years, you might have

8:50

heard it's going to expand to a huge red giant, swallow

8:53

up Mercury, swallow up Venus, maybe swallow the Earth.

8:56

And there's this open question for a long time,

8:58

do planetary systems survive this stage? Can you have

9:00

planets after the red giant stage? So

9:02

after the star becomes a red giant, it puffs

9:04

off all its outer layers, hopefully it becomes a

9:06

beautiful planetary nebula. And then what's left behind in

9:08

the middle is a white dwarf, just a

9:10

little cooling chunk of carbon and oxygen. And

9:13

we've started finding planets around nearby white dwarfs,

9:15

which means they can survive, which means our

9:18

solar system might survive. This is first evidence

9:20

that we might still be around after five

9:22

billion years. You mentioned Ernest Rutherford.

9:24

In the science show shortly, I'm

9:26

broadcasting a program about Sir Mark

9:28

Oliphant, who was the first person

9:30

to be head of the Australian

9:33

Academy of Science and

9:35

was the right-hand man literally

9:37

of Ernest Rutherford. Rutherford

9:40

was a rather clumsy man. There's

9:42

a wonderful sign in this laboratory, we don't have

9:44

the money, therefore we must think. And

9:47

he was able to think because Mark was doing the

9:49

work for him. And I

9:52

found a recording of him from

9:54

1931 talking about gamma

9:56

rays and alpha rays and so on. That's

9:59

very cool. I'm looking forward to hearing that. Do

10:01

you think many people remember who he

10:03

was? You're the first person that I've met

10:05

who's known someone who's known him. So I think

10:08

no, I don't think many people still remember. We

10:10

remember the quotes and we remember the science, but

10:12

not the person. So having the recording is super

10:14

exciting. I'll tell you when it's on and you can

10:16

listen. I will. Thank you. Thank

10:18

you so much. The irrepressible Dr. Jesse

10:20

Christiansen lead scientist at the

10:22

NASA Exoplanet Archive based at

10:24

Caltech in Pasadena. From

10:27

Australia, and yes, one of the science

10:29

shows top 100 soon. She's

10:31

queen after all. And

10:34

that special science show on Sir

10:36

Mark Olyphant will be soon with

10:38

Ernest Rutherford showing how his role

10:40

in World War II, not shown

10:42

in the Oppenheimer film, was

10:44

crucial. Here's his grandson,

10:46

Michael Wilson, in Canberra. Michael,

10:49

good to see you after all this time. Good

10:51

to see you, Olyphant. One of my favorite people

10:53

in Australian history, Mark Olyphant. Would

10:55

you remind us what sort of scientific

10:57

research is he famous for? So when

10:59

I talk to people who don't

11:01

know who Mark Olyphant is, I might

11:03

have casually dropped in conversation that I'm

11:06

related to him and they ask what

11:08

he did. I say, well, have

11:10

you got a microwave oven? Because

11:12

the cavity magnetron, which makes every

11:15

microwave oven work, was

11:17

an invention of Mark's

11:19

team at Birmingham University

11:22

when he was professor of physics

11:24

there. But more importantly, it was

11:26

invented as a tool for helping

11:28

the Allies to win the war

11:31

against the Axis powers because it's at

11:33

the center of microwave radar, which allowed

11:35

you to take something that used to

11:38

be housed in a building and put it in

11:40

the nose of an aircraft. He came back to

11:42

Australia, which was very interesting, because

11:44

he could have stayed there indefinitely. Why

11:46

did he come back? He

11:48

felt that studying science

11:52

and doing scientific research at

11:54

a world-class level, was an

11:56

important capability that Australia needed

11:59

to do. develop. Let me just

12:01

quote to illustrate his idealism. He said,

12:03

I have a deep confidence in the

12:05

part which science can play in making

12:07

us strong and prosperous. He's talking about

12:10

Australia of course. And an

12:12

idea that the proper use of

12:14

science within its diverse territories may

12:17

point the way to a secure and

12:19

good life for all, for the

12:22

community. The idealism is

12:24

so strong. Indeed the community and

12:26

the population of the world. And

12:28

when you think about some

12:31

of the scientific discoveries he'd been

12:34

involved with in particle physics, in

12:36

terms of you know the team

12:39

at the Cavendish, at Cambridge that

12:41

spit the atom. His work later

12:44

on Microwave Radar and his work

12:46

on putting atomic physics into

12:49

play to, as they felt at the

12:51

time, win victory in the Second World

12:53

War. His view of

12:56

science and learning was

12:59

fundamentally connected to his

13:01

view of the well-being

13:03

of humanity and the advancement of

13:05

humanity in all fields. Michael

13:08

Wilson, grandson of Mark Oliphant, who was

13:10

also the first president of the Australian

13:12

Academy of Science, founded exactly 70 years

13:14

ago and a founder of

13:17

the ANU, the Australian National University.

13:20

Science show on St. Mark with

13:22

Rutherford on soon. But

13:24

now we leap across to Berlin and falling

13:26

walls. A great meeting, a

13:28

festival to celebrate top science. And

13:31

it'll include more on that brilliant

13:33

Gaia satellite. Here's Carl Smith. It's

13:36

a bright autumn day. A cold wind

13:39

is blowing down the Spree and

13:41

just up river from the Eastside Gallery at

13:43

a converted pumping station that once sat at

13:45

the edge of the Berlin Wall. Scientists,

13:48

students, entrepreneurs and industry are gathering

13:50

to share some of the most

13:52

exciting research breakthroughs of the past

13:55

year. Creative solutions

13:57

for our oceans to soak up CO2 from

13:59

sea. grass to ocean beds, unlocking

14:02

the lingering mysteries inside cells,

14:05

or taming the wave of AI that's about

14:07

to crash into every part of our lives.

