Become a supporter of this podcast: https://www.spreaker.com/podcast/spacetime-with-stuart-gary--2458531/support.
00:00:00
This is Space Time series 26 episode, 100 and six for
00:00:03
broadcast on the fourth of September 2023. Coming up on
00:00:07
Spacetime, the violent accretion disc of a super massive black
00:00:12
hole studying the nearby monster Centaurus A and India's Lunar
00:00:17
Rover confirms the existence of sulfur at the Moon's South Pole.
00:00:22
All that and more coming up on Space Time.
00:00:27
Welcome to Space Time with Stuart Garry.
00:00:46
Astronomers have for the first time ever captured the turbulent
00:00:50
violence of an accretion disk in an actively feeding supermassive
00:00:54
black hole. The findings reported in the Astrophysical
00:00:58
journal letters provide scientists with their first
00:01:01
direct observations of this hard to see region inside one of the
00:01:05
biggest monsters in the universe.
00:01:08
Supermassive black holes are the most powerful objects in the
00:01:11
universe. There are intense gravity wells, regions of
00:01:16
infinite density in zero volume where the gravitational pull is
00:01:20
so strong that nothing, not even light can escape clouds of gas
00:01:25
planets and even stars venturing too close to a black hole will
00:01:30
be torn apart by the monster's intense gravity.
00:01:33
There remains swirling around the black hole in an accretion
00:01:36
disk like water swirling around the drain in a sink material in
00:01:40
the accretion disk is constantly being crushed, stretched and
00:01:44
ripped apart in the process, releasing vast amounts of energy
00:01:48
at billions of degrees.
00:01:50
The subatomic debris then passes beyond a point of no return
00:01:54
called the event horizon. Once inside the event horizon, escape
00:01:59
velocity becomes greater than the speed of light.
00:02:01
And since nothing can travel faster than the speed of light,
00:02:04
nothing not even light can escape a black hole. Hence, the
00:02:08
name here matter is beatified as it falls forever towards the
00:02:13
singularity, a place where the laws of physics as science
00:02:16
understands them breaks down, but not all the material in the
00:02:20
accretion disk is doomed to disappear into the black hole.
00:02:23
Some of the superheated material is deflected along powerful
00:02:27
magnetic field lines away from the event horizon and out
00:02:30
towards the black hole spin axis which accelerates perpendicular
00:02:34
out from the accretion disk into space.
00:02:37
Here, the material is accelerated to relativistic
00:02:40
speeds and focused into intense superluminal jets called
00:02:43
quasars. These are the brightest objects in the known universe.
00:02:48
They shine out like beacons in the darkness and can be visible
00:02:52
over 13 billion light years away. Studying these accretion
00:02:56
disks can therefore enhances science's understanding, not
00:02:59
just of black holes but of the evolution of their host
00:03:02
Galaxies.
00:03:03
And maybe the universe itself. The problem is most accretion
00:03:07
discs are actually quite difficult to study directly.
00:03:10
That's because they're actually a long way away and really
00:03:13
small.
00:03:14
But scientists using the Gemini North telescope have now made
00:03:18
the first detection of two near infrared emission lines coming
00:03:21
from the accretion disc of a galaxy three ZW 02 in the
00:03:26
process, placing new limits on the size of these magnificent
00:03:30
structures. Emission lines are caused when an atom in an
00:03:33
excited state drops to a lower energy level releasing light in
00:03:37
the process.
00:03:38
Now, since every atom has a unique set of energy levels, the
00:03:42
emitted light has a discrete wavelength and acts like a
00:03:45
fingerprint, identifying its origin emission lines commonly
00:03:49
appear in spectra as thin sharp spikes.
00:03:52
But in the unique environment of the swirling vortex of an
00:03:56
accretion disk where the excited gas is under the supermassive
00:03:59
black hole's gravitational influence and where it's moving
00:04:02
at speeds of thousands of kilometers per second, those
00:04:05
emission lines are broken into shallower peaks. The part of the
00:04:09
accretion disk where these lines originate is called the broad
00:04:12
line region.
00:04:13
And evidence of an accretion disc can be found in a specific
00:04:17
pattern of broad emission lines called a double peak profile.
00:04:22
Now, because the accretion disc is rotating the gas on one side
00:04:25
of the disc is moving away from the observer or the gas on the
00:04:28
other side is moving towards the observer.
