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Categories: Engineering: Graphene, Space: Astrophysics

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Quasiparticles -- long-lived particle-like excitations -- are a cornerstone of quantum physics, with famous examples such as Cooper pairs in superconductivity and, recently, Dirac quasiparticles in graphene. Now, researchers have discovered quasiparticles in a classical system at room temperature: a two-dimensional crystal of particles driven by viscous flow in a microfluidic channel. Coupled by hydrodynamic forces, the particles form stable pairs -- a first example of classical quasiparticles, revealing deep links between quantum and classical dissipative systems.

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Scientists have discovered the first gamma-ray eclipses from a special type of binary star system using data from NASA's Fermi Gamma-ray Space Telescope. These so-called spider systems each contain a pulsar -- the superdense, rapidly rotating remains of a star that exploded in a supernova -- that slowly erodes its companion.

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The structure of two-dimensional titanium oxide brakes-up at high temperatures by adding barium; instead of regular hexagons, rings of four, seven and ten atoms are created that order aperiodically. A team has now solved the riddle of two-dimensional quasicrystal formation from metal oxides.

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The most sensitive telescope now searching for radio signals from cosmic dawn, an era around 200 million years after the Big Bang when stars ignited, has doubled its sensitivity, a new paper reports. While not yet detecting this radiation -- the redshifted 21-centimeter line -- they have put new limits on the elemental composition of galaxies during the Epoch of Reionization. Early galaxies seem to be low in metals, fitting the most popular theory of cosmic evolution.

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Mobile phone batteries with a lifetime up to three times longer than today's technology could be a reality thanks to a recent innovation.

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Space weather can interfere with spaceflight and the operation of satellites, but the phenomenon is very difficult to study on Earth because of the difference in gravity. Researchers effectively reproduced the type of gravity that exists on or near stars and other planets inside of a glass sphere measuring 3 centimeters in diameter, or about 1.2 inches. The achievement could help scientists overcome the limiting role of gravity in experiments that are intended to model conditions in stars and other planets.

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Astronomers used observations from the James Webb Space Telescope (JWST) to achieve the darkest ever view of a dense interstellar cloud. These observations have revealed the composition of a virtual treasure chest of ices from the early universe, providing new insights into the chemical processes of one of the coldest, darkest places in the universe as well as the origins of the molecules that make up planetary atmospheres.

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A startling analysis from Globe at Night -- a citizen science program -- concludes that stars are disappearing from human sight at an astonishing rate. The study finds that, to human eyes, artificial lighting has dulled the night sky more rapidly than indicated by satellite measurements.

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Research has revealed how supermassive black holes (SMBHs) are feeding off gas clouds which reach them by traveling hundreds of thousands of light years from one galaxy to another.

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Graphene-based olfactory sensors that can detect odor molecules based on the design of peptide sequences were recently demonstrated. The findings indicated that graphene field-effect transistors (GFETs) functionalized with designable peptides can be used to develop electronic devices that mimic olfactory receptors and emulate the sense of smell by selectively detecting odor molecules.

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Astronomers have released a gargantuan survey of the galactic plane of the Milky Way. The new dataset contains a staggering 3.32 billion celestial objects -- arguably the largest such catalog so far. The data for this unprecedented survey were taken with the Dark Energy Camera.

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Our solar system is estimated to be about 4.57 billion years old. Previous analyses of ancient meteorites have shown that minerals were created through chemical reactions with water as far back as 4.5 billion years ago. New findings from the Ryugu asteroid samples indicate that carbonates were forming from water-rock reactions several million years earlier, even closer to the solar system's beginnings.

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Recent research shows that magnetic fields can spontaneously emerge in a plasma if the plasma has a temperature anisotropy. This mechanism is known as the Weibel instability. This new research is the first to unambiguously observe the Weibel instability in the laboratory. It offers a possible solution to the problem of the origin of the microgauss-level magnetic fields that permeate the galaxies.

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Hundreds of millions of light-years away in a distant galaxy, a star orbiting a supermassive black hole is being violently ripped apart under the black hole's immense gravitational pull. As the star is shredded, its remnants are transformed into a stream of debris that rains back down onto the black hole to form a very hot, very bright disk of material swirling around the black hole, called an accretion disc. This phenomenon -- where a star is destroyed by a supermassive black hole and fuels a luminous accretion flare -- is known as a tidal disruption event (TDE), and it is predicted that TDEs occur roughly once every 10,000 to 100,000 years in a given galaxy.

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Understanding how dust grains form in interstellar gas could offer significant insights to astronomers and help materials scientists develop useful nanoparticles.

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A team has studied the relation between galaxy size and luminosity of some of the earliest galaxies in the universe taken by the James Webb Space Telescope, less than a billion years after the Big Bang.

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Black holes are gatherers, not hunters. They lie in wait until a hapless star wanders by. When the star gets close enough, the black hole's gravitational grasp violently rips it apart and sloppily devours its gasses while belching out intense radiation. Astronomers have recorded a star's final moments in detail as it gets gobbled up by a black hole.

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A new theory could explain the origin and properties of systems of rocky super-Earths and their relationship with the terrestrial planets of the solar system.

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Something is amiss in the Butterfly Nebula. When astronomers compared two exposures of this planetary nebula that had been taken by the Hubble Space Telescope in 2009 and 2020, they saw dramatic changes in the material within its 'wings.' Powerful winds are apparently driving complex alterations of material within the Butterfly Nebula, behavior not seen in planetary nebulae to date. The researchers want to understand how such activity is possible from what should be a 'sputtering, largely moribund star with no remaining fuel.'

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The most well-known forms of carbon include graphite and diamond, but there are other more exotic nanoscale allotropes of carbon as well. These include graphene and fullerenes, which are sp2 hybridized carbon with zero (flat-shaped) or positive (sphere-shaped) curvatures. Researchers now report the discovery of a new form of carbon formed by heating fullerenes with lithium nitride.