14:10

The Falling Walls Festival's guiding question is

14:12

what are the next walls to fall

14:14

in science and society? And

14:16

I met with a few of those being celebrated

14:19

at the 2023 event, including one

14:21

of the breakthrough speakers, Argentinian astronomer

14:23

Professor Amina Helmi, now at the

14:25

University of Groningen in the Netherlands.

14:28

She's been helping decode an incredible

14:30

number of bright points from our

14:33

galaxy, collected by the European Space

14:35

Agency's multi-million dollar Gaia spacecraft. Professor

14:38

Helmi, you work in the field of galactic archaeology,

14:40

so let's just start with what that is.

14:43

The basic idea is that you

14:45

can actually use stars to reconstruct

14:47

history. Stars remember where they

14:49

come from, in the way they

14:51

move, in their chemical

14:53

composition that tells us about where

14:56

they were born, and in

14:58

their ages, which tells us when they

15:00

were born. So using all of that

15:03

information, we can use the present-day properties

15:05

of stars to rewind the

15:08

movie back to reconstruct how our

15:10

galaxy was put together. Now,

15:13

you're involved in the Gaia mission, I believe, since

15:15

its inception. Can you tell

15:17

me a little bit about the mission

15:19

and also why it's helping us look

15:22

at this galactic archaeology? The

15:24

mission was conceived in the 90s. It

15:27

was meant to produce a three-dimensional

15:30

map of the galaxy, a billion

15:32

stars, and to measure

15:34

how the stars move through space. Every

15:37

object that's sufficiently bright will

15:40

be in that database. And

15:43

so Gaia observes the sky every

15:45

six months. The key questions were,

15:47

how did the galaxy form? There's

15:51

also a lot of serendipitous

15:53

discoveries that come out of this mission.

15:55

And it turns out that the mission

15:58

quality is so high. Initially,

16:00

in Visage, it would last for five

16:02

years. But it's now

16:04

actually been observing for 10 years. And

16:07

it may last a little bit longer.

16:09

So it's an amazing data set. And

16:11

the kind of things that we can

16:13

see now are unbelievable. We can even

16:16

monitor quakes in stars. So

16:18

those are called star quakes. We have the surface of

16:20

the star kind of shutters. Yeah, and

16:22

that tells us about the internal structure

16:24

of the stars. We are beginning to

16:26

see extra solar planets. What

16:29

I really like about this mission is

16:31

that there's so many

16:33

astrophysical applications. And just in

16:35

case people haven't heard of Gaia before, it's

16:37

a space-based telescope. It was launched in 2013.

16:40

And what really made it stand out was

16:42

its power, its precision. Indeed,

16:45

Gaia measures very accurately the positions

16:47

of stars through time. And it

16:49

does in such a way that

16:51

you need a 10-microarcsecond precision. And

16:54

that's equivalent to being able to

16:56

measure the size of a euro

16:58

coin on the surface of

17:00

the moon. Impressive. It

17:03

is very impressive. Yes. You've

17:06

used this data to help map

17:09

and create an immense 3D model of

17:11

the Milky Way. How has this helped

17:13

us to understand the history of

17:15

our galaxy? So using the

17:17

motions, we can actually tell

17:19

where stars were born. And

17:22

so that is where we needed to

17:24

unravel what we call mergers.

17:27

So we think galaxies formed by

17:29

a merger. So early on, the

17:31

first galaxy to form was more.

17:33

And because of gravity, they merge.

17:35

They are cannibalized by other systems.

17:37

And the memory of this process

17:39

is actually in the motions of

17:41

the stars. And one of the

17:43

first things we did with the

17:46

second data release of the Gaia mission,

17:48

which had the motions of so many more

17:50

stars than we had ever

17:52

before, was to look

17:54

for the signatures of the mergers. And

17:57

we found one. So

17:59

this is the. mega crash that we were talking about

18:01

some 10 billion years ago. You

18:04

used a great analogy in your talk. You

18:06

mentioned entering a roundabout as someone from say

18:08

the EU driving on the right side of

18:10

the road and spotting an Australian

18:12

or a British driver who's driving on the left

18:14

side of the road and entering the other way.

18:17

Some of the stars are floating

18:19

clockwise around the Milky Way Center

18:21

and others are going anti-clockwise and

18:23

that's the clue that let you

18:25

figure out there was this enormous

18:27

crash. Indeed, that was amazing that it

18:30

was so simple. We didn't

18:32

know what to expect but

18:34

most stars in our galaxy like the

18:36

Sun they just rotate clockwise around the

18:39

center and then among the oldest stars

18:41

that we have in our galaxy we

18:43

see that roughly half of them go

18:45

the other way and it

18:48

means that they come from somewhere else

18:50

and then if you look we analyze

18:52

the chemical compositions of those stars and

18:55

they are distinctly different from those

18:57

born in our galaxy. Any signs

18:59

that there might be any other galaxies

19:01

in the mix that were merged

19:03

in with the Milky Way as well? Yeah

19:05

so we're currently eating up another

19:08

galaxy that's known as the Sagittarius

19:10

dwarf. It's a small object.

19:12

It's just a tiny galaxy. It

19:14

is not doing a lot of damage although

19:17

Gaia data actually is showing us it's doing

19:19

more than what we saw it was. This

19:21

is stars bumping into other stars? Not

19:24

that but it's actually shaking a bit

19:26

the Milky Way. So the idea is

19:28

what you have is basically gravity at

19:31

work so just like the

19:33

Earth is distorting the Moon because of

19:35

tides the Moon has also an effect

19:38

on the Earth and that's the tides

19:40

that we see on the oceans. So

19:43

it's that kind of similar distortions

19:45

that we then see on galactic

19:47

scale but the real big

19:49

one was this one 10 billion years

19:51

ago and what we're trying to do

19:53

at the moment is to go back

19:55

even further in time. What happened before?

