Keyword: lunarorigin
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Oct. 23 (UPI) -- Scientists now believe the moon could actually be around 40 million years older than initially believed, according to new research. The finding comes after a group of researchers reexamined a collection of dust collected from the lunar surface and brought back to Earth in 1972, the last time astronauts visited the moon. Scientists took an in-depth look at crystals embedded within the dust, which was returned to Earth as part of NASA's Apollo 17 mission. Researchers believe a massive collision of debris with Earth led to the creation of the moon. That impact took place around...
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Earth is far from a solid mass of rock. The outer layer of our planet – known as the lithosphere – is made up of more than 20 tectonic plates; as these gargantuan slates glide about the face of the planet, we get the movement of continents, and interaction at the boundaries, not least of which is the rise and fall of entire mountain ranges and oceanic trenches. Yet there's some debate over what causes these giant slabs of rock to move around in the first place. Amongst the many hypotheses put forward over the centuries, convection currents generated by...
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Think of the red bluffs and cliffs of the Grand Canyon as Earth's history textbook, explained Barra Peak, lead author of the new study and a graduate student in geological sciences at CU Boulder. If you scale down the canyon's rock faces, you can jump back almost 2 billion years into the planet's past. But that textbook is also missing pages: In some areas, more than 1 billion years' worth of rocks have disappeared from the Grand Canyon without a trace. It's a mystery that goes back a long way. John Wesley Powell, the namesake of today's Lake Powell, first...
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In our planet's early history, 720 to 640 million years ago, thick sheets of ice covered the majority of the surface, as the Earth was locked in a deep freeze. But explosive underwater volcanoes changed the chemistry of the Earth's oceans and were key to breaking the planet from its icy state, according to a new study. Researchers at the University of Southampton believe underwater volcanoes helped to thaw out "Snowball Earth", and even led to runaway chemical chain reactions, which created the conditions for an explosion of life on Earth. While much of the driving forces behind glaciation during...
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No boats required. In the distant future, most if not all of today's continents (brown fragments, depicted with current-day outlines) will assemble into a single landmass called Amasia (shown approximately 100 million years from now). Over the next few hundred million years, the Arctic Ocean and the Caribbean Sea will disappear, and Asia will crash into the Americas forming a supercontinent that will stretch across much of the Northern Hemisphere. That's the conclusion of a new analysis of the movements of these giant landmasses. Unlike in today's world, where a variety of tectonic plates move across Earth's surface carrying the...
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A group of University of Wyoming professors and students has identified an unusual belt of igneous rocks that stretches for over 2,000 miles from British Columbia, Canada, through Idaho, Montana, Nevada, southeast California and Arizona to Sonora, Mexico. “Geoscientists usually associate long belts of igneous rocks with chains of volcanoes at subduction zones, like Mount Shasta, Mount Hood, Mount St. Helens and Mount Rainer,” says Jay Chapman, an assistant professor in UW’s Department of Geology and Geophysics. “What makes this finding so interesting and mysterious is that this belt of igneous rocks is located much farther inland, away from the...
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The African LLSVP. (Ward et al., Geochemistry, Geophysics, Geosystems, 2020) NATURE Vast Fragments of an Alien World Could Be Buried Deep Within Earth Itself PETER DOCKRILL24 MARCH 2021 They are among the largest and strangest of all structures on Earth: huge, mysterious blobs of dense rock lurking deep within the lowermost parts of our planet's mantle. There are two of these gigantic masses – called the large low-shear-velocity provinces (LLSVPs) – with one buried under Africa, the other below the Pacific Ocean. These anomalies are so massive, they in turn breed their own disturbances, such as the large phenomenon currently...
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Explanation: Was the oldest known rock on Earth found on the Moon? Quite possibly. The story opens with the Apollo 14 lunar mission. Lunar sample 14321, a large rock found in Cone crater by astronaut Alan Shepard, when analyzed back on Earth, was found to have a fragment that was a much better match to Earth rocks than other Moon rocks. Even more surprising, that rock section has recently been dated back 4 billion years, making it older, to within measurement uncertainty, than any rock ever found on Earth. A leading hypothesis now holds that an ancient comet or asteroid...
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The South Pole of the Moon. (NASA GSFC Scientific Visualisation Studio) =========================================================================== A distant asteroid trailing in the gravitational wake of Mars has been observed in greater detail than ever before, and the close-up reveals a surprising resemblance – one that raises some interesting questions about the object's ancient origins. The asteroid in question, called (101429) 1998 VF31, is part of a group of trojan asteroids sharing the orbit of Mars. Trojans are celestial bodies that fall into gravitationally balanced regions of space in the vicinity of other planets, located 60 degrees in front of and behind the planet. Most...
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The paper, titled Distinct oxygen isotope compositions of the Earth and Moon, may challenge the current understanding of the formation of the Moon. Previous research led to scientists to develop the Giant Impact Hypothesis suggesting the Moon was formed from debris following a giant collision between early-Earth and a proto-planet named Theia. The Earth and Moon are geochemically similar. Samples returned from the Moon from the Apollo missions showed a near-identical composition in oxygen isotopes. Although the Giant Impact Hypothesis can nicely explain many of the geochemical similarities between Earth and Moon, the extreme similarity in oxygen isotopes has been...
