SpaceTime with Stuart Gary - Your one-stop Space News Pod.
#astronomy #space #science #news #podcast #spacetime
Become a supporter of this podcast: https://www.spreaker.com/podcast/spacetime-with-stuart-gary--2458531/support.
00:00:00
STUART GARY: This is Space Time series 26 episode 87 for
00:00:03
broadcast on the 21st of July 2023. Coming up on Space Time,
00:00:09
the man on the moon gets his clock reset by 200 million
00:00:12
years. New clues about when plate tectonics began on planet
00:00:17
Earth and the final flight of Europe's workhorse rocket, the
00:00:21
Ariane Five, all that and more coming up on Space Time.
00:00:27
GENERIC: Welcome to Space Time with Stuart Garry.
00:00:46
STUART GARY: Scientists have reset the clock for craters on
00:00:49
the moon, meaning that parts of its surface those which
00:00:52
characterize the children's story. The man on the moon are
00:00:55
actually around 200 million years older than previously
00:00:58
thought.
00:00:59
The findings reported in the planetary science journal are
00:01:02
based on a coordinating and recalibration of two conflicting
00:01:06
systems of dating the surface of the moon. The new evaluation
00:01:10
shows that large parts of the lunar crust are actually around
00:01:13
200 million years older than had been previously thought,
00:01:16
allowing scientists to better clarify the sequence of events
00:01:19
in the evolution of the moon's surface these days.
00:01:23
Our moon is pretty geologically inactive. That means that the
00:01:27
craters from asteroids and comets which bombarded the moon
00:01:30
throughout its history to give it its appearance haven't been
00:01:32
eroded away. By time.
00:01:34
Of course, the Earth itself received a similar barrage
00:01:37
throughout time. But constant erosion and plate tectonics have
00:01:41
erased most of these impact features. Now, the standard way
00:01:45
of measuring the surface of any celestial body such as the moon
00:01:48
is a process called crater counting. Put simply the more
00:01:52
craters the older the surface.
00:01:54
But this actually gives a very definite result to that scene
00:01:58
when examining rocks from the Apollo missions, especially for
00:02:01
the light areas of the moon such as the highlands.
00:02:04
One of the study's authors, Professor Stephanie Werner from
00:02:06
the University Of Oslo has told the Goldschmidt Geochemistry
00:02:10
Conference in Lyon that her team decided to reconcile these
00:02:13
differences by correlating individually dated Apollo
00:02:16
samples to the number of craters in the sample sites surrounding
00:02:20
area in effect resetting the crater clock.
00:02:23
They also correlated them against spectroscopy data from
00:02:26
various moon missions, especially the Indian Chandra.
00:02:29
One mission to be sure which Apollo samples belongs to the
00:02:32
surface in which they counter uss. This time consuming task,
00:02:37
took almost a decade. But the authors found that by doing
00:02:40
this, they could resolve the discrepancy and push back the
00:02:43
edge of the surface of the moon for up to 200 million years.
00:02:47
For example, the age of the Irian Basin filled with the
00:02:50
lunar sea, the mare embry which is visible on the top left of
00:02:53
the moon and which was probably created by the impact of a giant
00:02:56
asteroid.
00:02:57
About the size of Sicily goes back from 3.9 billion years to
00:03:01
around 4.1 billion years ago. Of course, none of this changes.
00:03:05
The estimated age of the moon itself. It was formed 4.5
00:03:09
billion years ago when a Mars sized planet which we now call
00:03:12
thea slammed into the early proto Earth.
00:03:15
But what the new system of dating does is change the ages
00:03:18
of all areas on the moon's surface, not uniformly, but with
00:03:22
the oldest surfaces showing the greatest changes. Werner says
00:03:26
it's an important difference is it pushes back the date of the
00:03:29
late heavy bombardment epoch.
00:03:31
Now, the late heavy bombardment is a period in our solar
00:03:34
system's history which saw a massive increase in astro and
00:03:37
combat impacts on bodies in the inner solar system. It was most
00:03:41
likely caused by the outward planetary migration of the gas
00:03:44
giants, Jupiter and Saturn to their current orbital positions
00:03:48
as they migrated out, the gravitational perturbations
00:03:52
flung material around them towards the inner solar system.
00:03:55
What it means is the late heavier bombardment took place
00:03:58
before the more extensive volcanic activity which formed
00:04:01
the man in the moon patterns, the mare volcanic planes
00:04:04
including mare embry as this happened on the moon, the Earth
00:04:09
was almost certain to have also suffered a similar early
00:04:12
bombardment.