19:58

What happened between the big ones? and

20:01

those 10 billion years ago. The

20:03

Gaia dataset is enormous. It's two

20:05

billion objects, and for each object,

20:07

you have something like 100 properties.

20:10

And so searching or gathering

20:12

the information you're after from

20:15

this dataset is challenging. So

20:18

we developed in our group a

20:20

software package that's called VEX, which

20:22

is publicly available, which is

20:24

able to visualize and allows

20:26

you to explore one billion

20:28

objects in one second. Where's

20:31

your next for Gaia? This satellite is still

20:33

up there. It's still doing some important work.

20:36

Where's it looking now? Yeah, so

20:38

now it's been extended. It's actually the

20:40

last phase, so it spins, and it

20:42

manages to observe the full sky every

20:44

six months. And as you do this

20:46

more and more often, what that means

20:49

is that you're able to determine the

20:51

positions of stars more

20:53

accurately. And so that allows

20:55

us to actually measure how

20:57

stars are moving inside other

20:59

galaxies outside of the Milky

21:01

Way. Incredible. Professor Amina Helmi, thank you

21:03

so much for taking the time to talk. Thank

21:05

you, it's been great talking to you. Professor

21:08

Amina Helmi from the University of Groningen.

21:11

And each year, the Falling Walls Festival

21:13

also selects breakthrough award winners in different

21:15

fields. In the field of

21:18

engineering and technology, this year's breakthrough winner

21:20

is material scientist Kao Tang Din, originally

21:23

from Vietnam, but now at Queen's

21:25

University in Canada. Putting

21:27

the genie back into the bottle. That's

21:29

what many scientists are working on. Fossil

21:31

fuels have been a fairly magical tool

21:34

that's powered industrialization around the world, but

21:37

the CO2 that's been emitted is changing our

21:39

world's climate. For more than

21:41

100 years, we've known it is possible to

21:43

grab CO2 from the atmosphere and convert it

21:45

back into something else we can use, making

21:47

new sources of fuel or chemicals out of

21:49

thin air. But Assistant Professor

21:51

Kao Tang Din from Queen's University has

21:53

been working on new ways to improve

21:55

this process, and maybe just to start.

21:57

Can I get you to tell me the scope? of

22:00

the problem that we're dealing with here. Huge

22:02

problem. We are releasing billions of

22:05

times of CO2 per year, like

22:07

40 billion times to be exact.

22:10

We need to bring down it to zero

22:12

in 2050. So

22:15

that is a big task and we

22:17

will need a lot of technology to

22:19

achieve that goal. Now this

22:22

process of taking CO2 from the atmosphere,

22:24

it's been around for a long time.

22:26

So what's been the problem with us

22:28

just doing this? Taking CO2 out of

22:30

the atmosphere from the industrial process

22:32

is not a big challenge. Doing

22:35

the conversion is another issue. The

22:37

cost is the main issue

22:40

for now. But also it depends on

22:42

what kind of product you want to

22:44

produce from CO2 for simple

22:46

product. Then we are close to

22:48

the demonstration at large scale for

22:51

more complex product than we are still

22:53

in the early stage. What sort of

22:55

products can we make out of CO2

22:57

that we take out of the atmosphere? Mostly in

23:00

a hydrocarbon gas or liquid fuels

23:02

that we are using for our

23:04

car, for example. But you

23:06

can also combine carbon dioxide with

23:09

nitrogen, for example, and you can

23:11

make even fertilizer. Regarding

23:13

the product that I'm working on

23:15

two things, making fuel out of

23:17

CO2, I also work on ethylene,

23:20

which is a precursor for the

23:22

plastic production. Each year we produce

23:25

100 million tons. Think about the

23:28

CO2 scale, that is billion tons scale. So

23:30

if you choose a product, if you want

23:32

to make a big impact, that should have

23:34

the large market, so we can convert a

23:36

lot of CO2. The main application

23:38

for ethylene is to make the point

23:41

of ethylene, the plastic bottle that we

23:43

use every day. How do you take

23:45

CO2 from the atmosphere and

23:48

then somehow turn it into these

23:50

chemicals? The system we are working

23:52

on, we do also the capture,

23:54

we dilute the CO2 into a

23:56

solution and we feed that solution

23:58

into the reactor. The key... thing

24:00

here is how you design an electrode

24:02

which is inside the reactor when the

24:05

CO2 is converted. How do

24:07

we design an electrode that enables

24:09

that process? That is the key

24:11

thing. In 2018, you

24:13

published a paper in Science that showed

24:15

that a new catalyst that you designed,

24:18

a new electrode that you designed, allowed

24:20

greater efficiency over a significant time frame.

24:22

Now these are both important things. Tell

24:25

me about what you did in that

24:27

process. At that time, the best system

24:29

for CO2 conversion to ESNN lasts for

24:31

only a few hours. We discovered that

24:34

the main reason for the failure of

24:36

CO2 conversion to ESNN is

24:38

the degradation of the electrode where

24:41

the CO2 is converted to ESNN.

24:43

Instead of using the traditional

24:45

way, we add a protecting

24:47

layer and by using that

24:49

design, we can maintain the

24:51

ESNN selectivity for over 150

24:53

hours. Just

24:56

to give us a sense in terms of numbers, how

24:59

does the efficiency of this

25:01

process compare to other similar models?

25:03

In terms of selectivity, we are doing

25:05

pretty well. We got up

25:08

to 70%. Our

25:10

target is about 90-95%. We

25:12

are quite close. In terms

25:14

of reaction rate, how fast

25:16

you can convert CO2 to your product,

25:18

we are doing well in that aspect

25:21

as well. We reached our goal of

25:23

the reaction rate. A great progress in

25:25

the last couple of years because 10

25:27

years ago is only a few hours.

