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Categories: Physics: Acoustics and Ultrasound, Space: Structures and Features

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A 'beautiful effect' predicted by quantum electrodynamics (QED) can explain the puzzling first observations of polarized X-rays emitted by a magnetar -- a neutron star featuring a powerful magnetic field, according to an astrophysicist.

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The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. In 2017, astronomers reported discovering a shadow sweeping across the face of a vast pancake-shaped gas-and-dust disk surrounding the red dwarf star. The shadow isn't from a planet, but from an inner disk slightly inclined relative to the much larger outer disk -- causing it to cast a shadow. One explanation is that an unseen planet's gravity is pulling dust and gas into the planet's inclined orbit. The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. Now, a second shadow -- playing a game of peek-a-boo -- has emerged in just a few years between observations stored in Hubble's MAST archive. This could be from yet another disk nestled inside the system. The two disks are likely evidence of a pair of planets under construction.

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Scientists have observed a star swallowing a planet for the first time. Earth will meet a similar fate in 5 billion years.

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Using ESO's Very Large Telescope (VLT), researchers have found for the first time the fingerprints left by the explosion of the first stars in the Universe. They detected three distant gas clouds whose chemical composition matches what we expect from the first stellar explosions. These findings bring us one step closer to understanding the nature of the first stars that formed after the Big Bang.

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Engineers have developed a stretchable ultrasonic array capable of serial, non-invasive, three-dimensional imaging of tissues as deep as four centimeters below the surface of human skin, at a spatial resolution of 0.5 millimeters. This new method provides a non-invasive, longer-term alternative to current methods, with improved penetration depth.

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The first building blocks of life on Earth may have formed thanks to eruptions from our Sun, a new study finds. A series of chemical experiments show how solar particles, colliding with gases in Earth's early atmosphere, can form amino acids and carboxylic acids, the basic building blocks of proteins and organic life.

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Couches, tables, sleeves and more can turn into a high-fidelity input device for computers using a new sensing system.

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Astronomers used NASA's James Webb Space Telescope to study a rocky exoplanet known as GJ 486 b. It is too close to its star to be within the habitable zone, with a surface temperature of about 800 degrees Fahrenheit (430 degrees Celsius). And yet, their observations show hints of water vapor.

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Astronomers have discovered a new 'tidal disruption event,' in which the center of a galaxy lights up as its supermassive black hole rips apart a passing star. The outburst is the closest tidal disruption event observed to date, and one of the first to be identified at infrared wavelengths.

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A team of Japanese astronomers used simultaneous ground-based and space-based observations to capture a more complete picture of a superflare on a star. The observed flare started with a very massive, high-velocity prominence eruption. These results give us a better idea of how superflares and stellar prominence eruptions occur.

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A new study looked at a known binary star (two stars orbiting around a mutual center of gravity), analyzing starlight obtained from a range of ground- and space-based telescopes. The researchers found that the stars, located in a neighboring dwarf galaxy called the Small Magellanic Cloud, are in partial contact and swapping material with each other, with one star currently 'feeding' off the other. They orbit each other every three days and are the most massive touching stars (known as contact binaries) yet observed.

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Astronomers have observed, in one image, the shadow of the black hole at the center of the galaxy Messier 87 (M87) and the powerful jet expelled from it. Thanks to this new image, astronomers can better understand how black holes can launch such energetic jets.

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Scientists have unlocked one of the biggest mysteries of quasars -- the brightest, most powerful objects in the Universe -- by discovering that they are ignited by galaxies colliding.

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In new 3D computer simulations, astrophysicists modeled black holes of varying masses and then hurled stars (about the size of our sun) past them to see what might happen. If they exist, intermediate-mass black holes likely devour wayward stars like a messy toddler -- taking a few bites and then flinging the remains across the galaxy.

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Astrophysicists have provided the most direct evidence yet that Dark Matter does not constitute ultramassive particles as is commonly thought but instead comprises particles so light that they travel through space like waves. Their work resolves an outstanding problem in astrophysics first raised two decades ago: why do models that adopt ultramassive Dark Matter particles fail to correctly predict the observed positions and the brightness of multiple images of the same galaxy created by gravitational lensing?

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Scientists carried out an analysis of hundreds of popular song recordings from 1946 to 2020 to determine the lead vocal to accompaniment ratio, or LAR. The study considered the four highest-ranked songs from the Billboard Hot 100 chart for each year and the results show that, contrary to expectations, the LAR for popular music decreased over the decades in question. This means that, relative to their bands, lead singers are getting quieter.

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Every giant was once a baby, though you may never have seen them at that stage of their development. NASA's James Webb Space Telescope has begun to shed light on formative years in the history of the universe that have thus far been beyond reach: the formation and assembly of galaxies. For the first time, a protocluster of seven galaxies has been confirmed at a distance that astronomers refer to as redshift 7.9, or a mere 650 million years after the big bang. Based on the data collected, astronomers calculated the nascent cluster's future development, finding that it will likely grow in size and mass to resemble the Coma Cluster, a monster of the modern universe.

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A research team has confirmed evidence of a previously unknown planet outside of our solar system, and they used machine learning tools to detect it. A recent study by the team showed that machine learning can correctly determine if an exoplanet is present by looking in protoplanetary disks, the gas around newly formed stars. The newly published findings represent a first step toward using machine learning to identify previously overlooked exoplanets.

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Why does it feel so difficult to shout upwind? The sensation is common enough to have found its way into an idiom about not being understood. Researchers wanted a scientific explanation for the phenomenon -- and there wasn't been one. They have now shown that our common sense understanding of this situation is wrong. It isn't harder to shout into the wind; it's just harder to hear yourself.

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Mechanically responsive molecular crystals are extremely useful in soft robotics, which requires a versatile actuation technology. Crystals driven by the photothermal effect are particularly promising for achieving high-speed actuation. However, the response (bending) observed in these crystals is usually small. Now, scientists address this issue by inducing large resonated natural vibrations in anisole crystals with UV light illumination at the natural vibration frequency of the crystal.