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Categories: Energy: Alternative Fuels, Space: The Solar System
Published How 1,000 undergraduates helped solve an enduring mystery about the sun



For three years at the height of the COVID-19 pandemic, a group of students spent an estimated 56,000 hours analyzing the behavior of hundreds of solar flares. Their results could help astrophysicists understand how the sun's corona reaches temperatures of millions of degrees Fahrenheit.
Published Webb looks for Fomalhaut's asteroid belt and finds much more



Astronomers used NASA's James Webb Space Telescope to image the warm dust around a nearby young star, Fomalhaut, in order to study the first asteroid belt ever seen outside of our solar system in infrared light. But to their surprise, the dusty structures are much more complex than the asteroid and Kuiper dust belts of our solar system. Overall, there are three nested belts extending out to 14 billion miles (23 billion kilometers) from the star; that's 150 times the distance of Earth from the Sun. The scale of the outermost belt is roughly twice the scale of our solar system's Kuiper Belt of small bodies and cold dust beyond Neptune. The inner belts -- which had never been seen before -- were revealed by Webb for the first time.
Published Exciton fission: One photon in, two electrons out



Photovoltaics, the conversion of light to electricity, is a key technology for sustainable energy. Since the days of Max Planck and Albert Einstein, we know that light as well as electricity are quantized, meaning they come in tiny packets called photons and electrons. In a solar cell, the energy of a single photon is transferred to a single electron of the material, but no more than one. Only a few molecular materials like pentacene are an exception, where one photon is converted to two electrons instead. This excitation doubling, which is called exciton fission, could be extremely useful for high-efficiency photovoltaics, specifically to upgrade the dominant technology based on silicon. Researchers have now deciphered the first step of this process by recording an ultrafast movie of the photon-to-electricity conversion process, resolving a decades-old debate about the mechanism of the process.
Published Researchers develop an additive to efficiently improve the efficiency and stability of perovskite solar cells



Perovskite solar cells (PVSCs) are a promising alternative to traditional silicon-based solar cells because of their high power-conversion efficiency and low cost. However, one of the major challenges in their development has been achieving long-term stability. Recently, a research team made a breakthrough by developing an innovative multifunctional and non-volatile additive which can improve the efficiency and stability of perovskite solar cells by modulating perovskite film growth. This simple and effective strategy has great potential for facilitating the commercialization of PVSCs.
Published Hubble follows shadow play around planet-forming disk



The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. In 2017, astronomers reported discovering a shadow sweeping across the face of a vast pancake-shaped gas-and-dust disk surrounding the red dwarf star. The shadow isn't from a planet, but from an inner disk slightly inclined relative to the much larger outer disk -- causing it to cast a shadow. One explanation is that an unseen planet's gravity is pulling dust and gas into the planet's inclined orbit. The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. Now, a second shadow -- playing a game of peek-a-boo -- has emerged in just a few years between observations stored in Hubble's MAST archive. This could be from yet another disk nestled inside the system. The two disks are likely evidence of a pair of planets under construction.
Published Do your homework to prep for the 2023 and 2024 eclipses



This year and next, Americans will have the extraordinary opportunity to witness two solar eclipses as both will be visible throughout the continental U.S. Both occurrences promise to be remarkable events and teachable moments but preparation is essential. Astronomers provide a practical playbook to help teachers, students, and the general public prepare for the eclipse events.
Published Astronomers spot a star swallowing a planet



Scientists have observed a star swallowing a planet for the first time. Earth will meet a similar fate in 5 billion years.
Published What would the Earth look like to an alien civilization located light years away?



What would the Earth look like to an alien civilization located light years away? A team of researchers has used crowd-sourced data to simulate radio leakage from mobile towers and predict what an alien civilization might detect from various nearby stars, including Barnard's star, six light years away from Earth.
Published A stormy, active sun may have kickstarted life on Earth



The first building blocks of life on Earth may have formed thanks to eruptions from our Sun, a new study finds. A series of chemical experiments show how solar particles, colliding with gases in Earth's early atmosphere, can form amino acids and carboxylic acids, the basic building blocks of proteins and organic life.
Published Superflare with massive, high-velocity prominence eruption



A team of Japanese astronomers used simultaneous ground-based and space-based observations to capture a more complete picture of a superflare on a star. The observed flare started with a very massive, high-velocity prominence eruption. These results give us a better idea of how superflares and stellar prominence eruptions occur.
Published New findings indicate gene-edited rice might survive in Martian soil



New research suggests future Martian botanists may be able to grow gene-edited rice on Mars.
Published New chemistry can extract virgin-grade materials from wind turbine blades in one process



Researchers have developed a chemical process that can disassemble the epoxy composite of wind turbine blades and simultaneously extract intact glass fibers as well as one of the epoxy resin's original building blocks in a high quality. The recovered materials could potentially be used in the production of new blades.
Published Asteroid's comet-like tail Is not made of dust, solar observatories reveal



We have known for a while that asteroid 3200 Phaethon acts like a comet. It brightens and forms a tail when it's near the Sun, and it is the source of the annual Geminid meteor shower, even though comets are responsible for most meteor showers. Scientists had blamed Phaethon's comet-like behavior on dust escaping from the asteroid as it's scorched by the Sun. However, a new study using two NASA solar observatories reveals that Phaethon's tail is not dusty at all but is actually made of sodium gas.
Published How to land on a planet safely



Researchers develop a model to describe the interaction between a rocket plume and the surface of a planetary body in near-vacuum conditions. The computational framework takes in information about the rocket, its engines, and the surface composition and topography, as well as the atmospheric conditions and gravitational forces at the landing site, and the results can be used to evaluate the safety and feasibility of a proposed landing site and to optimize the design of spacecraft and rocket engines for planetary landings.
Published Scientists detect seismic waves traveling through Martian core



New NASA InSight research reveals that Mars has a liquid core rich in sulfur and oxygen, leading to new clues about how terrestrial planets form, evolve and potentially sustain life.
Published Pioneering research sheds new light on the origins and composition of planet Mars



A new study has uncovered intriguing insights into the liquid core at the centre of Mars, furthering understanding of the planet's formation and evolution.
Published Outstanding performance of organic solar cell using tin oxide



Organic solar cells have a photoactive layer that is made from polymers and small molecules. The cells are very thin, can be flexible, and are easy to make. However, the efficiency of these cells is still much below that of conventional silicon-based ones. Applied physicists have now fabricated an organic solar cell with an efficiency of over 17 percent, which is in the top range for this type of material. It has the advantage of using an unusual device structure that is produced using a scalable technique.
Published It's not as difficult as you think to shout upwind



Why does it feel so difficult to shout upwind? The sensation is common enough to have found its way into an idiom about not being understood. Researchers wanted a scientific explanation for the phenomenon -- and there wasn't been one. They have now shown that our common sense understanding of this situation is wrong. It isn't harder to shout into the wind; it's just harder to hear yourself.
Published Transforming highways for high-speed travel and energy transport



Researchers developed a proof of concept for a superconducting highway that could transport vehicles and electricity, cooling the necessary superconductors with a pipeline of liquid hydrogen. Most magnetic levitation designs feature the superconductor inside the vehicle, which is suspended above a magnetic track. The authors decided to flip that arrangement upside down, putting the superconductor on the ground and giving each vehicle a magnet. The result is a system with multiple uses, placing it within the realm of affordability.
Published Making better measurements of the composition of galaxies



A study using data from telescopes on Earth and in the sky resolves a problem plaguing astronomers working in the infrared and could help make better observations of the composition of the universe with the James Webb Space Telescope and other instruments.