AGN tagged posts

Rotating Dusty Gaseous Donut around an Active Supermassive Black Hole

ALMA revealed the rotation of the torus very clearly for the first time. Credit: ALMA (ESO/NAOJ/NRAO)

ALMA revealed the rotation of the torus very clearly for the first time. Credit: ALMA (ESO/NAOJ/NRAO)

High resolution observations show a rotating dusty gas torus around an active supermassive black hole. The existence of such rotating donuts-shape structures was first suggested decades ago, but this is the first time one has been confirmed so clearly. This is an important step in understanding the co-evolution of supermassive black holes and their host galaxies.

Researchers have known for a long time that the more massive the galaxy is, the more massive the central black hole is. This sounds reasonable at first, but host galaxies are 10 billion times bigger than the central black holes; it should be difficult for two objects of such vastly different scales to directly affect each other...

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The Structure of an Active Galactic Nucleus

The structure of an active galactic nucleus

A Hubble image of the superluminous merging galaxy Arp220. Astronomers have measured structures only a hundreds of light-years in size around the two supermassive black holes in the nuclear region, as well as evidece for an outflow. Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University

The nuclei of most galaxies host supermassive black holes containing millions to billions of solar-masses of material. The immediate environments of these black holes typically include a tori of dust and gas and, as material falls toward the black hole, the gas radiates copiously at all wavelengths...

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Supermassive Black Holes control Star Formation in large galaxies

centaurus-a-410.jpg

The power of a supermassive black hole is seen in this image of Centaurus A, one of the active galactic nuclei closest to Earth. The image combines data from several telescopes at different wavelengths, showing jets and lobes powered by the supermassive black hole at the center of the galaxy. Image credit: ESO/WFI (Optical); MPIfR/ESO/APEX/A.Weiss et al. (Submillimetre); NASA/CXC/CfA/R.Kraft et al. (X-ray)

Young galaxies blaze with bright new stars forming at a rapid rate, but star formation eventually shuts down as a galaxy evolves. A new study shows that the mass of the black hole in the center of the galaxy determines how soon this “quenching” of star formation occurs...

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Vast Luminous Nebula poses a Cosmic Mystery

MAMMOTH-1 is an extended blob of gas in the intergalactic medium called an enormous Lyman-alpha nebula (ELAN). The color map and contours denote the surface brightness of the nebula, and the red arrows show its estimated spatial extent. (Image credit: Figure 2 of Cai et al., Astrophysical Journal)

MAMMOTH-1 is an extended blob of gas in the intergalactic medium called an enormous Lyman-alpha nebula (ELAN). The color map and contours denote the surface brightness of the nebula, and the red arrows show its estimated spatial extent. (Image credit: Figure 2 of Cai et al., Astrophysical Journal)

Glowing nebula found at the heart of a huge ‘rotocluster’ of early galaxies appears to be part of the cosmic web of filaments connecting galaxies, but what’s lighting it up? Astronomers have found an enormous, glowing blob of gas in the distant universe, with no obvious source of power for the light it is emitting. Called an “enormous Lyman-alpha nebula” (ELAN), it is the brightest and among the largest of these rare objects, only a handful of which have been observed.

ELANs are huge blobs of gas...

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