0:01

In case we haven't met, I'm Dino Colombo.

0:04

I represent people hurt by a truck. It's

0:06

what we do every day. I've

0:08

seen truck accidents devastate families, but

0:11

we can help. Hurt by a

0:13

truck? Call Colombo Law. This

0:15

is Spacetime Series 27 Episode 61 for broadcast on

0:17

the 20th of May, 2024. Coming

0:22

up on Spacetime. A spectacular

0:24

solar storm stuns the world. Unusual

0:27

activity in Earth's magneto tail.

0:30

And scanning the skies for neutrinos

0:32

from deep under the sea. All

0:35

that and more coming up on

0:37

Spacetime. Welcome

0:40

to Spacetime with Stuart Gary.

0:59

The sun has produced its biggest

1:01

solar flare in nearly two decades.

1:04

The massive 8.7 class explosion

1:06

rounded off more than a

1:08

week of spectacular geomagnetic storms

1:10

which pummeled the Earth and

1:12

created dazzling northern and southern

1:14

aurora lights powerful enough to

1:16

reach middle attitude skies normally

1:18

unaccustomed to seeing such spectacles.

1:21

NASA's Solar Dynamics Observatory captured the

1:23

bright blast, which was the strongest

1:25

solar flare since 2005 and the

1:27

biggest during the sun's current 11-year

1:30

solar cycle. The

1:32

event has been classified as an

1:34

extreme geomagnetic storm, the first since

1:36

the Halloween storms of October 2003

1:38

which caused blackouts in Sweden and

1:41

damaged power infrastructure in South Africa.

1:44

The solar cycle is a nearly periodic

1:46

11-year change in the sun's activity measured

1:48

in terms of variations in the number

1:50

of observed sunspots on the sun's surface.

1:54

Over the period of the solar cycle,

1:56

levels of solar radiation and ejection of

1:58

solar material the number size of

2:00

sunspots, solar flares and coronal loops

2:02

all exhibit a synchronized fluctuation from

2:04

a period of minimum activity known

2:06

as solar minimum to a period

2:08

of maximum activity known as solar

2:10

maxima or solar max for short

2:12

and then back to a period

2:14

of minimum activity again. The

2:17

sun's magnetic field flips polarity during

2:19

each solar cycle, with the star's

2:21

magnetic north pole becoming south and

2:23

its south pole becoming north. This

2:26

flip occurs at solar max. After

2:30

two solar cycles, the sun's magnetic field

2:32

returns to its original state, completing what's

2:34

known as a hail cycle. The

2:36

current solar cycle, number 25, began

2:38

back in December 2019 and appears

2:41

to be happening unusually quickly with

2:43

solar max likely to occur a

2:45

year earlier than expected. The

2:47

good news is the powerful X8.7 class

2:50

solar flare which erupted last week was

2:52

facing away from the Earth as sunspots

2:54

which spawned it were rotating over the

2:57

sun's western or right hand limb. The

3:00

flare was caused by a cluster of

3:02

sunspots known as active region 3664. The

3:06

cluster was around 17 times as

3:08

wide as the planet Earth itself and

3:10

it was by far the largest and

3:12

most complex solar sunspot region observed during

3:15

the current cycle. Starting

3:17

around May the 8th, active region 3664

3:19

sent at least seven solar flares and

3:22

coronal mass ejections racing towards the Earth,

3:24

often reaching speeds of up to 1800

3:27

km per second and they triggered

3:29

the most intense geomagnetic storms or

3:32

space weather events of the current

3:34

solar cycle. Space

3:36

weather is a sudden flood of

3:38

energy and ionized particles such as

3:40

protons, electrons and atomic nuclei triggered

3:42

by powerful eruptions of solar flares

3:45

and coronal mass ejections on the

3:47

sun's surface. Solar

3:49

flares are explosions of energy caused by

3:51

the sudden snapping of tangled and twisted

3:54

magnetic field lines. These

3:56

are known as flax ropes and they emanate

3:58

from sunspots on the solar surface. Sunspots

4:01

are cooler regions on the sun's

4:03

surface that appear darker than surrounding

4:05

areas. That's because the magnetic

4:07

field lines reaching out into space from deep

4:09

inside the sun at these places prevents some

4:11

of the heat from within the sun from

4:13

reaching the surface. Sunspots

4:16

usually appear in pairs of opposite

4:18

magnetic polarity. The number

4:20

varies according to the 11 year solar

4:22

cycle. There are very few

4:25

and sometimes none at all during solar

4:27

minimum and they reach the crescendo at

4:29

solar max. Individual sunspots

4:31

or groups of sunspots can last anywhere

4:33

from a few days to several months

4:36

but they will eventually decay. Sunspots

4:39

expand and contract as they move across the

4:41

surface of the sun with diameters ranging from

4:43

16 to 160,000 km. Oh

4:48

what's behind them? Well different latitudes

4:51

of the sun rotate at different

4:53

rates, causing these magnetic field lines

4:55

to become tangled and twisted, eventually

4:57

snapping and then realigning through magnetic

4:59

reconnection. And that produces

5:01

secondary phenomena such as coronal loops, hominences

5:04

and eruptions of electromagnetic energy which if

5:06

facing the Earth enrich the planet in

5:08

just 8.3 minutes. If

5:11

the solar flares are powerful enough, they'll

5:14

also drag billions of tons of coronal

5:16

plasma and embedded magnetic field frozen as

5:18

flux with them, exploding out into space

5:20

at speeds of up to 3000 km

5:23

per second, which if facing the Earth

5:25

will reach our planet in just 15

5:28

to 18 hours. When these

5:30

geomagnetic storms reach the Earth, the flux

5:32

of ionized particles slam into our planet's

5:35

magnetosphere and they're then guided by the

5:37

planet's magnetic field lines through the ionosphere,

5:39

a region already filled with charged particles

5:41

and then down towards the north and

5:44

south magnetic poles. Now

5:46

as these charged streams of plasma

5:48

travel through the Earth's upper atmosphere,

5:50

they collide with oxygen and nitrogen

5:52

atoms and molecules, causing them to

5:54

excite and emit photons, giving off

5:56

a glow and producing colorful, kern-like

5:58

displays known as the northern and

6:00

southern lights, the aurora borealis

6:03

and aurora australis. The

6:05

colours being emitted by these lights

6:07

depends on which particles are being

6:10

ionised. Redish brown glows are

6:12

caused by the collision of particles with

6:14

single oxygen atoms in the Earth's upper

6:16

atmosphere, usually above 300 kilometres. Though

6:19

down, a green hue is created by

6:21

single oxygen atoms down to altitudes of

6:23

around 100 kilometres.

