Simulation Reveals Spiraling Supermassive Black Holes | NASA Goddard
A recent model is bringing scientists a step closer to understanding the kinds of light signals produced when two supermassive black holes, millions to billions of times the mass of the Sun, spiral toward a collision. A recent computer simulation fully incorporates the physical effects of Einstein’s general theory of relativity, showing that gas in such systems will glow predominantly in ultraviolet (UV) and X-ray light.
Just about every galaxy the size of our own Milky Way or larger contains a monster black hole at its center. Observations show galaxy mergers occur frequently in the universe, but so far no one has seen a merger of these giant black holes.
This simulation shows three orbits of a pair of supermassive black holes only 40 orbits from merging. The models reveal the light emitted at this stage of the process may be dominated by UV light with some high-energy X-rays, similar to what is seen in any galaxy with a well-fed supermassive black hole.
Gas glows brightly in this computer simulation of supermassive black holes only 40 orbits from merging. Models like this may eventually help scientists pinpoint real examples of these powerful binary systems.
Three regions of light-emitting gas glow as the black holes merge, all connected by streams of hot gas: a large ring encircling the entire system, called the circumbinary disk, and two smaller ones around each black hole, called mini disks. All these objects emit predominantly UV light. When gas flows into a mini disk at a high rate, the disk’s UV light interacts with each black hole’s corona, a region of high-energy subatomic particles above and below the disk. This interaction produces X-rays. When the accretion rate is lower, UV light dims relative to the X-rays.
Based on the simulation, running on the National Center for Supercomputing Applications’ Blue Waters supercomputer at the University of Illinois at Urbana-Champaign, the researchers expect X-rays emitted by a near-merger will be brighter and more variable than X-rays seen from single supermassive black holes. The pace of the changes links to both the orbital speed of gas located at the inner edge of the circumbinary disk as well as that of the merging black holes.
However, supermassive binaries nearing collision may have one thing stellar-mass binaries lack—a gas-rich environment. Scientists suspect the supernova explosion that creates a stellar black hole also blows away most of the surrounding gas. The black hole consumes what little remains so quickly there is not much left to glow when the merger happens.
Supermassive mergers will be much more difficult to find than their stellar-mass cousins. One reason ground-based observatories cannot detect gravitational waves from these events is because Earth itself is too noisy, shaking from seismic vibrations and gravitational changes from atmospheric disturbances. The detectors must be in space, like the Laser Interferometer Space Antenna (LISA) led by the European Space Agency (ESA) and planned for launch in the 2030s.
Supermassive binaries, on the other hand, result from galaxy mergers. Each supersized black hole brings along an entourage of gas and dust clouds, stars and planets. Scientists think a galaxy collision propels much of this material toward the central black holes, consuming it on a time scale similar to that needed for the binary to merge. As the black holes near, magnetic and gravitational forces heat the remaining gas, producing light astronomers should be able to see.
Scientists have detected merging stellar-mass black holes, ranging from around three to several dozen solar masses, using the National Science Foundation's Laser Interferometer Gravitational-Wave Observatory (LIGO). Gravitational waves are space-time ripples traveling at the speed of light. They are created when massive orbiting objects like black holes and neutron stars spiral together and merge.
Learn more about National Science Foundation's LIGO: https://www.nsf.gov/impacts/space-time
https://www.esa.int/Science_Exploration/Space_Science/LISA/Capturing_the_ripples_of_spacetime_LISA_gets_go-ahead
Duration: 2 minutes, 13 seconds
Release Date: Oct. 2, 2018
#NASA #Space #Astronomy #Science #Galaxies #BlackHoles #BinaryBlackHoles #BlackHole #BlackHoleMergers #GravitationalWaves #Simulation #Supercomputers #Astrophysics #Physics #Cosmos #Universe #GSFC #NSF #LIGO #UnitedStates #LISA #ESA #STEM #Education #Art #Animation #Visualization #HD #Video
GregParker.jpg)
.jpg)
.jpg)
.jpg)