00:04:13
But because most of the Earth's evidence is now white, the moon
00:04:16
provides unique records of this early bombardment history. So
00:04:20
far, we've had three successful lunar sample return programs.
00:04:24
These were the American Apollo missions, the Russian lunar
00:04:28
missions and China's Changi mission by combining the latest
00:04:32
spacecraft observations with impact events recorded by lunar
00:04:35
rocks. Werner and colleagues have greatly pushed back the
00:04:38
records for the late heavy bombardment.
00:04:40
And that's important because this heavy bombardment period
00:04:43
must have affected the origin, early evolution of life on Earth
00:04:47
and potentially on other planets such as Mars as well. And of
00:04:51
course, bringing back rock samples from Jero Crater on Mars
00:04:54
will be the next giant leap forward in the search for signs
00:04:58
of ancient life on other planets in the solar system.
00:05:01
And also exactly when it happened if indeed it did, this
00:05:05
is Space Time still to come new clues about when plate tectonics
00:05:11
began on Earth. And we look at the final flight of Europe's
00:05:14
workhorse, the Ariane Five, all that and more still to come on
00:05:19
Space Time.
00:05:36
A new study claims Earth began plate tectonic activity and
00:05:40
subduction around 3.8 billion years ago. The findings reported
00:05:45
in the journal science advances challenges all previous studies
00:05:48
which suggest that plate tectonics began within 200
00:05:51
million years of the planet's creation following the fear
00:05:54
impact, which created the moon 4.5 billion years ago.
00:05:58
Earth is currently the only planet known to harbor life and
00:06:02
that is thanks in a large part to the operation of plate
00:06:05
tectonics which recycles critical biochemical elements
00:06:09
and maintains a planetary thermostat subduction. The
00:06:12
destructive force of plate tectonics that pushes one plate
00:06:16
beneath another is the most telltale sign of tectonics.
00:06:19
Great recycling program. But how far back in time can we really
00:06:24
trace evidence for plate tectonics? Did Earth plates
00:06:28
always function as they do today with subduction and surface
00:06:31
material recycling? Previous studies using numerical
00:06:35
geodynamic modeling argues that subduction and recycling were
00:06:39
operating from as early as around 4.3 billion years ago.
00:06:43
Now, since the Earth itself is only 4.5 billion years old. Such
00:06:47
a claim generally argues that plate tectonics were happening
00:06:50
almost from the very beginning. However, new geochemical
00:06:53
evidence from some of the world's oldest rocks found in
00:06:55
the remote lake regions of northern Canada paints a starkly
00:06:59
different picture of Earth's earliest history.
00:07:02
The new study shows no signs of surface material recycling at 4
00:07:06
billion years. And the earliest evidence of surface recycling in
00:07:10
the magma's dates back to just 3.8 billion years. The key to
00:07:14
all this is silicon and oxygen isotopes in granite rocks, they
00:07:19
act as traces for surface material recycling into magma's
00:07:22
on ancient Earth.
00:07:24
Seawater was saturated with silicon due to the lack of life
00:07:27
forms to consume it. Therefore, any heavy silicon materials from
00:07:31
the sea floor were recycled back into magma chambers by
00:07:34
subduction. Then heavy silicon isotopes could be detected in
00:07:38
granitic rock samples. One of the difficulties in applying
00:07:42
this technique to ancient rocks is identifying primary silicon
00:07:45
isotope composition.
00:07:47
That's because these rocks have been reworked by heat and
00:07:49
pressure repeatedly through Earth's history. And that's
00:07:53
where zircons come in. They're the most abundant dateable
00:07:56
material in Grenet rocks and conveniently, they're also
00:08:00
resistant to weathering and later alteration.
00:08:03
So they're really like tiny little chemical time capsules.
00:08:06
Applying ultra high precision analytical techniques to Zircon
00:08:10
can provide the most reliable constraints on whether the
00:08:13
detectable silicon isotope composition represents the
00:08:16
primary signature. The study proposed systematic screening
00:08:19
criteria for evaluating the data carefully evaluating Zircon
00:08:23
silicon and oxygen isotope signatures.
