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Psyche to the core...
South Pole more of a problem I think:

Elon, China, Russia gets off this fracking planet ASAP !!!

WE can't even build a wall while fighting.

Bob... Ninja Assimilated
"The Morning Light, No sensation to compare to this, suspended animation, state of bliss, I keep my eyes on the circling sky, tongue tied and twisted just and Earth Bound Martian I" Learning to Fly Pink Floyd [Video:]
The Unsolved Mystery of the Earth Blobs

Published on 27 February 2019

Researchers peering into Earth’s interior found two continent-sized structures that upend our picture of the mantle. What could their existence mean for us back on Earth’s surface?

[Image: earth-layers-cutaway-crust-mantle-core-c...00x600.png]

By Jenessa Duncombe 27 February 2019

What lies below? A cutaway of Earth down to the liquid core shows the swirling mantle rock (dark blue). Made from a numerical convection model, the image shows mysterious structures underneath the Pacific Ocean that some researchers believe hold the clue to unlocking mysteries of Earth’s past (light blue). Credit: Mingming Li/Arizona State University

Some 2,000 kilometers beneath our feet, there are enormous masses of hot mantle material that have baffled scientists for the last 4 decades.
The blobs, as some scientists have taken to calling them, are the length of continents and stretch 100 times higher than Mount Everest. They sit at the bottom of Earth’s rocky mantle above the molten outer core, a place so deep that Earth’s elements are squeezed beyond recognition. The blobs are made of rock, just like the rest of the mantle, but they may be hotter and heavier and hold a key to unlocking the story of Earth’s past.
Scientists first spotted the blobs in the late 1970s. Researchers had just invented a new way to peer inside Earth: seismic tomography. When an earthquake shakes the planet, it lets out waves of energy in all directions. Scientists track those waves when they reach the surface and calculate where they came from. By looking at the travel times of waves from many earthquakes, taken from thousands of instruments around the globe, scientists can reverse engineer a picture of Earth’s interior. The process is similar to a doctor using an ultrasound device to image a fetus in the womb.

[Image: sanne-cottaar-earth-globe-spinning-blobs-llsvp.gif]

“Ultimately, a lot of people believe plate tectonics are one of the reasons why we have life on Earth,” said geophysicist Harriet Lau at Harvard University. Scientists believe these blobs play a role in many of the processes of the deep Earth, including plate tectonics and volcanism.
Once researchers began to form a picture of inner Earth, they started to see things they never imagined.
“It was very clear in those models from the get-go that at the bottom of Earth’s mantle, nearly halfway to the center, there were these huge zones where the waves traveled more slowly,” said Ed Garnero, professor of Earth and space exploration at Arizona State University.
The slow-wave velocity zones are concentrated in two locations: One lies under the Pacific Ocean, and the other sits under Africa and part of the Atlantic Ocean. They appeared like “massive mountains on the core-mantle boundary,” said seismologist Sanne Cottaar from the University of Cambridge. Other researchers describe them as conical pits of gravel sitting “all on top of each other” or like giant sand piles. The blobs are so large that if they sat on Earth’s surface, the International Space Station would need to navigate around them.
“They’re basically unmissable,” said seismologist Karin Sigloch at the University of Oxford. “They just show up on everybody’s pictures.”
There is little doubt that the blobs exist, yet scientists have no idea what they are. A recent paper said the blobs “remain enigmatic.” Scientists can’t even decide on what to call them. They go by many names, most commonly LLSVP, which stands for large low shear velocity provinces.

[Image: earth-blobs-north-south-poles-llsvp-3d.png]
The blobs, seen from the (a) North and (b) South Poles. The two-toned structures show the shapes of the blob based on the agreement of five different models (brown) and three different models (tan). Credit: Cottaar and Lekic, 2016,

Part of the reason for this mystery is what Earth scientists have always struggled with: They will never be able to visit the inside of Earth. “We know less about what’s deep below our feet than the surface of the Sun or the Moon or Mars,” said University College London researcher Paula Koelemeijer. Scientists are constantly trying to come up with new ways to peek inside Earth indirectly.
Fortunately, technological advancements in sensing miniscule wobbles within Earth, as well as efforts to outfit more locations with instruments, have been propelling the field forward. Several recent studies in cutting-edge techniques are bringing new insights to the table.

Are You Dense or What?

Much of the blobs’ mystery hinges on pinpointing what they are made of. Most seismic readings cannot determine the density of the material because changes in wave velocity depend on multiple factors, such as rock composition. Not knowing the density leaves many “doors open,” said mineral physicist Dan Shim from Arizona State University.
Shim has seen the debate about the blobs’ material raging since he was a graduate student in the 1990s. “I’ve watched this whole controversy throughout my career,” he said. Researchers have argued back and forth about whether the masses are made of dense piles of chemically unique rock or bouncy lava lamp plumes that are headed for the crust above.
Researchers speculate that the blobs may feed hot spot volcanoes, which form ocean island chains like Hawaii. And other scientists wonder if the blobs could have fueled supervolcanoes in the past, potentially contributing to Earth’s biggest extinction events. But Shim said that until the density of the blobs is understood, “we cannot go to the next level of questions.”

[Image: kilauea-volcano-hawaii-eruption-hotspot-blobs-llsvp.jpg]

Two recent studies, which found a way to measure density without traditional seismic methods, suggest a more complex view than before.  The Kīlauea volcano on the Big Island in Hawaii comes from hot spot volcanism, which scientists believe could be linked to the blobs. Credit:

[b]Earth Doing the Wave[/b]

Twice a day, Earth’s crust rises and falls with the tides. Although we’re more familiar with ocean tides, the solid Earth experiences the same forces as our oceans. As the Sun and the Moon pull on Earth, the entire planet flexes and stretches. In some places, the surface of Earth rises and falls by as much as 40 centimeters.

Scientists can track this movement using highly sensitive GPS measurements. A group of researchers led by Linguo Yuan at Academia Sinica in Taiwan analyzed measurements from GPS stations across the globe over 16 years and found that the Earth tide wasn’t what they expected: It seemed to be off-kilter just above where the blobs were located. The tides, they wrote in their 2013 paper, “provide significant information on the solid Earth’s deeper interior.”

Harriet Lau, a postdoctoral researcher at Harvard University, heard about Yuan’s work and saw an opportunity with the global data set. “It just so happens that body tides, or solid Earth tides, are very sensitive to density structure,” she said. These tides could fill in the knowledge gap that traveling waves used in seismic tomography could not.
Lau created dozens of models to explain the skewed Earth tides and compared them with Yuan’s data. She found that the models that fit the real-world data the best were those with blobs denser than the surrounding mantle. These findings, published in Nature in 2017, argued that the blobs have some sort of “compositional differences” than the rest of the mantle.
Meanwhile, another study suggested the opposite of what Lau’s study found.
Paula Koelemeijer began studying normal mode oscillations as a graduate student in 2008. “At the time, not many people were using them,” she said, despite the fact that they are a “very powerful way of thinking about the Earth.” Normal modes reveal details that more conventional seismic methods miss but are “difficult to develop an intuition for,” she said.

