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Categories: Physics: Acoustics and Ultrasound, Space: Exploration
Published How secure are voice authentication systems really?
(via sciencedaily.com) Original source Computer scientists have discovered a method of attack that can successfully bypass voice authentication security systems with up to a 99% success rate after only six tries.
Published Researchers use ultrasound to control orientation of small particles
(via sciencedaily.com) Original source Acoustic waves may be able to control how particles sort themselves. While researchers have been able to separate particles based on their shape -- for example, bacteria from other cells -- for years, the ability to control their movement has remained a largely unsolved problem, until now. Using ultrasound technology and a nozzle, researchers have separated, controlled and ejected different particles based on their shape and various properties.
Published Wind farm noise exposure doesn't wake people up from their slumber more than road traffic noise
(via sciencedaily.com) Original source Short exposure to wind farm and road traffic noise triggers a small increase in people waking from their slumber that can fragment their sleep patterns, according to new research. But importantly, the new study also shows that wind farm noise isn't more disruptive to sleep than road traffic, which was a little more disruptive at the loudest audio level but not at more common levels. Sleep researchers have studied the impact of exposure to wind farm noise during sleep in three new scientific publications to better understand its impact.
Published First detection of crucial carbon molecule
(via sciencedaily.com) Original source Scientists detect a new carbon compound in space for the first time. Known as methyl cation (pronounced cat-eye-on) (CH3+), the molecule is important because it aids the formation of more complex carbon-based molecules. Methyl cation was detected in a young star system, with a protoplanetary disk, known as d203-506, which is located about 1,350 light-years away in the Orion Nebula.
Published Einstein and Euler put to the test at the edge of the Universe
(via sciencedaily.com) Original source The cosmos is a unique laboratory for testing the laws of physics, in particular those of Euler and Einstein. Euler described the movements of celestial objects, while Einstein described the way in which celestial objects distort the Universe. Since the discovery of dark matter and the acceleration of the Universe's expansion, the validity of their equations has been put to the test: are they capable of explaining these mysterious phenomena? A team has developed the first method to find out. It considers a never-before-used measure: time distortion.
Published When soft spheres make porous media stiffer
(via sciencedaily.com) Original source Porous media such as concrete physically represent a spherical packing of different components -- in this case cement, rock and water. The mechanical properties of such mixtures are still difficult to calculate due to their discretized nature. A team has now been able to investigate an unexpected property of mixtures of granular media consisting of soft and stiff spherical particles. For this purpose, a combination of ultrasound investigations and X-ray computed tomographic imaging was employed, allowing a three-dimensional (3D) characterization and evaluation. The discovery could contribute to safer future building in earthquake zones.
Published Never-before-seen way to annihilate a star
(via sciencedaily.com) Original source Astronomers studying a powerful gamma-ray burst, may have detected a never-before-seen way to destroy a star. Unlike most GRBs, which are caused by exploding massive stars or the chance mergers of neutron stars, astronomers have concluded that this GRB came instead from the collision of stars or stellar remnants in the jam-packed environment surrounding a supermassive black hole at the core of an ancient galaxy.
Published Groundwork for future ultra-precise timing links to geosynchronous satellites
(via sciencedaily.com) Original source Scientists have demonstrated a capability long sought by physicists: transmitting extremely precise time signals through the air between far-flung locations at powers that are compatible with future space-based missions. The results could enable time transfer from the ground to satellites in geosynchronous orbit with femtosecond precision -- 10,000 times better than the existing state-of-the-art satellite approaches. It also would allow for successful synchronization using the bare minimum timing signal strength, which would make the system highly robust in the face of atmospheric disturbances.
Published Detection of an echo emitted by our Galaxy's black hole 200 years ago
(via sciencedaily.com) Original source An international team of scientists has discovered that Sagittarius A* (Sgr A*), the supermassive black hole at the centre of the Milky Way, emerged from a long period of dormancy some 200 years ago. The team, led by Frédéric Marin, a CNRS researcher at the Astronomical Strasbourg Observatory (CNRS/University of Strasbourg), has revealed the past awakening of this gigantic object, which is four million times more massive than the Sun. Their work is published in Nature on 21 June.
