WEBVTT

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<v Speaker 1>Welcome to Bedtime Astronomy. Explore the wonders of the cosmos

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<v Speaker 1>with our soothing Bedtime Astronomy podcast. Each episode offers a

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<v Speaker 1>gentle journey through the stars, planets, and beyond, perfect for

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<v Speaker 1>unwinding after a long day. Let's travel through the mysteries

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<v Speaker 1>of the universe as you drift off into a peaceful

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<v Speaker 1>slumber under the night sky. Black holes inherit magnetic might

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<v Speaker 1>from stellar parents, simulations reveal. Four years, astronomers have pondered

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<v Speaker 1>the origins of the powerful magnetic fields observed around black holes.

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<v Speaker 1>These invisible behemoths formed by the collapse of massive stars

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<v Speaker 1>are known to possess immense magnetic forces that can twist

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<v Speaker 1>and accelerate surrounding matter. However, the exact mechanisms behind this

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<v Speaker 1>magnetism remained a mystery. New research utilizing powerful computer simulations

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<v Speaker 1>sheds light on this cosmic puzzle, suggesting that black holes

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<v Speaker 1>inherit their magnetic prowess from their stellar ancestors. The study,

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<v Speaker 1>published in the journal Nature, employed sophisticated simulations to recreate

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<v Speaker 1>the final moments of a massive star's life. As the

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<v Speaker 1>star nears its inevitable collapse, its core undergoes a dramatic transformation.

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<v Speaker 1>Nuclear fusion ceases and the star's immense gravity takes over,

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<v Speaker 1>crushing the core into an incredibly dense object known as

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<v Speaker 1>a neutron star. However, if the star is sufficiently massive,

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<v Speaker 1>the collapse doesn't stop there. The immense gravitational forces overpower

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<v Speaker 1>even the neutrons, leading to the formation of a singularity,

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<v Speaker 1>a point of infinite density and gravity shrouded by an

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<v Speaker 1>event horizon, the point of no return for matter and light.

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<v Speaker 1>This monstrous entity is what we call a black hole.

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<v Speaker 1>The simulations focused on a crucial aspect of this stellar

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<v Speaker 1>death throw, the fate of the star's magnetic field. Prior

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<v Speaker 1>to collapse. The star possesses a large scale magnetic field

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<v Speaker 1>generated by churning currents of electrically charged gas within its core.

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<v Speaker 1>The researchers meticulously track the behavior of this magnetic field

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<v Speaker 1>as the star imploded. Their findings were fascinating. Thessimulations revealed

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<v Speaker 1>that during the initial stages of collapse, the star's magnetic

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<v Speaker 1>field gets stretched and amplified by the powerful gravitational forces.

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<v Speaker 1>As the material hurdles inwards, the magnetic field lines become

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<v Speaker 1>tightly interwoven, akin to crumpling a sheet of paper. This process,

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<v Speaker 1>known as magnetic field amplification, results in a much stronger

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<v Speaker 1>magnetic field concentrated around the nascent black hole. However, not

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<v Speaker 1>all of the star's magnetic field gets sucked into the

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<v Speaker 1>black hole. The simulation showed that a significant portion of

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<v Speaker 1>the field lines get expelled outwards, forming a vast, large

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<v Speaker 1>scale structure encompassing the black hole. This expelled field is

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<v Speaker 1>responsible for some of the spectacular phenomena observed around black holes,

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<v Speaker 1>such as the powerful jets of matter ejected at near

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<v Speaker 1>light speed. The research team emphasizes the significance of these

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<v Speaker 1>findings by demonstrating that black holes inherit their magnetic fields

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<v Speaker 1>from their progenitor stars. They provide a crucial piece of

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<v Speaker 1>the puzzle regarding the behavior of these enigmatic objects. Understanding

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<v Speaker 1>how black holes interact with their surroundings, particularly the influence

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<v Speaker 1>of their magnetic fields, is essential for unraveling the mysteries

