The debate of whether the moon’s inner core is solid or molten has finally been settled by a team of scientists at the French National Centre for Scientific Research. According to the article published in the journal Nature in May last year, the inner heart of the moon is a solid ball and has an iron-like density.

"Our results," the team led by astronomer Arthur Briaud wrote, "question the evolution of the Moon magnetic field thanks to its demonstration of the existence of the inner core and support a global mantle overturn scenario that brings substantial insights on the timeline of the lunar bombardment in the first billion years of the Solar System."

Seismic information can be used to investigate the interior composition of celestial objects in the solar system. Scientists created a detailed chart of the moon's interior by understanding how acoustic waves created by quakes pass through and reflect from the material inside.

Also read |&nbsp;<a href="https://www.wionews.com/trending/universe-just-recorded-its-most-powerful-sonic-booms-in-stephans-quintet-778628">Universe just recorded its most powerful sonic booms in Stephan’s Quintet</a>

Although the Apollo mission has provided seismic data from the moon, its low resolution makes it hard to make accurate deductions. While it is known that the outer core comprises a fluid, however, what lies beneath it remained a debate for a long time as the models of both a solid and liquid core work well with the data from Apollo.

Briaud and his team members collected data from various space missions and laser-ranging experiments on the moon to determine lunar characteristics and compared the data to various types of cores to find out which was the closest match.

The lunar models suggested that denser material remains towards the centre, while less dense material rises above. This also explains the elements found near the volcanic regions on the moon.

It was found that the moon’s core has a fluid outer layer and a solid inner core, which is similar to Earth's. The model revealed that the outer core radius is about 362 kilometres (225 miles), and the inner core radius of around 258 kilometres (160 miles), making up 15 per cent of the entire radius of the moon.

Also read |&nbsp;<a href="https://www.wionews.com/trending/artemis-astronauts-will-shift-from-orion-to-starship-in-space-to-reach-moons-surface-778617">Artemis astronauts will shift from Orion to Starship in space to reach Moon's surface</a>

The team was also able to determine the density of the moon to be about 7,822 kilograms per cubic meter, which is similar to the density of iron.

Interestingly, in 2011 a team led by NASA Marshall planetary scientist Renee Weber came to similar results from their investigation, which Briaud says are confirmed by his team’s findings that the lunar core is similar to Earth’s core.

Understanding the lunar core’s composition will help in understanding how and why the moon’s magnetic field began declining about 3.2 billion years ago, which used to be powerful in its initial stages, as this usually happens due to motion and convection inside the core.

(With inputs from agencies)

The debate of whether the moon’s inner core is solid or molten has finally been settled by a team of scientists at the French National Centre for Scientific Research.

The debate of whether the moon’s inner core is solid or molten has finally been settled by a team of scientists at the French National Centre for Scientific Research. According to the article published in the journal Nature in May last year, the inner heart of the moon is a solid ball and has an iron-like density. "Our results," the team led by astronomer Arthur Briaud wrote, "question the evolution of the Moon magnetic field thanks to its demonstration of the existence of the inner core and support a global mantle overturn scenario that brings substantial insights on the timeline of the lunar bombardment in the first billion years of the Solar System." Seismic information can be used to investigate the interior composition of celestial objects in the solar system. Scientists created a detailed chart of the moon's interior by understanding how acoustic waves created by quakes pass through and reflect from the material inside. Also read | Universe just recorded its most powerful sonic booms in Stephan’s Quintet Although the Apollo mission has provided seismic data from the moon, its low resolution makes it hard to make accurate deductions. While it is known that the outer core comprises a fluid, however, what lies beneath it remained a debate for a long time as the models of both a solid and liquid core work well with the data from Apollo. Briaud and his team members collected data from various space missions and laser-ranging experiments on the moon to determine lunar characteristics and compared the data to various types of cores to find out which was the closest match. The lunar models suggested that denser material remains towards the centre, while less dense material rises above. This also explains the elements found near the volcanic regions on the moon. It was found that the moon’s core has a fluid outer layer and a solid inner core, which is similar to Earth's. The model revealed that the outer core radius is about 362 kilometres (225 miles), and the inner core radius of around 258 kilometres (160 miles), making up 15 per cent of the entire radius of the moon. Also read | Artemis astronauts will shift from Orion to Starship in space to reach Moon's surface The team was also able to determine the density of the moon to be about 7,822 kilograms per cubic meter, which is similar to the density of iron. Interestingly, in 2011 a team led by NASA Marshall planetary scientist Renee Weber came to similar results from their investigation, which Briaud says are confirmed by his team’s findings that the lunar core is similar to Earth’s core. Understanding the lunar core’s composition will help in understanding how and why the moon’s magnetic field began declining about 3.2 billion years ago, which used to be powerful in its initial stages, as this usually happens due to motion and convection inside the core. (With inputs from agencies)

