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Categories: Geoscience: Volcanoes, Space: Cosmology
Published Climate change will increase impacts of volcanic eruptions



Volcanic disasters have been studied since Pompeii was buried in 79 A.D., leading the public to believe that scientists already know why, where, when and how long volcanoes will erupt. But a volcanologist said these fundamental questions remain a mystery.
Published Starlight and the first black holes: researchers detect the host galaxies of quasars in the early universe



For the first time, the James Webb Space Telescope has revealed starlight from two massive galaxies hosting actively growing black holes -- quasars -- seen less than a billion years after the Big Bang.
Published Effect of volcanic eruptions significantly underestimated in climate projections



Researchers have found that the cooling effect that volcanic eruptions have on Earth's surface temperature is likely underestimated by a factor of two, and potentially as much as a factor of four, in standard climate projections.
Published Einstein and Euler put to the test at the edge of the Universe



The cosmos is a unique laboratory for testing the laws of physics, in particular those of Euler and Einstein. Euler described the movements of celestial objects, while Einstein described the way in which celestial objects distort the Universe. Since the discovery of dark matter and the acceleration of the Universe's expansion, the validity of their equations has been put to the test: are they capable of explaining these mysterious phenomena? A team has developed the first method to find out. It considers a never-before-used measure: time distortion.
Published Never-before-seen way to annihilate a star



Astronomers studying a powerful gamma-ray burst, may have detected a never-before-seen way to destroy a star. Unlike most GRBs, which are caused by exploding massive stars or the chance mergers of neutron stars, astronomers have concluded that this GRB came instead from the collision of stars or stellar remnants in the jam-packed environment surrounding a supermassive black hole at the core of an ancient galaxy.
Published A Tongan volcano plume produced the most intense lightning rates ever detected



New research showed that the plume emitted by the Hunga Volcano eruption in 2022 created the highest lightning flash rates ever recorded on Earth, more than any storm ever documented.
Published Astronomers discover new link between dark matter and clumpiness of the universe



Researchers reveal a theoretical breakthrough that may explain both the nature of invisible dark matter and the large-scale structure of the universe known as the cosmic web. The result establishes a new link between these two longstanding problems in astronomy, opening new possibilities for understanding the cosmos. The research suggests that the 'clumpiness problem,' which centres on the unexpectedly even distribution of matter on large scales throughout the cosmos, may be a sign that dark matter is composed of hypothetical, ultra-light particles called axions. The implications of proving the existence of hard-to-detect axions extend beyond understanding dark matter and could address fundamental questions about the nature of the universe itself.
Published DESI early data release holds nearly two million objects



The first batch of data from the Dark Energy Spectroscopic Instrument is now available for researchers to explore. Taken during the experiment's 'survey validation' phase, the data include distant galaxies and quasars as well as stars in our own Milky Way.
Published Astronomers discover supernova explosion through rare 'cosmic magnifying glasses'



An international team of scientists recently discovered an exceptionally rare gravitationally lensed supernova, which the team named 'SN Zwicky.' Located more than 4 billion light years away, the supernova was magnified nearly 25 times by a foreground galaxy acting as a lens. The discovery presents a unique opportunity for astronomers to learn more about the inner cores of galaxies, dark matter and the mechanics behind universe expansion.
Published Campi Flegrei volcano edges closer to possible eruption



The new study used a model of volcano fracturing to interpret patterns of earthquakes and ground uplift, and concluded that parts of the volcano had been stretched nearly to breaking point.
Published South Africa, India and Australia shared similar volcanic activity 3.5 billion years ago



The Daitari greenstone belt shares a similar geologic make-up when compared to the greenstones exposed in the Barberton and Nondweni areas of South Africa and those from the Pilbara Craton of north-western Australia.
Published New study identifies mechanism driving the sun's fast wind



Researchers used data from NASA's Parker Solar Probe to explain how the solar wind is capable of surpassing speeds of 1 million miles per hour. They discovered that the energy released from the magnetic field near the sun's surface is powerful enough to drive the fast solar wind, which is made up of ionized particles -- called plasma -- that flow outward from the sun.
Published Webb Space Telescope detects universe's most distant complex organic molecules



Researchers have detected complex organic molecules in a galaxy more than 12 billion light-years away from Earth -- the most distant galaxy in which these molecules are now known to exist. Thanks to the capabilities of the recently launched James Webb Space Telescope and careful analyses from the research team, a new study lends critical insight into the complex chemical interactions that occur in the first galaxies in the early universe.
Published Early universe crackled with bursts of star formation, Webb shows



Among the most fundamental questions in astronomy is: How did the first stars and galaxies form? NASA's James Webb Space Telescope is already providing new insights into this question. One of the largest programs in Webb's first year of science is the JWST Advanced Deep Extragalactic Survey, or JADES, which will devote about 32 days of telescope time to uncover and characterize faint, distant galaxies. While the data is still coming in, JADES already has discovered hundreds of galaxies that existed when the universe was less than 600 million years old. The team also has identified galaxies sparkling with a multitude of young, hot stars.
Published Weigh a quasar's galaxy with precision



Scientists have managed to weigh -- more precisely than any other technique -- a galaxy hosting a quasar, thanks to the fact that it acts as a gravitational lens. Detection of strong gravitational lensing quasars is expected to multiply with the launch of Euclid this summer.
Published Eventually everything will evaporate, not only black holes



New theoretical research has shown that Stephen Hawking was likely right about black holes, although not completely. Due to Hawking radiation, black holes will eventually evaporate, but the event horizon is not as crucial as had been believed. Gravity and the curvature of spacetime cause this radiation too. This means that all large objects in the universe, like the remnants of stars, will eventually evaporate.
Published Petit-spot volcanoes involve the deepest known submarine hydrothermal activity, possibly release CO2 and methane



Underwater volcanism and its hydrothermal activity play an important role in marine biogeochemical cycles, especially the carbon cycle. But the nature of hydrothermal activity at 'petit-spot' volcanoes have not been revealed at all. Now, scientists reveal that petit-spot hydrothermal activity occurs on the deepest seafloor known to date and could release carbon dioxide (CO2) and methane, which may have implications for the global carbon cycle.
Published Astrophysicists confirm the faintest galaxy ever seen in the early universe



After the Big Bang, the universe expanded and cooled sufficiently for hydrogen atoms to form. In the absence of light from the first stars and galaxies, the universe entered a period known as the cosmic dark ages. The first stars and galaxies appeared several hundred million years later and began burning away the hydrogen fog left over from the Big Bang, rendering the universe transparent, like it is today. Researchers have now confirmed the existence of a distant, faint galaxy typical of those whose light burned through the hydrogen atoms; the finding should help them understand how the cosmic dark ages ended.
Published X-ray emissions from black hole jets vary unexpectedly, challenging leading model of particle acceleration



Black hole jets are known to emit x-rays, but how they accelerate particles to this high-energy state is still a mystery. Surprising new findings appear to rule out a leading theory, opening the door to reimagining how particle acceleration works. One model of how jets generate x-rays expects the jets' x-ray emissions to remain stable over long time scales. However, the new paper found that the x-ray emissions of a statistically significant number of jets varied over just a few years.
Published Helium nuclei research advances our understanding of cosmic ray origin and propagation



The latest observations from Low Earth Orbit with the International Space Station provide further evidence of spectral hardening and softening of cosmic ray particles.