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Artificial intelligence is more likely to save humanity than to destroy it, Jeff Bezos said recently. The billionaire also said he would like to see the human population grow to one trillion, with most people living in huge cylindrical space stations.

In an interview with podcaster Lex Fridman, the Amazon AMZN, +1.73% founder and former CEO rejected the idea that humans should colonize other planets, saying he believes building space colonies is the only way to achieve such population growth.

A NASA technology experiment on the International Space Station completed its first laser link with an in-orbit laser relay system on Dec. 5, 2023. Together, they complete NASA’s first two-way, end-to-end laser relay system.

NASA’s LCRD (Laser Communications Relay Demonstration) and the new space station demonstration, ILLUMA-T (Integrated LCRD Low Earth Orbit User Modem and Amplifier Terminal), successfully exchanged data for the first time. LCRD and ILLUMA-T are demonstrating how a user mission, in this case the space station, can benefit from a laser communications relay located in geosynchronous orbit.

HELSINKI — China sent the classified Yaogan-41 optical satellite towards the geostationary belt Friday using the country’s largest launch vehicle.

The sixth Long March 5 rocket lifted off from the coastal Wenchang Satellite Launch Center at 8:41 a.m. Eastern (1341 UTC) Dec. 15. The China Aerospace Science and Technology Corp. (CASC) announced launch success around an hour later.

CASC revealed the payload to be the Yaogan-41 (“remote sensing-41”) satellite. A new, elongated 18.5-meter-long, 5.2-meter-diameter payload fairing shrouded the spacecraft. Previous fairings were 12.3 meters long.

WASHINGTON — Rocket Lab successfully launched a Japanese radar imaging satellite on the first flight of its Electron rocket since a failure nearly three months ago.

The Electron rocket lifted off from the company’s Launch Complex 1 in New Zealand at 11:05 p.m. Eastern Dec. 14. The vehicle deployed its payload, the QPS-SAR-5 or Tsukuyomi-1 satellite for Japanese company iQPS, nearly 57 minutes after liftoff into a 575-kilometer orbit.

The launch was the first for Electron since a Sept. 19 failure during a launch of another radar imaging satellite for Capella Space. On that mission, the first stage performed as expected but the engine of the second stage appeared to shut down immediately after ignition, preventing it from reaching orbit.

Experiments verify a theory that explains why paint doesn’t dry any faster on a dry day than on a wet day.

You might think that polymer solutions like paint dry more slowly on a humid day than on a dry day. But researchers have now verified a theory that explains why the evaporation rate of the water or another solvent in a polymer solution can be independent of the ambient humidity [1]. The experiments show that, as predicted, water evaporation drives the polymer molecules toward the surface, where they form a dense layer that hinders evaporation and shields the surface from humidity effects. This phenomenon may affect the rate at which virus-containing respiratory droplets evaporate and thus could help explain the seasonal dependence of viral infections.

Humidity-independent evaporation is an advantage in many situations. For example, to preserve the body’s hydration, human skin maintains a nearly constant evaporation rate thanks to cell membranes whose lipid molecules can be reconfigured to adjust the sweat evaporation rate. This reconfiguration is an example of an active process. In 2017, Jean-Baptiste Salmon, a chemical engineer at the University of Bordeaux in France, proposed that humidity-independent evaporation does not require an active response [2]. Instead, his theory suggested that it occurs whenever the solvent evaporates from a solution of large molecules, a process that was already known to draw those molecules toward the drying interface. He predicted that, after the large molecules form a dense layer, the solvent’s evaporation rate will remain unchanged whether the surroundings are bone dry or at 100% humidity. However, the theory has not been tested with a nonactive polymer solution.

Researchers in China have produced a phenomenon known as the giant skyrmion topological Hall effect in a two-dimensional material using only a small amount of current to manipulate the skyrmions responsible for it. The finding, which a team at Huazhong University of Science and Technology in Hubei observed in a ferromagnetic crystal discovered in 2022, comes about thanks to an electronic spin interaction known to stabilize skyrmions. Since the effect was apparent at a wide range of temperatures, including room temperature, it could prove useful for developing two-dimensional topological and spintronic devices such as racetrack memory, logic gates and spin nano-oscillators.

Skyrmions are quasiparticles with a vortex-like structure, and they exist in many materials, notably magnetic thin films and multilayers. They are robust to external perturbations, and at just tens of nanometres across, they are much smaller than the magnetic domains used to encode data in today’s hard disks. That makes them ideal building blocks for future data storage technologies such as “racetrack” memories.

Skyrmions can generally be identified in a material by spotting unusual features (for example, abnormal resistivity) in the Hall effect, which occurs when electrons flow through a conductor in the presence of an applied magnetic field. The magnetic field exerts a sideways force on the electrons, leading to a voltage difference in the conductor that is proportional to the strength of the field. If the conductor has an internal magnetic field or magnetic spin texture, like a skyrmion does, this also affects the electrons. In these circumstances, the Hall effect is known as the skyrmion topological Hall effect (THE).

Each year at its annual meeting, the American Physical Society’s Division of Fluid Dynamics sponsors a contest for the best images in a variety of categories, all related to the flow of fluids.

This year’s Gallery was presented at the Division’s 76th meeting in November in Washington, D.C., with 12 artistic videos and images being selected in four different categories. Here are some of the winners.

Materials with enhanced thermal conductivity are critical for the development of advanced devices to support applications in communications, clean energy and aerospace. But in order to engineer materials with this property, scientists need to understand how phonons, or quantum units of the vibration of atoms, behave in a particular substance.

“Phonons are quite important for studying new because they govern several such as thermal conductivity and carrier properties,” said Fuyang Tay, a graduate student in applied physics working with the Rice Advanced Magnet with Broadband Optics (RAMBO), a tabletop spectrometer in Junichiro Kono’s laboratory at Rice University. “For example, it is widely accepted that superconductivity arises from electron–phonon interactions.

Recently, there has been growing interest in the carried by phonon modes that show circular motion, also known as chiral . But the mechanisms that can lead to a large phonon magnetic moment are not well understood.