Published Jupiter's moon Europa may have had a slow evolution
(via sciencedaily.com) Original source Europa may have a metamorphic origin for the ocean. While some scientists speculated this, a research team shows that if Europa indeed formed from hydrated rocks (i.e., rocks have hydrogen and oxygen), then enough of Europa's interior should get hot enough to release water directly from the hydrated rocks to form the ocean and ice shell.
Published Researchers demystify the unusual origin of the Geminids meteor shower
(via sciencedaily.com) Original source Princeton researchers used observations from NASA's Parker Solar Probe mission to deduce that it was likely a violent, catastrophic event -- such as a high-speed collision with another body or a gaseous explosion -- that created the Geminids meteoroid stream. Mysteries surrounding the origin of the Geminids have long fascinated scientists because, while most meteor showers are created when a comet emits a tail of ice and dust, the Geminids stem from an asteroid -- a chunk of rock that normally does not produce a tail. Until now, this unusual meteoroid stream had only been studied from Earth.
Published A 'spy' in the belly
(via sciencedaily.com) Original source To ensure that wounds remain tightly sealed in the abdomen after surgery, researchers have developed a patch with a sensor function. The polymer patch warns before the occurrence of dangerous leaks on sutures in the gastrointestinal tract take hold, while closes the areas on its own. A new material now enables a fast, easy and non-invasive leak diagnosis.
Published Scientists report 'benchmarks' for extreme space weather
(via sciencedaily.com) Original source Extreme space weather threatens vital satellites orbiting the Earth, including the Global Navigation Satellite Systems (GNSS) which pass through the heart of the outer radiation belt. New research has now determined a series of benchmarks for the likely severity of extreme space weather events in GPS orbit.
Published Astronomers discover new link between dark matter and clumpiness of the universe
(via sciencedaily.com) Original source Researchers reveal a theoretical breakthrough that may explain both the nature of invisible dark matter and the large-scale structure of the universe known as the cosmic web. The result establishes a new link between these two longstanding problems in astronomy, opening new possibilities for understanding the cosmos. The research suggests that the 'clumpiness problem,' which centres on the unexpectedly even distribution of matter on large scales throughout the cosmos, may be a sign that dark matter is composed of hypothetical, ultra-light particles called axions. The implications of proving the existence of hard-to-detect axions extend beyond understanding dark matter and could address fundamental questions about the nature of the universe itself.
Published A scorching-hot exoplanet scrutinized by astronomers
(via sciencedaily.com) Original source Through the Gemini-North Telescope in Hawai'i, the chemical composition of WASP-76 b is revealed in unprecedented detail, giving new insights also into the composition of giant planets.
Published Sun's coldest region stores secret to heating million-degree corona
(via sciencedaily.com) Original source Researchers have unveiled the discovery of intense wave energy from a relatively cool, dark and strongly magnetized plasma region on the Sun, capable of traversing the solar atmosphere and maintaining temperatures of a million degrees Kelvin inside the corona. Researchers say the finding is the latest key to unraveling a host of related mysteries pertaining to Earth's nearest star.
Published Key building block for life found at Saturn's moon Enceladus
(via sciencedaily.com) Original source The search for extraterrestrial life in our solar system just got more exciting. A team of scientists has discovered new evidence that the subsurface ocean of Saturn's moon Enceladus contains a key building block for life. The team directly detected phosphorus in the form of phosphates originating from the moon's ice-covered global ocean using data from NASA's Cassini mission. Cassini explored Saturn and its system of rings and moons for over 13 years.
Published Pass the salt: This space rock holds clues as to how Earth got its water
(via sciencedaily.com) Original source The discovery of tiny salt grains in a sample from an asteroid provides strong evidence that liquid water may be more common in the solar system than previously thought.
Published DESI early data release holds nearly two million objects
(via sciencedaily.com) Original source The first batch of data from the Dark Energy Spectroscopic Instrument is now available for researchers to explore. Taken during the experiment's 'survey validation' phase, the data include distant galaxies and quasars as well as stars in our own Milky Way.
Published A new Tatooine-like multi-planetary system identified
(via sciencedaily.com) Original source An international team of astronomers has announced the second-ever discovery of a multiplanetary circumbinary system.