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Earth and Mars’ foundational materials were initially abundant in moderately volatile elements.

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A new analysis of the metstones of magmatic iron challenges traditional theories about why Earth and Mars are depleted with moderately volatile elements.

Bendego met stone. Image credit: Jorge Andrade / CC by 2.0.

Medium volatile elements (MVEs) such as copper and zinc play an important role in planetary chemistry with essential elements of life, such as water, carbon, and nitrogen.

Understanding its origins provides important clues as to why the Earth has become a habitable world.

Earth and Mars contain significantly fewer MVEs than primitive metstones (chondrites), raising basic questions about the planetary layer.

This new study employs a new approach by analyzing iron meteorites (the metal core remnants of the earliest planetary building blocks) to reveal new insights.

“We’ve seen a lot of experience in the world,” said Dr. Damanveer Grewal, a researcher at Arizona State University.

“This discovery reconstructs our understanding of how the planet acquired its components.”

Until now, scientists believed that MVE was lost because they were not completely condensed in the early solar system or escaped during planetary differentiation.

However, new research reveals a different story. It is held by many MVEs on the first planet, suggesting that the building blocks of Earth and Mars later lost theirs.

Surprisingly, the authors discovered that many inner solar system planets retain abundance of MVEs like chondrites, and accretion continues despite being differentiated. It indicates that it has been saved.

This was not because Earth and Mars ancestors began to deplete with these elements, but instead occurred in the long history of collision growth, rather than incomplete condensation of solar nebulae or planet differentiation. Suggests that.

“Our work redefines how we understand the chemical evolution of planets,” Dr. Grewal said.

“It shows that the components of Earth and Mars were originally rich in these vital elements, but the intense collisions during the planet’s growth caused depletion.”

study Published in the journal Advances in Science.

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Damanveer S. Grewal et al. 2025. Enrichment of moderate volatile elements in first-generation planets of the inner solar system. Advances in Science 11 (6); doi:10.1126/sciadv.adq7848

Source: www.sci.news

New research suggests the moon could be older than initially estimated

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overview

  • New research suggests the moon may be older than many scientists thought.
  • This study suggests that the moon rock samples taken during the Apollo missions date back to an event in which the moon's surface melted, rather than the moment the moon formed.
  • Therefore, the authors believe that the Moon formed about 4.51 billion years ago, which is more than 100 million years earlier than the generally accepted estimate.

The moon may be more than 100 million years older than some scientists previously thought, according to a new study.

The study was published on Wednesday. journal naturechallenges long-held ideas The moon is thought to have formed about 4.35 billion years ago after an object the size of Mars crashed into the early Earth and created our natural satellite.

That timeline is based on analysis of lunar rock samples taken during NASA's Apollo mission. But new research shows that the moon formed much earlier, about 4.51 billion years ago, and then underwent a dramatic “remelting” phenomenon around the time other scientists thought the moon first formed. It suggests that you have experienced it.

According to the authors, the melting occurred because Earth's constant gravitational pull distorted the moon and made it extremely hot as it moved away from Earth. According to the study, this process altered the moon's surface and hid the moon's true age.

The study's lead author, Francis Nimmo, a professor in the Department of Earth and Planetary Sciences at the University of California, Santa Cruz, said the extreme heating caused the moon's surface to re-melt, effectively “resetting all the clocks” on the moon's rocks. 'There is a possibility.

“So moon rocks don't tell us when the moon formed, but they tell us when subsequent events that heated the moon occurred,” he says.

The scientific community has disagreed for decades about the exact age of the moon. Nimmo and his colleagues are not the first to offer older estimates. This new discovery adds to the growing consensus that there may be more to the moon's history than the Apollo samples revealed.

For example, planetary scientists have wondered how a massive collision occurred 4.35 billion years ago, when most large objects in the history of the solar system were thought to have already come together to form planets. I have had a hard time explaining why the moon was formed.