00:08:26
And the authors found an abundance of heavy silicon
00:08:29
signatures in the 4 billion year old rocks, which implies that
00:08:32
the oldest samples didn't undergo subduction. In other
00:08:35
words, no plate tectonics. However, given that these oldest
00:08:39
rocks are just from a single location, the lack of subduction
00:08:42
in that area doesn't mean plate tectonics wasn't going on
00:08:45
elsewhere on the planet.
00:08:47
Now, after careful filtering through the data also revealed a
00:08:50
distinct shift at 3.8 billion years in both silicon and oxygen
00:08:54
isotopes. And it's for this reason, based on the current
00:08:58
data, the study concluded a possible change in the Earth's
00:09:01
geo dynamics such as the onset of plate tectonics and
00:09:04
subduction probably occurred around 3.8 billion years ago.
00:09:09
This is Space Time still to come. We say farewell to the
00:09:14
Ariane Five as it undertakes its final mission. And later in the
00:09:18
science report, a new study blames the fishing industry for
00:09:22
most of the plastic pollution in our oceans. All that are more
00:09:26
still to come on Space Time.
00:09:44
It's the end of an era with the last ever launch of an Ariane
00:09:48
Five rocket, successfully placing two new
00:09:50
telecommunications satellites into space. Ariane Space Flight
00:09:55
V. 261 lifted off from the European Space Agency's
00:09:59
Spaceport in French Guiana carrying the 3408 Kg German
00:10:03
Aerospace Agency, Dlr Heinrich Herz experimental satellite and
00:10:08
the 3572 kg French Syracuse four B satellite into their
00:10:13
respective geostationary orbits.
00:10:19
GENERIC: This you said.
00:10:42
Syracuse Four B and Heinrich Hertz satellite blazing a trail
00:10:46
on board the last ever Ariane Five across the equatorial
00:10:50
skies. And we can hear the rumble of her as she flies over.
00:10:55
It's very impressive and we are 11 kilometers from the pattern.
00:10:59
The delay of the vibration is a bit amazing, just get tired of
00:11:05
it.
00:11:05
And he's telling us that the trajectory is nominal,
00:11:09
everything is going according to plan one minute and 56 seconds
00:11:15
into the launch of Ariane Five.
00:11:20
So the proper is working perfectly nominally as we see in
00:11:24
the space to boost our separation.
00:11:31
We have confirmation from the range operations manager.
00:11:35
That's absolutely amazing.
00:11:36
Those two boosters on the right and the left being jettisoned.
00:11:42
So they are providing 90% of the overall thrust. And so they have
00:11:47
been jettisoned, there are 240 tons each. The launcher on the
00:11:51
ground was 771 tons.
00:11:54
We don't need them anymore.
00:11:57
SPK_2: So everybody is completely nominal.
00:12:00
GENERIC: So the next step is the separation of the faring that's
00:12:03
coming up in about 10 seconds and separation there of the
00:12:06
faring is what it looks like.
00:12:10
So you have confirmation of separation of the faring.
00:12:14
STUART GARY: The flight was the 117th and final mission for
00:12:17
Europe's Ariane Five workhorse which first flew way back in
00:12:20
1996 during an illustrious 27 year career. The 52 m tall two
00:12:27
stage rocket carried some of the most advanced scientific
00:12:30
instruments including Esa's Comet hunting Rosetta mission,
00:12:34
the giant Esa Nasa James Webb Space telescope and Esa's Juice
00:12:38
mission to Jupiter.
00:12:39
And of course, there are also multiple ATV cargo ships
00:12:42
carrying fresh food and supplies to the International Space
00:12:46
Station. Unlike its predecessors, the Arians 123 and
00:12:50
four, which were all really a series of evolutions on the same
00:12:53
basic design. The Ariane Five was an all new launch system,
00:12:57
specially designed to carry far heavier payloads, 20 tons at a
00:13:01
low Earth orbit and almost 11 tons at a geostationary orbit.
00:13:05
Its replacement the Ariane Six is well behind schedule
00:13:09
originally slated to begin flying in 2020. The new launch
00:13:13
is now only reaching its final pre launch preparations. In
00:13:17
fact, only last month.
00:13:18
Ariane Space retracted the mobile gantry thereby revealing
00:13:22
the first Ariane Six launch vehicle on its launch pad ahead
00:13:25
of its first hot firing test of the core stage Vulcan 2.1
00:13:29
engine. The inaugural flight of the Ariane Six should take place
00:13:33
before the end of this year. No final date has been given the
00:13:38
Ariane Six builds heavily on the heritage of its Ariane Five
00:13:41
predecessor, but it will carry more payload for lower cost.