Many seismologists analyze waves coming out of Earth, but not all waves act alike. The images that map Earth’s interior use what’s called body waves. Similar to sound waves that travel through the atmosphere from someone’s mouth to another person’s ear across the room, these waves travel through Earth from one place to the next.
But there are certain kinds of waves that do not travel as much as they vibrate. This type of wave is called a standing wave, and it’s the type that shudders a violin string. “When you’re thinking of a standing wave, you’re looking at the whole resonating at the same time,” said Koelemeijer. “Like, it’s a bell that’s been hit and it’s vibrating as a whole.” Earthquakes trigger both types of waves, and seismometers detect them at the surface.
In Koelemeijer’s recent study, she picked a type of normal modes called Stoneley modes that vibrate depending on the density of the blobs. Her team analyzed records of ground movement in the days following large-magnitude earthquakes, looking for the low-frequency vibrations of standing waves. Comparing their results with models, they found that the blobs must be less dense than the surrounding mantle to explain several constraints, like the shape of the core.

When asked how the two studies reconcile, the researchers suggested that both papers could be correct.
“One way to perhaps reconcile Harriet Lau and my work is that this dense material is not distributed over a very large depth range,” Koelemeijer explained. Perhaps the blobs are densest in a sliver right next to the core, a detail that Koelemeijer could not rule out in her analysis. Lau echoed this suggestion. “I’m not actually worried at all about this seeming contradiction,” she said. The results simply help them “fine-tune” their conclusions, she said.

Very 3-D

[b]When seismologist Ed Garnero’s wife was pregnant with twins in 2002, he remembers going to the doctor for an ultrasound. Despite the new 3-D imaging technology, he said the low-resolution images on the screen were off-putting. “It looked like the brains were floating off to the side. It was really weird,” he said.
In seismic tomography, researchers deal with similar problems. The blobs received their nickname partly because of their soft, lump-like shape in seismic tomography maps. But what if their structure was actually more delicate? And could knowing the shape of the blobs better help researchers constrain their density?

Last December, doctoral student Maria Tsekhmistrenko from the University of Oxford presented some of the most revealing images of the structures to date. At a session at AGU’s Fall Meeting, Tsekhmistrenko showed her seismic tomography maps of about half of the blob under Africa. The images come from an extensive seismometer project that deployed sensors on the ocean floor around Madagascar.

Using a collection of different types of waves, Tsekhmistrenko revealed the jagged and angled sides of the blob and its plumes above it, showing very little of the softness suggested by earlier tomography maps. Taken together, the whole structure looks like a tree that branches up to hot spot volcanoes at the surface, said Tsekhmistrenko’s adviser, Karin Sigloch.
[b][Image: maria-tsekhmistrenko-africa-atlantic-blo...eeting.png][/b]

At first, Tsekhmistrenko said that they didn’t believe what they saw. “We worried that something was wrong with my data,” she said. Then she realized they were correct, even though “it looks different than expected.”
Very 3-D,” she added.
Garnero, who saw the presentation, said that it was “the best Earth interior imaging presentation I’ve seen at AGU.” He added that scientists who study the movement of the inner Earth, called geodynamicists, may be excited to get their hands on Tsekhmistrenko’s images.
“The slope of that structure turns out to be hugely important in constraining its density,” he said. “That’s really important for dynamicists.” Tsekhmistrenko has already heard from one geodynamicist planning to simulate the structures in a future model.
Seismic tomography image of a portion of the African blob and the mantle plumes coming off of it (left). The blob, called LLSVP, sits at the base of the mantle, and slow-wave velocity regions above the blob could indicate plumes or upwelling. A simplified image of the structures is shown on the right. Credit: Maria Tsekhmistrenko

[Image: maria-tsekhmistrenko-mantle-plumes-evolu...eeting.png]Scientists’ shifting ideas of what mantle plumes may look like, through several examples in the literature (Morgan, 1971,; Foulger et al., 2000,; Torsvik et al., 2010,; French and Romanowicz, 2015, Credit: Maria Tsekhmistrenko
Looking Inward
Despite critical advances in seismology, the quest to understand the blobs is “an inherently interdisciplinary problem,” said geologist Ved Lekic of the University of Maryland.

Mineral physicists, for example, measure how waves travel through rocks under extraordinary pressures to improve seismology models. Geochemists scour Earth to collect rocks from volcanoes, looking for clues of unique chemical reservoirs that could be linked to the blobs. And modelers construct intricate webs of code to evolve the mantle over billions of years, simulating how the blobs came to form.
Whatever the answer may be, peering under Earth’s crust may give researchers a way to contemplate our earliest beginnings. “These questions are very romantic in some ways,” said Harriet Lau. “I’m so inspired by questions that go to the root of existence and the universe.”
Earth is the only planet known to contain plate tectonics, and recent research has suggested that tectonics may help sustain life by delivering a steady stream of nutrients, like nitrogen and phosphorus, to the surface. And yet researchers aren’t sure what causes plate tectonic movement, let alone the blobs.

“I think that their real fundamental and philosophical appeal is their mystery,” said Lekic. “They’re among the largest things inside the Earth, and yet we literally don’t know what they are, where they came from, how long they’ve been around, or what they do.”
Ultimately, the road to uncovering the mysteries may be long, said Garnero. “This is a slow-motion discovery, it’s a community thing,” said Garnero, who has worked on the blobs for the last 15 years.
Lau, who plans to study the blobs as she begins her professorship at the University of California, Berkeley, later this year, said she isn’t fazed by the mystery. “I think science is incremental, and that’s why, for example, Paula Koelemeijer’s results didn’t particularly faze me,” she said. “I was actually more excited rather than anything else.”
—Jenessa Duncombe (@jrdscience), News Writing and Production Intern
Citation: Duncombe, J. (2019), The unsolved mystery of the Earth blobs, Eos, 100, Published on 27 February 2019.

"The Morning Light, No sensation to compare to this, suspended animation, state of bliss, I keep my eyes on the circling sky, tongue tied and twisted just and Earth Bound Martian I" Learning to Fly Pink Floyd [Video:]
NOVEMBER 6, 2019
Researcher makes the heart of Mars speak
[Image: uclouvainres.jpg]In 2020 the ExoMars mission will send a platform with the LaRa, a 100% Belgian-made instrument, supervised by UCLouvain researcher Véronique Dehant Credit: UCLouvain
For 20 years, Véronique Dehant, a space scientist at University of Louvain (UCLouvain) and the Royal Observatory of Belgium, has been working on understanding the Earth's core. In a few months, she will be able to complete her research by studying the heart of Mars, thanks to the ExoMars mission. Its purpose is to collect Martian radio science data and analyse the planet's rotation in order to better understand the red planet's innards and thus determine whether life is feasible on Mars. In the end, for Véronique Dehant, "This UCLouvain research is one more brick in the wall of understanding outer space."

