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Categories: Space: Cosmology
Published Never-before-seen way to annihilate a star (via sciencedaily.com) Original source
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 Astronomers discover new link between dark matter and clumpiness of the universe (via sciencedaily.com) Original source
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 (via sciencedaily.com) Original source
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' (via sciencedaily.com) Original source
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 New study identifies mechanism driving the sun's fast wind (via sciencedaily.com) Original source
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 (via sciencedaily.com) Original source
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 (via sciencedaily.com) Original source
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 (via sciencedaily.com) Original source
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 (via sciencedaily.com) Original source
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 Astrophysicists confirm the faintest galaxy ever seen in the early universe (via sciencedaily.com) Original source
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 (via sciencedaily.com) Original source
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 (via sciencedaily.com) Original source
The latest observations from Low Earth Orbit with the International Space Station provide further evidence of spectral hardening and softening of cosmic ray particles.
Published An X-ray look at the heart of powerful quasars (via sciencedaily.com) Original source
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.
Published Radio signal reveals supernova origin (via sciencedaily.com) Original source
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.
Published Astronomers reveal the largest cosmic explosion ever seen (via sciencedaily.com) Original source
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.
Published Researchers find new approach to explore earliest universe dynamics with gravitational waves (via sciencedaily.com) Original source
Researchers have discovered a new generic production mechanism of gravitational waves generated by a phenomenon known as oscillons.
Published Hidden supermassive black holes brought to life by galaxies on collision course (via sciencedaily.com) Original source
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.
Published Celestial monsters at the origin of globular clusters (via sciencedaily.com) Original source
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.
Published Measurement of the Universe's expansion rate weighs in on a longstanding debate in physics and astronomy (via sciencedaily.com) Original source
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.
Published Neutron star's X-rays reveal 'photon metamorphosis' (via sciencedaily.com) Original source
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.