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<v Speaker 1>of accretion discs, jets, and the very nature of black

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<v Speaker 1>holes themselves. These simulations not only provide valuable insights into

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<v Speaker 1>the origin of black hole magnetism, but also paved the

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<v Speaker 1>way for further exploration the researchers believe that their model

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<v Speaker 1>can be refined to investigate the influence of factors like

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<v Speaker 1>the star's initial rotation rate on the final magnetic field

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<v Speaker 1>of the black hole. Additionally, by incorporating different stellar models,

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<v Speaker 1>they hope to explore the diversity of magnetic field configurations

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<v Speaker 1>and various black hole whole environments. The quest to understand

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<v Speaker 1>black holes continues, with simulations playing a vital role in

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<v Speaker 1>bridging the gap between theory and observation. This new research

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<v Speaker 1>revealing the stellar inheritance of black hole magnetism is a

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<v Speaker 1>significant step forward, offering a glimpse into the powerful and

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<v Speaker 1>complex nature of these cosmic giants. New DESI data sheds

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<v Speaker 1>light on gravity's pull in the universe. Gravity has played

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<v Speaker 1>a pivotal role in shaping our cosmos, transforming tiny differences

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<v Speaker 1>in matter distribution in the early universe into the sprawling

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<v Speaker 1>galaxy strands we observe today. A groundbreaking study utilizing data

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<v Speaker 1>from the Dark Energy Spectroscopic Instrument DESI, has traced the

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<v Speaker 1>evolution of cosmic structure over eleven bis million years, providing

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<v Speaker 1>the most precise test the date of gravity at vast scales.

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<v Speaker 1>The DESI instrument mounted a four meter telescope at Kitt

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<v Speaker 1>Peak National Observatory captures light from five thousand galaxies simultaneously.

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<v Speaker 1>This international collaboration involves over nine hundred researchers from seventy

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<v Speaker 1>institutions worldwide, managed by the Department of Energy's LORENS Berkeley

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<v Speaker 1>National Laboratory. Researchers found that gravity behaves as predicted by

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<v Speaker 1>Einstein's theory of general relativity, validating the leading model of

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<v Speaker 1>the universe and limiting possible theories of modified gravity. This

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<v Speaker 1>study directly tests theories and confirms general relativity's predictions at

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<v Speaker 1>cosmological scales. General relativity has been well tested at solar

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<v Speaker 1>system scale, but we needed to test its assumption at

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<v Speaker 1>larger scales, said Pauline z Rook, cosmologist at the French

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<v Speaker 1>National Center for Scientific Research. Studying galaxy formation rates. Lets

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<v Speaker 1>us directly test our theories, and so far we're aligning

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<v Speaker 1>with general relativity predictions. The study also provided new upper

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<v Speaker 1>limits on neutrino masses, narrowing the window for these fundamental particles.

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<v Speaker 1>Using nearly six million galaxies and quasars, DESI has made

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<v Speaker 1>the most precise overall measurement of structure growth surpassing previous efforts.

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<v Speaker 1>This analysis expands on desi's first year data, which created

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<v Speaker 1>the largest three D map of the universe and hinted

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<v Speaker 1>at evolving dark energy, but DESI Collaboration's results demonstrate a

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<v Speaker 1>tremendous new ability to probe modified gravity and improve constraints

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<v Speaker 1>on dark energy models. With four years of data, DESI

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<v Speaker 1>plans to collect roughly forty million galaxies and quasars, presenting

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<v Speaker 1>updated measurements of dark energy in the universe's expansion history.