00:13:44
It'll fly more often and it'll be far more flexible. The Ariane
00:13:49
Five used two strap on solid rocket boosters to add its
00:13:52
launch. But the Ariane Six can carry either two or four of
00:13:56
these boosters thereby varying its payload capacity. As the
00:14:00
production line for the Ariane Five began to slow down to a
00:14:03
finish.
00:14:04
Arian Space were planning to rely more on Russian Soyuz
00:14:07
rockets to fill the gap until Ariane Six begins. But the
00:14:11
boycott of Russia following Moscow's invasion of Ukraine in
00:14:14
February last year, put an end to that program and of course
00:14:18
another setback hit in December when Ariane Space's next
00:14:22
generation Vega Sea Light launch vehicle failed during launch,
00:14:26
grounding future flights.
00:14:28
The Vegas Sea is based on one of the strap on boosters used by
00:14:32
the Ariane Six. This is Space Time and time. Now for another
00:14:53
brief look at some of the other stories making news in science
00:14:55
this week with the science report, a new study has found
00:14:59
that the world's oceans have changed color to become greener
00:15:02
over the past 20 years.
00:15:05
The findings reported in the journal nature may be a marker
00:15:08
of climate change affecting the planet's phytoplankton, a
00:15:11
photosynthesizing microbes which form the basis of the ocean's
00:15:14
food web. The researchers say any changes to the color of the
00:15:18
ocean would affect how light passes through the seawater,
00:15:21
which could itself have a significant effect on life
00:15:24
within the oceans.
00:15:26
Now, keeping with our nautical theme, a new study has found
00:15:30
that the fishing industry is responsible for most of the
00:15:33
plastic pollution found in our reefs. The findings reported in
00:15:37
the journal nature show that over 90% of reefs have plastic
00:15:40
pollution and debris in them.
00:15:42
Scientists found macro plastics things larger than five
00:15:46
centimeters accounted for 88% of the plastics found and these
00:15:50
levels were highest in deep reefs between 20 100 and 50 m
00:15:54
down. They found fishing lines and nets and discarded traps
00:15:58
make up most of that pollution and it doesn't end there.
00:16:02
Researchers also looked at some lakes, they found microplastics
00:16:06
in all 38 lakes and reservoirs in the 23 countries.
00:16:10
They tested that was part of an exercise which looked at the
00:16:14
amounts of plastics and microplastics polluting the
00:16:16
world's lakes for the first time. The findings reported in
00:16:20
the journal nature show that plastic fragments and even
00:16:23
fibers from washing clothes and packaging residues in freshwater
00:16:26
lakes and reservoirs are higher than those in the plastic guys
00:16:30
of the ocean, the so called plastic garbage patches.
00:16:33
What it all means is that plastics are the largest and
00:16:37
most harmful and persistent fraction of marine litter.
00:16:40
Accounting for at least 85% of total marine waste.
00:16:45
An estimated 14 million metric tons of plastics enters the
00:16:49
world's oceans every year. With estimates of over 170 trillion
00:16:53
plastic particles currently afloat in the world's oceans
00:16:56
wreaking havoc on livelihoods and ecosystems and destroying
00:17:00
wildlife on a massive scale. Worse still, estimates suggest
00:17:04
that number is expected to triple over the next 20 years.
00:17:10
People are now dying from a new fad doing the rounds of the
00:17:13
hippie communities across the New South Wales, northern
00:17:15
rivers, hinterlands behind Byron Bay. They're poisoning
00:17:19
themselves by consuming secretions harvested from the
00:17:23
back of an Amazonian tree frog. Tim Mendham from Australian
00:17:26
skeptics says the poisons can cause psychedelic experiences
00:17:30
but it can also kill. Yeah, this is a.
00:17:32
TIM MENDHAM: Bit of a cultish treatment experience if you
00:17:34
like, especially among sort of new agey type, old hippie type
00:17:39
personalities. If you like often they have ceremonies which all
00:17:42
sorts of different things are going on, they might be taking
00:17:44
some psychedelic drugs and that sort of thing to improve their
00:17:47
spiritual well being.
00:17:48
But also this thing that's cropped up fairly recently. It's
00:17:51
an old thing in South America in the Amazon rainforest of
00:17:54
scraping bit of sweat or even poison off the back of a
00:17:57
particularly virulent frog. It's the Amazonian tree frog and
00:18:02
using that liquid to put on your skin. Now, first of all, you
00:18:06
have to take a little stick and you sort of pierce holes in your
00:18:09
skin in a sort of a nice little dot pattern.
