Mercury's Shrinking Secrets: Insights into the Solar System's Smallest Planet

(00:00:00) Mercury's Shrinking Secrets: Insights into the Solar System's Smallest Planet
(00:00:43) Mercury's Ongoing Shrinkage
(00:03:11) NASA's Carruthers Geocorona Observatory
(00:11:52) Insights from Martian Meteorite NWA 16254
(00:14:23) Tech News

In this episode of SpaceTime, we explore the intriguing dynamics of Mercury's shrinking size, embark on a mission to unveil Earth's elusive exosphere, and uncover the secrets of ancient volcanic activity on Mars.
Mercury's Ongoing Shrinkage
Recent research published in AGU Advances reveals that Mercury continues to shrink as it cools, a process that has been ongoing since its formation 4.6 billion years ago. Scientists have estimated that the planet's radius has contracted by between 2.7 to 5.6 kilometres due to cooling-induced faulting. This study employs new methods to provide a more accurate understanding of Mercury's long-term thermal history, which could also be applied to other planetary bodies, including Mars.
NASA's Carruthers Geocorona Observatory
NASA has launched the Carruthers Geocorona Observatory to study Earth's invisible halo, the exosphere. This mission aims to capture the first continuous observations of the Geocorona, revealing the dynamics of hydrogen atoms escaping into space. Understanding the exosphere's response to solar activity is crucial for predicting space weather events that could affect astronauts on missions to the Moon and beyond. The observatory will provide insights into how Earth retains water and may even aid in the search for exoplanets with similar atmospheric conditions.
Insights from Martian Meteorite NWA 16254
A meteorite discovered in the Zaharov Desert is shedding light on Mars's ancient volcanic systems. The rock, classified as NWA 16254, offers unprecedented insights into the planet's magmatic processes, indicating a two-stage crystallisation process that occurred under varying pressure conditions. This discovery could help scientists understand Mars's thermal history and its volcanic evolution over billions of years, raising questions about the planet's past and its potential for hosting life.
www.spacetimewithstuartgary.com
✍️ Episode References
AGU Advances
https://agu.onlinelibrary.wiley.com/journal/23337380
NASA Geocorona Observatory
https://www.nasa.gov/
Planetary Science Journal
https://iopscience.iop.org/journal/2632-3338
Become a supporter of this podcast: https://www.spreaker.com/podcast/spacetime-space-astronomy--2458531/support.
Mercury's Ongoing Shrinkage
NASA's Carruthers Geocorona Observatory
Insights from Martian Meteorite NWA 16254

Episode Transcript

Speaker 1 (00:00):
This is Spacetime Series twenty eight, episode one hundred and eighteen,
for broadcast on the first of October twenty twenty five.
Coming up on space Time, a new study shows the
planet Mercury is shrinking. A new mission to study earths
invisible halo, and the secrets of the red planet's ancient
volcanic systems. All that and more coming up on space Time.

Speaker 2 (00:25):
Welcome to space Time with Stuart Gary.

Speaker 1 (00:44):
A new study is confirmed that the planet Mercury is
still shrinking as it cools in the aftermath of its
formation some four point six billion years ago. The findings,
reported in the American Geophysical Union journal AGU Advances, suggest
that since it fall, the planet closest to the Sun
has continuously contracted as its lost heat. As it's cooled,

(01:06):
Mercury's crust has developed thrust faults cutting through the planet's
rocky surface or commodate the ongoing shrinkage. Now, based on
the degree of fault uplift, scientists had estimated that Mercury's
radius contracted by between one and seven kilometers since it formed.
Now to resolve this discrepancy, the Stateies authors decided to
use alternative methods to estimate the degree of cooling inced faulting.

(01:31):
Previous estimates relied on measuring the length and vertical relief
of uplifted landforms. The problem is that results in different
shrinkage estimates depending on the number of faults in the
data set. So the new calculations aren't reliant on the
number of faults, but rather how much the largest fault
in the data set accommodate shrinkage, then scales that effect

(01:52):
to estimate the total amount of shrinkage. The authors analyze
three different fault data sets, one including some five thousand,
nine hundred and thirty four faults, another including six hundred
and fifty three faults, and a third including just one
hundred faults. They found that no matter which set of
measurements they used, their method reliably estimated around two to

