supermassive black holes tagged posts

Montage showing very high energy gamma ray sources in the Milky Way, seen above the HESS telescopes in Namibia. Credit: © F. Acero, / Map of gamma ray sources / © HESS collaboration

The HESS international collaboration, to which CNRS and CEA contribute, has published the results of 15 years of gamma ray observations of the Milky Way. Its telescopes installed in Namibia have studied populations of pulsar wind nebulae and supernova remnants, as well as microquasars, never before detected in gamma rays. These studies are supplemented by precise measurements such as those of the diffuse emission at the center of our Galaxy. The entire set of data will henceforth serve as a reference for the international scientific community...

Image of the Whirlpool galaxy, or M51. X-ray light seen by NASA’s Chandra X-ray Observatory is shown in purple, and optical light from NASA’s Hubble Space Telescope is red, green and blue. The ultraluminous X-ray source, or ULX, in the new Caltech-led study is indicated. Credit: NASA/CXC/Caltech/M.Brightman et al.; Optical: NASA/STScI

Astronomers find new clues in galactic mystery of ultraluminous sources of X-rays. In the 1980s, researchers began discovering extremely bright sources of X-rays in the outer portions of galaxies, away from the supermassive black holes that dominate their centers. At first, researchers thought these cosmic objects, called ultraluminous X-ray sources, or ULXs, were hefty black holes with more than ten times the mass of the sun...

Magnetic field lines emanate from a pair of supermassive black holes nearing merger within a large gas disk in a simulation by RIT scientists. Periodic light signals in the gas disk could someday help scientists locate supermassive binary black holes. Credit: RIT Center for Computational Relativity and Gravitation

Multimessenger astrophysics. A new simulation of supermassive black holes – the behemoths at the centers of galaxies – uses a realistic scenario to predict the light signals emitted in the surrounding gas before the masses collide, said Rochester Institute of Technology researchers...

Andromeda galaxy

CU Boulder researchers have discovered a mechanism that explains the persistence of asymmetrical stellar clusters surrounding supermassive black holes in some galaxies and suggests that during post-galactic merger periods, orbiting stars could be flung into the black hole and destroyed at a rate of one per year.

A supermassive black hole’s gravity creates a nuclear star cluster surrounding it, which gravitational physics would expect to be spherically symmetric. However, several galaxies – including nearby Andromeda – have been observed with an asymmetrical star cluster that takes the form of a disk instead. Eccentric disks are suspected to be formed in the wake of a recent merger between two gas-rich galaxies.

Within the disk, each star follows an elliptical orbit that re...