Keyword: bobyirka
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A pair of economists, one with the University of Calgary, the other, the University of California, along with a civil engineer from Carnegie Mellon University, is suggesting in a Comment piece in the journal Nature, that electric vehicles (EVs) need to be lighter if they are to replace gasoline-powered vehicles. In their paper, Blake Shaffer, Maximilian Auffhammer and Constantine Samaras suggest that the added weight of EVs makes them less safe and less efficient and therefore less economical. In their paper, the authors note that climate change has put EVs on a path to replace cars powered by gasoline. But...
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Professional biologist and amateur mathematician Aubrey de Grey has partially solved the Hadwiger-Nelson problem, which has vexed mathematicians since 1950. He has published a paper describing the solution on the arXiv preprint server. The Hadwiger-Nelson problem came about when Edward Nelson and Hugo Hadwiger wondered about the smallest number of colors necessary to color all of the points on a graph, with no two connected points using the same color. Over the years, mathematicians have attacked the problem, and have narrowed the possibilities down to four, five, six or seven. Now, de Grey has eliminated the possibility of four colors...
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...Earth was bombarded on a regular basis during its formative years -- by meteorites and other space rocks. Some of those collisions left behind evidence that is still observable today in the form of craters. One of them is Mistastin Lake crater located in Labrador Canada, which is approximately 28 kilometers across, suggesting that the object that struck the Earth there was large. The researchers dated the collision that caused the crater back to approximately 38 million years ago... In studying the crater, the researchers found evidence of zircon, a common mineral, being changed into cubic zirconia. Prior work with...
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A team of researchers with members from Singapore, the U.S., Thailand and Laos has concluded that the impact point of a meteorite that struck the Earth approximately 790,000 years ago lies buried beneath a volcanic field in southern Laos. In their paper published in Proceedings of the National Academy of Sciences, the group outlines four lines of evidence that point to the Bolaven volcanic field as the likely site of the meteorite strike. Prior research has shown that approximately 790,000 years ago, a large meteorite (the largest known young meteorite impact) struck Earth in the Eastern Hemisphere. So great was...
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A trio of researchers at the University of California has found evidence that suggests there is far more ice on the surface of the moon than has been thought. In their paper published in the journal Nature Geoscience, Lior Rubanenko, Jaahnavee Venkatraman and David Paige describe their study of similarities between ice on Mercury and shadowed regions on the moon and what they found. Prior researchers using data from the Arecibo Observatory and also NASA's MESSENGER spacecraft found that there are cratered areas on Mercury's poles that appear shadowed from Earth. Data from the LRO probe that was intentionally crashed...
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Abstract The asteroid belt contains less than a thousandth of Earth's mass and is radially segregated, with S-types dominating the inner belt and C-types the outer belt. It is generally assumed that the belt formed with far more mass and was later strongly depleted. We show that the present-day asteroid belt is consistent with having formed empty, without any planetesimals between Mars and Jupiter's present-day orbits. This is consistent with models in which drifting dust is concentrated into an isolated annulus of terrestrial planetesimals. Gravitational scattering during terrestrial planet formation causes radial spreading, transporting planetesimals from inside 1 to 1.5...
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A team of researchers working at Argonne National Laboratory, in Illinois, has found a way to dramatically reduce friction between two macroscopic scale surfaces—to near zero. In their paper published in the journal Science, the team describes how they accidently discovered the method and why they believe it might be useful for real world applications. As most people are aware, friction causes energy loss and wear and tear on mechanical parts—lubricants such as oil are used to help reduce friction and to dissipate heat, but scientists would really like to find a way to prevent it from happening in the...
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Modern science has held that islands such as Cypress and Crete were first inhabited by seafaring humans approximately 9,000 years ago by agriculturists from the late Neolithic period. Simmons writes that research over the past 20 years has cast doubt on that assumption however and suggests that it might be time to rewrite the history books. He cites evidence such as pieces of obsidian found in a cave in mainland Greece that were found to have come from Melos, an island in the Aegean Sea and were dated at 11,000 years ago as well as artifacts from recent digs on...
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Airplane maker Boeing has unveiled what it calls the "The Lightest Metal Ever"—called microlattice, the material is a construct that is 99.99 per cent air. It has been developed by Boeing's HRL Laboratories along with colleagues at the University of California and the California Institute of Technology. The material has been developed as a way to reduce weight on airplanes or even rockets—a paper describing the development of the material was written by the team and published in the journal Science back in 2011—though the researchers have not yet revealed what sort of changes have been made since that time....
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