[b]A bit of space history[/b]
For a planet to be habitable, it needs water on its surface. Previous space missions have demonstrated that there was water on Mars and that there is none today. Another essential fact about the red planet: its magnetic field is now extinct (which makes Mars uninhabitable—Earth's magnetic field and atmosphere protect us from radiation and the solar wind eroding our atmosphere). To understand this loss of atmosphere, one solution is to study the heart of Mars.
To obtain a magnetic field, movement in the planetary core's fluid part (conductive liquid core) is required. Understanding the nature of Mars's core will determine where the planet is in its evolution and even whether a magnetic field could one day be recreated—an essential condition for living on the red planet.
[b]Mars platform and robot[/b]
In concrete terms, on 25 July 2020 the ExoMars mission, led jointly by the European Space Agency (ESA) and the Russian Space Agency (ROSCOSMOS), will send a platform and a robot to the red planet:
  • The robot will collect subsoil samples (by drilling a few meters). Being a one-plate planet, its surface is not recycled (like Earth's): all of its history is engraved on its surface ... a treasure trove of information for scientists, who can delve into the history of Mars and the solar system.

  • As for the platform, it will house two European instruments, including one developed in Belgium, the Lander Radioscience (LaRa), which Véronique Dehant is responsible for. Its goal is to determine whether Mars's core is liquid or solid. Since planetary cores are physically inaccessible, scientists will use electromagnetic signals sent from Earth to LaRa and back (thanks to antennas designed at UCLouvain). The analysis of these signals will make it possible to understand the rotations and orientation of Mars and, ultimately, the nature of the red planet's core.

Explore further
Scientists explore outback as testbed for Mars

NOVEMBER 6, 2019
132 grams to communicate with Mars
[Image: 132gramstoco.jpg]On behalf of the ESA, UCLouvain has developed antennas for the LaRa instrument that will go to Mars in 2020 to study the red planet's habitability. The originality of UCLouvain's concept: the antennas are produced from a single block of aluminium to achieve lightness (132g!), miniaturisation (hand-sized) and great resistance (particularly to day-night temperature variations of more than 200° C). Credit: UCLouvain
Dust storms, ionising cosmic radiation, extreme cold at night ... Mars is not very hospitable! It's for these extreme conditions that the research team of Christophe Craeye, a professor at the UCLouvain Louvain School of Engineering, developed antennas for the 'LaRa' measuring instrument (Lander Radioscience ), which will go to Mars in 2020.

Prof. Craeye's laboratory has been producing antennas for more than 15 years, for various uses: road radars, magnetic resonance imaging, tracking objects equipped with radiofrequency identification (RFID) chips. The goal is always the same: retrieve remotely data sent by a measuring instrument (of a vehicle's speed, the body's internal functions, an object's or individual's location, etc.).
For this expertise, as part of the ExoMars mission, the European Space Agency (ESA) contacted (via Antwerp Space) UCLouvain. The mission's purpose is to study the rotation of Mars in order to learn more about the composition of its core and determine whether the planet was/will someday be habitable. How? By means of the LaRa instrument, which will communicate with Earth via radio waves. Thus the importance of antennas: they receive and emit radio waves. By measuring the Doppler effect—the difference between the frequencies of the waves emitted on the way (Earth-Mars) and those on the return (Mars-Earth)—the antennas will make it possible to better understand the movement of Mars and therefore the composition of its core. This is why LaRa is equipped with 100% UCLouvain-made antennas: a receiving antenna and two transmitting antennas (one of which is a backup).
[b]Production requirements:[/b]
  • Resilience: Earth's atmosphere protects us from the sun's rays and limits temperature variations between day and night, which makes our planet habitable. Mars doesn't have an atmosphere. Temperatures range from 80° C during the day (when the sun is most intense) to -125° C at night. Not to mention vibrations generated by dust storms.

  • Lightweight and miniaturised: the LaRa instrument will be equipped with multiple components, each for a specific use as part of the ExoMars research mission. Its total weight is distributed among its components, which must therefore be the smallest and lightest possible.
The UCLouvain team's greatest feat: from concept to prototype, it created the antenna in a mere three months.
The advantages of UCLouvain's design:
  • An innovative manufacturing process: antennas of unprecedented shape were created by milling from a single block of aluminium—no welding means increased resistance to vibration and temperature variations, in addition to being extremely lightweight. The receiving antennas weigh 132g maximum, the emitting antennas 162g maximum. And they fit in the palm of the hand. The design's originality won over the ESA.

  • Exceptional sensitivity: the antennas are capable of capturing a radio signal from any direction, and focus it on the transponder's electronics—an area of less than 1 cm² in the centre of the antenna—for the strongest possible signal.
What next? Applications are being developed in the field of satellite communications. And many industrial collaborations exist in fields beyond space and as varied as medical imaging, radio-frequency sensors, radar and telecommunications.

Explore further
Researcher makes the heart of Mars speak

Provided by Université catholique de Louvain
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Falcon Heavy to launch NASA Psyche asteroid mission
by Jeff Foust — February 28, 2020
[Image: falconheavy-arabsat6anew.jpg]NASA announced Feb. 28 it will use a Falcon Heavy to launch its Psyche asteroid mission in 2022. Credit: Craig Vander Galien

WASHINGTON — NASA awarded a contract to SpaceX Feb. 28 for the launch of a mission to a large metallic asteroid on the company’s Falcon Heavy rocket.
NASA said that it will use a Falcon Heavy to launch its Psyche mission in July 2022 from Launch Complex 39A at the Kennedy Space Center. The contract is valued at $117 million, which includes the launch itself and other mission-related costs.
Psyche is one of two missions NASA selected in January 2017 for its Discovery program of relatively low-cost planetary science missions. Psyche will use a Mars flyby in 2023 to arrive at its destination, an asteroid also called Psyche, in January 2026. The spacecraft will go into orbit around the asteroid, one of the largest in the main asteroid belt between Mars and Jupiter.

