Tag

Astrophysics

All articles tagged with #astrophysics

space3 days ago•10 min saved

Rare helium nova in our galaxy reveals unusual stellar fireworks

Astronomers have confirmed the galaxy’s first helium nova, V445 Puppis, a binary system where a white dwarf siphons material from a helium-star companion; after a dust-enshrouded outburst around 2000, the now-visible ejecta include oxygen-rich “bullets” racing through space at up to 20 million mph. Studying this rare explosion helps illuminate how such novae occur and could shed light on the origins of Type Ia supernovae, which are used as standard candles to gauge cosmic distances.

via The Independent|

#astronomers #astrophysics #helium-nova

space15 days ago•104 min saved

Cosmic ghost neutrinos whisper from ancient supernovae

Researchers analyzing 14 years of data from the Super-Kamiokande detector report a likely signal of the Diffuse Supernova Neutrino Background—the universe’s background of neutrinos from all past core-collapse supernovas—marking a potential first detection of these cosmic 'ghost' particles; if confirmed, it would illuminate how dying stars enrich their environments and form compact remnants, with plans to combine data with Hyper-Kamiokande to boost sensitivity.

via Space|

#astrophysics #diffuse-supernova-neutrino-background #neutrinos

space16 days ago•7 min saved

Silent Messengers: Neutrinos Illuminate Hidden Galactic Explosions

Avi Loeb explains that neutrinos from Galactic supernovae penetrate interstellar dust and reveal explosions that optical observations often miss. The 1987 SN 1987A produced 24 neutrinos detected by Kamiokande-II, IMB, and Baksan, enabling estimates of the explosion’s energy and the newborn neutron star’s properties. Today’s and forthcoming detectors—Super-Kamiokande, JUNO, IceCube, Hyper-Kamiokande, and DUNE—could observe thousands to tens of thousands of events from a Milky Way supernova, allowing measurements of neutrino masses and oscillations as well as the neutron star’s mass, radius, and binding energy. Webb’s 2022 observations of a neutron-star signature in SN 1987A underscore the potential of neutrino astronomy for probing fundamental physics and stellar remnants.

via Avi Loeb – Medium|

#astrophysics #detectors #neutrinos

science22 days ago•185 min saved

Rubin Observatory kicks off a decade-long cosmic survey

The Vera C. Rubin Observatory in Chile has begun the decade‑long Legacy Survey of Space and Time (LSST), using the world’s largest digital camera to capture nightly, color‑rich images of the southern sky and stitch them into a living map of celestial evolution. The project aims to inventory the solar system and Milky Way, investigate dark matter and dark energy, and enable billions of objects with trillions of measurements to be released publicly, generating about 7 million alerts per night for notable events such as asteroids and supernovae. Preliminary imagery began in 2025, and the survey will repeatedly re-image the same sky patches to track changes over time.

via CNN|

#astronomy #astrophysics #dark-matter

science-space24 days ago•3 min saved

Earth May Outlast the Sun’s Death, New Study Finds

A new study in Astronomy and Astrophysics suggests Earth could survive the Sun’s 5-billion-year demise, depending on whether tidal forces pull Earth inward or the Sun’s mass loss pushes Earth outward. Observations of the nearby dying star L2 Puppis inform these models, but the outcome remains uncertain and requires better data. Even if Earth endures, the Sun’s increasing heat will make the planet uninhabitable long before the final collapse, and humanity would not survive the event.

via New York Post|

#astronomy #astrophysics #earth

science1 month ago•10 min saved

Chasing Ghost Particles: The Global Quest to Catch Neutrinos

Physicists have built some of the world’s most ambitious detectors—buried underground, underwater, and under Antarctic ice—to catch neutrinos, elusive particles that rarely interact with matter. From Pauli’s proposal and the first detection in the 1950s to solar-neutrino puzzles and modern observatories like Kamiokande, Super-Kamiokande, SNO, IceCube, KM3NeT, JUNO, DUNE, and Hyper-K, the field has shown neutrinos come in flavors that oscillate due to mass, guiding experimental design and enabling study of stars, the cosmos, and fundamental physics.

via Quanta Magazine|

#astrophysics #neutrino-detectors #neutrino-oscillations

science1 month ago•96 min saved

Milky Way gamma-ray glow still leaves dark matter in contention

Using machine learning on more than a million simulated gamma-ray observations, researchers test whether the Galactic Center Excess—the Milky Way’s central gamma-ray glow—could come from self-annihilating dark matter or from many faint pulsars. They find pulsars would have to be far more numerous and dim than previously thought, making them hard to distinguish from a dark-matter signal, so dark matter remains a plausible but unproven explanation; the bright, crowded galactic center makes definitive conclusions difficult.