6:26

The light of the light is then turned to white

6:28

and shallow beige when nitrogen is mixed in with oxygen.

6:31

Aurora also exhibit a blue, red or

6:34

even purple glow in the lower atmosphere

6:36

caused by the excitation of molecular nitrogen

6:38

below 100 kilometres. However,

6:41

as well as the spectacular aurora

6:43

light shows, these honey-charts particles can

6:45

also cause a lot of damage,

6:47

even destroying spacecraft by shorting out

6:50

electronics and damaging circuits. They

6:52

also cause the Earth's atmosphere to

6:54

expand and contract, wobbling like jello,

6:56

and that increases atmospheric drag on

6:58

orbiting spacecraft, resulting in premature orbital

7:00

decay and the need to use

7:02

up more fuel in order to

7:04

maintain an operational orbit. Worse

7:07

still, space weather increases the level

7:09

of radiation exposure astronauts experience affecting

7:11

their health. On the

7:14

ground, these solar storms can overload

7:16

power lines, blowing transformers and causing

7:19

widespread blackouts. In 1989,

7:21

one such geomagnetic storm blew out

7:23

a whole bunch of transformers causing

7:25

massive blackouts across eastern North America.

7:29

Geomagnetic storms also affect communications

7:31

and navigation satellites. But

7:33

satellite operators, electrical grid managers and

7:35

engineers who maintain crucial technological infrastructure

7:38

say while they're still assessing the

7:40

impact of this historic event, most

7:42

major systems seem to have weathered

7:44

the blast okay. Although New Zealand's

7:46

electrical transmission services did temporarily turn

7:49

off some circuits around the country

7:51

to prevent equipment damage. As

7:53

a precaution NASA temporarily stopped gathering

7:55

astronomical data from its Chandra X-ray

7:58

Observatory and stirred it's insta- instruments

8:00

in order to protect them from the radiation

8:02

blasts. And the agency's

8:04

ICESat-2 spacecraft suddenly shut down

8:06

when it experienced unexpected rotation

8:08

during the storm, probably caused

8:11

by increased atmospheric drag. The

8:13

agency says however there was no

8:15

threat to crew aboard the International

8:17

Space Station and Beijing says their

8:19

Tiangong space station also remained operational.

8:22

The concerns like that were far from

8:24

the mind to the general public, with

8:27

the northern and southern lights at their

8:29

best and social media being flooded with

8:31

stunning images. Normally restricted

8:33

to polar regions and higher latitudes, the

8:35

auroral light show was visible all the

8:37

way south to Mexico in the Bahamas

8:40

and north as far as Tasmania, Melbourne,

8:42

Perth and Adelaide. Now the

8:44

cause of all this, active region 3664

8:46

has now rotated off the side of

8:48

the sun scene from Earth and entered

8:50

the field of view of the European

8:52

Space Agency's solar orbiter which is in

8:54

the middle of a series of dives

8:56

through the sun's outer atmosphere and will

8:59

undoubtedly provide a new perspective on all

9:01

the activity. And NASA's Parker

9:03

Solar Probe spacecraft, which is currently at the

9:05

outer part of its looping orbit around the

9:07

sun, will also be able to provide some

9:09

unique data. And it doesn't

9:12

end there. For two of NASA's

9:14

Mars spacecraft, the solar storm provides

9:16

an unprecedented opportunity to study how

9:18

intense solar activity hits the Red

9:20

Planet. NASA's Mars Atmosphere

9:22

and Volatile Evolution spacecraft, MAVEN,

9:24

monitored the geomagnetic storm's effects

9:26

on the Red Planet's atmosphere

9:28

while the agency's Curiosity Rovering

9:31

Gail Crater studied those same

9:33

effects from the ground. For

9:35

the record, the most powerful geomagnetic

9:37

storm in recorded history was the

9:39

Carrington Event, named after British astronomer

9:42

Richard Carrington. It peaked around

9:44

the 1st and 2nd of September in 1859, during what

9:46

was Solar Cycle X. It

9:50

created strong auroral displays that were

9:52

reported globally and caused sparking and

9:55

even fires at multiple telegraph stations.

9:58

A geomagnetic storm of that magnitude.

10:00

due to current today would cause

10:02

widespread electrical disruptions, power blackouts and

10:04

other damage due to extended outages

10:06

of the electrical grid. But

10:09

it's not all over yet folks. We're

10:11

getting our first glimpse of the new

10:13

active sunspot region, this one's been named

10:16

3685 which is now a rotating interview around

10:19

the eastern or left hand limb of the

10:21

sun. And it's already erupted in major X

10:23

class solar flares, including one X 2.99 event.

