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Truly chiral phonons observed in three-dimensional materials for the first time

Chirality is the breaking of reflection and inversion symmetries. Simply put, it is when an object’s mirror images cannot be superimposed over each other. A common example are your two hands—while mirror images of each other, they can never overlap. Chirality appears at all levels in nature and is ubiquitous.

In addition to static , chirality can also occur due to dynamic motion including rotation. With this in mind, we can distinguish true and false chirality. A system is truly chiral if—when translating—space inversion does not equate to time reversal combined with a proper spatial rotation.

Phonons are quanta (or small packets) of energy associated with the vibration of atoms in a . Recently, phonons with chiral properties have been theorized and experimentally discovered in two-dimensional (2D) materials such as tungsten diselenide. The discovered chiral phonons are rotating—yet not propagating—atomic motions. But, truly chiral phonons would be atomic motions that are both rotating and propagating, and these have never been observed in three-dimensional (3D) bulk systems.

Astronauts Command Robotic Arm to Capture Cygnus

At 5:20 a.m. EST, NASA astronaut Nicole Mann, with NASA astronaut Josh Cassada acting as backup, captured Northrop Grumman’s Cygnus spacecraft using the International Space Station’s Canadarm2 robotic arm. Mission control in Houston will actively command the arm to rotate Cygnus to its installation orientation and then to guide it in for installation on the station’s Unity module Earth-facing port.

NASA Television, the NASA app, and agency’s website will provide live coverage of the spacecraft’s installation beginning at 7:15 a.m.

The Cygnus spacecraft launched Monday on an Antares rocket from NASA’s Wallops Flight Facility, Virginia at 5:32 a.m. This is Northrop Grumman’s 18th commercial resupply mission to the International Space Station for NASA. The Cygnus spacecraft is carrying a supply of 8,200 pounds of scientific investigations and cargo to the orbiting laboratory.

Wireless power from space

Solar power gathered far away in space, seen here being transmitted wirelessly down to Earth to wherever it is needed. ESA plans to investigate key technologies needed to make Space-Based Solar Power a working reality through its SOLARIS initative. One such technology – wireless power transmission – was recently demonstrated in Germany to an audience of decision makers from business and government.

The demonstration took place at Airbus’ X-Works Innovation Factory in Munich. Using microwave beaming, green energy was transmitted green energy between two points representing ‘Space’ and ‘Earth’ over a distance of 36 metres.

The received power was used to light up a model city, produce green hydrogen by splitting water and even to produce the world’s first wirelessly cooled 0% alcohol beer in a fridge before serving to the watching audience.

Making Suns

Use my link http://www.audible.com/isaac or text “ISAAC” to 500–500 to get a free book including a copy of Olaf Stapledon’s “Star Maker“
Without the Sun our world would be a frozen wasteland, and for this reason any efforts to colonize the galaxy must focus on huddling in the tiny oases of warmth around stars, separated from each other by enormous gulfs of interstellar space. But what if we could make our own stars at the places of our choosing? And can we merely mimic nature or create stars unlike anything which nature has formed?

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Credits:
Making Suns.
Episode 168, Season 5 E02

Written by.

Dr. James Revill, Ph.D. — Head of Weapons of Mass Destruction & Space Security Programs, UNIDIR

Building A More Secure World — Dr. James Revill, Ph.D. — Head of Weapons of Mass Destruction & Space Security Programs, UNIDIR, UN Institute for Disarmament Research United Nations.


Dr. James Revill, Ph.D. (https://unidir.org/staff/james-revill) is the Head of the Weapons of Mass Destruction (WMD) and Space Security Program, at the UN Institute for Disarmament Research (UNIDIR).

Dr. Revill’s research interests focus on the evolution of the chemical and biological weapons and he has published widely in these areas. He was previously a Research Fellow with the Harvard Sussex Program at the Science Policy Research Unit, University of Sussex and completed research fellowships with the Landau Network Volta Center in Italy and the Bradford Disarmament Research Centre in the UK.

Dr. Revill holds a Ph.D. focused on the evolution of the Biological Weapons Convention from the University of Bradford, UK.

Dr. Revill’s areas of expertise include biological weapons, biosecurity, bioterrorism, chemical weapons, chemical terrorism, chemical weapons convention, compliance, verification, and improvised explosive devices.

Inside NASA’s most mind-blowing Mars base designs — including inflatable homes

THE most impressive designs for near-future Mars bases have finally been revealed.

These elaborate celestial plans are the difference between human life surviving on Mars – and thriving.

When it comes to planning how to live on a planet like Mars, 3D printing has provided scientists with the easiest way of navigating an environment that has similarities, but ultimately boasts a vastly different environment from Earth.

Solar cells one-thousandth the size of human hair can resist space radiation

Earth’s low orbit is filling up, meaning radiation-tolerant cell designs are required as satellites head to higher orbits. Will these new ones do?

Scientists have developed a radiation-tolerant photovoltaic cell design that features an ultrathin layer of light-absorbing material. According to a new study published today (Nov .08) in the Journal of Applied Physics by AIP Publishing.

Significantly, the ultra-thin solar cells not only surpass earlier suggested thicker solar cells in resilience to irradiation; they also produce the same amount of power from converted sunlight after 20 years of use. Additionally, the novel photovoltaic cells could reduce load and considerably lower launch expenses. Barthel.

In a world first, astronomers observed a star with a solid outer surface

“This was completely unexpected.”

Stars are essentially large fiery balls of plasma, which is often referred to as the “fourth state of matter” as it forms when gas is heated into a soup of positively charged ions and negatively charged electrons.

The star’s magnetic field is so strong it appears to have “frozen” its surface into a solid outer crust, a press statement reveals.


Naeblys/iStock.

Now, though, an international group of astronomers has observed a star with a solid outer layer for the first time, casting doubt on widely held preconceptions about the cosmic giants lighting the night sky.