Category Archives: Inner Solar System

Chemistry says Moon is proto-Earth’s mantle, relocated: the leading hypotheses for the origin of the Moon disproved

Two recent models for the formation of the moon, one that allows exchange through a silicate atmosphere (top), and another that creates a more thoroughly mixed sphere of a supercritical fluid (bottom), lead to different predictions for potassium isotope ratios in lunar and terrestrial rocks (right). Credit: Kun Wang Measurements of an element in Earth and Moon rocks have just disproved the leading hypotheses for the origin of the Moon. Tiny differences in the segregation of the isotopes of potassium between the Moon and Earth were hidden below the detection limits of analytical techniques until recently. But in 2015, Washington University in St. Louis geochemist Kun Wang, then the Harvard Origins of Life Initiative Prize postdoctoral fellow, and Stein Jacobsen, professor of geochemistry at Harvard University, developed a technique for analyzing these isotopes that can hit precisions 10 times better than the best previous method . Wang and Jacobsen now.
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Proof Mars Was Once Like Io

“There are only around 100 Martian meteorites in collections around the world, according to BBC News, but almost all of them are much younger than Black Beauty – dating from around 150 to 600 million years ago. Scientists were able to analyse the different minerals encased in the 7553 fragment – one of five found in the desert – and said it showed the volatile nature of Mars’ surface. “It contains zircons for which we measured an age of 4,428 ± 25 million years, which were later disturbed 1,712 ± 85 million years ago,” Prof Humayan wrote. He explained: “The crust of Mars must have differentiated really quickly, rather than gradually over time. There was a big volcanic episode all over the surface, which then crusted up, and after that the volcanism dropped dramatically.” Source:    .
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The Incredible Shrinking Mercury is Active After All

It’s small, it’s hot, and it’s shrinking. New NASA-funded research suggests that Mercury is contracting even today, joining Earth as a tectonically active planet. Images obtained by NASA’s MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft reveal previously undetected small fault scarps— cliff-like landforms that resemble stair steps. These scarps are small enough that scientists believe they must be geologically young, which means Mercury is still contracting and that Earth is not the only tectonically active planet in our solar system, as previously thought. The findings are reported in a paper in the October issue of Nature Geoscience. Small graben, or narrow linear troughs, have been found associated with small fault scarps (lower white arrows) on Mercury, and on Earth’s moon. The small troughs, only tens of meters wide (inset box and upper white arrows), likely resulted from the bending of the crust as it was uplifted, and must.
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‘Great Valley’ Found on Mercury

Using colorized topography, Mercury’s “great valley” (dark blue) and Rembrandt impact basin (purple, upper right) are revealed in this high-resolution digital elevation model merged with an image mosaic obtained by NASA’s MESSENGER spacecraft. Credits: NASA/JHUAPL/Carnegie Institution of Washington/DLR/Smithsonian Institution Scientists used stereo images from NASA’s MESSENGER spacecraft to create a high-resolution topo map that revealed the broad valley — more than 620 miles (1,000 kilometers) long — extending into the Rembrandt basin, one of the largest and youngest impact basins on Mercury. About 250 miles (400 kilometers) wide and 2 miles (3 kilometers) deep, Mercury’s great valley is smaller than Mars’ Valles Marineris, but larger than North America’s Grand Canyon and wider and deeper than the Great Rift Valley in East Africa. “Unlike Earth’s Great Rift Valley, Mercury’s great valley is not caused by the pulling apart of lithospheric plates due to plate tectonics; it is the result of the.
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The moon thought to play a major role in maintaining Earth’s magnetic field

The gravitational effects associated with the presence of the Moon and Sun cause cyclical deformation of the Earth’s mantle and wobbles in its rotation axis. This mechanical forcing applied to the whole planet causes strong currents in the outer core, which is made up of a liquid iron alloy of very low viscosity. Such currents are enough to generate the Earth’s magnetic field. Credit: Julien Monteux and Denis Andrault.   The Earth’s magnetic field permanently protects us from the charged particles and radiation that originate in the sun. This shield is produced by the geodynamo, the rapid motion of huge quantities of liquid iron alloy in the Earth’s outer core. To maintain this magnetic field until the present day, the classical model required the Earth’s core to have cooled by around 3,000° C over the past 4.3 billion years. Now, a team of researchers from CNRS and Université Blaise Pascal1.
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