Tag

Galaxy Clusters

All articles tagged with #galaxy clusters

science13 days ago•157 min saved

Two Million X-ray Sources Reveal New High-Energy Cosmos

Astronomers’ second public data release from the German-led eROSITA X-ray telescope, DR2, catalogs nearly 2 million X-ray sources—over 1.9 million point-like objects (mostly active supermassive black holes and Milky Way stars) and about 64,000 extended sources (galaxy clusters and remnants). By linking X-ray detections to optical/IR counterparts, DR2 provides the most comprehensive, uniform view of the high-energy universe to date, enabling robust studies of black-hole growth, galaxy evolution, and large-scale cosmic structures; a future DR3 is planned for 2028, effectively nearly doubling our view of the high-energy cosmos.

via Space|

#black-holes #dr2-catalog #erosita

space-and-spaceflight1 month ago•17 min saved

Missing Ordinary Matter Reunited: Diffuse Gas Envelopes Galaxies and Clusters

Using thousands of fast radio burst measurements, researchers mapped where ordinary (baryonic) matter resides and found widespread, diffuse gas surrounding galaxies and galaxy clusters. This diffuse gas accounts for the universe’s missing baryons, extending up to about 4 million light-years from galaxies and suggesting energetic processes like black hole jets fling baryons far beyond visible halos, which helps reconcile observations with current astrophysical models.

via Gizmodo|

#baryons #diffuse-gas #fast-radio-bursts

space1 month ago•96 min saved

Giant bow-and-arrow radio galaxy RAD-BAARG reveals colossal cluster shock wave

Astronomers have identified RAD-BAARG, a 1.8-million-light-year-wide radio galaxy with a bow-and-arrow shape likely produced by a galaxy moving supersonically through a galaxy cluster, creating a giant bow shock; discovered by citizen scientists in the RAD@home project and studied with LOFAR's LoTSS survey, its asymmetric jets highlight how cluster environments reshape radio galaxies. The system lies in a complex, multi-halo gas environment, offering insights into jet–environment interactions; findings published June 22 in Monthly Notices of the Royal Astronomical Society: Letters, demonstrating LOFAR's ability to detect faint, diffuse radio emission.

via Space|

#galaxies #galaxy-clusters #lofar

science3 months ago•4 min saved

Quiet Galaxy Cluster Unveils a Giant 3.3-Million-Light-Year Radio Halo

Astronomers using the upgraded uGMRT and MeerKAT confirm a giant radio halo spanning 3.3 million light-years in the relatively quiet galaxy cluster RXCJ0232–4420, challenging the view that such halos only form in violent mergers. The halo shows a uniform spectral index around −1.1, extends across frequencies, and correlates with hot X-ray gas, with an eastern relic detected and the cluster in an intermediate dynamical state while preserving a cool core.

via The Daily Galaxy|

#galaxy-clusters #meerkat #radio-astronomy

science3 months ago•6 min saved

Cosmic gravity passes its biggest test yet, keeping dark matter in the spotlight

Using the kinematic Sunyaev-Zeldovich effect on about 686,000 galaxies in clusters 5–7 billion light-years away, researchers measured cluster speeds and found gravity weakens with distance consistent with Newtonian/Einsteinian gravity, strengthening the case for dark matter as the source of anomalous gravitational effects, though many questions remain. The study was published in Physical Review Letters.

via ScienceAlert|

#cosmology #dark-matter #galaxy-clusters

science3 months ago•43 min saved

Hidden Giant: Vela Supercluster Maps Vast Structure Beyond Milky Way

Researchers mapped the Vela Supercluster, a colossal assembly of galaxies hidden behind the Milky Way’s dust in the Zone of Avoidance, about 800 million light-years away. It spans roughly 300 million light-years and contains mass equivalent to about 30 quadrillion suns, making it one of the universe’s largest known structures and helping refine cosmological models, with observations from SALT and MeerKAT aiding the map.

via Yahoo|

#galaxy-clusters #milky-way #radio-telescopes

space4 months ago•65 min saved

Cosmic Giant Vela Supercluster Mapped Behind the Milky Way

Astronomers have for the first time mapped the Vela Supercluster, a colossal structure roughly 300 million light-years across that houses at least 20 galaxy clusters and contains about 30 quadrillion solar masses. Hidden behind the Milky Way’s Zone of Avoidance, the map was built from 65,000 existing distance measurements and ~8,000 new redshifts (including ~2,000 from the MeerKAT radio telescope), revealing two massive cores moving toward each other and placing Vela among the universe’s largest known structures—larger than Laniakea and rivaling the Shapley Supercluster. This new view could refine models of cosmic structure and dynamics, though parts of the spread will remain obscured by dust and gas.