25:30

Alongside getting this tech to work efficiently, I

25:32

believe there's another element that could really unlock

25:35

this process, which is affordable

25:37

renewable energy. Yes, because the

25:39

whole idea here is that

25:41

we convert the carbon dioxide

25:43

back to the fuel. If you use

25:45

the fuel to generate electricity, then it

25:48

doesn't make a lot of sense. If

25:50

we use the renewable electricity with the

25:52

low carbon footprint, then we

25:54

had a chance to produce the product with

25:56

low carbon footprint. That is the whole idea.

26:00

process that you're working on is the one and

26:02

only solution to this problem of pulling carbon dioxide

26:04

out of the atmosphere and finding better ways to

26:06

use it. We are talking

26:08

about billion-time CO2 emission here and I

26:10

don't think that there is a single

26:13

technology that can deal with that challenge.

26:15

So of course it will require a

26:18

lot of different type of technology. The

26:20

most important one is trying to reduce

26:22

the CO2 emission in the first place

26:25

and this is important when people think

26:27

that oh you can do CO2 capture

26:29

and conversion you can just okay burn

26:32

whatever you want to burn but in

26:34

reality is CO2 capture and conversion should

26:37

be the last option for you

26:39

to deal with the CO2 emission.

26:41

Assistant Professor Kao Tang Din from

26:43

Queen's University in Canada and

26:45

Australians were also on the winners podium

26:47

at the festival. My name

26:50

is Emma Ann Carlson I'm a PhD

26:52

student at the University of Queensland

26:54

Fraser Institute and I'm also

26:56

a general surgery registrar at the Mater Hospital

26:58

in Brisbane. And you've just won one of

27:00

the emerging talents prizes here at the Falling

27:02

Walls festival for 2023. Tell

27:05

us about your project. My

27:07

project is working with associate professor

27:09

Fiona Simpson and we're

27:11

repurposing an anti-nausea medication

27:13

called Prochloraparazine to

27:16

improve the way that some monoclonal

27:18

antibodies are used to treat cancer.

27:21

So there's existing cancer medication and

27:23

you're trying to improve the efficacy

27:25

of that medication using an

27:28

anti-nausea drug? Exactly. A lot

27:30

of people would know chemotherapy which can be

27:32

a bit like a bulldozer when it comes

27:34

to treating patients. There's lots of side effects

27:36

and it's not very specific. Monoclonal

27:39

antibodies are amazing because they're targeted

27:41

therapy that goes directly onto receptors

27:43

on the cancer cell surface but

27:45

we're running into an issue where

27:48

a large proportion of patients up to 70%

27:51

don't respond to these medications. What

27:53

the anti-nausea medication does is inhibits

27:55

the internalization of those receptors. So that basically means

27:57

that there's more receptors on the cancer cell surface.

28:00

on the cancer cell surface for those

28:02

medications to bind to and

28:04

actually help promote clearance of the tumor by

28:06

your patient's own immune system. Have you shown

28:08

this in patients? Not yet. We've

28:10

done the lab work. We're really

28:12

lucky to be collaborating with the PA Hospital

28:14

in Brisbane and St. Vincent's Hospital in

28:17

Sydney, where we are now in a

28:19

safety trial to prove that this is

28:21

safe in patients to use. And once

28:24

we've done that, we'll progress the larger

28:26

efficacy trials in the hope that this

28:28

will become standard practice in Australia and

28:30

the world. So you mentioned that the

28:33

chemotherapy drug that you're talking about here,

28:35

it costs a pretty exorbitant amount of

28:37

money, but this anti-nausea drug, which can

28:39

potentially improve efficacy only costs, say, $20

28:42

through the Australian PBS scheme. So

28:44

this sounds like a very good value add. Absolutely.

28:47

And that's exactly why we're super passionate about

28:49

it. We've estimated that the average

28:51

cost to Australia per year for non-responders

28:53

to this medication is over $355 million.

28:58

If we could make each patient who

29:00

receives this medication respond better with just

29:02

$20 of extra value, that would be

29:05

incredible. Do you have any sense of

29:07

how much this would improve survivability or

29:09

clearance of the cancer? We'll

29:11

have to see how our efficacy trials go,

29:14

but our mouse models and our lab work

29:16

has been very exciting so far. Now

29:19

alongside being a practicing doctor and doing your

29:21

PhD, you've also found some space to communicate

29:23

this work. What's it been like stepping into

29:25

this space of talking about your research as

29:28

well? It's been very exciting. This

29:30

all started as a tool of me

29:32

overcoming some pretty bad stage fright and

29:34

performance anxiety that I've had. Well, thanks

29:36

for talking into the microphone now. And

29:39

my supervisor recommended that I get

29:41

out there more and practice on

29:43

my research communication, and it really

29:45

has helped in also understanding my

29:47

science better to be able to communicate it on

29:50

a basic level to people who may not be from

29:52

the same background as you. And

29:54

any advice as a young researcher overcoming

29:56

stage fright and stepping out onto the big stage,

29:59

the global stage? and being named an

30:01

emerging talent here. Throw your hat in

30:03

the ring. I think that it's in

30:05

the Australian spirit to be very humble

30:07

and to be scared of being

30:10

proud of your work, but it's really

30:12

a fantastic opportunity to meet others and

30:14

to learn your science better as well.

30:16

Emma, thank you so much and congratulations.