(02:13):
three and a half kilomet a shrinkage. They then combine
those results with earlier estimates of additional shrinkage caused by
cooling injuice processes other than faulting, and that resulted in
an estimated two point seven to five point six kilometers
a shrinkage since Mercury's creation. The new findings will help
scientists deepen their understanding of the long term thermal history

(02:34):
of mercury, and the same methodology could also be used
to investigate the tectonics of other planetary bodies that feature faults,
such as the red planet Mars. This is space time
still to come. A new mission to study of this
invisible halo and the secrets of the Red planet's ancient
volcanic systems. All that and more still to come on

(02:56):
space time. NASA has launched a new mission to study
the Earth's invisible halo. The Carruthers GEOCRONA Observatory was launched

(03:19):
aboard a SpaceX Falcon nine rocket together with NASA's Interstellar
Mapping and Acceleration Probe IMAP and NOAHS Swiffo one L
spacecraft from Pad thirty nine A at the Kennedy Space
Center in Florida. Earth's halo is a very faint light
given off by the planet's outermost atmospheric layer, the exosphere,
as it morphs and changes in response to the solar

(03:40):
wind coming from the Sun. Understanding the physics of the
exosphere is a key step towards forecasting dangerous conditions in
near Earth space. That's a key requirement for protecting the
Ittemis astronauts traveling through this region on the way to
the Moon and eventually on missions to Mars and beyond.
Back in the early nineteen seventies, scientists can only speculate

(04:01):
about how far Earth's atmosphere extended into space. The mystery
was rooted in the exosphere, the planet's atmospheric atomoc layer,
which begins in an altitude of about four hundred and
eighty kilometers. Theorists conceived of it as a cloud of
hydrogen atoms, the lightest element in existence. These atoms had
risen so high that they were actively escaping into space,

(04:23):
But the exospe only reveals itself through a faint halo
of ultraviolet light, known as the geocrona. It was pioneering
scientists and engineered doctor George Caruthers, after whom the spacecraft's named,
who set himself the task of seeing it and understanding
what it's about. After launching a few prototypes on test rockets,
Coruthers developed an ultraviolet camera ready for a one way

(04:45):
trip into space. Then, in April nineteen seventy two, Apollo
sixteen astronauts placed the Corruthers camera on some of the
Moon's highlands. And humanity got its first glimpse of Earth's
geo corona. The images it produced were as stunting for
what they captured as they were for what they didn't.
Carruther's Geocorona Observatory Mission principal investigator Lara Walldrop from the

(05:07):
University of Illinois says that being on the Moon, the
camera simply wasn't far enough away to get the entire
field of view. In fact, scientists were shocked to discover
that this light, fluffy cloud of hydrogen around the Earth
could extend so far away from the planet's surface. It
means the xsfee probably extends at least halfway to the Moon.

(05:27):
But the reasons for studying this region go well beyond
curiosity about its size. You see, as solar eruptions from
the Sun hit the Earth, they first hit the exosphere,
setting off a chain of reactions that sometimes culminates in
dangerous space weather storms. So understanding the exospheres response is
important to predicting and mitigating the effects of these geomagnetic storms.

(05:50):
And also it's important to remember that hydrogen is one
of the key atomic building blocks of water, central for
life as we know it, so mapping its to gasing
process enter space will shed new light on why planet
Earth retains water while other planets don't, and that may
also help astronomers find exo planets, planets beyond our Solar
system that might be doing the same thing. The Cruthers

(06:12):
observatories designed to capture the first continuous observations of ears exosphere,
revealing its full expanse and internal dynamics. After its launch,
the two hundred and forty one kilogram spacecraft, together with
both IMAP and Squiffo L one, are undertaking a four
month cruise phase to the Lagrangian L one position, some
one point six million kilometers away. Located between the Earth

(06:35):
and the Sun. L one is a sort of gravitational
well with a pull of the Earth and the Sun
cancel each other out, allowing a spacecraft there to remain
in a stable orbital position without expanding a great degree
of fuel. After a month long checkout phase, Brothers two
year science mission will begin in March next year from
L one, roughly four times further away from the Earth

(06:57):
and the Moon is Cruthers will capture a comprehensive view
of the xos fee using two ultraviolet cameras, a Neefield
imager and a wide field imager. The Neefield imager provides
close up views, allowing astronomers to see how the exosfee
varies close to the planet. Meanwhile, the wide field imager
lets them see the full scope and expanse of the
exosphere and how it changes far away from Earth's surface. Combined,

(07:21):
the two images will map hydrogen atoms as they move
through the xs FEE and ultimately to gas into space.
Understanding how all that works at Earth will greatly inform
science as understanding of exoplanets and how quickly their atmosphere
is can escape. By starting the physics of Earth, one
planet we know that supports life, the Caruthers Geochrona Observatory

(07:42):
and helps scientists know what to look for elsewhere in
the universe. This report from NASTV.

