エピソード

  • SPHEREx Maps the Entire Sky in 3D Infrared

    SPHEREx Maps the Entire Sky in 3D Infrared
    2025/12/23
    NASA's SPHEREx telescope has created the first complete 3D infrared sky map using 102 wavelengths invisible to human eyes. This revolutionary dataset tracks galaxy evolution and the chemical building blocks of life across hundreds of millions of celestial objects.

    Unlike telescopes studying narrow fields, SPHEREx scans the entire cosmos every six months, measuring distances through spectroscopy to reveal how the universe expanded after the Big Bang.

    The freely available data helps scientists understand how our universe became habitable, with multiple scans planned over two years to enhance observation quality.
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    38 分
  • Superkilonova: The Dual Cosmic Explosion

    Superkilonova: The Dual Cosmic Explosion
    2025/12/21
    A baffling cosmic event, designated AT2025ulz, was detected by LIGO and Virgo and is now considered a candidate for a never-before-seen phenomenon: a superkilonova. This oddball event, which took place 1.3 billion light-years away, initially resembled a kilonova—an explosion caused by the merger of two dense neutron stars. Kilonovae are known to forge the heaviest elements, such as gold and uranium.

    However, after about three days, AT2025ulz started to look more like a supernova, brightening, turning blue, and showing hydrogen in its spectra. The gravitational-wave data indicated that at least one of the colliding objects was less massive than a typical neutron star.

    Astronomers hypothesize that this "superkilonova" was a kilonova spurred by a prior supernova blast. The leading theory suggests that a rapidly spinning, massive star went supernova, birthing two "forbidden" sub-solar mass neutron stars. These newborn stars may have then spiraled together and merged, creating a kilonova. This scenario would explain why the event displayed features of both a supernova and a kilonova, potentially obscuring the initial merger. This potential cosmic rarity challenges our understanding of stellar death and the formation of heavy elements.
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    33 分
  • Mapping the Magellanic Clouds: The 1001MC Stellar Survey

    Mapping the Magellanic Clouds: The 1001MC Stellar Survey
    2025/12/19
    This episode explores a new five-year astronomical survey of the Large and Small Magellanic Clouds using the 4MOST spectrograph on the VISTA Telescope.

    Led by the Leibniz Institute for Astrophysics Potsdam, the 1001MC project will collect high-resolution spectra from nearly 500,000 stars to reveal their motions, chemical composition, and history.

    We discuss how this data could answer long-standing questions about the formation and evolution of these dwarf galaxies, with full operations starting in 2026.
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    32 分
  • James Webb Reveals a Hidden Supermassive Black Hole in the Early Universe

    James Webb Reveals a Hidden Supermassive Black Hole in the Early Universe
    2025/12/17
    New James Webb Space Telescope observations reveal that a seemingly ordinary young galaxy, seen just 800 million years after the Big Bang, hides a rapidly growing, dust-enshrouded supermassive black hole.

    Infrared data from JWST’s MIRI instrument challenge established models of black hole and galaxy co-evolution and suggest that many similar objects may remain undetected across the universe.
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    30 分
  • Record-Breaking Gamma-Ray Burst Near Light Speed

    Record-Breaking Gamma-Ray Burst Near Light Speed
    2025/12/15
    Discover the fastest cosmic explosion ever recorded! We explore GRB 230307A, a gamma-ray burst detected by NASA's Fermi Space Telescope that reached 99.99998% of light speed—a breakthrough led by University of Alabama graduate researchers.

    Learn how this ultrarelativistic jet from a neutron star merger revealed an associated kilonova, offering new insights into how heavy elements like tellurium form in our universe.

    This episode highlights cutting-edge space science and the crucial role of student researchers in unlocking cosmic mysteries. Key topics: gamma-ray bursts, neutron star mergers, kilonova, heavy element formation, relativistic physics
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    22 分
  • New Maps Reveal a Wetter Red Planet

    New Maps Reveal a Wetter Red Planet
    2025/12/13
    Mars wasn't always the barren desert we see today. New research has mapped sixteen massive ancient river systems across the red planet for the first time—and the scale is staggering.

    Scientists at the University of Texas at Austin used orbital laser data to trace drainage basins that once carried enormous volumes of water across Mars's surface. These ancient watersheds produced roughly 28,000 cubic kilometers of sediment—evidence of rivers that flowed for potentially millions of years.

    But here's the mystery: where did all that water go? Mars was once warm and wet enough to sustain vast river networks, yet today it's a frozen wasteland with an atmosphere 100 times thinner than Earth's.

    In this episode, we explore what these newly mapped river systems tell us about Mars's vanished oceans, the catastrophic loss of its magnetic field that stripped away its atmosphere, and the climate collapse that transformed a potentially habitable world into the desolate planet we see today.

    The maps also raise tantalizing questions: if Mars had this much flowing water, could it have harbored life? And what can this planetary death teach us about Earth's own fragile climate?

    The red planet's rivers are long gone—but their ghosts remain, etched into the landscape, waiting to tell their story.
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    37 分
  • How 2025 Interferometry Revealed Stellar Complexity

    How 2025 Interferometry Revealed Stellar Complexity
    2025/12/11
    New interferometry observations from the CHARA Array have captured unprecedented real-time images of stellar nova explosions, revealing they're far more complex than scientists thought. These 2025 findings show multiple interacting material outflows instead of simple bursts—one nova displayed perpendicular gas flows, while another exhibited a dramatic 50-day ejection delay.

    By linking these high-resolution structures with Fermi telescope gamma-ray data, researchers can now explain how powerful shock waves form during these events. This breakthrough transforms our understanding of novae from basic explosions into dynamic, varied cosmic laboratories.
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    26 分
  • Ultra-Relativistic Dark Matter: Reviving a 50-Year-Old Theory

    Ultra-Relativistic Dark Matter: Reviving a 50-Year-Old Theory
    2025/12/09
    Physicists Stephen Henrich and Keith Olive are breathing new life into a dark matter theory abandoned in the 1970s. Their "ultra-relativistic freeze-out" mechanism proposes that dark matter separated from ordinary matter much earlier than previously thought—during the reheating era right after cosmic inflation.

    The original hot dark matter concept was rejected because fast-moving particles would have disrupted early galaxy formation. By moving this freeze-out event earlier in cosmic history, the particles would have had time to cool down, making them compatible with what we observe today.

    This approach helps explain why decades of detection experiments have come up empty. Ultra-relativistic dark matter interacts even more weakly than WIMP candidates, sitting between WIMPs and FIMPs as a long-overlooked category that could finally solve the universe's missing mass mystery.
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    28 分