30:18

Thank you very much. Appreciate it. Emma

30:21

Jane Carlson from the University of Queensland with

30:23

Carl Smith at the Falling Walls event

30:25

in Berlin celebrating research

30:27

that makes walls go down

30:30

revealing enlightenment. And this

30:32

is The Science Show on our end. And

30:34

so to Tasmania, where if you saw

30:37

the report on 730 ABC television this

30:39

week, there is more on

30:41

the way of putting oxygen in depleted

30:43

water and how it can save so

30:45

many fish that otherwise may die. Alexandra

30:48

de Blass reports. In

30:52

May last year, scientists at

30:54

the University of Tasmania published

30:56

an alarming report on the

30:59

endangered Morgean skate. The

31:02

population in Macquarie Harbour on Tasmania's

31:04

west coast had halved

31:06

over seven years and

31:08

its juveniles were not surviving. The

31:12

main cause of the skate's decline and

31:14

its future threat is

31:16

low levels of dissolved oxygen. This

31:19

is compounded by weather events

31:21

pushing waters very low in

31:23

oxygen into the skate's habitat

31:25

and killing large numbers of

31:27

animals. The scientists

31:30

called for immediate action. This

31:32

is the most endangered charcarrae species anywhere in

31:35

the world and it would be one of

31:37

the first cases that we know of of

31:40

a marine large vertebrate fish going

31:42

extinct. Dr David

31:44

Moreno is an expert on the

31:46

Morgean skate and a senior research

31:48

fellow at the University of Tasmania's

31:50

Institute for Marine and Antarctic Studies,

31:53

known as IMAS. He

31:55

co-authored the skate report that raised the

31:57

alarm. is

32:00

the only skate species in

32:02

the world of about 400. We

32:04

know that it lives its life exclusively

32:06

in brackish waters. It has a very

32:08

restricted range. It lives in only very

32:10

particular places in the west coast of

32:12

Tasmania. And that means

32:14

that it's probably the shark array species

32:17

in the world with the smallest distribution

32:19

anywhere. Most skates are quite

32:21

similar in shape, but this particular one

32:23

has the same flat body, like a

32:25

stingray. What's different about it is that

32:27

it actually has a very pointy snout.

32:30

It has a very dark brown coloration that

32:32

matches the Tannin water of Macquarie Harbor really

32:35

well. It's fascinating and we

32:37

keep learning more and more about them, for

32:39

example, with our little hatchlings. We now know

32:41

that even more so than other species, they

32:44

have little legs in their pelvic fins that

32:46

they use to walk around the sea floor.

32:48

They suggest the really young ones? No,

32:51

no, no, all of them do it. This form of

32:53

locomotion, but these guys do it a lot. And

32:55

on top of that, there's also a lot under the

32:57

hood that you cannot see that is quite unique to

33:00

these animals. They can cope with conditions

33:02

in low dissolve oxygen or changes in

33:04

salinity in ways that other species would

33:06

not even dream of. So it's pretty

33:08

spectacular. Macquarie

33:19

Harbor is a complex and

33:22

enormous body of water. It's

33:24

six times the size of Sydney Harbor.

33:27

And the Tasmanian Wilderness World Heritage Area

33:29

covers a third of it. While

33:32

it looks stunning, Macquarie Harbor

33:34

is far from pristine. It

33:37

has a legacy of over 100 million

33:40

cubic meters of mine waste in its

33:42

sediments. And acid mine

33:44

drainage is an ongoing source of

33:46

heavy metal pollution. More

33:49

recently, aquaculture has added

33:51

high nutrient loads. While

33:54

hydro dams on the King and Gordon rivers

33:57

have changed the way fresh water flows

33:59

into The associate

34:01

professor Jeff Ross leads the

34:04

IMAS project examining the environmental

34:06

interactions of aquaculture and

34:09

has published many papers on Macquarie Harbour. It's

34:11

highly stratified so it's got a huge influence

34:13

from the Gordon River in particular so it's

34:15

got this really thick freshwater layer that sits

34:17

over the top of it that's full of

34:19

tannins so it's quite dark on the top

34:22

and then it's got marine water underneath it.

34:24

I think one of the key characteristics of

34:26

Macquarie Harbour is it's a bit of a

34:28

bathtub in shape but it's got a really

34:31

narrow shallow entrance to the ocean so that

34:33

means that the water that comes in and

34:35

sits in the bottom it can sit there

34:38

for a long time. The freshwater moves along

34:40

the top and goes out to the ocean

34:42

but that water sits down there in the

34:44

bottom and that's why Macquarie Harbour naturally has

34:47

quite low dissolved oxygen levels in the bottom

34:49

waters because of that unique feature. You've

34:51

been working in Macquarie Harbour for many

34:53

years now. I think oxygen

34:56

rapidly started to decline in 2009. Can

35:00

you paint me a picture of what

35:02

happened and how it's evolved? We

35:05

noticed from about 2009 through the sort of 2012 and 13 that's where we've

35:07

seen the major

35:10

decrease. We saw a few things. If we

35:12

think about oxygen in the bottom waters there's

35:14

been basically a bank balance.

35:16

So it's a balance between demand so

35:18

the things that consume oxygen and

35:21

what supplies oxygen so things like wind

35:23

and waves and we also understand that

35:25

a lot of the oxygen that comes

35:27

into the system comes in from the

35:29

ocean. Bits of plant and organic material

35:31

that consumes oxygen when it falls down

35:33

there and then you add the

35:36

salmon industry which adds a lot of nutrients

35:38

to the water, excess feed and feces that

35:40

go to the bottom so the salmon farming

35:42

added an extra demand. In

35:47

two major weather events that turned over the

35:49

harbours waters in 2019 the IMAAS Morgean Skate

35:54

Project lost 44% of its tagged animals.

36:00

showed that the population had declined by 47%.

36:05

David Moreno. The

36:07

relative abundance has halved. So

36:09

it could be around a thousand animals, could be

36:12

as low as 500, could be a few more.

36:14

But the reality is that it doesn't really matter

36:17

what the actual number is. It's the

36:19

only existing population. There's no margins getting

36:21

worse in the world and when you lose

36:24

half of your population in just a

36:26

few years, that's just not attainable. Late

36:28

last year, a captive breeding program

36:30

was established with $4.2 million

36:33

from the federal and state governments.

36:36

Four adults, Kate, and 50 eggs

36:38

were captured from the harbour in

36:40

mid-December, but two adults died within

36:43

weeks. Professor Jason Simmons

36:45

leads the iMass project and

36:48

despite the losses, he's positive about the

36:50

potential of the captive breeding program.