“Those who studied the Apollo samples had reasonable guesses about the moon's age, but those who modeled how the planets in our solar system formed are wondering why so much material still remains after 200 million years. “It was always difficult to explain why the solar system was still flying,” Nimmo said. “That's the way it is, and the two camps want different ages.”

The adjusted schedule by Nimmo's team may also help explain why. A mineral called zircon found on the moon It was discovered in Apollo's moon rock and is estimated to be approximately 4.5 billion years old. The moon's zircons, like other minerals on the moon, were thought to have crystallized during the moon's extreme temperatures, but their much older age has long puzzled scientists. .

In a new study, Nimmo and his colleagues suggest that the moon's overheating is the product of a process known as “tidal heating.”

“There are certain spots where the moon's orbit can be temporarily thrown off as it gets pushed aside,” Nimmo said. “During that time, the moon can be squeezed and stretched by Earth's gravity, which causes it to heat up.”

Similar tidal heating is thought to occur between Jupiter and its moons. a 2020 survey Researchers have discovered that the gas giant's gravity can stretch and squeeze some of its icy moons to the point where they heat up their interiors and melt rocks into magma. It is believed that this also applies to Jupiter's moon Io.

Recent and upcoming lunar missions could provide better insight into the moon's evolutionary history, Nimmo said. This includes China's Chang'e 6 mission, which collected samples from…

“The evolution of the solar system was very rapid. In just tens of millions of years, all the objects we know today were formed,” Munker said. “That's why we need very good temporal resolution for these very early events and why it's important to understand how the Earth-Moon system formed.”

Source: www.nbcnews.com

Astronomers Discover Fewer Potentially Hazardous Asteroids Near Earth than Initially Predicted

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astronomer using Zwicky Temporary Facility (ZTF) investigated. Taurus resonance groupa large interplanetary system containing Comet 2P/Encke, several meteor showers, and possibly numerous near-Earth asteroids.

This image taken by NASA's Spitzer Space Telescope shows comet 2P/Encke running along a pebble trail of its debris. Image credit: NASA / JPL-Caltech / University of Minnesota.

“We can take advantage of the unique opportunity that this asteroid swarm has to approach Earth to more efficiently search for celestial objects that may pose a threat to Earth,” said Dr. Kuanji Ye, an astronomer at the University of Maryland. ” he said.

“Our results suggest that the risk of impact from large asteroids in the Taurus group is much lower than we thought, which is good news for planetary defense.”

Prior to this study, astronomers had predicted that the Taurus resonance complex contained a significant number of large kilometer-sized space rocks, probably left behind by large objects up to 100 kilometers (62 miles) wide. I was guessing.

If a large object were to hit Earth, like the Chelyabinsk asteroid in 2013, it could cause regional damage.

Even larger objects can cause extinction-level events, like the asteroid that wiped out the dinosaurs more than 66 million years ago.

“Fortunately, we found that there are likely only a small number of asteroids in this large size class, perhaps only nine to 14, in this population,” Dr. Ye said.

“Judging by our findings, the parent object that first spawned the swarm was probably closer to 10 km (6.2 miles) in diameter, rather than a giant 100 km diameter object.”

“We still need to be cautious about asteroid impacts, but knowing this result will probably help us sleep better.”

The Taurus swarm holds important clues about planetary evolution, especially because of its association with Comet Encke.

This comet has the shortest orbital period of any known comet, at just 3.3 years.

It is also unusually large and dusty for a short-period comet that orbits the sun within 200 years.

Considering all available evidence, scientists believe that Encke has experienced significant fragmentation in the past and may continue to do so in the future.

“Studying the Taurus swarm helps us understand how small objects like comets and asteroids form and break up over time,” said Dr. Ye.

“Our research has implications not only for asteroid detection and planetary defense, but also for our broader understanding of the solar system's celestial bodies.”