10:28

It certainly looks like the upcoming solar

10:30

max will be really interesting. This

10:33

is space time. Still

10:35

to come unusual activity in the

10:37

Earth's magneto tail and scanning the

10:39

skies for neutrinos from deep under

10:41

the sea. All that and

10:44

more still to come on space time. Astronomers

11:02

have detected an unusual event in

11:04

Earth's magneto tail, the elongated portion

11:06

of the planet's magnetosphere trailing away

11:09

from the sun. The

11:11

data from NASA's magnetospheric multiscale mission

11:13

spacecraft are showing fleeting disturbances in

11:15

the magneto tail known as substorms

11:18

that are releasing energy and triggering

11:20

a raw activity. Since

11:22

their launch in 2015, the fourth

11:24

spacecraft have been surveying the magneto

11:26

pores, the boundary between the magnetosphere

11:28

and surrounding plasma. They

11:31

are looking for signs of magnetic

11:33

reconnection, which happens when magnetic field

11:35

lines converge, break apart and then

11:37

reconnect explosively, converting magnetic energy into

11:40

heating kinetic energy. In 2017,

11:43

they observed signs of magnetic reconnection

11:45

in the magneto tail, but not

11:47

the normal signs of the substorm

11:49

that accompany reconnection, such as strong

11:51

electrical currents and perturbations in the

11:53

magnetic field. One of the

11:55

scientists involved in the study, A.D. Marshall from

11:58

the Southwest Research the

12:00

local physics observed by the probes affects the

12:02

entire global magnetosphere. By

12:06

comparing that event to more typical substorms,

12:08

scientists are striving to improve their understanding

12:10

of what causes a substorm and the

12:12

relationship between substorms and magnetic reconnection. During

12:17

this year-long project, scientists

12:19

will compare in-situ measurements of magnetic reconnection affecting

12:21

local fields and particles to global magnetosphere reconstructions

12:24

created by NASA's Goddard

12:28

Space Flight Center using space

12:31

weather computer modeling. Marshall

12:33

says it's possible significant differences

12:36

exist between the global magneto-tail

12:38

convection patterns for substorms and

12:40

non-substorm tail reconnection. Researchers

12:43

haven't yet looked at the movement of

12:45

magnetic field lines on a global scale.

12:47

So it could be that this unusual

12:49

substorm was a very localized occurrence that

12:52

spacecraft just happened to be lucky enough

12:54

to observe. On the other

12:56

hand, if not, it could completely

12:58

reshape science's understanding of the relationship

13:01

between tail side magnetic reconnection and

13:03

substorms. Needless to

13:05

say, we'll keep you informed. This

13:08

is space time. Still

13:10

to come, scanning the skies for neutrinos

13:12

from deep under the sea. And

13:15

later in the science report, new observations have

13:17

now confirmed that April 2024 was the hottest

13:21

month on planet Earth ever recorded.

13:23

All that and more still to come of

13:26

space time. China

13:43

has started construction of the Deep Sea

13:45

Neutrino Telescope in the western Pacific. The

13:48

tropical Deep Sea Neutrino Telescope, or

13:50

TRIDANS, will search for, detect and

13:52

analyze neutrinos in order to study

13:55

the origins of cosmic rays and

13:57

explore the extreme universe. Neutrinos

14:00

are elementary subatomic particles. They

14:03

are generated through radioactive decay

14:05

in stars, in supernovae, in

14:08

nuclear explosions, in particle accelerators,

14:10

and in atomic reactors. The

14:12

neutrinos are so named because it is electrically

14:14

neutral, and because its rest mass is so

14:16

small it was long thought to be zero.

14:20

Neutrinos are the most common form of matter

14:22

in the universe, and having almost no mass,

14:24

they are capable of being accelerated to almost

14:26

the speed of light. They

14:28

come in three known types

14:30

of flavors, electron neutrinos, muon

14:33

neutrinos, and tau neutrinos, each

14:35

with its own specific properties.

14:37

Now confusingly, the three flavors of

14:39

neutrinos don't line up with the

14:42

three mass species. It

14:44

seems each of the three flavors is made

14:46

up of a quantum mixture of the three

14:48

mass species, so for example a particular tau

14:50

neutrino with bits of all three mass species

14:53

in it. These different

14:55

mass species allow the neutrino to

14:57

oscillate between the three flavors. For

14:59

example, an electron neutrino produced in let's

15:02

say a beta decay reaction could end

15:04

up interacting with the distant detector as

15:06

the muon or tau neutrino. Although

15:09

they have no electrical charge,

15:11

neutrinos do have their own

15:13

corresponding antimatter counterparts identified by

15:15

the opposite chirality or handedness.

15:19

Neutrinos interact with other matter only through

15:21

gravity and the weak nuclear force. In

15:23

fact, they're so weakly interactive that several

15:25

trillion are passing through you every second

15:27

without you even realizing it. China's

15:30

neutrino observatory is being built on a deep

15:32

sea plane, some 3.5 kilometers below the

15:35

surface. The detector will comprise

15:37

1200 vertical

15:39

strings or cables, each 700 meters long

15:41

and spaced between 70

15:44

and 100 meters apart. Each

15:47

string will carry 20 high-resolution digital

15:49

optical detector modules. Spanning

15:52

around 4 kilometers and covering some 12

15:54

square kilometers, the array will monitor around

15:56

8 cubic kilometers of sea water. Looking

15:58

for some more? high energy neutrino

16:01

interactions. It will be

16:03

the fourth neutrino array of this type. The

16:06

others include the famous Ice Cube

16:08

Observatory on Antarctica which is the

16:10

world's leading neutrino telescope, the Bical

16:13

GVD Observatory on Lake Bical, and

16:15

the cubic kilometre neutrino telescope or

16:17

KM3 net located from 3.5 kilometres

16:19

below the surface in the Mediterranean

16:22

Sea at three locations off the

16:24

coast of Sicily, France and Greece.