00:04:31
And these relative motions act the same way as the Dora affect
00:04:35
you hear. When a siren goes past changing pitch, the light waves
00:04:39
moving away from the observer tend to be stretched, it's
00:04:42
called red shifting. While those traveling towards the observer
00:04:45
are compressed or blue shifted.
00:04:48
So the result from all this is a broadened line with two distinct
00:04:51
peaks, one are returning from each side of the rapidly
00:04:55
spinning accretion disk. Now, these double peak profiles are a
00:04:58
rare phenomenon. That's because their currencies limited to
00:05:01
sources that can be observed or nearly face on.
00:05:04
But in the few sources where it has been observed, the double
00:05:07
peak tends to be found in the H alpha and H beta lines. Two
00:05:11
emission lines for hydrogen atoms that appear in the visible
00:05:15
wavelength range originating from the inner area of the broad
00:05:19
line region near the supermassive black hole.
00:05:21
These lines normally don't provide any evidence about how
00:05:24
big the accretion disk is. But recent observations, the near
00:05:28
infrared have revealed an area of the outer broadly region that
00:05:31
has never been seen before.
00:05:34
A team of astronomers from Brazil's National Laboratory Of
00:05:37
Astrophysics have for the first time detected two near infrared
00:05:41
double peak profiles in the broad line region of the black
00:05:45
hole in galaxy three ZW 02, the hydrogen line originates in the
00:05:50
inner area of the broad line region and a neutral oxygen line
00:05:54
originates in the outskirts of the region, an area that's never
00:05:58
been observed before.
00:06:00
These are the first double peak profiles to be found in the near
00:06:03
infrared and they emerged quite unexpectedly during routine
00:06:07
observations using the Gemini's near infrared spectrograph. Back
00:06:12
in 2003 observations of three ZW 002 1St revealed evidence of an
00:06:18
accretion disk.
00:06:19
And then a 2012 study found similar results and this meant
00:06:23
there was a black hole that had been actively feeding. So in
00:06:27
2021 the Brazilian team set out to supplement these findings
00:06:31
with fresh observations in the near infrared using Gemini,
00:06:34
which has the advantage of being able to observe the entire
00:06:37
infrared spectrum in one go.
00:06:39
And that's actually quite a big advantage. You see other
00:06:42
telescopes require the user to switch between multiple filters
00:06:46
in order to cover the same range that's time consuming. And also
00:06:51
it introduces uncertainties such as changes in atmospheric
00:06:54
conditions and the problems of calibration changes between
00:06:58
observations.
00:06:59
But because Gemini North is capable of making simultaneous
00:07:02
observations across multiple bands of light, the team were
00:07:05
able to capture a single clean, consistently calibrated spectra
00:07:09
in which multiple double peak profiles were revealed.
00:07:13
The observations not only confirm the theorized presence
00:07:17
of an accretion disc but also advance science's understanding
00:07:20
of this broad line region. It also provides clear evidence of
00:07:24
the feeding process and the inner structure of an active
00:07:28
galactic nuclei. By comparing these observations with existing
00:07:32
disc models.
00:07:33
The authors have been able to extract parameters that provide
00:07:35
a clearer picture of three Z 02 super massive black hole as well
00:07:41
as the broad lion region of its surrounding accretion disk. The
00:07:45
observations suggest that the hydrogen alkaline exists at a
00:07:48
radius of 16.77 light days as measured from the supermassive
00:07:52
black hole.
00:07:54
And the neutral oxygen line originates at a radius of 18.86
00:07:58
light days. By comparison, the distant ward of Pluto is just
00:08:03
5.5 light hours from earth. In other words, the accretion disk
00:08:07
around this black hole is larger than our solar system.
00:08:11
In fact, the outer radius of the broad line region is estimated
00:08:15
to be 52.43 light days. The model also indicates that three
00:08:20
ZW 00 two's broad line region has an inclination of about 18
00:08:25
degrees with respect to the earth and the super massive
00:08:29
black hole at its center.
00:08:30
Well, it's somewhere between 400 million and 900 million times
00:08:34
the mass of our Sun. A true monster. This is Space Time
00:08:40
still to come stabbing the monster galaxy and black hole
00:08:43
Centaurus A and India's Lunar Rover confirms the presence of
00:08:48
sulfur on the Lunar South Pole. All that are more still to come
00:08:53
on Space Time.
