active galaxies, supermassive black holes at least thousands of times the mass of our Sun dominate. Many, called Seyfert Type I, are very bright in visible light. Others, called Seyfert Type II, are rather dim. The difference might be caused by some black holes accreting much more matter than others. Alternatively, the black holes in the center of Seyfert Type II galaxies might be obscured by a surrounding torus. To help choose between these competing hypotheses, the nearby Seyfert II galaxy NGC 4388 has been observed in X-ray light recently by many recent Earth-orbiting X-ray observatories, including CGRO, SIGMA, BeppoSAX, INTEGRAL, Chandra, and XMM-Newton. Recent data from INTEGRAL and XMM-Newton have found that the X-ray flux in some X-ray colors varies rapidly, while flux in other X-ray colors is quite steady. The constant flux and apparent absorption of very specific X-ray colors by cool iron together give evidence that the central black hole in NGC 4388 is seen through a thick torus composed of molecular gas and dust.
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Publications with keywords: NGC 4388 - black hole
Publications with words: NGC 4388 - black hole
- The Doubly Warped World of Binary Black Holes
- The Galaxy, the Jet, and a Famous Black Hole
- When Black Holes Collide
- M87s Central Black Hole in Polarized Light
- GW190521: Unexpected Black Holes Collide
- APOD: 2020 August 25 Á Visualization: A Black Hole Accretion Disk
- A Black Hole Disrupts a Passing Star