16:27

The cubic kilometre neutrino telescope is

16:29

still under construction and it includes

16:31

the astroparticle research with Cosmics in

16:33

the Abyss or Arcut telescope which

16:36

will search for neutrinos from distant

16:38

astrophysical sources such as supernovae, gamma

16:40

ray bursts and colliding stars and

16:42

the oscillation research with Cosmics in

16:45

the Abyss or Arcut telescope which

16:47

is studying neutrino properties exploiting neutrinos

16:49

generated in its atmosphere. A

16:52

raise of thousands of optical photomodipy

16:54

sensors will detect the faint light

16:56

in the deep sea from charged

16:58

particles originating from collisions between neutrinos

17:01

and the Earth. The facility

17:03

will also include instrumentation for Earth and

17:05

sea sciences for long term and online

17:07

monitoring of the deep sea environment and

17:09

of the sea floor. Once

17:12

complete, the Arca detector will form an array

17:14

of more than 200 detection units. Each

17:17

of these 700 metre long cables will hold 18

17:20

modules equipped with ultra-sensitive light detectors

17:22

that register the faint flashes of

17:25

Sherenkov radiation generated by neutrino interactions

17:27

in the pitch black abyss of

17:29

the Mediterranean Sea. The

17:31

position and direction of the optical modules

17:33

and the time of arrival of the

17:36

light on the photomodiply is inside as

17:38

recorded and the trajectories of the particles

17:40

then reconstructed from these measurements. The

17:43

entire cubic kilometre neutrino telescope project

17:45

should be completed and fully operational

17:47

by 2026, occupying

17:49

more than a cubic kilometre of water

17:52

comprising hundreds of vertical detection lines anchored

17:54

to the seabed and held in place

17:56

by buoys. Nancy

18:00

James from Curtin University and the

18:02

International Centre for Radio Astronomy Research

18:04

says such a huge volume of

18:06

water was required to surround the

18:08

instruments because neutrinos would otherwise be

18:10

extremely difficult to detect. James

18:13

says the underwater telescope is bombarded by

18:15

millions of different particles, but only neutrinos

18:17

can pass through the Earth to reach

18:19

the detector from below, so unlike

18:22

normal telescopes which look upwards into

18:24

the skies, this facility looks downwards

18:26

towards the Earth. Thereby,

18:28

seeing the same skies as viewed

18:31

by upwards facing telescopes in Australia.

18:33

The particles that came through

18:35

that are detecting neutrinos, they interact very

18:37

rarely and we expect came through that

18:39

to only detect maybe of order dozens

18:41

per year. However, there's also particles from

18:43

these cosmic ray interactions that hit the

18:45

top of the atmosphere muons and come

18:47

down. So what this means is that

18:49

the detector is saturated by about a

18:51

million muon events a day coming down

18:53

from above. However, only neutrinos can actually

18:55

make it up from under the detector.

18:58

So the best way of saying, okay,

19:00

we detected this particle, was it a

19:03

neutrino or was it something else? Is

19:06

to look for particles coming up

19:08

from underneath the detector, coming up through the

19:10

Earth at which point you can say, well,

19:12

the only thing that could have possibly made

19:14

it through the whole Earth through the detector

19:16

was a neutrino. So what this means is

19:18

that neutrino telescopes mostly look downwards through the

19:20

Earth as opposed to normal telescopes when you

19:22

point them up at the sky above you.

19:24

And so the sky, the region of the

19:27

universe that came through that we'll be studying

19:29

is the region of the universe that's visible

19:31

from normal telescopes on the opposite side of

19:33

the world, that is to say Australia, which

19:35

means that the sky that Australian telescopes are

19:37

viewing is exactly the same sky that

19:39

came through that's viewing all the time.

19:41

Now neutrinos are the most common type

19:44

of massive, I say massive particle in

19:46

the universe, particle that has mass, but

19:48

they almost never interact with things. So

19:50

we have something like 10

19:52

to the 12 passing through us

19:54

every second of that order from the sun. So

19:57

the neutrinos are produced in nuclear reactions. The ones

19:59

where? kind of look for, are produced by

20:01

high opposite

20:19

where Australia is. Is that deliberate

20:23

or is that just coincidence? It's a coincidence. So the reason

20:25

it's there is simply because it's a collaboration of European people

20:30

want to build an instrument. It's easier to do

20:32

it nearby. And the main constraint you need is

20:34

to get this thing down deep, right? You need

20:36

it to be deep down in the water for

20:39

two reasons. One, so it's dark. So when you

20:41

do sort of an estimate of the amount of

20:43

light that you get detected, what happens is a

20:45

neutrino, if it does interact, will produce a burst

20:47

of light and that light is extremely faint. So

20:50

you might only detect maybe a dozen photons from

20:52

that collision, which is about the amount of light

20:54

that you get in one second from my light

20:56

globe here in my office that you would see.

21:00

So it's not very much light. So you

21:02

need it to be in a really dark

21:04

place and you don't actually get it to

21:06

be dark enough unless you're more than a

21:08

kilometre under the surface of the water. The

21:10

other reason is that these cosmic rays I

21:12

mentioned earlier, these high energy particles from

21:14

space, they're hitting the top of our

21:16

atmosphere all the time. And they produce

21:18

more particles that then sort of rain

21:20

down on us at sea level. And

21:22

some of these particles called muons can

21:24

actually go through kilometers of stuff. They

21:26

actually don't get stopped very easily at

21:28

all. And so what you

21:30

want to do is shield yourself from as

21:33

many of these muons as possible by going

21:35

deeper and deeper. Now you can't shield yourself

21:37

from all of them. So K-M3Net will detect

21:39

something like a million of these muons a

21:42

day, but nonetheless it's much easier to do

21:44

at the surface. So the reason it's being

21:46

built at the bottom of the Mediterranean is

21:48

that there's some sufficiently deep places there to

21:50

do this experiment. Is there a reason why

21:52

you've chosen liquid water rather than solid water

21:54

such as the South Pole Neutrona detector? Yeah,

21:56

exactly. So I think... Cube

22:00

is the name of the instrument you're from

22:19

the site ever. But the main

22:21

reason is

22:24

that it turns out that water is an excellent medium to do this

22:26

in. It absorbs more

22:28

light than ice. So you want to detect

22:30

light from these faint neutrinos but light gets

22:32

absorbed in water with a length of scale

22:34

of say 50 meters whereas in ice a

22:36

photon might bounce around for 200 meters before

22:38

it gets absorbed. However if you ever like

22:40

stand on top of the snow and look

22:43

into ice versus stand on top of water

22:45

and look down you see further into water

22:47

right and this is because water

22:49

doesn't scatter light as much. So what

22:52

this means is when when a neutrino

22:54

interacts it emits the light in a

22:56

characteristic cone shape but it comes out

22:58

with a cone with an opening angle

23:00

of about 30 degrees. This is Charonkop

23:02

radiation. That blue Charonkop radiation light. It's

23:04

exactly the kind of light that we're

23:06

detecting. This light comes from these particles

23:08

from high energy particles that

23:10

have been in this case emitted by

23:12

radioactivity and Km3 net emitted from the interaction

23:15

neutrino and because they're going really fast

23:17

through the water they emit a shockwave

23:19

just like a supersonic jet emits

23:22

a shockwave and that shockwave comes across

23:24

in blue light whereas a supersonic jet

23:26

shockwave comes across in terms of a

23:28

sharp crack of sound. There's new science

23:31

to be had here. Yes exactly.