36:53

Being trapped in Macquarie Harbour for

36:55

tens of thousands of years means

36:58

that there's no diversity in the population. When you

37:00

do genetics, it's virtually impossible to

37:02

find any difference between animals. And so

37:04

that means it'll get to a point,

37:06

if the numbers get low enough, that

37:09

breeding just won't be successful. That's what

37:11

happens when you have no genetic diversity.

37:13

So, yeah, it's got a lot of

37:15

natural things against it and

37:17

then changes of habitat has then put even

37:19

more pressure on it. Low levels

37:22

of dissolved oxygen are a key threat. How

37:25

does it impact the skate itself and those egg cases

37:27

on the harbour floor? The

37:30

eggs on the floor can't use behaviour

37:32

to escape low levels of oxygen. They

37:34

take about seven months to develop. They're

37:37

a closed egg and then about halfway

37:39

through to develop, they open up. Now,

37:42

that's the danger zone. When they open, they'll

37:44

take water in from the outside and

37:47

if that is very low oxygen, then

37:49

that is going to affect their development.

37:52

In terms of the adults, we've done physiology experiments

37:55

looking at tolerance of lower levels of oxygen, and

37:58

they are... quite

38:00

tolerant but their strategy is the

38:02

equivalent of holding your breath. They

38:04

basically will go into anaerobic metabolism.

38:07

They're very tolerant but we've got

38:09

beyond their tolerance levels now. Luke

38:14

Martin is CEO of Salmon Tasmania,

38:16

the lobby group that represents

38:19

the billion dollar salmon industry in

38:21

Tasmania. The industry was

38:23

pioneered effectively in Macquarie Harbour nearly 40

38:25

years ago and one of the major

38:27

reasons was because of the nature of

38:29

the waterway, the protected water space

38:31

but also the few or discarded layers of

38:34

the interquation water and fresh water on top.

38:36

And anyone who knows anything about aquaculture activities

38:38

particularly salmon, they need to clean their gills

38:40

and the nature of having that fresh water

38:42

layer means they're able to do it to

38:44

naturally. 40 years later it's still

38:47

a very efficient and very low risk way

38:49

of undertaking aquaculture on the harbour. And

38:51

what we have seen evolve over the decades is

38:53

a structure around Macquarie Harbour transport network,

38:55

seed mills that have been created in

38:57

the north-west of the state on the

38:59

basis that Macquarie Harbour is part of

39:01

the network and certainly if you were

39:03

to remove aquaculture from the harbour

39:05

it would concentrate in the south-east of the state where

39:08

the growth is and where the majority of the industry

39:10

is and they would have a significant

39:12

impact on the storm which would be quite catastrophic in

39:14

terms of that community but have a flying impact across

39:16

the region. The biomass of

39:19

salmon farming gradually increased in Macquarie

39:21

Harbour from 2007. In

39:24

2012 the federal government gave

39:26

permission to triple the fish biomass

39:28

to 29,000 tonnes. But

39:32

this level was never reached. At peak

39:34

production in 2014-15 serious problems emerged. Large

39:41

dead zones formed around the cages.

39:44

White dorvillered worms multiplied, an

39:46

indicator of low oxygen, and

39:49

thick bacterial mats extended for

39:51

kilometres inside the World Heritage

39:54

Area. Finally in

39:56

2018 the Tasmanian government brought the

39:58

stocking rate to the back to

40:00

pre-expansion limits, but only after farm

40:03

suspender, co-owner of human aquaculture, one

40:05

of the three salmon farming companies

40:08

on the island took the state

40:10

government and two other companies to

40:12

the Supreme Court. So

40:15

what does 9,500 tonnes of salmon and trout look like? I

40:19

spoke with Christine Kochenauer, co-chair

40:22

of the Tasmanian Independent Science

40:24

Council and founder of the

40:26

award-winning Derwent River Estuary Program.

40:29

There's ten leases currently in Macquarie Harbour. Each

40:31

of these leases would probably have somewhere in the

40:33

order of 15 to 25 pens. These

40:38

are 168-metre circumference pens, which are

40:40

some of the largest pens in

40:43

the world, and extend

40:45

to a depth of somewhere in the order of

40:47

20 metres. So at a stocking rate

40:49

of 15 kilograms per

40:52

cubic metre, which is the

40:54

required maximum stocking level, that

40:57

equates to about 90,000 five

40:59

kilogram fish per pen. So you

41:02

multiply that times 15 to

41:04

25 pens per lease times

41:06

10 leases, and you

41:09

have a hell of a lot of fish. And

41:11

these fish, they're breathing, they're excreting,

41:13

there's feed that's unused that also

41:15

falls to the bottom of the

41:17

harbour, and they put

41:19

a significant oxygen demand onto the

41:21

system. The scale of fish farming

41:23

in Macquarie Harbour, if you translate it into

41:25

the sewage produced by a city of a

41:28

given size, would be somewhere in the order

41:30

of a million people. That is

41:32

a lot of waste going into a

41:34

system. That's every year, and

41:36

that's at the reduced amount now. It

41:39

used to be more than double that. Correct. What

41:42

do you think should happen now? Our

41:44

feeling is that the scale of farming

41:46

is too big for the harbour. We

41:49

believe that it should be reduced, that

41:51

the pens need to be removed from

41:53

the harbour, and the harbour fallowed until

41:55

there's clear evidence that a recovery is

41:57

in progress. That is the

41:59

fastest. in the most direct way to

42:01

achieve that. But to

42:04

follow that system would have

42:06

huge social and economic ramifications

42:08

for this small coastal community.

42:10

So there are ramifications and

42:12

those obviously need to be

42:14

addressed. We feel the time

42:16

has really come that a

42:19

transition strategy needs to be

42:21

clearly articulated and

42:23

implemented for the community there.