The asteroid is primarily made of iron and nickel, and could be the remnant of a core of a protoplanet that attempted to form there before high-speed collisions with other planetesimals broke it apart. Planetary scientists believe that studies of the asteroid Psyche could help them better understand the formation of the solar system.
The Psyche mission is led by Arizona State University, with Maxar the prime contractor for the spacecraft. The launch will also carry two smallsat secondary payloads: Escape and Plasma Acceleration and Dynamics Explorers (EscaPADE), which will study the Martian atmosphere, and Janus, which will study binary asteroids.
The other mission selected for the Discovery program in 2017, Lucy, will visit Trojan asteroids in the same orbit around the sun as Jupiter. NASA awarded a launch contract to United Launch Alliance in January 2019 for the launch of that mission on an Atlas 5 in October 2021.
SpaceX subsequently filed a protest with the Government Accountability Office over that award, arguing that it could have launched the mission for significantly less than the $148.3 million value of the ULA contract. ULA argued that it provided schedule assurance needed for a mission that must launch in a 20-day window. SpaceX dropped the protest in April 2019, nearly two months after it was filed.
Since them, though, SpaceX has enjoyed success winning NASA launch contracts. Within a week of dropping the GAO protest, SpaceX won a contract for the launch of the Double Asteroid Redirect Test (DART) spacecraft on a Falcon 9. That mission, launching in June 2021, will send a spacecraft to the near Earth asteroid Didymos, deliberately colliding with a small moon orbiting that asteroid to test deflection techniques for planetary defense.
In July 2019, NASA won a contract for the launch of NASA’s Imaging X-Ray Polarimetry Explorer (IXPE) astrophysics mission, scheduled for launch on a Falcon 9 in April 2021. That spacecraft was baselined for launch on a much smaller Pegasus rocket from Northrop Grumman, but SpaceX won the contract at a price lower than previous Pegasus missions.
NASA awarded SpaceX a contract Feb. 4 for the launch of its Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Earth science mission on a Falcon 9 in December 2022. NASA awarded that contract despite, less than a week later, stating in its fiscal year 2021 budget proposal it would seek to cancel the mission. PACE had been proposed for cancellation in the previous three years’ budget requests, and each time Congress rejected the cancellation and funded the mission.
Psyche is NASA’s first mission to use SpaceX’s Falcon Heavy rocket as the primary customer, although some NASA payloads flew on the Falcon Heavy STP-2 mission for the Defense Department’s Space Test Program in June 2019. SpaceX’s current manifest for the heavy-lift rocket includes two classified missions for the U.S. Air Force in late 2020 and early 2021 and a ViaSat-3 broadband communications satellite for Viasat in mid-2021.
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Exhaustive seismic data from repeating earthquakes and new data-processing methods have yielded the best evidence yet that the Earth's inner core is rotating—revealing a better understanding of the hotly debated processes that control the planet's magnetic field.

MAY 12, 2020
Growing mountains or shifting ground: What is going on in Earth's inner core?
[Image: growingmount.jpg]A new study of Earth's inner core used seismic data from repeating earthquakes, called doublets, to find that refracted waves, blue, rather than reflected waves, purple, change over time -- providing the best evidence yet that Earth's inner core is rotating. Credit: Michael Vincent
Exhaustive seismic data from repeating earthquakes and new data-processing methods have yielded the best evidence yet that the Earth's inner core is rotating—revealing a better understanding of the hotly debated processes that control the planet's magnetic field.

The new study by researchers from the University of Illinois at Urbana-Champaign is published in the journal Earth and Planetary Science Letters.
Geologists do not fully understand how the Earth's magnetic field generator works, but suspect it is closely linked to dynamic processes near the inner core-outer core boundary area, the researchers said. Shifts in the location of the magnetic poles, changes in field strength and anomalous seismic data have prompted researchers to take a closer look.
"In 1996, a small but systematic change of seismic waves passing through the inner core was first detected by our group, which we interpreted as evidence for differential rotation of the inner core relative to the Earth's surface," said geology professor and study co-author Xiaodong Song, who is now at Peking University. "However, some studies believe that what we interpret as movement is instead the result of seismic waves reflecting off an alternately enlarging and shrinking inner core boundary, like growing mountains and cutting canyons."

[Image: 1-growingmount.jpg]
Geology professor Xiaodong Song. Credit: L. Brian Stauffer
The researchers present seismic data from a range of geographic locations and repeating earthquakes, called doublets, that occur in the same spot over time. "Having data from the same location but different times allows us to differentiate between seismic signals that change due to localized variation in relief from those that change due to movement and rotation," said Yi Yang, a graduate student and lead author of the study.
The team found that some of the earthquake-generated seismic waves penetrate through the iron body below the inner core boundary and change over time, which would not happen if the inner core were stationary, the researchers said. "Importantly, we are seeing that these refracted waves change before the reflected waves bounce off the inner core boundary, implying that the changes are coming from inside the inner core," Song said.
The basis of the debate lies in the fact the prior studies looked at a relatively small pool of somewhat ambiguous data generated from a method that is highly dependent on accurate clock time, the researchers said.
"What makes our analysis different is our precise method for determining exactly when the changes in seismic signals occur and arrive at the various seismic stations across the globe," Yang said. "We use a seismic wave that did not reach inner core as a reference wave in our calculations, which eliminates a lot of the ambiguity."
This precise arrival time analysis, an extensive collection of the best quality data and careful statistical analysis performed by Yang, are what give this study its power, Song said. "This work confirms that the temporal changes come mostly, if not all, from the body of the inner core, and the idea that inner core surface changes are the sole source of the signal changes can now be ruled out," he said.

Explore further
Reproducing core conditions suggests Earth's outer core less dense than liquid iron

[b]More information:[/b] Yi Yang et al, Origin of temporal changes of inner-core seismic waves, Earth and Planetary Science Letters (2020). DOI: 10.1016/j.epsl.2020.116267
[b]Journal information:[/b] Earth and Planetary Science Letters [/url]

Provided by [url=]University of Illinois at Urbana-Champaign


Sang Real.
[Image: sanne-cottaar-earth-globe-spinning-blobs-llsvp.gif]
Song said. "This work confirms that the temporal changes come mostly, if not all, from the body of the inner core, and the idea that inner core surface changes are the sole source of the signal changes can now be ruled out,"
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
MAY 20, 2020
Swarm probes weakening of Earth's magnetic field
[Image: swarmprobesw.jpg]The magnetic field is thought to be largely generated by an ocean of superheated, swirling liquid iron that makes up Earth’s the outer core 3000 km under our feet. Acting like the spinning conductor in a bicycle dynamo, it generates electrical currents and thus the continuously changing electromagnetic field. Other sources of magnetism come from minerals in Earth’s mantle and crust, while the ionosphere, magnetosphere and oceans also play a role. ESA’s constellation of three Swarm satellites is designed to identify and measure precisely these different magnetic signals. This will lead to new insight into many natural processes, from those occurring deep inside the planet, to weather in space caused by solar activity. Credit: ESA/ATG Medialab
In an area stretching from Africa to South America, Earth's magnetic field is gradually weakening. This strange behaviour has geophysicists puzzled and is causing technical disturbances in satellites orbiting Earth. Scientists are using data from ESA's Swarm constellation to improve our understanding of this area known as the 'South Atlantic Anomaly.'

Earth's magnetic field is vital to life on our planet. It is a complex and dynamic force that protects us from cosmic radiation and charged particles from the Sun. The magnetic field is largely generated by an ocean of superheated, swirling liquid iron that makes up the outer core around 3000 km beneath our feet. Acting as a spinning conductor in a bicycle dynamo, it creates electrical currents, which in turn, generate our continuously changing electromagnetic field.
This field is far from static and varies both in strength and direction. For example, recent studies have shown that the position of the north magnetic pole is changing rapidly.
Over the last 200 years, the magnetic field has lost around 9% of its strength on a global average. A large region of reduced magnetic intensity has developed between Africa and South America and is known as the South Atlantic Anomaly.
From 1970 to 2020, the minimum field strength in this area has dropped from around 24 000 nanoteslas to 22 000, while at the same time the area of the anomaly has grown and moved westward at a pace of around 20 km per year. Over the past five years, a second centre of minimum intensity has emerged southwest of Africa—indicating that the South Atlantic Anomaly could split up into two separate cells.
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The South Atlantic Anomaly refers to an area where our protective shield is weak. This animation shows the magnetic field strength at Earth’s surface from 2014-2020 based on data collected by the Swarm satellite constellation. Credit: Division of Geomagnetism, DTU Space
Earth's magnetic field is often visualised as a powerful dipolar bar magnet at the centre of the planet, tilted at around 11° to the axis of rotation. However, the growth of the South Atlantic Anomaly indicates that the processes involved in generating the field are far more complex. Simple dipolar models are unable to account for the recent development of the second minimum.
Scientists from the Swarm Data, Innovation and Science Cluster (DISC) are using data from ESA's Swarm satellite constellation to better understand this anomaly. Swarm satellites are designed to identify and precisely measure the different magnetic signals that make up Earth's magnetic field.