23:33

So the key part about Km3 net is that

23:35

it's really going for a high resolution detector. At

23:38

the end of the day it's going

23:40

to act like a telescope. You're going to detect

23:42

neutrinos. You get some idea of how much energy

23:44

they had but you want to find out where

23:47

they're coming from right. This is a big mystery

23:49

we're trying to solve. What's producing high energy

23:51

neutrinos in the universe? There's a lot of

23:53

ideas but we don't know the answer. So

23:55

in astronomy you take a telescope, you point

23:57

it somewhere and you see what you see.

24:00

right? What's producing light? Oh look at

24:02

the star. However the angular resolution of

24:04

ice cube, I mean it's not bad

24:07

but it's not that great when typically

24:09

maybe of order a degree or so

24:11

for the best events or thereabouts and

24:14

the universe is big. So when you point

24:16

back and say oh there's a neutrino that

24:19

came from this direction, what's there? The answer

24:21

is all sorts of things because you can't

24:23

tell with enough precision where the neutrino came

24:25

from. So it came through and it's going

24:27

to have an angular resolution of maybe five

24:30

to ten times an improvement over ice cube

24:32

and the idea being that you can really

24:34

detect exactly where the neutrinos are coming from

24:36

and be more definite about their sources. Better

24:39

crosshairs to find your target. Exactly. I'm right

24:41

in thinking neutrinos are the most common substance

24:43

to the universe other than photons. Well

24:45

there's also dark matter particles. That's

24:48

what it's going to come to next and it's possible

24:52

that neutrinos are also being considered

24:54

as some types

24:57

of neutrinos that species not yet actually

24:59

discovered are being considered as a possible

25:01

candidate for dark matter. Yeah that's true.

25:03

So basically there's three, let's call them

25:05

normal types of neutrinos or flavours of

25:08

neutrinos that are part of the standard

25:10

model of particle physics. So we know

25:12

that these normal neutrinos can't be dark

25:14

matter, they're not a dark matter candidate. However

25:16

there is quite a few different theories of what

25:19

we could be on the standard model of

25:21

particle physics. For instance there's something called supersymmetry that

25:23

predicts that for every normal particle we see

25:25

there's something called a supersymmetric partner of that particle.

25:27

I won't go into the exact details of

25:29

this mostly because I am not an expert on

25:31

it and anything I say will probably be

25:33

wrong. However the supersymmetric

25:35

partner of the neutrino or neutrino

25:38

which is called is quite likely

25:40

the lightest supersymmetric particle and therefore

25:43

the easiest to detect. So one

25:45

of the goals of KM3Net, so mostly

25:47

what we're doing is detecting high-energy astrophysical

25:49

neutrinos from these sources that at a

25:52

technical the Arca detector will be detecting.

25:54

There's another component to KM3Net which is

25:56

called Orca which will be a similar

25:59

number of photon detectors but compacted

26:01

into a smaller sequence

26:19

or they don't have to do a

26:21

certain sequence however there's a certain probability.

26:23

Yeah so there's a

26:30

certain flavor and then has a certain energy

26:35

what the probability of it is to mix into

26:37

the other neutrino flavors and this is dependent upon

26:40

how far it travels and what its energy is

26:42

and what its initial flavor is. One thing that's

26:44

worthwhile noting though is that we

26:47

know there's a three flavors of neutrinos but we

26:49

don't know what the heaviest ones are, right? This is

26:51

something called the neutrino mass hierarchy problem. We actually don't

26:53

know what the heaviest and what the light is the

26:58

differences in their masses but of course if

27:00

I tell you that the difference between object

27:02

A and object B is 5 kilograms you

27:05

don't know if A or B is heavier,

27:07

right? You just know the difference and

27:09

we know these differences from

27:11

neutrino oscillation. So

27:14

then there's something called the

27:16

normal hierarchy or the inverted hierarchy which gives

27:18

you two different possible orderings of the masses.

27:20

So this is something that came through and

27:22

it's going to try to resolve through this

27:24

sort of in this much denser detector called

27:26

ORCA and that's going to be studying neutrinos

27:29

at lower energies and it's actually studying neutrinos

27:31

that are produced by the constant rays hitting

27:33

the atmosphere and it's going to try to

27:35

work out the mass ordering, you know, weighing

27:37

the masses of the most common particles in

27:39

the standard model. I'd say most common technically

27:41

photons I think are more common but so

27:44

this is the other goal of K-M-Treno.

27:46

These are the two key science goals

27:48

of it. The lower energy what we

27:50

call atmospheric neutrinos because they come from

27:52

the constant ray interactions with neutrinos in

27:54

the atmosphere and using these neutrinos to

27:56

understand the mass ordering of neutrinos and

27:59

it's that measurement. may turn up

28:01

something that isn't consistent with the standard

28:03

model of particle physics right as possible,

28:05

we could get hints of the dark

28:07

matter candidate there. And then the other

28:09

aspect is looking at the high energy

28:11

astrophysical neutrinos where we'll be studying neutrinos

28:13

from these particle collisions in the vicinity

28:15

of black holes or exploding stars and

28:17

that's going to tell us about the

28:19

sort of most violent and powerful processes

28:22

in the universe. One of the most

28:24

fascinating things about the explosion of Supernova

28:26

1987A was that the neutrinos

28:29

arrived slightly before the visible light

28:31

and that's because the visible light

28:33

had to travel through all the

28:35

turbulence and refuse and debris of

28:37

the Supernova explosion itself whereas the

28:39

neutrinos being so weakly interactive just

28:41

traveled in a straight line. Exactly.