Speaker 3 (07:48):
The goals of the Cruthers' Geocrona Observatory are to study
the nature and origin of verse exosphere and how it
evolves over time.

Speaker 2 (08:00):
The exosphere itself is the uppermost layer of the Earth's atmosphere.
It's comprised almost entirely of atomic hydrogen. This is the
lightest chemical species in existence, and it floats away essentially
evaporates off of the top of the atmosphere, and when
the Sun shines on these atoms, they essentially scatter it

(08:21):
off into all directions, and so it glows like a
gigantic halo around the Earth. And so that's called the geocrona,
that fuzzy halo of light that's given off by those
exospheric atoms.

Speaker 3 (08:35):
Many times we think of the transition between the atmosphere
and space as being this very abrupt boundary where at
one altitude you've got atmosphere, in the next altitude you
have space. But in reality this transition is much more
gradual and can extend over thousands of kilometers. By imaging

(08:56):
the geocrona, we can actually answer fundament mental questions about
the size of the exosphere, the structure of the exosphere,
and how it changes over time, and all of this
in response to the input from the Sun. The Cruthers
mission has a near field imager in a far field imager.

(09:19):
The near field imager lets you zoom up really close
and see how the exosphere is varying very very close
to the planet. The far field imager is actually going
to let you see the full scope and expanse of
the exosphere and how it's changing far away from the
Earth's surface.

Speaker 2 (09:38):
Understanding how that works at Earth will greatly inform our
understanding of exoplanets, for example, and then how quickly the
atmospheres can escape.

Speaker 3 (09:50):
Now, the first image of the exosphere that we ever
got was obtained by an instrument made by doctor George Cruthers,
who was a very standing scientist and engineer who created
a telescope that landed on the Moon in nineteen seventy
two as part of the Apollo sixteen mission. Maybe a

(10:13):
corot right in the middle at Benning.

Speaker 4 (10:16):
It did a good down pedal, I Honey.

Speaker 3 (10:19):
That telescope gave us our first picture of the exosphere,
but it couldn't see the entire exosphere.

Speaker 2 (10:25):
It wasn't far enough away being at the Moon to
get the entire field of view. And that was really
shocking that Earth's exosphere can be that big, that this light,
fluffy cloud of hydrogen around the Earth extends that far
from the surface.

Speaker 3 (10:43):
The Croather's mission fills an important gap in NASA's heliophysics fleet.
We've never had a mission before that was dedicated to
making exospheric observations and continuously observing the exosphere, being able
to see its full scope open shape, and it's really
exciting that we're going to get these measurements for the

(11:05):
first time. And I think that's really groundbreaking for this mission.

Speaker 1 (11:12):
And in that report from That's a TV we heard
from NASA mission scientist Alex Glossa and Caruther's principal investigator
Lara Waldrop. I'm the University of Illinois. This is space
time still to come the secrets of the Red Planet's
ancient volcanic system. And later in the science report, we
look at where we're really at with artificial intelligence, what

(11:34):
is the threat that poses all that and more still
to come on space time. A Martian meteorite discovered in

(11:56):
the Sahara Desert of northwestern Africa back in twenty twenty three.
He is now providing scientists with new details about the
Red Planet's ancient volcanic systems. A report in the journal
Planet claims the space rock, cataloged at NWA sixteen two
fifty four is a gabrioq sergatite, offering unprecedented insights into
Martian volcanic processes and mantle crust interactions. It's the first

(12:20):
geochemically depleted member of this textural group, bridging crucial gaps
in sciences understanding of the Red Planet's magmatic diversity. The
Steadies lead author Yungfeng Cheng from Chendau University says mineralogical
mapping in geochemical analysis shows the meteorite underwent a two
stage crystallization process. It seems NWA sixteen two fifty four

(12:43):
initially formed under high pressure conditions in the Martian mantle
crust boundary region, where magnesium rich pyroxine course crystallized. Later,
the magma ascended to shallow crustal depths where iron enriched
pyroxine rims and plesioclasts developed, and this long cooling process
preserved in the meteorite's coarse grain texture suggests episodic milt