00:09:10
Well, while we're on the subject of black holes, astronomers have
00:09:13
combined two major Australian radio telescopes and several
00:09:17
optical telescopes to study complex mechanisms that are
00:09:20
fueling jets of material blasting out of a supermassive
00:09:24
black hole some 55 million times more massive than the Sun.
00:09:28
The research focused on a nearby radio galaxy known as Centaurus
00:09:33
A which it's somewhere between 11 and 13 million light years
00:09:36
away. Is the nearest radio galaxy to the earth radio
00:09:40
Galaxies are those with active galactic nuclei or a GNS,
00:09:45
meaning their central supermassive black holes are
00:09:48
busy consuming material releasing vast amounts of energy
00:09:52
in the process.
00:09:54
A report in the monthly notices, the Royal Astronomical Society
00:09:57
shows that as well as detecting the plasma that's fueling the
00:10:00
large plumes of material.
00:10:01
The galaxy is famous for the authors also found evidence of a
00:10:04
galactic wind or high speed stream of particles moving away
00:10:08
from the galaxy's core, taking energy material with it as it
00:10:11
impacts the surrounding galactic environment. These new
00:10:15
observations of Centaurus A will allow astronomers to apply the
00:10:19
knowledge to hypotheses and simulations of how Galaxies
00:10:22
evolve.
00:10:23
One of the study's authors, Ben McKinley from the Curtin
00:10:26
University node of the International Center For Radio
00:10:29
Astronomy Research says the galaxy's proximity just down the
00:10:33
road in astronomical terms, makes Centaurus say a perfect
00:10:36
cosmic laboratory for studying the physical processes
00:10:39
responsible for moving material and energy away from the
00:10:43
galactic core.
00:10:44
Centaurus A has been a popular target for astronomers in the
00:10:47
southern hemisphere for decades due to its size, its elegant
00:10:51
dust lanes and its prominent plumes of material.
00:10:55
But McKinley says that being so close to earth and so big
00:10:58
actually makes studying this galaxy a bit of a challenge.
00:11:02
That's because most of the telescopes capable of resolving
00:11:05
the details needed for this type of work have fields of view
00:11:08
which is smaller than the area of the sky that Centaurus takes
00:11:12
up.
00:11:13
So to undertake their observations. McKinley and
00:11:16
colleagues use the Murchison wide field ray radio telescope
00:11:19
in Outback, Western Australia and the Parkes radio telescope
00:11:22
in the central west of New South Wales, both of which have large
00:11:26
fields of view, thereby allowing them to image a large portion of
00:11:29
the sky and see all of Centaurus 's Ale.
00:11:32
Once Murchison is a low frequency radio telescope, it
00:11:37
has superb sensitivity allowing the large scale structure of ST
00:11:41
Tous A to be imaged in great detail. And the 64 m Parks
00:11:46
observatory commonly known as the dish can complement these
00:11:49
observations.
00:11:50
Additional observations from several optical telescopes were
00:11:54
also used in this work including the magnificent Magellan
00:11:57
telescope in Chile, as well as several smaller telescopes such
00:12:01
as the to observatory in Canberra and the high view
00:12:03
observatory in Auckland, also known as NGC 51 28 Centaurus A
00:12:10
is in the constellation Centaurus.
00:12:13
It was discovered back in 18 26 by Scottish astronomer James
00:12:17
Dunlop from his home in Parramatta. Nowadays, Parramatta
00:12:21
is located in the middle of Sydney's sprawling western
00:12:24
suburbs about 200 years ago. It was a mixture of pristine
00:12:28
forests and rural pasture lands.
00:12:30
There's considerable debate in the literature regarding
00:12:33
Centaurus A's fundamental properties such as its exact
00:12:37
distance from our solar system, also whether it's a lenticular
00:12:41
galaxy or an elliptical 11 thing scientists are sure about is
00:12:45
that it's the most powerful radio source in the region with
00:12:48
an active galactic nuclei that's been extensively studied.
00:12:53
The galaxy is also the fifth brightest in the night sky
00:12:55
making it ideal not just for professional astronomers but
00:12:58
also amateur astronomers as well. It's best visible from the
00:13:02
southern hemisphere or from very low northern latitudes by
00:13:07
comparing radio and optical observations of the galaxy.