What is inside the moon’s inner core? Here’s what scientists revealed

Earth's core is a gigantic ball of liquid metal and is located nearly 2,890 kilometres below us. Scientists have made a fascinating discovery in the outer core where they say a ring-like structure, similar to a doughnut is present. Research published in the journal Science Advances says that this ring is parallel to the equator.

Study co-author and Australian National University geophysicist, Prof Hrvoje Tkalčić says that it is not possible to reach the planet's core using existing technology. So they relied on seismic waves and looked at the forms generated by large earthquakes as they travelled through the Earth.

They compared the data generated by seismic detectors closer to the poles with results from nearer the Equator. They noticed that the waves slowed down near the ceiling, before the mantle. &nbsp;

“By understanding the geometry of the paths of the waves and how they traverse the outer core’s volume, we reconstructed their travel times through the Earth,” Tkalčić said.

“We realised that seismic waves slow down in the zone that mathematically is called a torus. To most people this looked like a doughnut," he said.

"Overall, the waves detected closer to the poles were travelling faster than those near the Equator."

<h2>Earth's core and magnetic field</h2>

He stressed that it was important to study the outer core since it is responsible for the magnetic field which protect Earth from the constant bombardment of charged particles from the sun.

Also Read:&nbsp;<a href="https://www.wionews.com/science/black-holes-are-creating-an-optical-illusion-in-the-early-universe-heres-how-754628">Black holes are creating an optical illusion in the early universe. Here's how</a>

The molten iron and nickel in the core has currents moving that act like a “giant dynamo” which generated and sustains the magnetic field. Tkalčić said the presence of this dynamo has confused scientists for years because other planets do not have it.&nbsp;

Earth's core is slightly larger than Mars. “We can think of it as a planet within our own planet,” Tkalčić said.

While the exact size of this structure is not known, it likely stretches a few hundred kilometres.

“We don’t know the exact thickness of the doughnut, but we inferred that it reaches a few hundred kilometres beneath the core-mantle boundary.”&nbsp;

It consists of lighter chemical elements such as silicon, sulphur, oxygen, hydrogen or carbon. 
&nbsp;

Earth's core is a gigantic ball of liquid metal and is located nearly 2,890 kilometres below us. Scientists have made a fascinating discovery in the outer core where they say a ring-like structure, similar to a doughnut is present.

Earth's core is a gigantic ball of liquid metal and is located nearly 2,890 kilometres below us. Scientists have made a fascinating discovery in the outer core where they say a ring-like structure, similar to a doughnut is present. Research published in the journal Science Advances says that this ring is parallel to the equator. Study co-author and Australian National University geophysicist, Prof Hrvoje Tkalčić says that it is not possible to reach the planet's core using existing technology. So they relied on seismic waves and looked at the forms generated by large earthquakes as they travelled through the Earth. They compared the data generated by seismic detectors closer to the poles with results from nearer the Equator. They noticed that the waves slowed down near the ceiling, before the mantle. “By understanding the geometry of the paths of the waves and how they traverse the outer core’s volume, we reconstructed their travel times through the Earth,” Tkalčić said. “We realised that seismic waves slow down in the zone that mathematically is called a torus. To most people this looked like a doughnut," he said. "Overall, the waves detected closer to the poles were travelling faster than those near the Equator." Earth's core and magnetic field He stressed that it was important to study the outer core since it is responsible for the magnetic field which protect Earth from the constant bombardment of charged particles from the sun. Also Read: Black holes are creating an optical illusion in the early universe. Here's how The molten iron and nickel in the core has currents moving that act like a “giant dynamo” which generated and sustains the magnetic field. Tkalčić said the presence of this dynamo has confused scientists for years because other planets do not have it. Earth's core is slightly larger than Mars. “We can think of it as a planet within our own planet,” Tkalčić said. While the exact size of this structure is not known, it likely stretches a few hundred kilometres. “We don’t know the exact thickness of the doughnut, but we inferred that it reaches a few hundred kilometres beneath the core-mantle boundary.” It consists of lighter chemical elements such as silicon, sulphur, oxygen, hydrogen or carbon.