Jürgen Matzka, from the German Research Centre for Geosciences, says, "The new, eastern minimum of the South Atlantic Anomaly has appeared over the last decade and in recent years is developing vigorously. We are very lucky to have the Swarm satellites in orbit to investigate the development of the South Atlantic Anomaly. The challenge now is to understand the processes in Earth's core driving these changes."
It has been speculated whether the current weakening of the field is a sign that Earth is heading for an eminent pole reversal—in which the north and south magnetic poles switch places. Such events have occurred many times throughout the planet's history and even though we are long overdue by the average rate at which these reversals take place (roughly every 250 000 years), the intensity dip in the South Atlantic occurring now is well within what is considered normal levels of fluctuations.
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The South Atlantic Anomaly refers to an area where our protective shield is weak. White dots on the map indicate individual events when Swarm instruments registered the impact of radiation from April 2014 to August 2019. The background is the magnetic field strength at the satellite altitude of 450 km. Credit: Division of Geomagnetism, DTU Space
At surface level, the South Atlantic Anomaly presents no cause for alarm. However, satellites and other spacecraft flying through the area are more likely to experience technical malfunctions as the magnetic field is weaker in this region, so charged particles can penetrate the altitudes of low-Earth orbit satellites.
The mystery of the origin of the South Atlantic Anomaly has yet to be solved. However, one thing is certain: magnetic field observations from Swarm are providing exciting new insights into the scarcely understood processes of Earth's interior.

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Video: Magnetic field update

Provided by European Space Agency
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With a forked tongue the snake singsss...
AUGUST 11, 2020
Main Belt asteroid Psyche might be the remnant of a planet that never fully formed
by Nancy Ambrosiano, Los Alamos National Laboratory
[Image: mainbeltaste.jpg]Artist's conception of asteroid Psyche, whose composition has been proposed as a porous metallic body hurtling through space, thanks to computer modeling of its largest crater. Credit: Peter Rubin and Arizona State University
New 2-D and 3-D computer modeling of impacts on the asteroid Psyche, the largest Main Belt asteroid, indicate it is probably metallic and porous in composition, something like a flying cosmic rubble pile. Knowing this will be critical to NASA's forthcoming asteroid mission, Psyche: Journey to a Metal World, that launches in 2022.

"This mission will be the first to visit a metallic asteroid, and the more we, the scientific community, know about Psyche prior to launch, the more likely the mission will have the most appropriate tools for examining Psyche and collecting data," said Wendy K. Caldwell, Los Alamos National Laboratory Chick Keller Postdoctoral Fellow and lead author on a paper published recently in the journal Icarus. "Psyche is an interesting body to study because it is likely the remnant of a planetary core that was disrupted during the accretion stage, and we can learn a lot about planetary formation from Psyche if it is indeed primarily metallic."
Modeling impact structures on Psyche contributes to our understanding of metallic bodies and how cratering processes on large metal objects differ from those on rocky and icy bodies, she noted.
The team provides the first 3-D models of the formation of Psyche's largest impact crater, and it is the first work to use impact crater models to inform asteroid composition. The 2-D and 3-D models indicate an oblique impact angle where an incoming object would have struck the asteroid's surface, deforming Psyche in a very specific and predictable manner, given the likely materials involved.
Metals deform differently from other common asteroid materials, such as silicates, and impacts into targets of similar composition to Psyche should result in craters similar to those observed on Psyche.

Simulating an impact crater on an asteroid. Credit: Los Alamos National Laboratory
An animation video using the team's simulation output shows a theoretical impact scenario that could have led to Psyche's largest crater. The simulation shows how some material is ejected into space after impact and reveals the crater modification stage, where the impact area shows the resulting damaged material.
"Our ability to model the impact through the modification stage is essential to understanding how craters form on metallic bodies," Caldwell said. "In early stages of crater formation, the target material behaves like a fluid. In the modification stage, however, the strength of the target material plays a key role in how material that isn't ejected 'settles' into the crater."

The researchers' results corroborate estimates on Psyche's compositions based on observational measuring techniques. Of particular interest is the material that provided the best match, Monel. Monel is an alloy based on ore from Sudbury Crater, an impact structure in Canada. The ore is thought to have come from the impactor that formed the crater, meaning the ore itself is likely to have extraterrestrial origins. The modeling successes using Monel demonstrate that Psyche's material composition behaves similarly under shock conditions to extraterrestrial metals.
The modeling tool used in the work, run on a Los Alamos supercomputer, was the FLAG hydrocode, previously shown to be effective in modeling impact craters and an ideal choice to model crater formation on Psyche. Based upon the probable impact velocity, local gravity, and bulk density estimates, the formation of Psyche's largest crater likely was dominated by strength rather than gravity, Caldwell said.
"It's incredible what we can accomplish with the laboratory's resources," Caldwell noted. "Our supercomputers are some of the most powerful in the world, and for large problems like asteroid impacts, we really rely on our numerical modeling tools to supplement observational data."

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Rare metallic asteroids might have erupted molten iron

[b]More information:[/b] Wendy K. Caldwell et al. Understanding Asteroid 16 Psyche's composition through 3D impact crater modeling, Icarus (2020). DOI: 10.1016/j.icarus.2020.113962
[b]Journal information:[/b] Icarus [/url]

Provided by [url=]Los Alamos National Laboratory
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With a forked tongue the snake singsss...
From the last post

Quote:The researchers' results corroborate estimates on Psyche's compositions,
based on observational measuring techniques.
Of particular interest,
is the material that provided the best match, Monel.

Monel is an alloy based on ore from Sudbury Crater,
an impact structure in Canada.
The ore is thought to have come from the impactor that formed the crater,
meaning the ore itself is likely to have extraterrestrial origins.

The modeling successes using Monel,
demonstrate that Psyche's material composition,
behaves similarly under shock conditions to extraterrestrial metals.

The modeling tool used in the work,
run on a Los Alamos supercomputer, was the FLAG hydrocode  Naughty
previously shown to be effective in modeling impact craters,
and an ideal choice to model crater formation on Psyche.

