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Categories: Engineering: Graphene, Space: Structures and Features

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Discovered in 1912, cosmic rays have been studied extensively and our current understanding of them is compiled into what is called the Standard Model. Recently, this understanding has been challenged by the detection of unexpected spectral structures in the cosmic ray proton energy spectrum. Now, scientists take this further with high-statistics and low-uncertainty measurement of these protons over a broader energy range using the CALorimetric Electron Telescope, confirming the presence of such structures.

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Astronomers may have discovered the ancient chemical remains of the first stars to light up the Universe. Using an innovative analysis of a distant quasar observed by the 8.1-meter Gemini North telescope on Hawai'i, the scientists found an unusual ratio of elements that, they argue, could only come from the debris produced by the all-consuming explosion of a 300-solar-mass first-generation star.

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Using the James Webb Space Telescope (JWST), researchers have identified the most distant globular clusters ever discovered. These dense groups of millions of stars may be relics that contain the first and oldest stars in the universe. The early analysis of Webb's First Deep Field image depicts some of the universe's earliest galaxies.

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The first map of the 'galactic underworld' -- a chart of the corpses of once massive suns that have since collapsed into black holes and neutron stars -- has revealed a graveyard that stretches three times the height of the Milky Way, and that almost a third of the objects have been flung out from the galaxy altogether.

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Astronomers have assembled the largest-ever compilation of high-precision galaxy distances, called Cosmicflows-4.

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Using data from the Gaia space telescope, a team has shown that large parts of the Milky Way's outer disk vibrate. The ripples are caused by a dwarf galaxy, now seen in the constellation Sagittarius, that shook our galaxy as it passed by hundreds of millions of years ago.

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Researchers have demonstrated how a nanoscale layer of superconducting niobium nitride (NbNx) can be grown directly onto aluminum nitride (AIN). The arrangement of atoms, nitrogen content, and electrical conductivity were found to depend on growth conditions, particularly temperature, and the spacing of atoms in the two materials was sufficiently compatible to produce flat layers. The structural similarity between NbNx and AIN will facilitate the integration of superconductors into semiconductor optoelectronic devices.

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The carrier concentration and conductivity in p-type monovalent copper semiconductors can be significantly enhanced by adding alkali metal impurities. Doping with isovalent and larger-sized alkali metal ions effectively increased the free charge carrier concentration, and the mechanism was unraveled by their theoretical calculations. Their carrier doping technology enables high carrier concentration and high mobility p-type thin films to be prepared from the solution process, with photovoltaic device applications.

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Astronomers have developed a new technique to identify small planets hidden in protoplanetary disks.

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Astrophysicists show how and when specific particles form and offers clues to questions that have troubled scientists since the 1940s.

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Researchers demonstrated a topological insulator device that opens the way towards observing the quantum anomalous Hall effect. Because the currents generated are resistant to scattering, but very sensitive to applied magnetic fields, they may be used for reducing power consumption in computing applications.

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A new simulation conducted on the world's most powerful supercomputer dedicated to astronomy has produced a testable scenario to explain the appearance of the bar of the Milky Way. Comparing this scenario to data from current and future space telescopes will help clarify the evolution of our home Galaxy.

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Of all known planets, Earth is as friendly to life as any planet could possibly be -- or is it? If Jupiter's orbit changes, a new study shows Earth could be more hospitable than it is today.

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Early in its history, shortly after the Big Bang, the universe was filled with equal amounts of matter and 'antimatter' -- particles that are matter counterparts but with opposite charge. But then, as space expanded, the universe cooled. Today's universe is full of galaxies and stars which are made of matter. Where did the antimatter go, and how did matter come to dominate the universe? This cosmic origin of matter continues to puzzle scientists. Physicists have now opened a new pathway for probing the cosmic origin of matter by invoking the 'cosmological collider.'

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Stars are the machines that sculpt the universe, yet scientists don't fully know how they form. To understand the frenzied 'baby boom' of star birth that occurred early in the universe's history, researchers turned to the Small Magellanic Cloud, a satellite galaxy of the Milky Way. This nearby galaxy has a simpler chemical composition than the Milky Way, making it similar to the galaxies found in the younger universe, when heavier elements were more scarce. This allows it to serve as a proxy for the early universe. Two separate studies -- the first with the Hubble Space Telescope, and the second with the European Southern Observatory's Very Large Telescope -- recently came to the same conclusion. Using different methods, the independent teams found young stars spiraling into the center of a massive star cluster called NGC 346 in the Small Magellanic Cloud. This river-like motion of gas and stars is an efficient way to fuel star birth, researchers say. The teams' results show that the process of star formation in the Small Magellanic Cloud is similar to that in our own Milky Way.

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A new study suggests that many more planets may have large amounts of water than previously thought--as much as half water and half rock. The catch? All that water is probably embedded in the rock, rather than flowing as oceans or rivers on the surface.

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Astronomers have just announced the discovery of two 'super-Earth' planets orbiting LP 890-9, a small, cool star located about 100 light-years from Earth.

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Physicists have demonstrated a new magnetized state in a monolayer of tungsten ditelluride. This material of one-atom thickness has an insulating interior but a conducting edge, which has important implications for controlling electron flow in nanodevices.

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Jupiter-sized planets can be stolen or captured by massive stars in the densely populated stellar nurseries where most stars are born, a new study has found.

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Physicists and astronomers have studied gamma rays caused by the Sagittarius Dwarf, a small neighboring galaxy of our Milky Way. They showed that all the observed gamma radiation can be explained by millisecond pulsars, and can therefore not be interpreted as a smoking gun signature for the presence of dark matter.