A mysterious 'doughnut' is sitting in molten metal inside Earth's core

The latest study has confirmed that the Earth’s inner core is slowing down in relation to the surface of the planet. The decrease in speed started over 10 years ago - around 2010. This apparently happened for the first time since scientists developed the capacity to measure it.&nbsp;

The inner core is solid and made up of iron and nickel. It is a very hot and dense centre of our planet, with temperatures up to 5,500 degrees Celsius. The liquid iron-nickel outer core surrounds a solid iron-nickel spherical within it. The inner core is roughly the size of the moon and rests more than 3,000 miles beneath our feet.&nbsp;

Researchers can't visit or view it but they can study it using the seismic waves of earthquakes.&nbsp;

Also read:&nbsp;<a href="https://www.wionews.com/science/this-supernova-remained-brilliantly-bright-40-years-after-its-explosion-731437">This supernova remained brilliantly bright 40 years after its explosion</a>&nbsp;

Scientists at the University of Southern California have proven that the Earth's inner core is backtracking, meaning slowing down. The study, titled, "Inner core backtracking by seismic waveform change reversals", was published in Nature on Wednesday (Jun 12).&nbsp;

"The pattern of matches, together with previous studies, demonstrates that the inner core gradually super-rotated from 2003 to 2008, and then from 2008 to 2023 sub-rotated two to three times more slowly back through the same path," the researchers said.&nbsp;

John Vidale, Dean's Professor of Earth Sciences at the USC Dornsife College of Letters, Arts and Sciences, said as quoted by the official site: "When I first saw the seismograms that hinted at this change, I was stumped."&nbsp;

"But when we found two dozen more observations signaling the same pattern, the result was inescapable. The inner core had slowed down for the first time in many decades. Other scientists have recently argued for similar and different models, but our latest study provides the most convincing resolution," Vidale added.&nbsp;

Also read:&nbsp;<a href="https://www.wionews.com/science/new-species-of-pterosaur-discovered-using-100-million-year-old-fossilised-bones-731232">New species of pterosaur discovered using 100-million-year-old fossilised bones</a>&nbsp;

The official release mentioned that the inner core is considered to be reversing and backtracking relative to the planet's surface as a result of moving somewhat slower than the Earth's mantle for the first time in about 40 years.&nbsp;

This could eventually alter the entire planet's rotation, prolonging our days, but if there are any noticeable consequences, they will most likely be on the geomagnetic field.&nbsp;

Vidale also said that the backtracking of the inner core may alter the length of a day by fractions of a second. As quoted, he said, "It's very hard to notice, on the order of a thousandth of a second, almost lost in the noise of the churning oceans and atmosphere."&nbsp;

(With inputs from agencies)&nbsp;

The latest study has confirmed that the Earth’s inner core is slowing down in relation to the surface of the planet. The decrease in speed started over 10 years ago - around 2010.