The wikipedia article on Monel is excellent

Quote:Stronger than pure nickel, 
Monel alloys are resistant to corrosion by many agents, 
including rapidly flowing seawater. <---
They can be fabricated readily by hot- and cold-working, machining, and welding

It is an expensive alloy, 
hence its use is limited to those applications where it cannot be replaced with cheaper alternatives.
Compared to carbon steel, piping in Monel is more than 3 times as expensive.

It is resistant to corrosion and acids,
 and some alloys can withstand a fire in pure oxygen. 

It is commonly used in applications with highly corrosive conditions. Whip
Small additions of aluminium and titanium form an alloy (K-500) 
with the same corrosion resistance,
but with much greater strength due to gamma prime formation on aging. 
Monel is typically much more expensive than stainless steel.
OCTOBER 26, 2020
Study offers more complete view of massive asteroid Psyche
[Image: swristudyoff.jpg]The massive asteroid 16 Psyche is the subject of a new study by SwRI scientist Tracy Becker, who observed the object at ultraviolet wavelengths. Credit: Maxar/ASU/P. Rubin/NASA/JPL-Caltech
A new study authored by Southwest Research Institute planetary scientist Dr. Tracy Becker discusses several new views of the asteroid 16 Psyche, including the first ultraviolet observations. The study, which was published today in The Planetary Science Journal and presented at the virtual meeting of the American Astronomical Society's Division for Planetary Sciences, paints a clearer view of the asteroid than was previously available.

At about 140 miles in diameter, Psyche is one of the most massive objects in the main asteroid belt orbiting between Mars and Jupiter. Previous observations indicate that Psyche is a dense, largely metallic object thought to be the leftover core of a planet that failed in formation.
"We've seen meteorites that are mostly metal, but Psyche could be unique in that it might be an asteroid that is totally made of iron and nickel," Becker said. "Earth has a metal core, a mantle and crust. It's possible that as a Psyche protoplanet was forming, it was struck by another object in our solar system and lost its mantle and crust."
Becker observed the asteroid at two specific points in its rotation to view both sides of Psyche completely and delineate as much as possible from observing the surface at ul-traviolet (UV) wavelengths.
"We were able to identify for the first time on any asteroid what we think are iron oxide ultraviolet absorption bands," she said. "This is an indication that oxidation is happen-ing on the asteroid, which could be a result of the solar wind hitting the surface."
Becker's study comes as NASA is preparing to launch the spacecraft Psyche, which will travel to the asteroid as part of an effort to understand the origin of planetary cores. The mission is set to launch in 2022. Metal asteroids are relatively rare in the solar system, and scientists believe Psyche could offer a unique opportunity to see inside a planet.
"What makes Psyche and the other asteroids so interesting is that they're considered to be the building blocks of the solar system," Becker said. "To understand what really makes up a planet and to potentially see the inside of a planet is fascinating. Once we get to Psyche, we're really going to understand if that's the case, even if it doesn't turn out as we expect. Any time there's a surprise, it's always exciting."
Becker also observed that the asteroid's surface could be mostly iron, but she noted that the presence of even a small amount of iron could dominate UV observations. Howev-er, while observing Psyche, the asteroid appeared increasingly reflective at deeper UV wavelengths.
"This is something that we need to study further," she said. "This could be indicative of it being exposed in space for so long. This type of UV brightening is often attributed to space weathering."

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Pure metal asteroid has mysterious water deposits

[b]More information:[/b] Tracy M. Becker et al, HST UV Observations of Asteroid (16) Psyche, The Planetary Science Journal (2020). DOI: 10.3847/PSJ/abb67e
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
A good reason to study this object.
This is the same story...from a different pov...
durasteel hulls for EVERYONE!

On a satellite I ride. Nothing down below can hide.
Cry  Arrow

JUNE 9, 2021
Asteroid 16 Psyche might not be what scientists expected
by Mikayla MacE Kelley, University of Arizona
[Image: asteroid-16-psyche-mig.jpg]An artist’s concept of asteroid 16 Psyche. Credit: Maxar/ASU/P.Rubin/NASA/JPL-Caltech
The widely studied metallic asteroid known as 16 Psyche was long thought to be the exposed iron core of a small planet that failed to form during the earliest days of the solar system. But new University of Arizona-led research suggests that the asteroid might not be as metallic or dense as once thought, and hints at a much different origin story.
Scientists are interested in 16 Psyche because if its presumed origins are true, it would provide an opportunity to study an exposed planetary core up close. NASA is scheduled to launch its Psyche mission in 2022 and arrive at the asteroid in 2026.
UArizona undergraduate student David Cantillo is lead author of a new paper published in The Planetary Science Journal that proposes 16 Psyche is 82.5% metal, 7% low-iron pyroxene and 10.5% carbonaceous chondrite that was likely delivered by impacts from other asteroids. Cantillo and his collaborators estimate that 16 Psyche's bulk density—also known as porosity, which refers to how much empty space is found within its body—is around 35%.
These estimates differ from past analyses of 16 Psyche's composition that led researchers to estimate it could contain as much as 95% metal and be much denser.
"That drop in metallic content and bulk density is interesting because it shows that 16 Psyche is more modified than previously thought," Cantillo said.
Rather than being an intact exposed core of an early planet, it might actually be closer to a rubble pile, similar to another thoroughly studied asteroid—Bennu. UArizona leads the science mission team for NASA's OSIRIS-REx mission, which retrieved a sample from Bennu's surface that is now making its way back to Earth.
"Psyche as a rubble pile would be very unexpected, but our data continues to show low-density estimates despite its high metallic content," Cantillo said.
Asteroid 16 Psyche is about the size of Massachusetts, and scientists estimate it contains about 1% of all asteroid belt material. First spotted by an Italian astronomer in 1852, it was the 16th asteroid ever discovered.
"Having a lower metallic content than once thought means that the asteroid could have been exposed to collisions with asteroids containing the more common carbonaceous chondrites, which deposited a surface layer that we are observing," Cantillo said. This was also observed on asteroid Vesta by the NASA Dawn spacecraft.
Asteroid 16 Psyche has been estimated to be worth $10,000 quadrillion (that's $10,000 followed by 15 more zeroes), but the new findings could slightly devalue the iron-rich asteroid.
"This is the first paper to set some specific constraints on its surface content. Earlier estimates were a good start, but this refines those numbers a bit more," Cantillo said.
The other well-studied asteroid, Bennu, contains a lot of carbonaceous chondrite material and has porosity of over 50%, which is a classic characteristic of a rubble pile.
Such high porosity is common for relatively small and low-mass objects such as Bennu—which is only as large as the Empire State Building—because a weak gravitational field prevents the object's rocks and boulders from being packed together too tightly. But for an object the size of 16 Psyche to be so porous is unexpected.
"The opportunity to study an exposed core of a planetesimal is extremely rare, which is why they're sending the spacecraft mission there," Cantillo said, "but our work shows that 16 Psyche is a lot more interesting than expected."  LilD
Past estimates of 16 Psyche's composition were done by analyzing the sunlight reflected off its surface. The pattern of light matched that of other metallic objects. Cantillo and his collaborators instead recreated 16 Psyche's regolith—or loose rocky surface material—by mixing different materials in a lab and analyzing light patterns until they matched telescope observations of the asteroid. There are only a few labs in the world practicing this technique, including the UArizona Lunar and Planetary Laboratory and the Johns Hopkins Applied Physics Laboratory in Maryland, where Cantillo worked while in high school.
"I've always been interested in space," said Cantillo, who is also president of the UArizona Astronomy Club. "I knew that astronomy studies would be heavy on computers and observation, but I like to do more hands-on kind of work, so I wanted to connect my studies to geology somehow. I'm majoring geology and minoring in planetary science and math."
"David's paper is an example of the cutting-edge research work done by our undergraduate students," said study co-author Vishnu Reddy, an associate professor of planetary sciences who heads up the lab in which Cantillo works. "It is also a fine example of the collaborative effort between undergraduates, graduate students, postdoctoral fellows and staff in my lab."
The researchers also believe the carbonaceous material on 16 Psyche's surface is rich in water, so they will next work to merge data from ground-based telescopes and spacecraft missions to other asteroids to help determine the amount of water present.