via Space|

#astrophysics #dark-matter #galactic-center

space1 month ago•7 min saved

Third Dark-Matter-Free Galaxy Emerges

Researchers identify NGC 1052-DF9 as the third galaxy whose motions can be explained without dark matter, suggesting it formed through a violent “bullet dwarf collision” that separates ordinary matter from dark matter and offers new clues about the nature of dark matter.

via ScienceAlert|

#astrophysics #bullet-dwarf-collision #dark-matter

technology1 month ago•1 min saved

Touch the Cosmos Without Leaving the Ground: Smithsonian's New VR Experience

A new 5,000-square-foot VR attraction in Washington, D.C., created by Fever with the Smithsonian Astrophysical Observatory, lets visitors explore the cosmos from the ground—standing in for the Sun’s surface, crossing the event horizon of a black hole, and viewing the Pillars of Creation—using data-driven visuals and scientist input to convey the vastness of space.

via WTOP|

#astrophysics #cosmos #immersive-experience

science1 month ago•4 min saved

The Sun’s Self-Regulating Thermostat: Fusion Keeps the Light On, Gravity Keeps It Going

Fusion barely powers the Sun; its gravity continuously compresses the core, heating it just enough to keep fusion in a self-regulating balance with hydrostatic equilibrium. If fusion stopped, the Kelvin-Helmholtz mechanism would let the Sun slowly shrink and release heat, keeping it shining far longer as a natural thermostat with no moving parts. The Sun actually heats up as it loses energy, and internal changes propagate extremely slowly. Part 3 will trace a photon’s 100,000-year journey out of the Sun.

via Universe Today|

#astrophysics #fusion #hydrostatic-equilibrium

science1 month ago•2 min saved

Tiny Universes May Spawn Inside Collapsing Stars, Study Suggests

Researchers propose that extremely collapsed stars could halt at a gravastar stage, with outward dark-energy pressure creating a stable, tiny universe inside rather than forming a traditional black hole; the idea preserves black holes as possible outcomes but adds an exotic alternative, published in Physical Review D.

via Futurism|

#astrophysics #black-holes #dark-energy

science1 month ago•3 min saved

Topology Reveals Global Shape of Black Hole Thermodynamics

Black holes are not just features of their accretion disks: they possess intrinsic temperature and entropy, and topology is used to classify their thermodynamic behavior. By identifying special zero points in the thermodynamic landscape and assigning them topological charges, physicists derive a global fingerprint that distinguishes different black-hole types (such as Schwarzschild vs. Reissner–Nordström) while remaining robust to changes in mass, charge, or spin; this approach links stability and state transitions to invariant properties and could illuminate paths toward quantum gravity, with implications for light rings and spacetime bending.

via Universe Today|

#astrophysics #black-holes #quantum-gravity

astronomy1 month ago•17 min saved

Cosmic scale: from kilometer-sized rocks to galaxy-sized grandeur

A broad tour of the cosmos’ size spectrum, from hydrostatic, kilometer-scale bodies like small moons and asteroids to white dwarfs, neutron stars, and black holes, then up through dwarf galaxies, huge galaxies, galaxy clusters, and the vast cosmic web. The article explains how gravity, hydrostatic equilibrium, and dark matter shape these objects, how light and gravitational lensing reveal their properties, and notes that while some structures seem enormous (e.g., the Sloan Great Wall, Train Wreck clusters), no larger bound structures have been confirmed. It emphasizes the universe’s staggering range of scales and complexities.

via Big Think|

#astronomy #astrophysics #black-holes

science1 month ago•4 min saved

Jupiter's Foreshock Reveals a Universal Particle Accelerator

New Juno data show electrons in Jupiter's foreshock gaining relativistic speeds, revealing a natural, large-scale accelerator that may unify how shock-driven particle acceleration works across the universe; the framework will be tested by upcoming missions like Europa Clipper and Juice.

via Gizmodo|

#astrophysics #jupiter #planetary-science

space1 month ago•52 min saved

Cosmic water giant around distant quasar reveals early-universe chemistry

Astronomers detected a giant reservoir of water around quasar APM 08279+5255, a supermassive black hole about 12 billion light-years away. The water vapor equals roughly 140 trillion times Earth’s oceans in volume, exists in hot, dense gas around the quasar (heated by intense infrared and X-ray radiation) and sits within a total gas reservoir of about 100 billion solar masses, with the water vapor itself weighing at least 25,000 solar masses. The surrounding gas is around −63°F (−52°C) and 10–100 times denser than typical galactic gas. This finding shows water was already widespread in the early universe and provides a new probe of black-hole influence on its environment; the study appears in Astrophysical Journal Letters.

via The Brighter Side of News|

#astrophysics #early-universe #quasar