The latest study has confirmed that the Earth’s inner core is slowing down in relation to the surface of the planet. The decrease in speed started over 10 years ago - around 2010. This apparently happened for the first time since scientists developed the capacity to measure it. The inner core is solid and made up of iron and nickel. It is a very hot and dense centre of our planet, with temperatures up to 5,500 degrees Celsius. The liquid iron-nickel outer core surrounds a solid iron-nickel spherical within it. The inner core is roughly the size of the moon and rests more than 3,000 miles beneath our feet. Researchers can't visit or view it but they can study it using the seismic waves of earthquakes. Also read: This supernova remained brilliantly bright 40 years after its explosion Scientists at the University of Southern California have proven that the Earth's inner core is backtracking, meaning slowing down. The study, titled, "Inner core backtracking by seismic waveform change reversals", was published in Nature on Wednesday (Jun 12). "The pattern of matches, together with previous studies, demonstrates that the inner core gradually super-rotated from 2003 to 2008, and then from 2008 to 2023 sub-rotated two to three times more slowly back through the same path," the researchers said. John Vidale, Dean's Professor of Earth Sciences at the USC Dornsife College of Letters, Arts and Sciences, said as quoted by the official site: "When I first saw the seismograms that hinted at this change, I was stumped." "But when we found two dozen more observations signaling the same pattern, the result was inescapable. The inner core had slowed down for the first time in many decades. Other scientists have recently argued for similar and different models, but our latest study provides the most convincing resolution," Vidale added. Also read: New species of pterosaur discovered using 100-million-year-old fossilised bones The official release mentioned that the inner core is considered to be reversing and backtracking relative to the planet's surface as a result of moving somewhat slower than the Earth's mantle for the first time in about 40 years. This could eventually alter the entire planet's rotation, prolonging our days, but if there are any noticeable consequences, they will most likely be on the geomagnetic field. Vidale also said that the backtracking of the inner core may alter the length of a day by fractions of a second. As quoted, he said, "It's very hard to notice, on the order of a thousandth of a second, almost lost in the noise of the churning oceans and atmosphere." (With inputs from agencies)

Earth's inner core rotation slowed for over a decade. It might impact your days

China has recently introduced its groundbreaking ocean-drilling vessel, the Mengxiang, designed to embark on a&nbsp;mission of penetrating the Earth's crust.

If successful, this&nbsp;would be&nbsp;humanity's first&nbsp;exploration into the upper mantle of the planet.

Crafted by the China Geological Survey in collaboration with over 150 research institutes and companies, the Mengxiang is a colossal ship with a cargo capacity of 33,000 tonnes.

Spanning 179 metres in length and 32.8 metres&nbsp;in width, the vessel can traverse 15,000 nautical miles and operate for 120 days per port call, according to the South China Morning Post.

Its robust stability and structure makes it resilient against the fiercest tropical cyclones, while its drilling capabilities allow it to reach an impressive depth of 11,000 metres below the ocean's surface.

Traditionally, human activities and scientific exploration have been confined to the Earth's crust, which has an average thickness of 15,000 metres.&nbsp;Beneath the crust lies the mantle, a pivotal layer connecting the surface to the core.

The Mengxiang aims to breach the Mohorovicic discontinuity, or Moho, located about 7,000 metres&nbsp;beneath the ocean floor, opening the door to previously unexplored scientific territories.

Also watch this report

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<h2>Historical attempts&nbsp;</h2>

Despite attempts since the 1960s by American scientists to breach the Moho and reach the mantle, the goal has remained elusive.

However, advancements in deep ocean drilling technology have provided valuable insights into the Earth's structure.

Rock samples from ultra-deep boreholes have unveiled crucial information about plate tectonics, oceanic crust evolution, ancient ocean climates, and seabed resources.

Speculations about life existing within the mantle abound, fueled by discoveries of organisms capable of withstanding extreme conditions. The mantle's composition, particularly peridotite, could produce energy for life forms.

<a href="https://www.wionews.com/science/earths-inner-core-might-have-stopped-and-changed-direction-check-what-happens-now-555556">Also read |&nbsp;Earth's inner core might have stopped and changed direction: Check out what happens now!</a>

However, skepticism exists, even as some scientists point to the presence of dormant microbes with slow metabolism in seabed rocks.

