active galactic nuclei tagged posts

Dust Clouds can explain Puzzling features of Active Galactic Nuclei

An artist's impression of what an active galactic nucleus might look like close up. The accretion disk produces the brilliant light in the center. The broad-line region is just above the accretion disk and lost in the glare. Dust clouds are being driven upward by the intense radiation. Credit: Peter Z. Harrington

An artist’s impression of what an active galactic nucleus might look like close up. The accretion disk produces the brilliant light in the center. The broad-line region is just above the accretion disk and lost in the glare. Dust clouds are being driven upward by the intense radiation. Credit: Peter Z. Harrington

Mysterious features seen in light emitted from active galactic nuclei may be due to partial obscuration by dust clouds. Many large galaxies have a bright central region called an active galactic nucleus (AGN), powered by matter spiraling into a supermassive black hole...

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Deep inside Perseus A – A Telescope Larger than the Earth makes a Sharp Image of the Formation of Black Hole Jets in the core of a radio galaxy

Artistic composition of the radio telescopes in space and on the ground observing NGC 1275, the central galaxy of the Perseus cluster of galaxies at a distance of 230 million light years. This radio image shows a newly forming jet that is about 3 light years long. The central black hole is inside the bright spot at the top of the image. The details visible in the image are smaller than the Oort’s comet cloud around our solar system. Credit: Pier Raffaele Platania INAF/IRA (compilation); ASC Lebedev Institute (RadioAstron image)

Artistic composition of the radio telescopes in space and on the ground observing NGC 1275, the central galaxy of the Perseus cluster of galaxies at a distance of 230 million light years. This radio image shows a newly forming jet that is about 3 light years long. The central black hole is inside the bright spot at the top of the image. The details visible in the image are smaller than the Oort’s comet cloud around our solar system. Credit: Pier Raffaele Platania INAF/IRA (compilation); ASC Lebedev Institute (RadioAstron image)

An international team has imaged newly forming jets of plasma from a massive black hole with unprecedented accuracy...

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Markarian 1018: Starvation Diet for Black Hole Dims Brilliant Galaxy

Markarian 1018: Starvation Diet for Black Hole Dims Brilliant Galaxy

Markarian 1018 is an “active galaxy” that has brightened and dimmed over about 30 years. The black hole at the center waS being deprived of enough fuel to illuminate its surroundings. Credit X-ray: NASA/CXC/Univ of Sydney/R.McElroy et al, Optical: ESO/CARS Survey

Astronomers may have solved the mystery of the peculiar volatile behavior of a supermassive black hole at the center of a galaxy. Combined data from NASA’s Chandra X-ray Observatory and other observatories suggest the black hole is no longer being fed enough fuel to make its surroundings shine brightly. Many galaxies have an extremely bright core, or nucleus, powered by material falling toward a supermassive black hole. These “active galactic nuclei”, AGN, are some of the brightest objects in the Universe.

Astronomers classify AGN...

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