00:13:10
The killing. And colleagues also found evidence that stars
00:13:13
belonging to Centaurus are extending far further out from
00:13:17
the galactic core than previously thought. And that's
00:13:20
led to speculation about whether the winds and jets emanating
00:13:23
from the galaxy could be physically pushing those stars
00:13:26
away.
00:13:27
Centaur so close by. And so with our radio telescopes and the
00:13:33
optical telescopes as well, we're able to see it in more
00:13:36
detail than any other radio galaxy in the universe. And so
00:13:39
by learning about Centaurus, a, we can then assume that similar
00:13:45
things are happening in radio Galaxies further away.
00:13:48
And we can put that into our cosmological simulations and try
00:13:52
and work out basically how the universe has evolved in time
00:13:57
since the Big Bang. We've used two radio telescopes in
00:14:00
Australia and three optical telescopes to study the closest
00:14:04
radio galaxy Centaurus.
00:14:06
A in new detail, we're looking for relationships between the
00:14:09
optical and the radio emission and what's happening with the
00:14:12
interaction between the supermassive black hole and the
00:14:15
environment around the galaxy Centaurus A is unique in that it
00:14:18
's the closest radio galaxy by far.
00:14:20
So we can use very long baseline interferometry to study those
00:14:24
jets in the best detail of any other supermassive black hole
00:14:27
outside of our own galaxy. So we know quite a lot about the jets.
00:14:32
It actually gets harder when you look further out from the jets,
00:14:36
the jets create these radio loaves that are actually quite
00:14:40
large on the sky. And that makes it more difficult for some radio
00:14:45
telescopes to have much smaller small fields of view.
00:14:48
So the merch and wide field array that we've used and parks
00:14:51
as well, you're actually able to map the whole radio source and
00:14:54
really learn what's happening in those radio loads that are
00:14:57
created by the jet. How are the jets created?
00:14:59
So there's a super massive black hole in the middle of the galaxy
00:15:04
and matter spirals into that super massive black hole and
00:15:07
forms what's called an accretion disk and things become super hot
00:15:11
and then super fast they enter that disk. And so basically as
00:15:15
the supermassive black hole eats matter, some of that matter is
00:15:19
shot out in jets that go either side, sort of perpendicular to
00:15:24
the galaxy.
00:15:26
And it's because this matter, mostly electrons traveling close
00:15:30
to the speed of light. When you get electrons traveling that
00:15:32
fast, they create radio waves. And so that's why we see these
00:15:35
bright jets when we look at the galaxy with a radio telescope.
00:15:38
And these powerful jets are formed and that shoot out these
00:15:42
are the same sort of things that when we see across the universe
00:15:45
we call them quasars. Is that right? Yeah, that's right. And
00:15:47
they've got other names too. Blazers and a GNS. I take it
00:15:51
that's all the same thing. Just depends on how we see it and
00:15:53
where it.
00:15:54
Is, it's basically the same thing. I think quasars are
00:15:57
normally the classified as the ones that are sort of from the
00:16:01
early universe really far away. And so they're really compact
00:16:04
and really, really bright and the name comes from quasi
00:16:08
stellar object.
00:16:10
So they sort of look like stars because they're just single
00:16:14
points, whereas radio Galaxies is sort of the same thing, but
00:16:18
it's generally the things that are closer and you can start to
00:16:20
resolve them and see more of the structure. I think blazer is to
00:16:23
do with the orientation angle of the radio galaxy.
00:16:27
So there's this sort of grand unified theory of active
00:16:30
galactic nuclei where people think it's all basically the
00:16:33
same thing. But depending on the different orientations of the
00:16:37
radio galaxy, depends on whether you're classified as a blazer or
00:16:41
a radio galaxy or a quasar.
00:16:43
And what you guys have been doing is looking at what happens
00:16:46
when this jet shoots out from the black hole and interacts
00:16:50
with the surrounding interstellar medium, I guess.
00:16:53
Yeah, that's right. So as the jet propagates out when it hits
00:16:57
gas, that's going around the galaxy. So some other studies
00:17:00
have found these big h one clouds clouds of hydrogen that
00:17:04
are going around the surrounding the galaxy.
00:17:07
And as they interact with that, they can create more radio
00:17:10
emission and X ray emission, the jets can trigger star formation
00:17:15
as well and they can ionize the surrounding gas. So you end up
00:17:20
UV radiation from the A causes electrons to be knocked off the
00:17:25
hydrogen. And we can detect this with the optical telescopes by
00:17:28
looking for different radio emission lines.