The recent trials of the Mengxiang primarily focused on testing its propulsion system, powered by a 30-megawatt station. Challenges, however, persist in reaching the targeted 11,000 metres&nbsp;beneath the water's surface, including high temperatures and pressures. Advanced drilling techniques, high-quality drill bits, and circulation systems are deemed necessary, requiring substantial time, money, and facing potential failure risks.

(With inputs from agencies)

&nbsp;

&nbsp;

China has recently introduced its groundbreaking ocean-drilling vessel, the Mengxiang, designed to embark on a mission of penetrating the Earth's crust. If successful, this would be humanity's first exploration into the upper mantle of the planet.

China has recently introduced its groundbreaking ocean-drilling vessel, the Mengxiang, designed to embark on a mission of penetrating the Earth's crust. If successful, this would be humanity's first exploration into the upper mantle of the planet. Crafted by the China Geological Survey in collaboration with over 150 research institutes and companies, the Mengxiang is a colossal ship with a cargo capacity of 33,000 tonnes. Spanning 179 metres in length and 32.8 metres in width, the vessel can traverse 15,000 nautical miles and operate for 120 days per port call, according to the South China Morning Post. Its robust stability and structure makes it resilient against the fiercest tropical cyclones, while its drilling capabilities allow it to reach an impressive depth of 11,000 metres below the ocean's surface. Traditionally, human activities and scientific exploration have been confined to the Earth's crust, which has an average thickness of 15,000 metres. Beneath the crust lies the mantle, a pivotal layer connecting the surface to the core. The Mengxiang aims to breach the Mohorovicic discontinuity, or Moho, located about 7,000 metres beneath the ocean floor, opening the door to previously unexplored scientific territories. Also watch this report Historical attempts Despite attempts since the 1960s by American scientists to breach the Moho and reach the mantle, the goal has remained elusive. However, advancements in deep ocean drilling technology have provided valuable insights into the Earth's structure. Rock samples from ultra-deep boreholes have unveiled crucial information about plate tectonics, oceanic crust evolution, ancient ocean climates, and seabed resources. Speculations about life existing within the mantle abound, fueled by discoveries of organisms capable of withstanding extreme conditions. The mantle's composition, particularly peridotite, could produce energy for life forms. Also read | Earth's inner core might have stopped and changed direction: Check out what happens now! However, skepticism exists, even as some scientists point to the presence of dormant microbes with slow metabolism in seabed rocks. The recent trials of the Mengxiang primarily focused on testing its propulsion system, powered by a 30-megawatt station. Challenges, however, persist in reaching the targeted 11,000 metres beneath the water's surface, including high temperatures and pressures. Advanced drilling techniques, high-quality drill bits, and circulation systems are deemed necessary, requiring substantial time, money, and facing potential failure risks. (With inputs from agencies)

China's ocean-drilling ship Mengxiang sets sail to reach earth's mantle

In a ground-breaking research conducted at Cardiff University in Wales, a researcher has tried to figure out when the universe’s first continents were formed.

Jane Greaves, an astronomy professor in the School of Physics and Astronomy, recently published her new research, titled “When Were the First Exocontinents?”

She asserts that the search for other habitable planets in our solar system can become more effective if the relation between life and continents is better understood.

In her research, Greaves says that it should be possible to calculate when the first continents formed in the universe by analysing the radioactive elements present in the core of the Earth. She also asserts that those radioactive elements came from neutron star collisions, thus paving the way to better analyse the universe through analysing our Earth’s mantle.

<h2>Relation between life and continents on a planet</h2>

Plate tectonics, while not necessarily essential for life, hold a crucial role in regulating Earth's temperature by dissipating heat from its core.

This thermal control prevents an excessive buildup of heat, which could harm Earth's protective magnetosphere. This also paves the way for the evolution of life.&nbsp;

Watch:&nbsp;Aliens: Are we looking in the wrong place?

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Furthermore, plate tectonics contribute to Earth's positioning in the habitable "Goldilocks Zone." Although early life on Earth emerged when plate tectonics were less active, they became vital for the persistence and evolution of complex life forms like humans.