The researchers presented their findings. findings this week's DPS56Annual Meeting of the Planetary Science Division of the American Astronomical Society.

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Yosenshi others. 2024. In search of potentially dangerous asteroids in the Taurus resonance group. DPS56

Source: www.sci.news

The abundance of ice deposits on the Moon is greater than initially believed

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Previous studies have found signs of ice in permanently shadowed regions near the moon’s south pole, including areas within the Cabeus, Howarth, Shoemaker, and Faustini craters. A new analysis of data from NASA’s Lunar Reconnaissance Orbiter (LRO) shows there is widespread evidence of water ice outside Antarctica, at least within a permanently shadowed region toward 77 degrees south latitude. Ta.

This figure shows the distribution of permanently shadowed regions (blue) toward the moon’s poles at 80 degrees south latitude. They are overlaid on a digital elevation map of the lunar surface (gray) from the Lunar Orbiter Laser Altimeter Instrument aboard NASA’s Lunar Reconnaissance Orbiter. Image credit: NASA / GSFC / Timothy P. McClanahan.

Ice may have been embedded in the lunar regolith by comet or meteor impacts, emitted as steam (gas) from the moon’s interior, or formed by chemical reactions between hydrogen in the solar wind and oxygen in the regolith. there is.

Permanently shadowed regions (PSRs) typically occur in topographic depressions near the moon’s poles.

Due to the low angle of the sun, these regions have not seen sunlight for billions of years and are constantly in extremely cold conditions.

Ice molecules are thought to be repeatedly stripped from the regolith by meteorites, cosmic radiation, or sunlight, traveling across the lunar surface and landing on the PSR, where they become trapped in the extreme cold.

The PSR’s continuously cold surface could store ice molecules near the surface for perhaps billions of years, accumulating in sediments large enough for mining.

“Our models and analysis show that the largest ice concentrations are near the coldest parts of the PSR below 75 Kelvin (minus 198 degrees Celsius, or minus 325 degrees Fahrenheit) and on poleward-facing slopes of the PSR. It is expected to occur near the base of the Dr. Timothy McClanahan, researcher at NASA Goddard Space Flight Center.

“It is not possible to accurately measure the volume of ice deposits in the PSR or determine whether they are buried beneath a dry layer of regolith.”

“However, we expect it to be 1 m for each surface.2 If present above these deposits, there should be at least about 5 liters of ice within the top meter of the surface compared to the surrounding area. ”

McClanahan and his colleagues used LRO’s Lunar Exploration Neutron Detector (LEND) instrument to detect signs of ice deposits by measuring moderately energetic “exothermal” neutrons.

Specifically, they used LEND’s Collimating Sensor for Exothermal Neutrons (CSETN), which has a fixed field of view of 30 km (18.6 miles) in diameter.

Neutrons are produced by high-energy galactic cosmic rays that come from powerful deep space events, such as exploding stars, and impact the moon’s surface, destroying regolith atoms and scattering subatomic particles called neutrons.

Neutrons originate from depths of up to about 1 meter (3.3 feet) and ping-pong through the regolith, colliding with other atoms. Some are guided into space and detected by LEND.

Since hydrogen has approximately the same mass as a neutron, neutrons lose relatively more energy in collisions with hydrogen than in collisions with the most common regolith elements.

Therefore, if hydrogen is present in the regolith, its concentration will correspondingly reduce the number of medium-energy neutrons observed.

“We hypothesized that if all PSRs had the same hydrogen concentration, CSETN should detect hydrogen concentrations proportionally depending on their area,” Dr. McClanahan said.

“Therefore, more hydrogen should be observed towards the larger area of the PSR.”

of findings this week, Planetary Science Journal.

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TP McClanahan others. 2024. Evidence of widespread hydrogen sequestration within the lunar south pole cold trap. planet. Science. J 5, 217; doi: 10.3847/PSJ/ad5b55

This article has been adapted from the original release by NASA.

Source: www.sci.news