42:26

There's many industries around the world that

42:28

are no longer sustainable and

42:30

transition strategies are needed to move

42:33

those to new and better jobs

42:35

actually. But what would that look

42:37

like? You could

42:39

trial land-based salmon farming. There's

42:41

a huge amount of investment

42:43

in that globally. You could

42:45

consider abalone farming on land,

42:47

seaweed, rock lobster. There's a

42:49

whole range of different species

42:51

that could make use of

42:53

the relatively cool clean water

42:55

offshore instead of putting the

42:57

waste into a very restricted

42:59

oxygen-poor system such as Macquarie

43:01

Harbour. So you're basically suggesting

43:04

continue with aquaculture but do it

43:06

on land near Macquarie Harbour. There's

43:08

certainly a solution that should be looked at

43:10

and promoted both at the state level and

43:12

the national level. When the

43:15

IMAS scientists released their new

43:17

information on the skate last

43:19

year, three environmental groups independently

43:21

wrote to Federal Environment Minister Tanya

43:23

Plibersek to trigger a review

43:25

of the federal government's 2012

43:28

decision. Eloise Carr

43:30

is the Tasmanian Director of the

43:32

Australia Institute. There's this

43:35

opportunity in our national environmental

43:37

law where when a decision

43:39

has been made, if

43:42

new evidence becomes available about

43:45

the impacts of an activity

43:47

on a matter of national

43:49

environmental significance, that

43:51

you can request that that

43:53

decision be reviewed. What

43:55

response or what outcome are you seeking

43:57

from the Federal Minister? Salmon

44:00

farming is clearly having an unacceptable

44:02

impact on a matter of

44:04

environmental significance, and

44:06

the Federal Environment Minister should make

44:08

a decision that recognises that. As

44:11

the Conservation Advice of the Federal

44:14

Government says, salmon

44:16

farming should either be eliminated

44:18

or significantly reduced in Macquarie

44:20

Harbour. The Conservation

44:23

Advice from the Government

44:25

recommended removing salmon and or

44:28

technological solution like the

44:30

Macquarie Harbour oxygenation project.

44:33

Isn't the Australia Institute being a

44:35

little bit misleading in suggesting that

44:37

removing salmon is the only option?

44:40

Not at all. I think you're

44:42

referring to the summary. When you

44:44

actually read the details of the

44:47

Conservation Advice of the Federal Government,

44:49

it is crystal clear that

44:52

salmon farming is having the most

44:54

impact on the Morjean skate and

44:56

the water quality, the dissolved oxygen

44:58

levels in Macquarie Harbour. It's

45:01

been identified in the threats

45:03

analysis as having a

45:06

likely catastrophic impact on the

45:08

Morjean skate, and it's clearly

45:10

identified as the number one

45:12

priority action which is marked

45:15

urgent before this summer to

45:17

either eliminate or significantly reduce

45:19

biomass of fish farming in

45:21

the harbour. And

45:24

of hydroelectric flows is also

45:26

identified as a threat that's

45:28

potentially catastrophic. It's clearly

45:30

identified as a secondary threat as

45:33

is gill netting and climate

45:35

change. And the primary

45:37

threat is salmon farming. So

45:40

you want that to end immediately? We

45:43

think that's the only way for the Morjean

45:45

skate to have a chance of surviving. Two

45:48

of the four Morjean skate that were

45:50

taken from the wild into the captive

45:52

breeding program have died. So

45:54

that means clearly we have to try

45:56

harder to actually keep the species going

45:58

in its natural habitat. and

46:01

Macquarie Harbour is the only natural habitat

46:03

for the skate. 7

46:06

Tasmania's Luke Martin is comfortable

46:08

with the current level of 9,500 tonnes. We're

46:11

not going to give a sacrifice to the industry

46:13

on the basis of pressure from activist groups. What

46:15

we'll do is follow the science, follow our regulators,

46:17

but also try and actually be constructive and make

46:19

a positive contribution to securing the underlying issue, which

46:22

is the harbour's environment and the scale of the

46:24

skate. The industry has put now

46:26

around $6 million into this oxygenation project that's

46:29

been done very quickly. There's no other

46:31

industry and there's no government agency that's done

46:33

that as quickly as we have. So it's a pretty

46:35

clear indication that we want to be there for the

46:37

whole. We want to support the harbour. We recognise we're

46:39

having an impact on it. But we also believe

46:42

that the appropriate way here is to work through those challenges, not

46:44

just kick us out. Jeff

46:46

Ross from IMS is leading

46:48

the Macquarie Harbour oxygenation project.

46:51

The system will be powered by diesel,

46:54

run from a barge owned by Tassale, stationed

46:57

near a human aquaculture lease

47:00

with Petuna running the day-to-day

47:02

operations. The system will

47:04

draw up water from the lower levels of the

47:06

harbour, inject it

47:08

with oxygen nanobubbles and return it

47:11

to the same depth. Once

47:14

in full swing, the barge will

47:16

have the capacity to inject 5 tonnes

47:18

of oxygen per day. Our

47:21

estimates would put salmon farming

47:23

waste, contributes in the

47:25

order of 10 to 20 tonnes per

47:28

day of oxygen demand in that

47:30

water column up above the respiration. I guess

47:32

that's re-oxygenated that water column, but down below

47:34

it's about 10 to 20 tonnes of

47:38

the 4,000 tonnes around about that's sitting

47:40

there. So it's a relatively

47:42

small amount, but it's there every

47:44

day. If there's nothing

47:46

putting oxygen in the bank for a year,

47:49

then salmon farming becomes really quite

47:51

significant. But if the natural environment

47:53

is putting oxygen in, then it

47:55

can dwarf the consumption of oxygen.