00:17:32
People are often very surprised when they hear that black holes
00:17:35
which are these things like giant vacuum cleaners. Some
00:17:37
people envisage them as being that are just sucking up the
00:17:41
universe around them. But as well as that, they do generate
00:17:43
these powerful jets, they're feeding and these jets can push
00:17:46
material away from the line of fire, I guess you'd call it. And
00:17:50
in the process that can lead to increased star formation as
00:17:54
well.
00:17:55
Yeah, that's right. So we see these bright optical filaments
00:17:58
that we describe in the paper and we show an image of it. And
00:18:01
yeah, the bright new stars in those filaments are thought to
00:18:06
be caused by interactions from the AGN with the surrounding
00:18:11
gas.
00:18:11
And they're a lot further out than originally thought too,
00:18:13
the.
00:18:14
Stars, this deep optical image that we have shows this shell
00:18:17
surrounding the galaxy. But yeah, we've seen additional sort
00:18:21
of cloud of stars that seems to propagate out sort of in line
00:18:25
with the radio jets, but not quite out, quite a far distance.
00:18:28
And it's not exactly clear the mechanism that's causing that.
00:18:32
But due to the alignment with the radio galaxy jets and loads,
00:18:36
we sort of speculate that it has something to do with, with
00:18:39
propagation because of the ATM.
00:18:41
Has proven to be quite a valuable astronomical tool,
00:18:44
isn't it?
00:18:44
The wide field array? Yeah, it's really good because of the wide
00:18:48
field of view. So we lack the spatial resolution of a lot of
00:18:52
other telescopes. But we can see across a really wide field of
00:18:56
view.
00:18:57
If you look up at the sky and imagine 14 full moons across.
00:19:01
That's how big sur would be if you could see it with your eyes.
00:19:04
And most telescopes can see a tiny tiny fraction of that at
00:19:09
any one time. So with the M we are able to see the whole galaxy
00:19:12
and image image it across a wide range of wavelengths.
00:19:17
And that's especially important with something like Centaurus A
00:19:20
because it is so close.
00:19:21
Yeah, that's right. So part of our paper was also comparing our
00:19:25
observations with some older observations. One set of
00:19:28
observations was done with the Australia telescope compact
00:19:32
array, which is another inner fero which has a narrow field of
00:19:36
view, but is able to look in sort of more spatial detail and
00:19:39
then also the very large array in the US.
00:19:42
And so there was new observations from the very large
00:19:44
array that disputed the fact that there's this large scale
00:19:48
jet connecting the inner radio loads of with the outer radio
00:19:53
loads.
00:19:53
And our observations show that the very large array of
00:19:56
observations from the northern hemisphere are probably not
00:19:59
correct because of difficulties they have observing the source
00:20:02
because it's so low in the sky in the north. So, and we've
00:20:05
shown there is large scale jet connecting the inner lobes to
00:20:09
the outer lobes.
00:20:10
Do we know what these jets are composed of? You mentioned
00:20:12
electrons earlier?
00:20:13
Yeah, sure. So we think, yeah, they're mostly electrons because
00:20:17
electrons are small enough that they can be accelerated to close
00:20:19
to the speed of light and cause this radio emission that we see
00:20:23
it's much harder to.
00:20:27
That's astronomer Professor Ben McKinley from the Curtin
00:20:30
University nerd of the International Center For Radio
00:20:33
Astronomy Research and this is Space Time. Still to come. India
00:20:39
's Luna rover confirms the presence of sulfur at the Moon
00:20:42
South Pole. And later in the Science Report Discovery of a
00:20:46
cancer drug that could target HIV silent cells all that and
00:20:51
more still to come on Space Time.
00:21:09
India's Pragyan or Wisdom Lunar Rover has confirmed the presence
00:21:14
of sulfur at the Moon's South Pole. It's the first major
00:21:18
discovery by the tiny six wheeled rover since the Chandra
00:21:21
N Three S Vikram or valid ascent vehicle became the first
00:21:25
spacecraft to touch down near the Lunar South Pole iro.
00:21:29
The Indian Space Research Organization says the detection
00:21:33
of sulfur was made by the 26 kg rover's laser induced breakdown
00:21:37
spectroscopy instrument. It says these in situ measurements
00:21:41
confirm the presence of sulfur in the region unambiguously
00:21:45
something not feasible using instruments on orbiters.