via Live Science|

#cosmology #galaxy-clusters #meerkat

astronomy4 months ago•9 min saved

Cosmic Gravity Holds Its Ground Across Galaxy Clusters

Using data from the Atacama Cosmology Telescope and the kinematic Sunyaev–Zeldovich effect, researchers tracked hundreds of thousands of galaxy clusters across hundreds of millions of light-years and found gravity obeys the inverse-square law on cosmological scales, aligning with Newtonian and Einsteinian gravity, reinforcing dark matter as the source of extra gravitational effects and challenging alternative gravity theories like MOND.

via SciTechDaily|

#astronomy #cosmology #dark-matter

space-and-spaceflight4 months ago•16 min saved

Cosmic Giants Conform to Classic Gravity, Dark Matter Still Fits the Puzzle

Using CMB light bent by galaxy clusters observed by ACT and SDSS, researchers found gravity on cosmic scales aligns with Newton and Einstein, challenging modified gravity theories and reinforcing dark matter as the leading explanation for mass discrepancies in the universe.

via Gizmodo|

#cosmic-microwave-background #cosmology #dark-matter

space5 months ago•6 min saved

Webb Finds the Earliest Jellyfish Galaxy Drifting Through a Young Cosmos

Astronomers using the James Webb Space Telescope have identified the farthest known jellyfish galaxy, at redshift z=1.156 (about 8.5 billion years old), in the COSMOS field. The galaxy shows blue, newly formed stars in long trailing gas streams created by ram-pressure stripping as it speeds through a dense cluster, implying harsh cluster environments existed earlier in the universe and potentially reshaping ideas about how galaxies evolved billions of years ago.

via ScienceDaily|

#early-universe #galaxy-clusters #jellyfish-galaxy

science6 months ago•7 min saved

Unprecedented Low-Frequency Radio Sky Map Reveals 13.7 Million Cosmic Sources

Astronomers released LoTSS-DR3, the most detailed low-frequency radio sky map from the LOFAR network, cataloging 13.7 million cosmic sources and offering new insights into supermassive black holes, their jets, and galaxy clusters, while tackling ionospheric distortions with advanced data-processing techniques on ~18.6 petabytes of data.

via The Daily Galaxy|

#galaxy-clusters #lofar #lotss-dr3

astronomy6 months ago•55 min saved

XRISM reveals the turbulent winds around supermassive black holes

NASA/JAXA’s XRISM X‑ray mission uses high‑resolution spectroscopy to measure gas motions around supermassive black holes, notably M87* and the Perseus cluster, unveiling the strongest turbulence seen near a black hole and the kinetic energy of surrounding gas. This helps explain how black holes heat their environments and influence galactic evolution; findings published late Jan 2026 in Nature and built on XRISM’s 2023 launch in collaboration with ESA.

via Space|

#astronomy #black-holes #galaxy-clusters

astronomy6 months ago•4 min saved

Baryons Take the Lead in Galaxy Clusters, MOND Gains Ground

A Bonn-led study analyzing 46 nearby galaxy clusters finds their mass is about twice as heavy in baryonic matter as previously thought, due to components like stellar remnants and intracluster light. The revised accounting brings cluster masses closer to MOND predictions and challenges the need for exotic dark matter, with authors suggesting a reevaluation of dark-matter-focused research funding.

via Universe Today|

#astronomy #baryonic-matter #dark-matter

astronomy6 months ago•45 min saved

Earliest Protocluster Unveiled by JWST Signals Rapid Cosmic Growth

Using the James Webb Space Telescope and NASA’s Chandra X-ray Observatory, scientists observed the most distant protocluster yet seen, JADES-ID1, forming when the universe was about 1 billion years old. Light from this building cluster has travelled 12.7 billion years to reach Earth, revealing multiple galaxies bound by gravity within a surrounding cloud of hot gas and X‑ray emission. The finding—published in Nature—suggests galaxy clusters grew far more quickly in the early universe than current models had predicted, raising new questions about how these massive structures assembled.

via Space|

#astronomy #early-universe #galaxy-clusters

space7 months ago•3 min saved

Cosmic Skeleton: Ultra-High-Res Map Traces Dark Matter Across 800,000 Galaxies

Using data from NASA’s James Webb Space Telescope, scientists produced the most detailed high-resolution map yet of distant galaxies, revealing the dark matter skeleton that links galaxy clusters and has grown over roughly 10 billion years, with nearly 800,000 galaxies identified.

via CBS News|

#cosmology #dark-matter #galaxy-clusters