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Archive for the ‘space’ category: Page 299

Nov 4, 2022

Astronomers get a rare glimpse of the exposed core of a star

Posted by in categories: chemistry, physics, space

Sometimes astrophysics gets super weird.


A recent study of the star’s surface, published in the journal Nature Astronomy, says that we’re seeing Gamma Columbae in a short, deeply weird phase of a very eventful stellar life, one that lets astronomers look directly into the star’s exposed heart.

What’s New – The mix of chemical elements on the surface of Gamma Columbae look like the byproducts of nuclear reactions that should be buried in the depths of a massive star, not bubbling on its surface.

Nov 4, 2022

Scientists Discover Huge ‘Extragalactic Structure’ in Hidden Region of Space

Posted by in category: space

The obscured “zone of avoidance” in space is a place of mystery, and scientists are peering at what’s inside it.

Nov 3, 2022

AI Helped Design a Clear Window Coating That Can Cool Buildings Without Using Energy

Posted by in categories: climatology, robotics/AI, space, sustainability

Demand is growing for effective new technologies to cool buildings, as climate change intensifies summer heat. Now, scientists have just designed a transparent window coating that could lower the temperature inside buildings, without expending a single watt of energy. They did this with the help of advanced computing technology and artificial intelligence. The researchers report the details today (November 2) in the journal ACS Energy Letters.

Cooling accounts for about 15% of global energy consumption, according to estimates from previous research studies. That demand could be lowered with a window coating that could block the sun’s ultraviolet and near-infrared light. These are parts of the solar spectrum that are not visible to humans, but they typically pass through glass to heat an enclosed room.

Energy use could be even further reduced if the coating radiates heat from the window’s surface at a wavelength that passes through the atmosphere into outer space. However, it’s difficult to design materials that can meet these criteria simultaneously and at the same time can also transmit visible light, This is required so they don’t interfere with the view. Eungkyu Lee, Tengfei Luo, and colleagues set out to design a “transparent radiative cooler” (TRC) that could do just that.

Nov 3, 2022

Neutrino Astronomy Enters a New Era

Posted by in categories: particle physics, space

Using the IceCube Neutrino Observatory in Antarctica, researchers have found significant evidence of a cosmic source of high-energy neutrinos.

Nov 3, 2022

Explaining Mercury’s Superconductivity, 111 Years Later

Posted by in categories: materials, space

In 1911, physicist Heike Kamerlingh Onnes used liquid helium—whose production method he invented—to cool mercury to a few kelvins, discovering that its electrical resistance dropped to nil. Although mercury was later found to be a “conventional” superconductor, no microscopic theory so far managed to fully explain the metal’s behavior and to predict its critical temperature TC. Now, 111 years after Kamerlingh Onnes’ discovery, theorists have done just that. Their first-principles calculations accurately predict mercury’s TC but also pinpoint theoretical caveats that could inform searches for room-temperature superconductors [1].

Mercury is an exception among conventional superconductors, most of which can be successfully described with state-of-the-art density-functional-theory methods. To tackle mercury’s unique challenges, Gianni Profeta of the University of L’Aquila, Italy, and colleagues scrutinized all physical properties relevant for conventional superconductivity, which is mediated by the coupling of electrons to phonons. In particular, the researchers accounted for previously neglected relativistic effects that alter phonon frequencies, they improved the description of electron-correlation effects that modify electronic bands, and they showed that mercury’s d-electrons provide an anomalous screening effect that promotes superconductivity by reducing Coulomb repulsion between superconducting electrons. With these improvements, their calculations delivered a TC prediction for mercury only 2.5% lower than the experimental value.

The new understanding of the oldest superconductor will find a place in textbooks but may also offer valuable lessons for superconductivity research, says Profeta. A promising material-by-design approach involves “high-throughput” computations that screen millions of theoretical material combinations to suggest those that could be conventional superconductors close to ambient conditions. “If we don’t include subtle effects similar to those relevant for mercury, these computations may overlook many interesting materials or err in their critical temperature predictions by hundreds of kelvins,” he says.

Nov 3, 2022

Top What If Scenarios Recap

Posted by in categories: education, space

Let’s hangout and recap some of our most watched What If scenarios.

Get our 100 best episodes in one mind-blowing book: http://bit.ly/ytc-the-what-if-100-book.

Continue reading “Top What If Scenarios Recap” »

Nov 3, 2022

This Is What the Earth’s Magnetic Field Sounds Like! (Very Eerie) (4K)

Posted by in categories: particle physics, space

Does the Earth make a sound? Yes! and it’s very eerie!
The European Space Agency (ESA) recently released 5 minutes of haunting, crackling audio. Revealing what Earth’s magnetic field sounds like. Called the Magnetosphere, it is generated deep within the Earth’s interior, at its core. It extends out into space, creating a strong protective shield against things such as charged particles zipping out of the Sun, called the solar wind. And Without this powerful magnetic field, Earth would likely be a barren, cold, dry world. The audio clip you are about to experience might sound like the stuff of nightmares, but sit back, relax and listen to the strange creaking, crackling and rumbling of our planet’s protective shield. This is the sound of the Earth’s magnetic field.

Find out more about this audio clip — https://www.esa.int/Applications/Observing_the_Earth/FutureE…etic_field.

Continue reading “This Is What the Earth’s Magnetic Field Sounds Like! (Very Eerie) (4K)” »

Nov 2, 2022

Amazing photos from SpaceX’s Falcon Heavy USSF-44 mission

Posted by in category: space

SpaceX’s Falcon Heavy launched classified payloads for the U.S. Space Force on its fourth-ever mission on Nov. 1, 2022. Relive the highlights.

Nov 2, 2022

Cooling the Earth

Posted by in categories: climatology, engineering, policy, space, sustainability

Is solar geoengineering an alternative solution to the climate crisis?

Solar geoengineering is a branch of geoengineering that focuses on reflecting sunlight back into outer space to reduce global warming. There are several solar geoengineering techniques being researched; the most feasible one consists of spraying reflective aerosols in the stratosphere.

Continue reading “Cooling the Earth” »

Nov 1, 2022

Connecting Phases of the Strong Force

Posted by in categories: particle physics, quantum physics, space

Thermodynamic phases governed by the strong nuclear force have been linked together using multiple theoretical tools.

Quantum chromodynamics (QCD) is the theory of the strong nuclear force. On a fundamental level, it describes the dynamics of quarks and gluons. Like more familiar systems, such as water, a many-body system of quarks and gluons can exist in very different thermodynamic phases depending on the external conditions. Researchers have long sought to map the different corners of the corresponding phase diagram. New experimental probes of QCD—first and foremost the detection of gravitational waves from neutron-star mergers—allow for a more comprehensive view of this phase structure than was previously possible. Now Tuna Demircik at the Asia Pacific Center for Theoretical Physics, South Korea, and colleagues have put together models originally used in very different contexts to push forward a global understanding of the phases of QCD [1].

Phase transitions governed by the strong force require extreme conditions such as high temperatures and high baryon densities (baryons are three-quark particles such as protons and neutrons). The region of the QCD phase diagram corresponding to high temperatures and relatively low baryon densities can be probed by colliding heavy ions. By contrast, the region associated with high baryon densities and relatively low temperatures can be studied by observing single neutron stars. For a long time, researchers lacked experimental data for the phase space between these two regions, not least because it is very difficult to create matter under neutron-star conditions in the laboratory. This difficulty still exists, although collider facilities are being constructed that are intended to produce matter at higher baryon densities than is currently possible.

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