00:21:48
The spectroscopic analysis also confirmed the presence of
00:21:51
aluminum calcium iron chromium and titanium together with
00:21:56
manganese silicon and oxygen and it's still continuing its search
00:22:00
for signs of frozen water. The solar powered rover will spend
00:22:04
half a loon a day.
00:22:05
The equivalent of 14 earth days exploring the terrain around
00:22:09
this relatively unmapped landing site, transmitting images and
00:22:12
scientific data back to mission managers on Monday, the rover's
00:22:17
exploration route had to be changed after venturing too
00:22:20
close to a 4 m wide crater. The rover's journey of exploration
00:22:24
on the Moon isn't fast traveling at just 10 centimeters per
00:22:28
second.
00:22:29
So as to minimize shark and damage from the Moon's rugged
00:22:32
terrain. The Chandra three or Moon three in Sanskrit mission
00:22:37
has captivated the Indian public 's imagination since its launch
00:22:41
six weeks ago, its successful touchdown on the Lunar surface
00:22:45
last week was viewed by thousands of cheering
00:22:47
Spectators.
00:22:49
An achievement made even more poignant by the Russian Lander
00:22:53
Lunar 25 crashing in the same region while attempting its own
00:22:56
competing landing. Mind you it hasn't been all beer and
00:23:00
skittles for the Indian Space Agency. A previous landing
00:23:03
attempt back in 2019 by the Chan Andrean two ended in failure.
00:23:08
In fact, only three other nations had achieved a soft
00:23:11
landing on the Moon, the Soviet Union, the United States also
00:23:15
the only country to have sent people there. And China. But
00:23:19
India is fast becoming a major player in the space industry. In
00:23:23
2014, India became the first Asian nation to achieve orbit
00:23:27
around Mars.
00:23:28
And it hopes to undertake its first manned space flight into
00:23:31
earth orbit next year. And Israel has just launched its
00:23:35
first scientific mission to observe the Sun.
00:23:38
The Aita L One will study the Sun from the Lagrangian L one
00:23:42
position about 1.5 million kilometers from earth Aita,
00:23:46
which means Sun in Hindi will be placed into a halo orbit around
00:23:50
L one which is a sort of gravitational balancing point
00:23:53
between the earth and the Sun. The orbit is shared by a number
00:23:57
of other Sun studying spacecraft including the joint NASA ESA
00:24:01
solar and Heliospheric observatory spacecraft.
00:24:04
Soho a ditch's mission is to try and understand the dynamics of
00:24:08
the solar wind using its seven scientific payloads including an
00:24:12
electromagnetic and particle light detector which will
00:24:14
observe the Sun's outmost layers, the photos sphere and
00:24:18
Chromos sphere. But the tiny spacecraft's first task will be
00:24:22
getting from earth orbit out to L one.
00:24:25
We'll keep you informed. This is Space Time and time. Now to take
00:24:46
a brief look at some of the other stories making news in
00:24:48
science this week with the science report, scientists have
00:24:52
found an existing blood cancer drug that shown promise in
00:24:56
killing silent HIV cells.
00:24:58
The discovery by researchers at the Peter Doherty Institute has
00:25:02
already been shown to help delay the virus from re emerging in
00:25:05
patients being treated with anti retroviral cocktails. Hidden HIV
00:25:10
cells known as Latin infection are responsible for the virus
00:25:14
permanently remaining in the body and cannot be treated by
00:25:17
current therapies.
00:25:18
The new findings published in the journal cell reports,
00:25:21
medicine are based on research in which scientists looked at
00:25:24
blood cells from patients infected with HIV and the impact
00:25:27
of the cancer drug venetoclax, both alone and in combination
00:25:31
with another drug known as S 63 845 they found that Venita
00:25:37
claques killed HIV, one lately infected cells and that the
00:25:42
drugs were able to delay the time it took for the virus to
00:25:44
bounce back once antiretroviral therapy had stopped a clinical
00:25:49
trial based on the findings will now be launched in Denmark and
00:25:52
Australia to test whether veda claques can be used as a
00:25:55
potential pathway to develop a cure for HIV.
00:25:59
There are an estimated 40 million people worldwide
00:26:02
currently living with HIV. The virus that causes AIDS included
00:26:08
in that count are more than 29 Australians.