28:44

Yes. So it's interesting

28:47

that people think of Supernova as these

28:49

optically bright things but actually most of

28:51

the energy in a Supernova gets emitted

28:53

as neutrinos. So a Supernova is basically

28:55

a neutrino explosion that has this tiny

28:57

optical signature. And I love that because

28:59

that is exactly the right definition. One

29:02

thing worth noting is that the neutrinos

29:04

that we detected from Supernova 1987A and

29:07

the Sun are at much lower energies

29:10

than the neutrinos that KM3Net will be

29:12

studying. So the lowest energy neutrinos that

29:14

KM3Net will be studying are merely a

29:16

thousand times more energetic than the neutrinos

29:18

we detect from solar neutrinos and

29:21

the highest energy ones will be more like

29:23

a million times as energetic or perhaps even

29:25

a billion times as energetic actually when I

29:27

think about it. Being so far down in

29:29

the ocean I guess you don't have to

29:31

worry about things like storms and that sort of

29:33

stuff but what about the dust

29:35

or some of the dust is it? Just the

29:38

type, the

29:41

trisis that's floating down there at that

29:43

depth? Is that a problem for the

29:46

detectors? Yes,

29:48

so actually there's a whole lot of oceanographic

29:50

physics, oceanographic science that I had no idea

29:52

existed and now do because I'm still working

29:54

with KM3Net. So the other thing to note

29:57

by the way is that KM3Net is a

29:59

very good way to do it. had a

30:01

predecessor instrument Antares about

30:04

2% the size of what KM3Net will

30:06

be. So we know exactly how it's

30:08

going to operate because of our experience

30:10

with this previous instrument. So

30:14

in terms of our experience with this thing, this

30:16

stuff you're talking about, this detritus are one of

30:18

the official names of this is Gelbstoff, so

30:21

yellow stuff in German. And

30:24

this is also known as marine snow. So

30:26

one of the problems is that this

30:29

sometimes accumulates on the top of your

30:31

light detectors, right? And

30:34

we'll block them. What you find though is that

30:36

every now and then you get stronger undersea currents

30:38

because there's still currents in the ocean even down

30:40

at two and a half kilometers. And so what

30:42

you can do is you can say, well as

30:45

time goes on more and more of this marine

30:47

snow accumulates on the top of your instrument. So

30:49

the light detectors that are facing upwards get a

30:51

bit less sensitive and a bit less sensitive. Then

30:54

there's a period where there's a higher oceanographic current,

30:56

it washes the detectors clean and then the sensitivity

30:58

goes up again. And then time goes on and

31:00

it slowly gets less sensitive and then there's

31:02

another high climate event and what is it clean?

31:04

So you see all these sort of interesting effects

31:07

in your instrument from the ocean floor. Here one

31:09

of the other interesting things you do is that

31:11

you're throwing a detector into the ocean. The

31:13

way it's set up is that the optical detectors are

31:15

held on string. These

31:18

are very long pieces of mostly

31:20

nylon cable, say 700 meters long.

31:24

And these currents I mentioned will cause these

31:26

strings to sway in the ocean. Now when

31:28

you detect this light signature of a neutrino,

31:30

you need to know where your detectors were

31:33

when they detected it so you can reconstruct

31:35

the direction neutrino came from. So

31:37

what you do is you use acoustic pingers

31:39

and sensors. So you have some pingers that

31:41

go ping from known locations on the seabed

31:44

and then you have detectors which will listen

31:46

for this and then you can measure it

31:48

by measuring the distances from the pinger to

31:50

the acoustic receiver. You can find out where

31:52

your instrument is. So okay, that's a technical

31:54

detail. The cool thing about this is that it

31:56

means you hear everything else going on in the

31:59

ocean such as... and whale song. You

32:04

can use this detector to track sperm whales

32:06

and because you've got an array of many

32:09

many of these receivers, there's actually ocean science

32:11

groups that use the data from what to

32:13

me is just a calibration instrument to actually

32:16

track the feeding patterns of sperm whales and

32:18

see what time of day they're feeding because

32:20

these things can dive down or like a

32:22

kilometer or more deep into the ocean. It's

32:25

amazing. I think it might be even a

32:27

kilometer and a half or so. It's a huge depth. What

32:29

they do is when the hunting squid, they have

32:31

a sonar that pings off the front of

32:33

the whale and then you can also see

32:35

this ping go forward that you can detect.

32:37

You also get a reflection off the back

32:39

of the whale skull. So by measuring the

32:41

time between the initial sort of whale ping

32:44

if you like and the reflection, you can

32:46

get an estimate for the size of the

32:48

whale. So there's all sorts of fascinating studies

32:50

you could do. That's Dr

32:52

Clancy James from Curtin University and

32:54

the International Centre for Radio Astronomy

32:56

and Research. This

32:58

is Space Time. In

33:15

case we haven't met, I'm Dino Colombo. I

33:18

represent people hurt by a truck. It's what

33:20

we do every day. I've

33:22

seen truck accidents devastate families, but

33:24

we can help. Not by a

33:26

truck. Call Colombo Law. And

33:30

time now to take a brief look at some of

33:32

the other stories making use in science this week with

33:35

the Science Report. New

33:37

observations have confirmed that April 2024 was the hottest

33:39

month on record and the eleventh

33:42

consecutive month of record heat.

33:45

The European Union's Copernicus Climate Change Service

33:48

made the observations based on both

33:50

surface and satellite data which confirmed

33:52

that April 2024 was globally warmer

33:54

than any previous April dating back

33:56

to 1940. 1.58

34:01

degrees Celsius warmer than the estimated

34:03

average for pre-industrial levels. It

34:05

follows a string of record hot months starting

34:07

from the hottest June on record last year.

34:10

Global warmings added 1.25 degrees Celsius to

34:13

global average temperatures since pre-industrial times and

34:15

the El Niño added an additional quarter

34:17

of a degree on top of that.

