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    Chandra finds black hole that’s growing at 2.4 times the Eddington limit

    September 24, 2025, Categories  Astronomy/Space

    An artist's concept of a supermassive black hole, a surrounding disk of material falling towards the black hole and a jet containing particles moving away at close to the speed of light. This black hole represents a recently-discovered quasar powered by a black hole. New Chandra observations indicate that the black hole is growing at a rate that exceeds the usual limit for black holes, called the Eddington Limit. Credit: NASA/CXC/SAO/M. Weiss
    An artist’s concept of a supermassive black hole, a surrounding disk of material falling towards the black hole and a jet containing particles moving away at close to the speed of light. This black hole represents a recently-discovered quasar powered by a black hole. New Chandra observations indicate that the black hole is growing at a rate that exceeds the usual limit for black holes, called the Eddington Limit. Credit: NASA/CXC/SAO/M. Weiss
    X-ray: NASA/CXC/INAF-Brera/L. Ighina et al.; Illustration: NASA/CXC/SAO/M. Weiss; Image Processing: NASA/CXC/SAO/N. Wolk

    A black hole is growing at one of the fastest rates ever recorded, according to a team of astronomers...

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    Cosmic Simulation Reveals How Black Holes Grow and Evolve

    July 5, 2024, Categories  Astronomy/Space

    This still shows an accretion disk around a supermassive black hole.
    This still from the simulation shows a supermassive black hole, or quasar, surrounded by a swirling disk of material called an accretion disk. Credit: Caltech/Phil Hopkins group

    A team of astrophysicists led by Caltech has managed for the first time to simulate the journey of primordial gas dating from the early universe to the stage at which it becomes swept up in a disk of material fueling a single supermassive black hole. The new computer simulation upends ideas about such disks that astronomers have held since the 1970s and paves the way for new discoveries about how black holes and galaxies grow and evolve.

    “Our new simulation marks the culmination of several years of work from two large collaborations started here at Caltech,” says Phil Hopkins, the Ira S...

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    Observations Explore Radio Jet of a Powerful Quasar

    February 27, 2024, Categories  Uncategorized

    Observations explore radio jet of a powerful quasar
    VLBI image of PKS 2215+020 at 1.7 GHz. Credit: Universe (2024). DOI: 10.3390/universe10020097

    European astronomers have conducted very long baseline interferometric (VLBI) observations of a radio jet structure in a powerful quasar known as PKS 2215+020. The collected VLBI data provide important insights into the properties of this jet, suggesting that PKS 2215+020 is a blazar. The findings were presented February 17 in the Universe journal.

    Quasars, or quasi-stellar objects (QSOs) are active galactic nuclei (AGN) of very high luminosity, emitting electromagnetic radiation observable in radio, infrared, visible, ultraviolet and X-ray wavelengths.

    They are among the brightest and most distant objects in the known universe, and serve as fundamental tools for numerous studies in as...

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    Gas on the run – ALMA spots the Shadow of a Molecular Outflow from a Quasar when the Universe was less than one billion years old

    February 7, 2024, Categories  Astronomy/Space

    The molecular gas outflow from the quasar includes hydroxyl (OH) (top). Due to the motion of the molecular gas toward the observer, the OH peak in the absorption spectrum (bottom, dashed blue line) appears at a shorter wavelength (solid blue line), a phenomenon known as the Doppler effect. (Illustration: ALMA (ESO/NAOJ/NRAO) modified from Dragan Salak, et al. The Astrophysical Journal. February 1, 2024)
    The molecular gas outflow from the quasar includes hydroxyl (OH) (top). Due to the motion of the molecular gas toward the observer, the OH peak in the absorption spectrum (bottom, dashed blue line) appears at a shorter wavelength (solid blue line), a phenomenon known as the Doppler effect. (Illustration: ALMA (ESO/NAOJ/NRAO) modified from Dragan Salak, et al. The Astrophysical Journal. February 1, 2024)

    Theoretical predictions have been confirmed with the discovery of an outflow of molecular gas from a quasar when the Universe was less than a billion years old.

    A quasar is a compact region powered by a supermassive black hole located in the center of a massive galaxy.

    They are extremely luminous, with a point-like appearance similar to stars, and are extremely distant from Earth...

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