47:57

So for instance, this summer... We've

48:00

had quite a big recharge which is likely to have

48:02

put in 500 to 1000 tonnes in the last month

48:07

or two. So how

48:09

significant farming is depends on

48:12

how much the natural environment is putting in at

48:14

the same time. So I suppose

48:16

it comes down to limits. Everything

48:18

can be hunky-dory and then all of

48:20

a sudden you're in a

48:23

restricted environmental situation and that's when

48:25

the damage can be done in

48:27

terms of losses of animals like

48:29

skate or other marine creatures.

48:31

Absolutely. So the industry are fully

48:33

acknowledging their contribution to the oxygen

48:35

demand and that contribution to the

48:38

decline. What the industry can

48:40

be doing is be responsible for their

48:42

own contribution. So this oxygen

48:44

trial is about seeing if this

48:46

technique that's been proven overseas can

48:49

offset that demand that

48:51

salmon aquaculture has. The

48:54

Independent Science Council is not

48:56

convinced. Christine Kokenau. We

48:59

have some real concerns about that because

49:01

it is at a scale that is

49:03

untested globally. I mean Macquarie Harbour is

49:05

a huge system compared to the other

49:08

examples that have been given. It

49:10

has much lower oxygen levels over a

49:12

much larger volume of water. For example

49:14

the Swan Canning which is being held

49:17

up as the example is

49:19

probably about 1 eighth

49:21

hundredth of the size of Macquarie Harbour

49:23

in terms of the amount of oxygen

49:26

that needs to be injected and the area

49:28

that needs to be treated. By

49:30

comparison Macquarie Harbour is just

49:32

a completely different scale. Similarly

49:35

Savannah River another very

49:38

large reoxygenation project in the

49:40

United States. Possibly about

49:42

a third the size of Macquarie Harbour in terms

49:44

of volume. That project

49:46

took over 10 years to design

49:48

and implement and the cost is

49:50

extremely high. I think it's over

49:52

150 million dollars to

49:54

construct that project and somewhere in the

49:57

order of 3 to 5 million dollars

49:59

a year. to run it. So the

50:01

costs are also questioned even if it could

50:03

be done and there's a lot of risks

50:05

that need to be addressed around is it

50:08

even feasible but even if it could be implemented

50:10

who would pay for it how much would it cost?

50:13

One frustrating thing we found is

50:15

very very little public information it's

50:17

really difficult to get our heads

50:19

around is this an offset or

50:21

is this a remediation project? Is

50:24

the goal to save the Magian skate

50:26

or are there other purposes as well?

50:28

You're suggesting we should remove the

50:31

salmon straight away others say let's

50:33

wait and see how well the

50:35

Macquarie Harbour oxygenation project goes and

50:38

its potential before we

50:40

deconstruct everything. I think

50:42

the issue with wading is that

50:45

even if the deoxygenation project or

50:47

the modification of flows or a lot

50:49

of these things are successful in

50:51

the long term they will take time to set

50:53

up. Getting the oxygen

50:55

into the water in a short period

50:58

of time to a level that's really

51:00

going to make a difference I think

51:02

is very debatable. The salmon is the

51:04

most direct way to remove oxygen demand

51:06

in the short term. These

51:08

other projects they might accelerate that response

51:10

in the system which would be great

51:13

the faster we can get oxygen back

51:15

into the system the better but

51:17

I think to hold out the hope of

51:20

we're going to solve this problem with an

51:22

oxygenation project is extremely

51:25

optimistic. Jeff Ross

51:27

from IMAS says the

51:29

oxygenation project is taking a

51:31

very considered approach. Macquarie

51:33

Harbour is unique so we've been doing

51:35

modelling and we're satisfied that the saturated

51:38

water will stay at depth and it'll

51:40

spread and dilute fairly quickly. How

51:42

much distance do you think that oxygen

51:44

can travel? We're expecting from this plant

51:47

that we may be able to detect it for

51:49

a couple of kilometers in the main current directions.

51:51

We're doing a trial we're going to do it

51:53

in baby steps And we're going

51:55

to measure the ecosystem response so we're going

51:57

to look at the metals to make sure.

52:00

The not coming out. a solution we

52:02

gonna look at nutrients, were gonna look

52:04

at the oxygen levels in the salinity

52:06

levels, fish, fetal ice ice and system.

52:08

make sure that it's safe and efficient.

52:11

and then we'll slowly ramp up that

52:13

oxygen ice and traub so that the

52:15

trial itself, that pods and the system

52:17

that the industry of thoughts has the

52:19

capacity easily that up to five tons

52:22

per die. And of course you can

52:24

add more boxes or more points. But

52:26

first we we mourn or understand that

52:28

it's safe. We want. To understand that

52:30

it's working in the oxygen ice and is

52:33

dying. It dips And then we also want

52:35

to understand what's the most effective way of

52:37

adding instead assistance. Do we have one big

52:39

system when we pump it from my Tyson?

52:42

Or do we have lots of little systems

52:44

around The have a. Disease

52:53

the most endangered charter a species and

52:55

on the world and reality is that

52:57

environmental degradation and coastal area is something

53:00

that is happening not only Mccourt Harbor

53:02

but in several areas so we see

53:04

it as second or in a coal

53:06

mine for a lot more. It really

53:09

solidify the litmus test towards our ability

53:11

to say this is challenges of environmental

53:13

degradation and save this incredibly unique species

53:15

because this is the first of many.

53:18

Unfortunately with changing climate conditions and continues

53:20

human activity in coastal areas that are

53:22

coming so. This is a small

53:24

semi close systems so we have a bit

53:27

more control over conditions. And yes, it would

53:29

be a good first test about what we

53:31

can do when we come to their to

53:33

work and whether we can actually stay boss

53:36

Things like extinction. That.

53:42

Report by Alexander The Blast in Tasmania

53:44

production for the side so by David

53:47

Fisher and next week the to play

53:49

as meeting just ended in Denver, Colorado

53:51

and A Neutron Star no less. I'm

53:54

Robin Williams. You've

53:57

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