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Study offers more complete view of massive asteroid Psyche

[b]More information:[/b] David C. Cantillo et al, Constraining the Regolith Composition of Asteroid (16) Psyche via Laboratory Visible Near-infrared Spectroscopy, The Planetary Science Journal (2021). DOI: 10.3847/PSJ/abf63b
[b]Journal information:[/b] The Planetary Science Journal
Along the vines of the Vineyard.
With a forked tongue the snake singsss...

Still no explanation as to why there is so much metal though.
This asteroid is the size of Massachusetts,
and maybe there is a high metal content central core fragment in the rubble pile,
that originates from a planetary core.
It could be half the size of Massachusets,
and the rest an accumulated rubble pile of impact debris,
of carbonaceous chondrite meteors,
and metallic ejecta from the impact on the core.

Quote:Psyche as a rubble pile Bricks 
would be very unexpected, 
but our data continues to show low-density estimates,
despite its high metallic content,

"thought to be the leftover core of a planet that failed in formation. used to occupy that orbit."
On a satellite I ride. Nothing down below can hide.
An Unexpected Planetary Feature Has Just Been Found on Venus
Michelle Starr  6 hrs ago

[font="Segoe UI", "Segoe WP", Arial, sans-serif]Venus may be a toxic hell-planet, but new evidence suggests it might have more in common than Earth than we realized.[/font]

[font="Segoe UI", "Segoe WP", Arial, sans-serif][Image: AALjXsC.img?h=324&w=799&m=6&q=60&o=f&l=f][/font]

[font="Segoe UI", "Segoe WP", Arial, sans-serif][font="Segoe UI", "Segoe WP", Arial, sans-serif]© Paul Byrne; NASA/JPL[/font][/font]
Scientists have just found evidence that Venus' crust could have tectonic blocks that rub together, not dissimilar to broken blocks of pack ice. It's not entirely like Earth's plate tectonics, but the discovery does suggest that the planet's crust isn't one globally continuous lithosphere, and that convective motion swirls below.

This doesn't just offer insights into Venus - it could help us better understand the evolution and dynamics of tectonics on early Earth.

"We've identified a previously unrecognized pattern of tectonic deformation on Venus, one that is driven by interior motion just like on Earth," said planetary scientist Paul Byrne of North Carolina State University.

"Although different from the tectonics we currently see on Earth, it is still evidence of interior motion being expressed at the planet's surface."

Earth really is a unique little oddball in the Solar System, in many ways. One of those ways is its system of plate tectonics - shifting scales of crust that grind against each other and overlap (subduct), moving over a hot, molten interior planetary layer.

We don't see this kind of activity on Mercury, or Mars, or the Moon. And nor do we see it on Venus - which is strange, considering the similar sizes and geological compositions of Venus and Earth.

The two planets took quite different evolutionary paths, in spite of their similarities, and the reasons for that are not very well understood. If we can work out how and why Earth and Venus turned, respectively, into a lush, thriving ocean world and a scorching wasteland, we will have a better handle on similar exoplanets, out there in the wider galaxy.

Byrne and his team were mapping the surface of Venus, using radar images taken by NASA's Magellan probe in the 1990s. They noticed that, in the lowlands, some features seem to suggest large-scale movement - shear stresses and deformations from the motions and interactions of large blocks of crust.

To figure out if what they were seeing was what they thought they were seeing, the team performed modeling. They found that convective flow beneath the crust of Venus could produce the observed features, if the crust was broken up into large chunks, rather than plates.

"Plate tectonics on Earth are driven by convection in the mantle. The mantle is hot or cold in different places, it moves, and some of that motion transfers to Earth's surface in the form of plate movement," Byrne explained.

"A variation on that theme seems to be playing out on Venus as well. It's not plate tectonics like on Earth - there aren't huge mountain ranges being created here, or giant subduction systems - but it is evidence of deformation due to interior mantle flow, which hasn't been demonstrated on a global scale before."

Recent evidence also suggests that Venus may still be volcanically active. A study released last year found that volcanic features on the planet's surface are relatively recent. We also know that most of the planet has been volcanically resurfaced in the last billion years or so.

In order to produce the features Byrne's team observed, the tectonic hijinks must have taken place after the resurfacing. This suggests that, not only is this activity relatively recent, it may still be ongoing.

This suggests an intermediate stage of tectonic activity, on a continuum between the fixed global shells of Mercury, Mars, and the Moon, and the mobility of Earth's flimsier tectonic plates. This could help us better understand exoplanets in the 'Venus zone' of orbit around their host stars, and the interiors of rocky planets.

It also might offer some insight into the tectonic processes on early Earth.

"The thickness of a planet's lithosphere depends mainly upon how hot it is, both in the interior and on the surface," Byrne said.

"Heat flow from the young Earth's interior was up to three times greater than it is now, so its lithosphere may have been similar to what we see on Venus today: not thick enough to form plates that subduct, but thick enough to have fragmented into blocks that pushed, pulled, and jostled."

Future observations by upcoming Venus missions by NASA and the European Space Agency will tell us more about this fascinating discovery.

[font="Segoe UI", "Segoe WP", Arial, sans-serif][font="Segoe UI", "Segoe WP", Arial, sans-serif]The research has been published in PNAS.

Source: An Unexpected Planetary Feature Has Just Been Found on Venus ([/font]

Bob... Ninja Assimilated Angel
"The Morning Light, No sensation to compare to this, suspended animation, state of bliss, I keep my eyes on the circling sky, tongue tied and twisted just and Earth Bound Martian I" Learning to Fly Pink Floyd [Video:]

If you copy and paste your link's text -- into notepad --
the copy and paste that 
into your forum post,
then we can read the thing .... without all the ridiculous font nonsense.

Or just post the link and title
so people don't have to read through the font nonsense.

Thank You Vic I will do so in future.

This does NOT occur when I use FireFox, it is Microsoft Edge which does this.


Won't happen again.