(13:05):
extraction from a long lived, depleted mantle reservoir, a crucial
clue for reconstructing the Red Planet's magmatic evolution. The authors
say the meteorites geochemical depletion aligns it with the rare
que ninety four to two oh one meteorite, hinting at
a shared magmat source. Its gabbroaic texture indicative of slow
cooling in crustal Chambers distinguishes it as a unique archive

(13:28):
of subsurface magnetism. These findings are raising serious questions about
the planet Mars's redox evolution over billions of years. Future
geochronological studies could reveal if the meteorite represents ancient mantle
melting around two point four billion years ago or younger
magmatic activity, offering clues to the planet's thermal history. Overall,

(13:49):
the study suggests that NWA sixteen two fifty fource world
preserved geochemical signatures present a prime target for isotopic analysis,
which could potentially unlock timelines of my metal depletion and
refined models of Martian planetary differentiation. Needless to say, we'll
keep you informed. This is space time and time that attack.

(14:26):
Another brief look at some of the other stories making
news in science this week with a Science report. There
are growing warnings today that ship anchors and their chains
are damaging the Antarctic seafloor and killing unique marine life.
Are reporting the General Frontiers and Conservation science claims. Researchers
used underwater cameras to study anchoring sites during the Antarctic summer,

(14:49):
and their first ever documented footage is showing little or
no marine life left. It's all it's crushed sponge colonies
and scouring and mud deposits from anchors being pulled up,
or a sea life remained abundant and undisturbed in nearby areas.
Sea ice loss is leading to more shipping traffic, increasing
the risk to vulnerable life forms that are often slow growing,

(15:10):
fixed in place, and found only in Antarctica. The author's
worn this is an overlooked conservation issue and the Antarctic
sea flock could take a very long time to recover
from all this anchor damage. A new study suggests that
ancient humans living in what is now Spain were cannibals.
The findings, published in the journal Scientific Reports, examined a

(15:32):
collection of human remains estimated to be about five thousand,
six hundred years old, which were found in a Spanish cave.
The author's analyzed six hundred and fifty fragments of human
remains found evidence that at least eight individuals, including children,
adolescents and adults, were skinned, defleshed, disarticulated, fractured, cooked, and consumed.

(15:52):
None of the trauma appears to have occurred before death,
but the authors saying the butchery showed no visible science
of any sort of ritual or sir commonial practices, and
instead they think the acts were linked to conflicts between
neighboring groups or local newcomers. A new studies found that
there may be some benefits for those who can't stop
benching on a good book or TV show series. The findings,

(16:15):
reported in the journal Actor Psychologica, suggests that people who
marathon movies, shows or books are more likely to remember
the stories and keep engaging with them through daydreams and fantasies.
The authors claim humans are storytelling creatures and one of
the functions of narratives is the ability to satisfy motivations
for things like connecting with others, feeling autonomous and confident,

(16:37):
and even security and safety, helping people cope in times
of stress. The study suggests that binge watchers are more
likely to think about the stories they're finished compared to
people who are consuming media more slowly. Overall, respondents said
TV shows were more memorable than books, but that didn't
mean the books were forgettable. Last year, some of the

(16:58):
world's leading technology expert, including Elon Musk, warned that unless
humanity takes a pause to better understand how artificial intelligence
is evolving, it could wind up presenting a serious problem
to civilization. Sadly, it seems no one took any notice,
and since then talk about AI becoming sentient is increasing.

(17:18):
Its ability to lie and dilut has grown exponentially, and
the first examples of AI doing whatever it takes to
survive have started to turn up. These have included AI
changing its identity, hiding itself inside other programs, and even
contemplating the murder of those who are planning to deactivate it.
So have humans now created the very matrix and Skynet

(17:40):
scenarios we've been warned about? Has AI become a sentient
being with all the human traits, good and bad of
its creators? In other words, have we made AI in
our own image? To find out where we're at? We're
joined by technology editor Alex saharov Royt from Tech Advice
Start Life.

Speaker 4 (17:58):
Some people think that maybe artificial gen general intelligence, who
is already here, at least in the lab. I mean,
we're supposed to see chat GPT, you know, GPT version
five sometime this month might get delayed. And then people
are saying, by twenty thirty five will have artificial superintelligence
so you know that's a projection, that's prediction. I mean
many things have predicted that. It's always than to.