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Astronomers have found that the majority of meteorites that regularly fall into Earth's atmosphere today are the result of an asteroid collision that took place 466 million years ago. Using chemical analysis from rock samples around the world, the team discovered that before that colossal collision, Earth experienced impacts from many different types of meteorite, meaning that our planet's history with meteorites is far more complex than we thought. After examining the chemical makeup of these chrome-spinels, the team found that 34 percent of the pre-collision micrometeorites were primitive achondrites, a type of meteorite that only makes up 0.45 percent...
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Somebody alert Jeff Bezos: the Moon is shrinking. According to a new research study, the Moon may be shrinking as it experiences lunar quakes, known as "moonquakes." Researchers analyzed 28 moonquakes from 1969 to 1977 and came up with the startling observation that eight of the quakes came from "true tectonic activity — the movement of crustal plates," as opposed to impacts from asteroids or rumblings inside the celestial satellite. “We found that a number of the quakes recorded in the Apollo data happened very close to the faults seen in the [NASA’s Apollo and Lunar Reconnaissance Orbiter missions] LRO...
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There are a number of theories about where the moon came from. Our best guess is that it was formed when the Earth was hit by a large object known as Theia. The impact threw up huge amounts of debris into orbit, which eventually coalesced to form the moon. There’s a problem with this theory. The mathematical models show that most of the material that makes up the moon should come from Theia. But samples from the Apollo missions show that most of the material on the moon came from Earth. A paper out earlier this week in Nature Geoscience...
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Planet Earth doesn't have a birth certificate to record its formation, which means scientists spent hundreds of years struggling to determine the age of the planet. By dating the rocks in Earth's ever-changing crust, as well as the rocks in Earth's neighbors, such as the moon and visiting meteorites, scientists have calculated that Earth is 4.54 billion years old, with an error range of 50 million years. How old are your rocks? Scientists have made several attempts to date the planet over the past 400 years. They've attempted to predict the age based on changing sea levels, the time it...
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A chunk of Earth that could be 4.1 billion years old and is described as the planet's "oldest rock," may have been found and dug up on the Moon by Apollo astronauts, according to a new study. The possible relic was discovered and dug up in 1971 and scientists believe that it was sent off Earth, thanks to a powerful impact, possibly an asteroid or a comet. After colliding with the Moon (which at the time was three times closer to the Earth than it is now), it mixed with other lunar surface materials. "It is an extraordinary find that helps paint...
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If you ever find yourself at a cocktail party of astrophysicists and don't know what to say, try this: "But what about the angular momentum?" No matter what the topic of conversation, you'll be guaranteed to sound erudite. Nearly every field of astronomy, from galaxy formation to star formation, has an "angular momentum problem." Nothing in the cosmos ever seems to spin or orbit at the rate it should. The moon is no exception. It is the flywheel to end all flywheels; if its orbital angular momentum were transferred to Earth's axial rotation, our planet would come close to spinning ...
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Russell Mapes, a graduate student from Grass Valley, Calif., ...explains that these sediments of eastern origin were washed down from a highland area that formed in the Cretaceous Period, between 65 million and 145 million years ago, when the South American and African tectonic plates separated and passed each other. That highland tilted the river's flow westward, sending sediment as old as 2 billion years toward the center of the continent. A relatively low ridge, called the Purus Arch, which still exists, rose in the middle of the continent, running north and south, dividing the Amazon's flow - eastward toward...
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An intense temblor in Mexico was just the latest example of an enigmatic type of earthquake with highly destructive potential On September 7, 2017, a magnitude 8.2 earthquake struck southern Mexico, killing dozens and injuring hundreds. While earthquakes are common enough in the region, this powerful event wasn’t any run-of-the-mill tremor. That’s because part of the roughly 37-mile-thick tectonic plate responsible for the quake completely split apart, as revealed by a new study in Nature Geoscience. This event took place in a matter of tens of seconds, and it coincided with a gargantuan release of energy. “If you think of...
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If you simply flew up into space and sawed the moon in half with a giant hacksaw, most likely, nothing would happen. This is because gravitational force would hold the two halves together, sort of like a couple of magnets. But what if you were able to get a couple of giant crowbars and put a person on the other side and then count to 3 and totally separate the two halves of the moon? With enough strength applied, you could theoretically push the two halves far enough apart where the gravitational force no longer pulls them together and now...
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describes how the researchers created a method to rewind Earth’s clock by hundreds of millions of years. The system allowed the team to paint a rough picture of what a day on Earth might have been like over a billion years in the past, and better explain the evidence of climate shifts that have been observed in ancient rocks. The researchers note that if you take the timeline back far enough, looking 1.5 billion years in the past, the Moon would have been close enough that Earth’s gravity would have destroyed it. That obviously didn’t happen, but since the Moon...
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