In recent years, black hole mergers in our universe have been detected via ripples in spacetime known as gravitational waves. Now, for the first time, astronomers believe they’ve observed visible light from a black hole merger, in a peculiar 3-black-hole system. Source: https://earthsky.org/space/1st-time-visible-light-explosion-black-hole-merger…
Tag: the black hole
Measuring the spin of a black hole
A black hole, at least in our current understanding, is characterized by having “no hair,” that is, it is so simple that it can be completely described by just three parameters, its mass, its spin and its electric charge. Even though it may have formed out of a complex mix of matter and energy, all other details are lost when the…
Innovative model provides insight into the behavior of the black hole at the center of our galaxy
Like most galaxies, the Milky Way hosts a supermassive black hole at its center. Called Sagittarius A*, the object has captured astronomers’ curiosity for decades. And now there is an effort to image it directly. Source: https://phys.org/news/2020-06-insight-behavior-black-hole-center.html…
Cosmic quasars embrace 1970s fashion trend
Researchers from Russia, Germany, Finland and the U.S. have studied more than 300 quasars—spinning black holes that produce beams of plasma. The team has found that the shape of these so-called astrophysical jets changes from parabolic to conical at some distance from the black hole, reminiscent of the iconic flared jeans of the ’70s. By effectively measuring these “cosmic pants,” the…
Black holes are like a hologram
The theory of relativity describes black holes as being spherical, smooth and simple. Quantum theory describes them as being extremely complex and full of information. New research now proposes a surprising solution to this apparent duality. Source: https://earthsky.org/space/black-holes-are-like-a-hologram…
Galactic star formation and supermassive black hole masses
Astronomers studying how star formation evolved over cosmic time have discovered that quiescent galaxies (galaxies that are currently not making many new stars) frequently have active galactic nuclei. These AGN accrete material onto hot circumnuclear disks, and the resultant energy is released in bursts of radiation, or as jets of particles moving at close to the speed of light. The suspicion…
Scientists shed light on growth of black holes
Scientists at the Center for Astrophysics | Harvard & Smithsonian, and the Black Hole Initiative (BHI), have shed light on how black holes grow over time by developing a new model to predict if growth by accretion or by mergers is dominant, according to the results of a study presented today at the virtual 236th meeting of the American Astronomical Society…
ALMA spots the twinkling heart of our Milky Way
Astronomers used the ALMA telescope in Chile to observe irregular flickers in millimeter-waves from the center of our Milky Way galaxy: the twinkling heart of the galaxy. Source: https://earthsky.org/space/alma-gaseous-disk-black-hole-milky-way…
Why clouds form near black holes
Clouds in the greater universe are clumpy areas of greater density than their surroundings. Space telescopes have observed these cosmic clouds in the vicinity of supermassive black holes. Source: https://earthsky.org/space/cosmic-clouds-form-near-black-holes…
Where neutrinos come from
Russian astrophysicists have come close to determining the origin of high-energy neutrinos from space. The team compared data on the elusive particles gathered by the Antarctic neutrino observatory IceCube and on long electromagnetic waves measured by radio telescopes. Cosmic neutrinos turned out to be linked to flares at the centers of distant active galaxies, which are believed to host supermassive black…