00:26:13
Scientists have developed a new test which could help predict
00:26:16
who's likely to get dementia in the next 14 years. A report in
00:26:21
the British medical journal claims the test known as the UK
00:26:24
Bio bank dementia risk score was developed using data from over
00:26:28
200 people.
00:26:30
It works by looking at 11 predictive factors. These
00:26:34
include age education, a history of diabetes, a history of
00:26:38
current depression, a history of stroke, parental dementia,
00:26:41
economic disadvantage, high blood pressure, high cholesterol
00:26:45
living alone and being male.
00:26:48
The researchers also looked at whether people had the gene apo
00:26:52
E which is a known risk factor for dementia. When they use the
00:26:56
test on a separate group of 70 people aged between 50 73
00:27:01
the test performed better at predicting who would develop
00:27:03
dementia over 14 years than three other current dementia
00:27:07
tests.
00:27:09
Well, the biggest search in more than half a century has been
00:27:12
underway in the Scottish Highlands looking for the
00:27:14
elusive Loch Ness Monster. Hundreds of amateur researchers
00:27:18
and enthusiastic Nesi hunters from around the world have been
00:27:21
braving the pelting rains in order to scour the 36 kilometer
00:27:25
long 240 m deep lock, using everything from drones and
00:27:30
thermal imaging cameras to sophisticated sonars and
00:27:33
underwater hydrophones.
00:27:35
With the aim of unraveling a mystery that's captivated the
00:27:38
world's attention for generations. Reports of an
00:27:42
aquatic monster lurking in the lochs murky depths go back to
00:27:46
ancient times. There are even rock carvings in the area
00:27:49
depicting a mysterious beastie with flippers.
00:27:52
The earliest written record of the creature can be found in the
00:27:55
biography of the Irish Monk Saint Columba in the year 5, 65.
00:28:00
Since then, there have been thousands of alleged sightings
00:28:03
as commonly describing a prehistoric marine ripped off
00:28:06
from the age of the dinosaurs known as a plesiosaur. Of
00:28:10
course, chances of actually finding the mythical beast range
00:28:14
from slim to nonexistent.
00:28:16
Hundreds of blurry images and a couple of not bad fakes have
00:28:19
turned up. But if there really is something there, then it's
00:28:23
more likely to be a giant sturgeon, a humongous catfish or
00:28:27
possibly a new species of giant eagle. Other possibilities
00:28:31
include a lost seal or shark that swam along the canal
00:28:34
connecting the loch to the North Sea.
00:28:37
However, to be honest, the end of the legend really happened
00:28:40
back in 2018. That's when scientists from Otago
00:28:43
University, New Zealand undertook a detailed
00:28:46
environmental DNA search of the lock and they found no
00:28:50
unexplained DNA sequences in the lake's dark waters. Absolutely
00:28:54
nothing that could be attributed to Nese.
00:28:58
Well, they may just have reached the surface of the Moon and are
00:29:01
planning to launch their first manned mission into orbit next
00:29:04
year. But India's times a modern scientifically advanced space
00:29:07
faring nation may wind up being rather short lived. You see
00:29:12
Indian authorities are dumbing down the country's education
00:29:15
system.
00:29:16
They're cutting key scientific topics from the curriculum,
00:29:19
including the periodic table and evolution. Tim Mendham from
00:29:24
Australian Skeptics says the move is being pushed along by a
00:29:27
strong nationalist movement within the government in India.
00:29:30
There's a bit of a drive on to promote what they call Hindu.
00:29:33
Science, locally developed science that supposedly goes
00:29:37
back thousands of years to show that we don't need all this
00:29:40
stuff. We had it all before. In India, there's a suggestion that
00:29:44
what's happened now is that especially for 15 to 16 year old
00:29:47
students in high school, in secondary schools in India, in
00:29:50
their science classes, all references to evolution.
00:29:53
A periodic table, climate related topics have been cut
00:29:57
from textbooks. So kids who are studying biology at that level,
00:30:01
which is the general level of people doing science are not
00:30:04
being taught evolution, which is being criticized by saying not
00:30:06
teaching evolution in biology. It's like not using numbers in
00:30:09
mathematics. It's the basis of it, it's the core of it, it's
00:30:12
highly important.