Bob... Ninja Assimilated Angel
"The Morning Light, No sensation to compare to this, suspended animation, state of bliss, I keep my eyes on the circling sky, tongue tied and twisted just and Earth Bound Martian I" Learning to Fly Pink Floyd [Video:]
Arrow #80
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NASA’s InSight Lander Provides New Information about Crust, Mantle and Core of Mars

Jul 26, 2021 by News Staff / Source

According to new analyses of data from the Seismic Experiment for Interior Structure (SEIS) instrument deployed during NASA’s InSight mission, Mars likely has a 24- to 72-km- (15-45-mile) thick crust with a very deep lithosphere close to 500 km (311 miles); similar to the Earth, a low-velocity layer probably exists beneath the Martian lithosphere; the crust of Mars is likely highly enriched in radioactive elements that help to heat this layer at the expense of the interior; the Martian core is liquid and large, 1,830 km (1,137 miles), which means that the mantle has only one rocky layer rather than two like the Earth has. These results appear in three papers in the journal Science.
[Image: image_9897_1e-Mars-Core.jpg]
Schematic view of the propagation of seismic waves in the Martian crust and seismic conversions at the base of the discontinuity, at a depth of 10 km (6.2 miles). Image credit: IPGP.

Like Earth, Mars heated up as it formed from the dust and larger clumps of meteoritic material orbiting the Sun that helped to shape our early Solar System.
Over the first tens of millions of years, the planet separated into three distinct layers — the crust, mantle, and core — in a process called differentiation.
Part of InSight’s mission was to measure the depth, size, and structure of these three layers.
“When we first started putting together the concept of the mission more than a decade ago, the information in these papers is what we hoped to get at the end,” said InSight’s principal investigator Dr. Bruce Banerdt, a researcher at NASA’s Jet Propulsion Laboratory.
“This represents the culmination of all the work and worry over the past decade.”
The earthquakes most people feel come from faults caused by tectonic plates shifting.
Unlike Earth, Mars has no tectonic plates; its crust is instead like one giant plate. But faults, or rock fractures, still form in the Martian crust due to stresses caused by the slight shrinking of the planet as it continues to cool.
The members of the InSight team spend much of their time searching for bursts of vibration in seismograms, where the tiniest wiggle on a line can represent a quake or, for that matter, noise created by wind.
If seismogram wiggles follow certain known patterns (and if the wind is not gusting at the same time), there’s a chance they could be a quake.
The initial wiggles are primary, or P, waves, which are followed by secondary, or S, waves. These waves can also show up again later in the seismogram after reflecting off layers inside the planet.
“What we’re looking for is an echo,” said Dr. Amir Khan, a researcher at ETH Zurich.
“We’re detecting a direct sound — the quake — and then listening for an echo off a reflector deep underground.”
“Layering within the crust is something we see all the time on Earth,” said Dr. Brigitte Knapmeyer-Endrun, a researcher at the University of Cologne.
“A seismogram’s wiggles can reveal properties like a change in porosity or a more fractured layer.”
[Image: image_9897_2e-Mars-Core.jpg]
An artist’s impression of the internal structure of Mars. Image credit: David Ducros / IPGP.

The InSight scientists found the Martian crust was thinner than expected and may have two or even three sub-layers.
It goes as deep as 20 km (12.4 miles) if there are two sub-layers, or 37 km (23 miles) if there are three.
Beneath that is the mantle, which extends 1,560 km (969 miles) below the surface.
At the heart of Mars is the core, which has a radius of 1,830 km. Confirming the size of the molten core was especially exciting for the authors.
“This study is a once-in-a-lifetime chance,” said Dr. Simon Stähler, a researcher at the ETH Zurich.
“It took scientists hundreds of years to measure Earth’s core; after the Apollo missions, it took them 40 years to measure the Moon’s core. InSight took just two years to measure Mars’ core.”
[font=Lora, serif]
[font=Lora, serif]Amir Khan [i]et al[/i]. 2021. Upper mantle structure of Mars from InSight seismic data. [i]Science[/i] 373 (6553): 434-438; doi: 10.1126/science.abf2966

Brigitte Knapmeyer-Endrun [i]et al[/i]. 2021. Thickness and structure of the Martian crust from InSight seismic data. [i]Science[/i] 373 (6553): 438-443; doi: 10.1126/science.abf8966
Simon C. Stähler [i]et al[/i]. 2021. Seismic detection of the Martian core. [i]Science[/i] 373 (6553): 443-448; doi: 10.1126/science.abi7730[/font]
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With a forked tongue the snake singsss...
Observatory in Chile Takes Highest-Resolution Measurements
of Asteroid Surface Temperatures Ever Obtained from Earth

Atacama Large Millimeter/submillimeter Array (ALMA) in Chile,
The array of 66 radio telescopes
enabled the team to map the thermal emissions 
from Psyche's entire surface
at a resolution of 30 km
(where each pixel is 30 km by 30 km) Lol 
and generate an image of the asteroid composed of about 50 pixels.

[Image: Katherine_deKleer-Asteroid-450px-Width.max-500x500.gif]

"We've known for many years that objects in this class are not,
in fact, solid metal,
but what they are and how they formed is still an enigma,"
de Kleer says.
The findings reinforce alternative proposals for Psyche's surface composition,
 including that Psyche could be a primitive asteroid,
that formed closer to the sun than it is today Nonono 
of a core of a fragmented protoplanet. 

Because surface emission is affected by the presence of metal on the surface,
their finding indicates that Psyche's surface,
is no less than 30 percent metal.

A smooth solid surface emits well-organized polarized light; 
the light emitted by Psyche, however, was scattered, 
suggesting that rocks on the surface are peppered with metallic grains.


Phil Iconoclasti-Christ Plait ---> Kickbut <--- V
an in depth PDF on Psyche.
Phil is promoting ferro Sheep volcanoes on Psyche from the new pdf.

This is the interesting pdf that Phil refers to on Psyche:
Asteroid 16 Psyche: Shape, Features, and Global Map

This is Phil's link with some of his content.

A new hypothesis is that the craters depicted here
may actually be ferrovolcanoes 
volcanoes that erupted molten metals.

[Image: artwork_psyche_asteroid_2021-1.jpg]

Overall, Psyche is shaped like a flat potato,
measuring 278 × 238 × 171 km in size (± roughly 5 km),
consistent with though more accurate than previous measurements made in the past,
and it spins once every 4.2 hours.

But there are other ideas, too.

One is that it had multiple impacts  Gangup
that shattered it into smaller chunks that reaccumulated. Nonono

That would mean it’s porous,
like a box of rocks and metal chunks instead of one solid body.
We see smaller asteroids like that,
but Psyche is 100 times larger than those,
and it’s not clear that anything that big can be that porous.

The paper authors have another idea:
Psyche is still a differentiated world,
with a metal core and rocky crust ...
but it’s ferrovolcanic.

Ferrovolcanoes are eruptions of molten iron,
which is one of the coolest things ever.
Their idea is that the core stayed molten
while the surface cooled into a rocky crust,
but the molten metal would have erupted out where the crust was thinner.

[Image: psyche_asteroid_map-1.png]


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