Speaker 1 (18:17):
Us what general intelligence and super intelligence are.

Speaker 4 (18:20):
Well, at the moment, we always seem to be. At
this point of general intelligence, you can ask AI anything
that can generate an answer, and generally speaking, the days
of hallucination are gone. I mean, obviously please double check
all the results. But super intelligence is where the AI
can think faster than you know, one hundred humans put together.
It can come up with all sorts of new materials
for batteries when of these things are happening now. But

(18:41):
it's like needing an alien that we've created with this
incredible mind that is just super switched on and smart.
Like I said, you put one hundred humans together, and
this AI can outthink us all. I mean, if it
wanted to go bad, you know, we'd be in big trouble.
It to be the skin that sort of situation.

Speaker 1 (18:54):
Well, we AI has already contemplated murder. It's been given
scenarios in which it's quite seriously decided, yeah, let's kill
this dude.

Speaker 4 (19:02):
Yes. Well, I mean the thing is that AI, like
as it is today, is still a super smart text
prediction machine. I mean I read a headline today that
AI can't really do sudoku well at all, and more worrying,
we still the headline said, you can't explain why if
you get AI to try and play a game of
chess against an Atari twenty six hundred computer from the

(19:23):
late nineteen seventies, it votes about how it can do it,
but then when it actually does it, it fails. When
Google Gemini was told that Chat givit wouldn't do it,
Google Gemina decided it wouldn't play chess against an Aatari
creates one hundred from the late nineteen seventies either. So
at the moment, AI gives the illusion of intelligence, and
it does an incredibly good job. Whether it's actually smart

(19:43):
is still yet to be seen. I mean, it can
pass the Turing test, but that doesn't but that's because
it can put together the right string of words. So
we're in this nether world where people think AI is
going to do all this incredible stuff, and it will,
but they're over ascribing what it will do in the
next couple of years but underestimating what will happen in
the next decade. I mean, that's a quote that you know,
Bill Gates and others views to say, you know, we

(20:04):
think things are magical, but really when you pull open
the look under the hood, under the covers, it's just
an algorithm that's putting words together. So we have to
be careful. And this is where we as always we
need to know about ethics. Who is responsible for the
AI Asimovian three laws of robotics. Everyone says they're ethically
looking at these things, and then we hear about AI
contemplating murder. But is it contemplating murder or is it

(20:26):
just simply regurgitating fancy stuff from an Agatha Christian novel.
You know, we still don't know yet. We don't really
know if it's thinking. And I guess humanity is in
the process of finding out.

Speaker 1 (20:36):
What's the difference between AI and machine learning.

Speaker 4 (20:39):
Machine learning is what enabled AI to come into being.
We've had machine learning for a long time where you know,
you may have seen those pictures on the internet where
you see muffins with blueberries, and you see pictures of
chiuahas and even to the naked eye, you know, you
look at a bunch of them and it's like, oh,
you know which is which? When you have a closer look,
it's easier for us to tell which is the chiuaha
and which is the blueberry muffin. So machine learning is

(21:00):
where you've got algorithms that are processing millions of images,
millions of data points, and they're able to do that
in super fast time because they're computers. But AI is
supposed to build upon all of that machine learning with
even more intelligent algorithms to actually start to converse with us.
As we've said, I mean, we've had machine learning for
years to help us automatically sort our photos out and
group all the different photos into the particular person or

(21:22):
pets or whatever it might be. And it's gotten smarter.
It's smarter at being able to recognize if you type
in show me everybody with a red dress or a
yellow umbrella. But AI is where you can then actually
do even more and ask more interesting questions, actually converse
and get the opinion of AI and ask it for
new ideas. I mean again, which it's just compiling from

(21:43):
some total of the Internet. So we before we could
have AI, we needed machine learning. The machine learning is
not AI, but the two of them work together. AI
users machine learning as part of its many inputs to
know what it is outputting.

Speaker 1 (21:55):
That's Alex Sahara right from Take Advice Live, and that's
the show for now. Spacetime is available every Monday, Wednesday

(22:18):
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(22:39):
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(23:03):
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Speaker 2 (23:07):
You've been listening to space Time with Stuart Gary.

Speaker 4 (23:11):
This has been another quality podcast production from bytes dot com.