Black hole at the core of a galaxy periodically brightens up

X-ray Quasi-Periodic Eruptions (QPEs) from the black hole at the core of GSN 069 as observed with XMM-Newton and Chandra. In each panel, the X-ray amplitude is relative to the ‘quiescent’ level. [credit: G. Miniutti, CAB]

During an ESA’s XMM-Newton observation on 2018 Christmas Eve, an international team led by Giovanni Miniutti, of the Centro de Astrobiología (CAB, CSIC-INTA) in Madrid, discovered some mysterious flashes from the active black hole at the core of the galaxy GSN 069, about 250 million light years away. X-ray emission from the center of that galaxy was seen to suddenly increase its brightness by up to a factor 100, then dimmed back to its normal levels within one hour and lit up again nine hours later. Giant black holes regularly flicker like a candle but the rapid, repeating changes seen in GSN 069 had never been observed before from supermassive black hole at the core of galaxies.

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The centre of the galaxy NGC 5643 has been chosen as an ESO Picture of the Week

Centre of NGC 5643 observed by ALMA and VLT. Credit: ESO/A. Alonso-Herrero et al.; ALMA (ESO/NAOJ/NRAO)

This ESO Picture of the Week shows the centre of a galaxy named NGC 5643. This galaxy is located 55 million light-years from Earth in the constellation of Lupus (The Wolf), and is known as a Seyfert galaxy. Seyfert galaxies have very luminous centres — thought to be powered by material being accreted onto a supermassive black hole lurking within — that can also be shrouded and obscured by clouds of dust and intergalactic material. Continue reading

A 100 kpc nebula associated with the “Teacup” fading quasar

HST image and GTC/OSIRIS spectra of the “Teacup” containing the Hα+[NII] lines. We highlight prominent emission line features such as the NE and SW bubbles. For further details, see Villar-Martín et al. 2017.

The “Teacup” (SDSS J143029.88+133912.0 at z=0.085) is a nearby quasar, whose nickname comes from the peculiar morphology of the extended ionized gas. It shows a loop-shaped structure reminiscent of a teacup “`handle” which extends up to ~12 kpc (~39,000 light years) NE of the active galactic nucleus. Continue reading

The response of relativistic outflowing gas to the inner accretion disk of a black hole

Artist impression illustrating a super-massive black hole with X-ray emission emanating from its inner region (pink) and ultrafast winds streaming from the surrounding disk (purple). Credit: ESA

Active Galactic Nuclei (AGN) are thought to have a profound effect on large scales through feedback mechanisms. AGN gas outflows release vast amounts of energy into the interstellar medium and can clear out the surrounding gas, possibly regulating star formation in the host galaxy as well as preventing further gas accretion onto the black hole. Such feedback may well contribute to the intimate observed relationship between the central black hole and the host galaxy properties.

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Dusty doughnut around massive black hole spied for first time

The dust continuum emission at 694 GHz mapped by ALMA in the CND of NGC1068. See García-Burillo et al. 2016 for further details.

The dust continuum emission at 694 GHz mapped by ALMA in the circumnuclear disk of NGC1068. See García-Burillo et al. 2016 for further details.

An international team of astronomers lead by the spanish astronomer Santiago García-Burillo (OAN, Madrid), and with the participation of CAB scientists (Almudena Alonso Herrero and Luis Colina), have been able to resolve for the first time the dusty torus around the massive black hole in the nucleus of the nearby active galaxy NGC 1068.

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