00:18:11
And then you insert this poison into those holes. The trouble is
00:18:14
it can have a really dangerous effect. Even in fact, it's been
00:18:17
known to kill people. It's part of a mind expanding, spiritual
00:18:20
enhancing event or technique.
00:18:22
Some people find it very, very interesting but it can cause all
00:18:25
sorts of conditions ranging from choking to extreme diarrhea,
00:18:29
headache, dizziness, all the usual things. And in some cases,
00:18:32
if someone had severe choking, they can actually be coughing
00:18:35
up. And in one particular case, recently someone broke their
00:18:38
esophagus and they died accordingly. Obviously their
00:18:41
throat swelled up.
00:18:42
They couldn't breathe, turned blue and by the time an
00:18:45
ambulance got there, it was too late. The trouble is all the
00:18:47
other people are there sort of having their little cultish
00:18:49
activities in this particular case, especially going on.
00:18:52
That's right. Yeah, they were doing practice and that sort of
00:18:55
thing and they figured, oh, no, he's just going through a
00:18:57
process of cleaning up anti to.
00:19:01
That's right. And that's the trouble. It went too far and he
00:19:04
died. And the weird thing was that one of the people there
00:19:06
told the animal people to get out of the way because they were
00:19:09
interfering with the man's aura, which I presume not many people
00:19:12
have heard before and they're trying to help someone save
00:19:14
their lives that they're interfering with their aura.
00:19:16
But obviously that might be a bit extreme. Other people were
00:19:19
more concerned and did try and look after him but too late. And
00:19:23
it's not the first, there's been several deaths from these frog
00:19:26
poisons.
00:19:26
These things have been going on for a while and the ones that
00:19:29
recently have been used that are currently going through an
00:19:31
inquest to find out there's a second one not that long ago as
00:19:33
well, where a woman who had been trained in how to apply this
00:19:38
Cambo frog poison died herself from it in much the same way.
00:19:42
It's pretty gruesome the way people die from this, they're
00:19:44
choking. They have extreme diarrhea, all sorts of horrible
00:19:48
things that happen to them. Not the most pleasant way to go.
00:19:50
STUART GARY: That's Tim Ende from Austrian skeptics and
00:20:09
that's the show for now. SpaceTime is available every
00:20:12
Monday, Wednesday and Friday through Apple podcasts, itunes,
00:20:16
Stitcher, Google Podcast, Pocket casts, Spotify, a Cast Amazon
00:20:21
music bites dot com. Soundcloud, YouTube, your favorite podcast
00:20:26
download provider and from Space Time with Stewart Gary dot com.
00:20:30
SpaceTime is also broadcast through the National Science
00:20:33
Foundation on Science Zone Radio and on both iheart Radio And
00:20:37
Tune in radio and you can help to support our show by visiting
00:20:41
the SpaceTime store for a range of promotional merchandizing
00:20:44
goodies or by becoming a SpaceTime patron, which gives
00:20:48
you access to triple episode commercial free versions of the
00:20:50
show as well as lots of bonus audio content, which doesn't go
00:20:54
to air access to our exclusive Facebook group and other
00:20:57
rewards, just go to Space Time with Stewart Gary dot com for
00:21:01
full details.
00:21:02
And if you want more Space Time, please check out our blog where
00:21:05
you'll find all the stuff we couldn't fit in the show as well
00:21:08
as heaps of images, news stories, loads of videos and
00:21:12
things on the web. I find interesting or amusing. Just go
00:21:15
to Space Time with Stewart Gary dot tumblr dot com.
00:21:18
That's all one word and that's Tumblr without the E you can
00:21:22
also follow us through at Stuart Garry on Twitter at Space Time
00:21:26
with Stewart Garry on Instagram through our Space Time YouTube
00:21:29
channel and on Facebook, just go to Facebook dot com forward
00:21:33
slash SpaceTime with Stewart Gary and SpaceTime is brought to
00:21:37
you in collaboration with Australian Sky and Telescope
00:21:40
Magazine. Your Window on the Universe.
00:21:43
GENERIC: You've been listening to Space Time with Stuart Garry.
00:21:46
This has been another quality podcast production from bitesz
00:21:49
dot com.