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Categories: Geoscience: Geomagnetic Storms, Space: Cosmology

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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.

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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.

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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.

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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.

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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.

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

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Researchers have observed the X-ray emission of the most luminous quasar seen in the last 9 billion years of cosmic history, known as SMSS J114447.77-430859.3, or J1144 for short. The new perspective sheds light on the inner workings of quasars and how they interact with their environment.

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Astronomers reveal the origin of a thermonuclear supernova explosion. Strong emission lines of helium and the first detection of such a supernova in radio waves show that the exploding white dwarf star had a helium-rich companion.

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Astronomers have uncovered the largest cosmic explosion ever witnessed. The explosion is more than ten times brighter than any known supernova and three times brighter than the brightest tidal disruption event, where a star falls into a supermassive black hole.

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Researchers have discovered a new generic production mechanism of gravitational waves generated by a phenomenon known as oscillons.

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Astronomers have found that supermassive black holes obscured by dust are more likely to grow and release tremendous amounts of energy when they are inside galaxies that are expected to collide with a neighbouring galaxy.

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Globular clusters are the most massive and oldest star clusters in the Universe. They can contain up to 1 million of them. The chemical composition of these stars, born at the same time, shows anomalies that are not found in any other population of stars. Explaining this specificity is one of the great challenges of astronomy. After having imagined that supermassive stars could be at the origin, a team believes it has discovered the first chemical trace attesting to their presence in globular proto-clusters, born about 440 million years after the Big Bang.

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A team used a first-of-its-kind technique to measure the expansion rate of the Universe, providing insight that could help more accurately determine the Universe's age and help physicists and astronomers better understand the cosmos.

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A 'beautiful effect' predicted by quantum electrodynamics (QED) can explain the puzzling first observations of polarized X-rays emitted by a magnetar -- a neutron star featuring a powerful magnetic field, according to an astrophysicist.

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Using ESO's Very Large Telescope (VLT), researchers have found for the first time the fingerprints left by the explosion of the first stars in the Universe. They detected three distant gas clouds whose chemical composition matches what we expect from the first stellar explosions. These findings bring us one step closer to understanding the nature of the first stars that formed after the Big Bang.

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A new study looked at a known binary star (two stars orbiting around a mutual center of gravity), analyzing starlight obtained from a range of ground- and space-based telescopes. The researchers found that the stars, located in a neighboring dwarf galaxy called the Small Magellanic Cloud, are in partial contact and swapping material with each other, with one star currently 'feeding' off the other. They orbit each other every three days and are the most massive touching stars (known as contact binaries) yet observed.

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Scientists have unlocked one of the biggest mysteries of quasars -- the brightest, most powerful objects in the Universe -- by discovering that they are ignited by galaxies colliding.

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Every giant was once a baby, though you may never have seen them at that stage of their development. NASA's James Webb Space Telescope has begun to shed light on formative years in the history of the universe that have thus far been beyond reach: the formation and assembly of galaxies. For the first time, a protocluster of seven galaxies has been confirmed at a distance that astronomers refer to as redshift 7.9, or a mere 650 million years after the big bang. Based on the data collected, astronomers calculated the nascent cluster's future development, finding that it will likely grow in size and mass to resemble the Coma Cluster, a monster of the modern universe.

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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.

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A star's chemical composition strongly influences the ultraviolet radiation it emits into space and thus the conditions for the emergence of life in its neighborhood.