34:20

Overall, the data shows that planet Earth

34:22

is warming by roughly 0.25 degrees Celsius

34:26

per decade. That's up from

34:28

the way it was warming 25 years ago when

34:30

it was more like 0.2 degrees Celsius per

34:33

decade. Meanwhile, scientists say the summer of

34:36

2023 was overall

34:38

the warmest in the northern hemisphere's tropical

34:40

regions for the past 2000 years. A

34:44

report in the journal Nature reconstructed the past

34:46

2000 years of land

34:48

temperature data based on tree rings

34:50

and combined this with observational measurements

34:52

of more recent temperature records. They

34:55

found that the summer of 2023 exceeded

34:57

pre-instrumental average temperatures for the years 1

34:59

to 1890 CE by 2.2 degrees Celsius

35:01

and was 2.07 degrees Celsius higher in

35:04

the summer

35:07

of 2023 than instrumental averages between 1850

35:09

and 1900 CE. A

35:14

new study based on 20 years of

35:17

research has now confirmed beyond any reasonable

35:19

doubt that plant-based foods are better for

35:21

your health than a meat-based diet. The

35:24

findings reported in the journal PLAS 1

35:26

found that vegetarian and vegan diets are

35:28

better than meaty ones for your heart

35:31

health and chances of avoiding cancer. The

35:33

research is based on 48 individual studies,

35:35

all of which were conducted since the year

35:39

They found that overall, vegetarian and

35:41

vegan diets were strongly linked with

35:43

reduced risks of heart disease, type

35:46

2 diabetes, cancer and premature death.

35:49

That's because it results in improvements in

35:51

blood pressure and blood sugar management and

35:53

lower body mass index. Primary

35:55

plant-based diets were linked with reduced risk

35:57

of heart disease caused by arteries narrowing.

35:59

growing gastrointestinal and prostate cancer and

36:02

dying early from heart disease. However,

36:05

in pregnant women, they found

36:07

no benefits of plant-based diets

36:09

incurbing gastrointestinal diabetes or high

36:11

blood pressure. A

36:14

new study claims that males with low

36:16

levels of testosterone may have an increased

36:18

risk of dying prematurely. The

36:21

findings reported in the Journal of the

36:23

Annals of Internal Medicine follow an investigation

36:25

looking at the relationship between testosterone and

36:28

other sex hormone levels together with health

36:30

in aging men. The authors

36:32

reviewed the results of 11 previous studies

36:34

measuring the sex hormones of a total

36:37

of 24,000 men using the same technique,

36:39

all following up with participants for at

36:41

least five years. When

36:43

they re-analyzed all the data together, researchers

36:46

found men with low levels of testosterone

36:48

concentrations at a higher risk of dying

36:50

from any cause and men with very

36:52

low testosterone concentrations at a higher risk

36:54

of dying due to heart problems. There's

36:58

been yet another call for an

37:00

investigation into the authenticity of the

37:03

shroud of Turin. The shroud

37:05

is believed by some to be the death

37:07

shroud of Jesus Christ. But

37:09

multiple scientific studies, including carbon dating,

37:11

have conclusively proven that it was

37:14

actually created in the 12th century.

37:16

Jim Mendham from Australian Skeptics says it's all

37:19

part of a new film which fails to

37:21

provide any new evidence. There's a bit of

37:23

an industry of documentaries on the Shroud of

37:26

Turin and books on it, etc. It's

37:28

an ongoing debate despite scientific investigations, it

37:31

doesn't seem to go away. Now the

37:33

Shroud of Turin is a cloth, I

37:35

think everyone knows probably, it's a cloth

37:37

that supposedly shows that was wrapped around

37:40

Jesus after the crucifixion and the story

37:42

goes that for some reason his image

37:44

was imprinted on the cloth. Okay. So

37:47

the Shroud of Turin is now kept in the Cathedral

37:49

in Turin and shown every nth number of years, not

37:51

very often, and when it is you get crowds coming

37:53

to see it. The trouble is you can't see much

37:56

because it's actually pretty faint and vague but if you

37:58

take a photo of it, you can see it. it

38:00

and put it in negative you actually see a

38:02

lot more. Do we have negative photos anymore? I

38:04

don't know. But certainly in the old days when

38:06

you took a photograph you got a negative and

38:08

that's when someone said, oh there's a lot more

38:10

detail here than we thought. So the detail includes

38:13

a look like blood from a crown of thorns

38:15

might have left or caused not the crown itself.

38:17

It looks like holes in his hands where he

38:19

would have been crucified which is not the way

38:21

you're crucified at the time but never mind. We'll

38:23

leave that once at the time being and that

38:25

he has possibly broken arms, he possibly has a

38:27

spear, certainly a hole in his side where the

38:29

story goes that a Roman soldier speared him

38:32

which is what they used to do to

38:34

kill someone off rather than just hang around

38:36

there all the time being miserable. Now this

38:38

story goes that when did the this shroud

38:40

first appear and the church did a bit

38:42

of investigation, Catholic Church did a bit of

38:44

investigation, they found that it was really sort

38:46

of about medieval days, twelve hundred something like

38:48

that and there are stories about it and

38:50

some illustrations of it having been found or

38:52

at least displayed and discussed around that time.

38:54

There's also somewhere that there's a record of

38:57

a word of warning about it saying there's

38:59

this guy hoisting this shroud around as a

39:01

bit of a tourist thing, a bit of

39:03

a circus object and it's a fake. Now

39:05

what it comes down to is is the

39:07

shroud as we know it, a genuine object

39:09

from the first century CE wrapped around Jesus

39:11

and that shows him his image etc. Whole

39:13

body image front and back or is it

39:15

something that was made up a thousand years

39:17

later for a bit of a tourist thing,

39:19

a bit of a miracle cloth. There's been

39:22

scientific investigations of it over and over and

39:24

over again. Part of the problem was that

39:26

at one stage the cloth was folded like

39:28

you make that up in a folded towel

39:30

or a sheet and put away and there

39:32

was a fire in the place where it

39:34

was being stored and some I think silver

39:36

reliquary melted onto the cloth and where it

39:38

was folded it got burnt. So when you

39:40

unfold it you get these little burn marks

39:42

of various places around the whole trap and

39:45

they're suggesting that that might have impacted on

39:47

the image. Certainly you can still see the

39:49

image but you can see there's burn bits

39:51

pretty clearly but scientific tests, x-ray,

39:53

carbon dating which is not crash on to this

39:55

sort of thing but you know looking at the

39:57

cloth itself, looking at any herbal or you know

40:00

seeds or any residue in the cloth, looking at

40:02

the historical record where it's been, etc. I think

40:04

I first appeared in France somewhere. A group called

40:06

the Shroud of Turin Research Project had a lot

40:08

of people involved. Some people have complained that some

40:10

of the... It had dozens of people involved, physicists

40:12

and chemists and all sorts of people. This is

40:14

the one where they took samples to different universities.