Greaves's research aims to enhance the search for habitable exoplanets. If continents and the plate tectonics that give rise to them prove critical for life, then focusing our quest on rocky planets with plate tectonics can significantly improve our chances of discovering habitable worlds.&nbsp;

<h2>Understanding the core</h2>

Deep within Earth's core reside radioactive isotopes like Uranium-238, Thorium-232, and Potassium-40, which release heat as they undergo decay over geological timescales.&nbsp;

As per Greaves, we can dive into the details and history of our universe by analysing these elements.

<a href="https://www.wionews.com/science/breakthrough-google-develops-ai-tool-capable-of-predicting-harmful-genetic-mutations-637699">Also read:&nbsp;Breakthrough? Google develops AI tool capable of predicting harmful genetic mutations</a>

Her work provides a broader perspective in our quest to understand them. Her findings suggest that the appearance of continents on Earth represents the middle ground among various scenarios.

<h2>Tectonics on Earth</h2>

Earth's plate tectonics began roughly 3 billion years ago, about 9.5 billion years after the universe’s inception. Greaves indicates that continents formed on thin disk stars a staggering 2 billion years prior to Earth's appearance.&nbsp;

Additionally, her work suggests that, on most planets, the formation of continents occurs at a slower pace compared to Earth.&nbsp;

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In a ground-breaking research conducted at Cardiff University in Wales, a researcher has tried to figure out when the universe’s first continents were formed. Jane Greaves, an astronomy professor in the School of Physics and Astronomy, recently published her new research, titled “When Were the First Exocontinents?

In a ground-breaking research conducted at Cardiff University in Wales, a researcher has tried to figure out when the universe’s first continents were formed. Jane Greaves, an astronomy professor in the School of Physics and Astronomy, recently published her new research, titled “When Were the First Exocontinents?” She asserts that the search for other habitable planets in our solar system can become more effective if the relation between life and continents is better understood. In her research, Greaves says that it should be possible to calculate when the first continents formed in the universe by analysing the radioactive elements present in the core of the Earth. She also asserts that those radioactive elements came from neutron star collisions, thus paving the way to better analyse the universe through analysing our Earth’s mantle. Relation between life and continents on a planet Plate tectonics, while not necessarily essential for life, hold a crucial role in regulating Earth's temperature by dissipating heat from its core. This thermal control prevents an excessive buildup of heat, which could harm Earth's protective magnetosphere. This also paves the way for the evolution of life. Watch: Aliens: Are we looking in the wrong place? × Furthermore, plate tectonics contribute to Earth's positioning in the habitable "Goldilocks Zone." Although early life on Earth emerged when plate tectonics were less active, they became vital for the persistence and evolution of complex life forms like humans. Greaves's research aims to enhance the search for habitable exoplanets. If continents and the plate tectonics that give rise to them prove critical for life, then focusing our quest on rocky planets with plate tectonics can significantly improve our chances of discovering habitable worlds. Understanding the core Deep within Earth's core reside radioactive isotopes like Uranium-238, Thorium-232, and Potassium-40, which release heat as they undergo decay over geological timescales. As per Greaves, we can dive into the details and history of our universe by analysing these elements. Also read: Breakthrough? Google develops AI tool capable of predicting harmful genetic mutations Her work provides a broader perspective in our quest to understand them. Her findings suggest that the appearance of continents on Earth represents the middle ground among various scenarios. Tectonics on Earth Earth's plate tectonics began roughly 3 billion years ago, about 9.5 billion years after the universe’s inception. Greaves indicates that continents formed on thin disk stars a staggering 2 billion years prior to Earth's appearance. Additionally, her work suggests that, on most planets, the formation of continents occurs at a slower pace compared to Earth. WATCH WION LIVE HERE ×

When was the universe's first continent formed? Scientist offers clues

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What is inside the moon’s inner core? Here’s what scientists revealed

A mysterious 'doughnut' is sitting in molten metal inside Earth's core

Earth's inner core rotation slowed for over a decade. It might impact your days

China's ocean-drilling ship Mengxiang sets sail to reach earth's mantle

When was the universe's first continent formed? Scientist offers clues