News tagged with galactic nuclei

Black holes hide in our cosmic backyard

Monster black holes sometimes lurk behind gas and dust, hiding from the gaze of most telescopes. But they give themselves away when material they feed on emits high-energy X-rays that NASA's NuSTAR (Nuclear Spectroscopic ...

dateJan 08, 2017 in Astronomy
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What are active galactic nuclei?

In the 1970s, astronomers became aware of a compact radio source at the center of the Milky Way Galaxy – which they named Sagittarius A. After many decades of observation and mounting evidence, it was theorized that the ...

dateNov 09, 2016 in Astronomy
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Chance microlensing events probe galactic cores

Some galaxies pump out vast amounts of energy from a very small volume of space, typically not much bigger than our own solar system. The cores of these galaxies, so called Active Galactic Nuclei or AGNs, are often hundreds ...

dateJul 01, 2016 in Astronomy
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Researchers quantify unidentified gamma-ray sources

In 2011, Francesco Massaro, a researcher at the University of Turin (Italy), and Raffaele D'Abrusco, a post-doc in the astrophysics group at the University Federico II of Naples (Italy), using all-sky data produced by the ...

dateFeb 02, 2016 in Astronomy
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How the brightest lights in the universe 'flicker'

Active galactic nuclei are the brightest objects in the universe. They are not lit up permanently, but rather 'flicker' extremely slowly. This insight helps ETH researchers better understand the influence these nuclei and ...

dateJun 24, 2015 in Astronomy
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Ultra-luminous X-ray sources in starburst galaxies

Ultra-luminous X-ray sources (ULXs) are point sources in the sky that are so bright in X-rays that each emits more radiation than a million suns emit at all wavelengths. ULXs are rare. Most galaxies (including our own Milky ...

dateDec 22, 2014 in Astronomy
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