40:17

That's right. To at least three different universities, I

40:19

think, to try and get carbonating and they all

40:21

came back the same or pretty close to each

40:23

other. As much as you can get an accuracy

40:25

of carbonating for something that old and they all

40:27

came back with it as being about 1200s roughly

40:30

around there, suggesting that the Shroud is not an

40:32

ancient bit of material. That would have been around

40:34

at the time of Jesus. It is a bit

40:36

of material that was woven in 1200s and therefore

40:39

the image, the suggestion therefore is the image states

40:41

from the same time. So that was the agreement

40:43

that came out of there. Now people are saying,

40:45

oh well, we can't trust them. Someone is suggesting

40:47

in a recent article, a recent documentary that's coming

40:49

out about the Shroud that you can't trust because

40:52

some of the scientists were agnostics. You think, well

40:54

some of them were scientists. I mean, which one?

40:56

You only try to... One would sort of hope

40:58

they were agnostic. They would hope they were.

41:00

Yeah, you'd hope you get a mixture of

41:02

some people who were agnostic. You want someone

41:04

who's not going to be biased in their

41:07

reporting, in where they carry out their study.

41:09

That's exactly right. And this documentary thinks only

41:11

an agnostic would be biased against the Shroud.

41:13

Obviously, those who are religious people are not

41:15

going to be biased. No, they wouldn't care.

41:17

An agnostic wouldn't care. That's right. Well, it

41:19

might be a bit antagonistic to it but

41:21

really if you're agnostic rather than atheists say.

41:24

Exactly. An atheist would care. It

41:26

would be more equanimity. But anyway, this has been going

41:28

on and on and on for ages and supposedly

41:30

finding new evidence. These keep popping up. There's

41:32

been others that have been investigating it over

41:34

the years, various things and some came back

41:36

saying, oh it is a real cloth or

41:38

the image is not new. It's not as

41:40

old as the cloth or that cloth is

41:43

not ancient. It's just thousand years old, etc.

41:45

etc. And it's a messy area especially if

41:47

the church doesn't really like putting it out

41:49

for everybody and their dog coming and taking

41:51

a snip of it. Now look, I tell

41:53

you what, if it was real,

41:55

it'd be a pretty weird looking person to

41:57

start with, wouldn't it? Yes. It's

42:00

a very elongated image. The arms,

42:02

the forearms in particular look too

42:04

long. The way it's sort of

42:06

great doesn't almost... There's

42:08

two aspects. Some say someone created a statue or

42:11

a carving of a man lying down, put a

42:13

cloth over it, did a rubbing as you can

42:15

do on church tombs and that sort of stuff.

42:17

Did a rubbing with some sort of material, with

42:19

some sort of chemical and did a both sides

42:21

turning over, flipping him over, put the shroud. The

42:23

shroud is in one long piece that goes from

42:25

the head down to the toes and then back

42:27

up again up the back. So the suggestion is

42:29

that he was using a carving or an

42:31

actual person who didn't mind sitting there and

42:33

being messed around with. And therefore some of

42:35

the elongation and some of the weird things

42:37

that because the distortion from the way the

42:40

cloth was draped over the person or the

42:42

statue. Others would say that because the image

42:44

on the cloth is supposedly

42:46

a discharge when Jesus was resurrected, which

42:48

is the suggestion that it was near

42:50

the zap and suddenly get his image

42:52

implanted on the cloth, that that should

42:54

be more accurate as to a physical

42:56

person. I mentioned before about the holes

42:58

in the hands. People who crucify

43:01

would normally and crucifixion was fairly common

43:03

in those days. You see Spartacus, everyone

43:05

gets crucified at the end of Spartacus.

43:07

That was a fairly common punishment. I'm

43:09

Spartacus. No, I'm Spartacus. No, I'm Spartacus

43:11

and so is my wife. The

43:14

crucifixion you'd normally be tied up, rope around your

43:17

arms and tied to a cross. That's a nailing

43:19

someone to a cross that was certainly not common,

43:21

I don't think. But if you're going to nail

43:23

someone to a cross, you have to do it

43:26

through the wrist. If you do it through the

43:28

hand, the palm of the hand unfortunately it

43:30

tears straight through between your fingers or you

43:32

pulled off. That's a bit nasty because your

43:34

weight is leaning forward and your hand pulls

43:36

straight, the nail goes straight through your hand

43:38

or it comes out between the fingers etc.

43:40

That's even nasty. You put it through the

43:42

wrist and then the nail can't move because

43:44

it's stopped by the hand bones. So

43:47

the wrist is a bit of place. If you're going

43:49

to nail someone to a cross, you do it through the

43:51

wrist. After nailing their feet, half the time their feet

43:53

was on a platform, half the time there wasn't. The

43:55

way you die generally was that you suffocated because your arms

43:57

are up and don't try hanging up on your arms

43:59

for time. long, it's not good for your

44:01

chest, not good for your lungs and therefore after

44:03

a few hours the person might be a bit

44:06

of suffering and which is when the soldier comes

44:08

along and sticks a spear in your side to

44:10

basically hurry things along. Now Jesus was supposed to

44:12

be up there for a long time, they took

44:15

him down alive buried in a cave, rolled a

44:17

rock, unrolled a rock, he's not there, it's a

44:19

shroud still works. So this is a story that's

44:21

going on for a long, long time. It's interesting

44:24

as romantic that apparently scientifically it doesn't hold up

44:26

that well. But for the religious people, they believe

44:28

it. It's Tim Endham from Australian Skeptics. And

44:46

that's the show for now. Space

44:49

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