00:30:14
So by having it cut out, it implies there's a certain bias
00:30:17
in what things are being presented, not just downplayed,
00:30:19
it's actually cut out of the textbooks has been taken and
00:30:23
have taken all these subjects out. The authorities claim that
00:30:26
the content is covered elsewhere and that it's difficult to
00:30:29
explain and they say it might be irrelevant anyway. Well, it's
00:30:32
not irrelevant.
00:30:33
Obviously, evolution is not irrelevant to biology in the
00:30:35
same way as the periodic table is not irrelevant to chemistry
00:30:38
and it's difficult. Well, that's up to the teachers, isn't it the
00:30:41
way you teach? You can teach evolution pretty
00:30:43
straightforward. You don't have to become a phd at high school
00:30:46
level and the content is covered elsewhere.
00:30:47
Well, that's hard to say because basically it means that kids who
00:30:50
go up to age 15, 16 and who don't choose to go into science
00:30:54
classes and not being taught their stuff. Hopefully it's
00:30:57
taught later on for the time being anyway. But that's only
00:30:59
for people who choose to do science. So the general public
00:31:02
is not going to hear about evolution, periodic tables,
00:31:05
climate change, energy sources, all sorts of things like that.
00:31:08
There is a general anti science pseudo science move that's going
00:31:12
on in India, whether it's in education, even at university
00:31:15
level, there are some very strange theories put forward
00:31:17
such as the Indian God with an elephant head on a man is
00:31:21
evidence of advanced surgery by Indians thousands of years ago
00:31:25
that all sorts of strange things that have been put forward in
00:31:29
Indian circles, often by people who should know a lot better get
00:31:32
a move on to try and stop this, but it's having a hard time.
00:31:36
So it is supported at the highest levels of politics.
00:31:38
Is this just one political party or is this across the board?
00:31:42
It's mainly Modi's party? Well, the claims are actually being
00:31:44
put forward as a general movement and it's definitely
00:31:46
being supported by Prime Minister for the last 10 years
00:31:50
and it's hurting India's development.
00:31:52
What does that do for India? It 's now the world's largest
00:31:55
country in terms of population. What's that? Going to do for the
00:31:58
development of the nation.
00:31:59
It's also a country that is pushing itself as an advanced
00:32:01
nation. It's got a huge university education resource.
00:32:04
It's got a lot of research they're trying to sort of push
00:32:07
through. But this is obviously one, it makes them look a bit
00:32:09
silly and two, it'd be raising people who really don't have a
00:32:12
broad enough understanding of what's going on.
00:32:14
That's Tim Mendham from Australian Skeptics and that's
00:32:33
the show for now. Spacetime is available every Monday,
00:32:37
Wednesday and Friday through Apple podcasts, itunes,
00:32:40
Stitcher, Google Podcast, pocket casts, Spotify, a cast Amazon
00:32:45
music bites dot com, Soundcloud, YouTube, your favorite podcast
00:32:50
download provider and from Space Time with Stewart Gary dot com.
00:32:54
Spacetime is also broadcast through the National Science
00:32:57
Foundation on Science Own radio and on both IHeart Radio and
00:33:01
Tune in radio.
00:33:02
And you can help to support our show by visiting the Spacetime
00:33:05
store for a range of promotional merchandizing goodies or by
00:33:09
becoming a Spacetime patron, which gives you access to triple
00:33:12
episode commercial, free versions of the show as well as
00:33:15
lots of bonus audio content, which doesn't go to air access
00:33:19
to our exclusive Facebook group and other rewards. Just go to
00:33:23
Space Time with Stewart Gary dot com for full details.
00:33:26
And if you want more Space Time, please check out our blog where
00:33:29
you'll find all the stuff we couldn't fit in the show as well
00:33:32
as heaps of images news stories, loads of videos and things on
00:33:36
the web. I find interesting or amusing. Just go to Space Time
00:33:39
with Stewart Gary dot tumblr dot com.
00:33:42
That's all one word and that's Tumblr without the E you can
00:33:46
also follow us through at Stuart Garry on Twitter at Space Time
00:33:50
with Stuart Garry on Instagram through our Space Time YouTube
00:33:53
channel and on Facebook, just go to Facebook dot com forward
00:33:57
slash Space Time with Stewart Gary and Spacetime is brought to
00:34:01
you in collaboration with Australian Sky and Telescope
00:34:03
Magazine. Your Window on the Universe.
00:34:06
You've been listening to Space Time with Stuart Garry. This has
00:34:10
been another quality podcast production from bites dot com.