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<v Speaker 1>In twenty twenty five, dark matter makes up a quarter

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<v Speaker 1>of the universe and dark energy makes up seventy percent,

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<v Speaker 1>and we don't really know what either one is, said

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<v Speaker 1>Mark mouse pH dot d student at Berkeley Lab. And

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<v Speaker 1>you see, Berkeley. The idea that we can take pictures

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<v Speaker 1>of the universe and tackle these big fundamental questions is

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<v Speaker 1>mind blowing. The DESI Collaboration is honored to conduct research

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<v Speaker 1>on Ialagum Duichi kit Peak, a mountain significant to the

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<v Speaker 1>Tahana Wautum nation. As DESI continues to explore the USSE,

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<v Speaker 1>its findings will refine our understanding of gravity dark energy

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<v Speaker 1>in the cosmos by tracing the Universe's evolution researchers gain

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<v Speaker 1>insight into gravity's role in shaping cosmic structure. Desi's results

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<v Speaker 1>have significant implications for our understanding of the universe, providing

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<v Speaker 1>a deeper understanding of gravity's influence on galaxy distributions and properties.

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<v Speaker 1>The studies findings also highlight the importance of continued research

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<v Speaker 1>into the universe's mysteries. As scientists continue to analyze DESI data,

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<v Speaker 1>new discoveries will shed light on the intricacies of the cosmos.

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<v Speaker 1>In conclusion, the new DESI data sheds light on gravity's

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<v Speaker 1>pull in the universe, providing unprecedented insights into cosmic structure

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<v Speaker 1>and evolution. As researchers continue to explore the universe, we

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<v Speaker 1>can expect even more exciting discoveries that refine our understanding

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<v Speaker 1>of the cosmos. Hot gas halo encircles the Milky Way.

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<v Speaker 1>The Milky Way, our galactic home, is enveloped in a vast,

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<v Speaker 1>fiery halo of hot gas. This gaseous reservoir, far surpassing

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<v Speaker 1>the galaxy stellar mass, is the primary fuel for star formation. However,

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<v Speaker 1>its tenuous nature has made it elusive to direct observation

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<v Speaker 1>and quantification. Decades ago, astronomers unveiled the existence of a

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<v Speaker 1>massive million degree kelvin gas sphere surrounding the galaxy, stretching

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<v Speaker 1>to a staggering seven hundred thousand light years. This extreme

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<v Speaker 1>temperature was attributed to the gas Lexy's gravitational pull, forcing

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<v Speaker 1>atoms into rapid orbits to resist being drawn inward. In

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<v Speaker 1>more recent times, even hotter gas reaching a scorching ten

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<v Speaker 1>million kelvin was detected through faint X ray emissions and

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<v Speaker 1>quasar absorption spectra. A team of researchers from the Raman

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<v Speaker 1>Research Institute it Pullup Cut in Ohio State University, has

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<v Speaker 1>proposed a model to illuminate the origin of this mysterious

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<v Speaker 1>heat source, detailed in two studies published in the Astrophysical Journal.

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<v Speaker 1>They posit that the X ray emitting gas originates from

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<v Speaker 1>a puffed up region around the Milky Ways, disc heated

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<v Speaker 1>by supernova explosions from massive stars. This turbulent gas, driven

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<v Speaker 1>by the immense energy released by these stellar explosions, is

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<v Speaker 1>either ejected into the surrounding medium or falls back onto

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<v Speaker 1>the disc, fueling a continuous cycle of starbirth and death. Concurrently,

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<v Speaker 1>the absorbing gas, enriched in alph elements, is likely a

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<v Speaker 1>byproduct of supernovae from runaway stars that have been ejected

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<v Speaker 1>from the galactic disc. B Stellar explosions release alf elements

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<v Speaker 1>such as sulfur, magnesium, and neon, which are then absorbed

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<v Speaker 1>by the hot gas, producing the observed shadow signals. By

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<v Speaker 1>delving deeper into these faint X ray signals and rigorously

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<v Speaker 1>testing their proposed models at various frequencies, scientists aim to

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<v Speaker 1>unravel the intricate dynamics of the Milky Way's gaseous environment.

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<v Speaker 1>This research holds the potential to revolutionize our understanding of

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<v Speaker 1>galactic evolution and the processes that shape the cosmos. To

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<v Speaker 1>dom Ba,