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New solar observations indicate that plasma waves are responsible for the Sun’s outer atmosphere having different abundances of chemical elements than the Sun’s other layers.

The solar corona is a halo of hot, tenuous plasma that surrounds the Sun out to large distances. It is visible during solar eclipses (Fig. 1) but is usually outshone by the glare of the Sun’s surface, or photosphere. The corona has different abundances of chemical elements than the rest of the Sun, and a longstanding question has been why this disparity exists. New solar measurements by Mariarita Murabito at the Italian National Institute of Astrophysics (INAF) and colleagues suggest that the difference is caused by plasma waves dragging easily ionized elements from the Sun’s lower atmosphere into the corona [1]. This finding could lead to a better understanding of the structure of stars.

The corona is of great interest to solar physicists, partly because it produces the solar wind—an outflow of hot gas from the Sun. The solar wind is most evident to us on Earth when its particles become trapped in Earth’s magnetic field and collide with our atmosphere, causing an aurora. An important problem in solar physics is to determine which coronal structures generate the solar wind and how solar conditions affect the outflow’s properties. The elemental composition of the solar wind sheds light on its origins, as this composition does not change once the gas leaves the Sun. The solar wind can be directly sampled by spacecraft in situ, and its elemental abundances can be compared to coronal abundances inferred from spectroscopy.

In recent years, global environmental concerns have prompted a shift toward eco-friendly manufacturing in the field of organic synthetic chemistry. In this regard, research into photoredox catalytic reactions, which use light to initiate redox or reduction-oxidation reactions via a photoredox catalyst, has gained significant attention. This approach reduces the reliance on harsh and toxic reagents and uses visible light, a clean energy source.

In a new publication in Physical Review Letters, researchers in Amsterdam demonstrate a way to describe spin-boson systems and use this to efficiently configure in a desired state.

Quantum devices use the quirky behavior of quantum particles to perform tasks that go beyond what “classical” machines can do, including quantum computing, simulation, sensing, communication and metrology. These devices can take many forms, such as a collection of superconducting circuits, or a lattice of atoms or ions held in place by lasers or electric fields.

Regardless of their physical realization, quantum devices are typically described in simplified terms as a collection of interacting two-level or spins. However, these spins also interact with other things in their surroundings, such as light in superconducting circuits or oscillations in the lattice of atoms or ions. Particles of light (photons) and vibrational modes of a lattice (phonons) are examples of bosons.

A study now published in Nature Communications brings remarkable insights into the enigmatic behavior of supercritical fluids, a hybrid state of matter occupying a unique space between liquids and gases, and arising in domains that go from the pharmaceutical industry to planetary science. The obtained results are at the limit of current experimental possibilities and could only be obtained in a high flux neutron source such as the Institut Laue-Langevin (ILL).

Both literally and figuratively, light pervades the world. It banishes darkness, conveys telecommunications signals between continents and makes visible the invisible, from faraway galaxies to the smallest bacterium. Light can also help heat the plasma within ring-shaped devices known as tokamaks as scientists worldwide strive to harness the fusion process to generate green electricity.

A new study reveals the sun’s magnetic field originates closer to the surface, solving a 400-year-old mystery first probed by Galileo and enhancing solar storm forecasting.

An international team of researchers, including Northwestern University engineers, is getting closer to solving a 400-year-old solar mystery that stumped even famed astronomer Galileo Galilei.

Since first observing the sun’s magnetic activity, astronomers have struggled to pinpoint where the process originates. Now, after running a series of complex calculations on a NASA supercomputer, the researchers discovered the magnetic field is generated about 20,000 miles below the sun’s surface.

Researchers used dendrochronology and a radiocarbon spike from 5,259 BC to date a prehistoric Greek settlement to over 7,000 years ago. This new method enables precise dating for other Southeast European archaeological sites.

Researchers at the University of Bern have, for the first time, precisely dated a prehistoric settlement of early farmers in northern Greece to over 7,000 years ago. They achieved this by combining annual growth ring measurements on wooden building elements with a significant spike in cosmogenic radiocarbon dating to 5,259 BC. This method provides a reliable chronological reference point for numerous other archaeological sites in Southeast Europe.

Dating finds plays a key role in archaeology. It is always essential to find out how old a tomb, settlement, or single object is. Determining the age of finds from prehistoric times has only been possible for a few decades. Two methods are used for this: dendrochronology, which enables dating on the basis of sequences of annual rings in trees, and radiocarbon dating, which can calculate the approximate age of the finds by the decay rate of the radioactive carbon isotope 14 C contained in the tree rings.