 |
|
Astronomers find triple interactions of supermassive black holes to be common in early universe
January 09, 2007EVANSTON, Ill. - New cosmological computer simulations produced by a team of astronomers from Northwestern University, Harvard University and the University of Michigan show for the first time that supermassive black holes (SMBHs), which exist at the centers of nearly all galaxies, often come together during triple galaxy interactions.
Frederic Rasio, a theoretical astrophysicist and professor of physics and astronomy in the Weinberg College of Arts and Sciences at Northwestern, presented the findings today (Jan. 8) at the meeting of the American Astronomical Society in Seattle.
The theoretical results are of special interest because of the recent discovery by astronomers at the California Institute of Technology of a possible triple quasar, findings that also were reported at the Seattle meeting.
"SMBHs become visible as quasars when they accrete large quantities of gas from their host galaxies, releasing prodigious amounts of energy in radiation," said Rasio. "The observation of three quasars in very close proximity shows that the kinds of interactions predicted by our computer simulations are indeed taking place, even in the nearby, present-day universe."
The existence of binary SMBHs, formed when two galaxies come together, merge and bring together their central SMBHs, has been discussed by astronomers for many years. The new work reported by Rasio shows that interactions between three SMBHs are also quite frequent, occurring perhaps up to a few times per year within the observable universe. While the merger of a binary SMBH following the collision between two galaxies simply leads to the formation of a bigger SMBH at the center of a bigger galaxy, triple black hole interactions can be much more violent and interesting.
"Three is so much better than two because the dynamics of three gravitationally interacting bodies is chaotic, as opposed to the much more regular motion of two bodies simply orbiting each other," said Rasio.
These violent triple interactions were especially frequent at early cosmological times, when our universe was only about one-tenth of its present age, and galaxies were smaller and collided much more frequently than today. At that earlier epoch, galaxies were living in a very crowded environment, as the universe had yet to expand to its present size. Smaller galaxies merged together to form some of the much bigger galaxies we see today. Although slower today, this process is ongoing. Even our own galaxy, the Milky Way, will experience a "major merger" event when it collides with its nearest neighbor, the Andromeda galaxy, in about three billion years.
Triple encounters of SMBHs often end in the complete coalescence of an SMBH pair, guaranteeing a high cosmic merger rate of black holes. They can also lead to SMBH binaries being kicked out of their parent galaxies and wandering "naked" through the universe.
"Triple black hole systems undergo complex, chaotic interactions often ending in the high-velocity ejection of one component, often straight out of the host galaxy," said Loren Hoffman, a doctoral student at Harvard and a member of the research team.
"The detection of wandering black hole binaries flying in empty space would give us a unique signature of triple interactions in the early universe," said team member Marta Volonteri, assistant professor of astronomy at the University of Michigan. "Gravitational waves emission seems to be the only way of spotting these wandering binaries."
Merging SMBH binaries are key sources of gravitational radiation that astronomers hope to detect with future observatories such as the Laser Interferometer Space Antenna (LISA), a billion-dollar joint venture of NASA and the European Space Agency, which is currently in a design phase and is expected to begin observations in or around 2017.
Northwestern University
"SMBHs become visible as quasars when they accrete large quantities of gas from their host galaxies, releasing prodigious amounts of energy in radiation," said Rasio. "The observation of three quasars in very close proximity shows that the kinds of interactions predicted by our computer simulations are indeed taking place, even in the nearby, present-day universe."
The existence of binary SMBHs, formed when two galaxies come together, merge and bring together their central SMBHs, has been discussed by astronomers for many years. The new work reported by Rasio shows that interactions between three SMBHs are also quite frequent, occurring perhaps up to a few times per year within the observable universe. While the merger of a binary SMBH following the collision between two galaxies simply leads to the formation of a bigger SMBH at the center of a bigger galaxy, triple black hole interactions can be much more violent and interesting.
"Three is so much better than two because the dynamics of three gravitationally interacting bodies is chaotic, as opposed to the much more regular motion of two bodies simply orbiting each other," said Rasio.
These violent triple interactions were especially frequent at early cosmological times, when our universe was only about one-tenth of its present age, and galaxies were smaller and collided much more frequently than today. At that earlier epoch, galaxies were living in a very crowded environment, as the universe had yet to expand to its present size. Smaller galaxies merged together to form some of the much bigger galaxies we see today. Although slower today, this process is ongoing. Even our own galaxy, the Milky Way, will experience a "major merger" event when it collides with its nearest neighbor, the Andromeda galaxy, in about three billion years.
Triple encounters of SMBHs often end in the complete coalescence of an SMBH pair, guaranteeing a high cosmic merger rate of black holes. They can also lead to SMBH binaries being kicked out of their parent galaxies and wandering "naked" through the universe.
"Triple black hole systems undergo complex, chaotic interactions often ending in the high-velocity ejection of one component, often straight out of the host galaxy," said Loren Hoffman, a doctoral student at Harvard and a member of the research team.
"The detection of wandering black hole binaries flying in empty space would give us a unique signature of triple interactions in the early universe," said team member Marta Volonteri, assistant professor of astronomy at the University of Michigan. "Gravitational waves emission seems to be the only way of spotting these wandering binaries."
Merging SMBH binaries are key sources of gravitational radiation that astronomers hope to detect with future observatories such as the Laser Interferometer Space Antenna (LISA), a billion-dollar joint venture of NASA and the European Space Agency, which is currently in a design phase and is expected to begin observations in or around 2017.
Northwestern University
Science News and Science Current Events Tag Cloud
This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size.
Oxytocin Lou Gehrig's disease Selenium Rice Genes Kidney Stones Pluto Herceptin Stem cells Climate Myosin Breast Cancer Nicotine Blood transfusion CPAP Taste Venus Express Nanoparticle Drug Resistance Xmm-newton Superconductivity Cancer Gene Biodiversity Quality Of Life Carotid endarterectomy
See More: Science News Tags
Supermassive Black Hole Current Events and Supermassive Black Hole News RSSGhost Remains After Black Hole Eruption
NASA's Chandra X-ray Observatory has found a cosmic "ghost" lurking around a distant supermassive black hole. This is the first detection of such a high-energy apparition, and scientists think it is evidence of a huge eruption produced by the black hole.
XMM-Newton takes astronomers to a black hole's edge
Using new data from ESA's XMM-Newton spaceborne observatory, astronomers have probed closer than ever to a supermassive black hole lying deep at the core of a distant active galaxy.
Rare radio supernova in nearby galaxy is nearest supernova in five years
The chance discovery last month of a rare radio supernova - an exploding star seen only at radio wavelengths and undetected by optical or X-ray telescopes - underscores the promise of new, more sensitive radio surveys to find supernovas hidden by gas and dust.
Erratic Black Hole Regulates Itself
New results from NASA's Chandra X-ray Observatory have made a major advance in explaining how a special class of black holes may shut off the high-speed jets they produce. These results suggest that these black holes have a mechanism for regulating the rate at which they grow.
NASA's Fermi Mission, Namibia's HESS Telescopes Explore a Blazar
An international team of astrophysicists using telescopes on the ground and in space have uncovered surprising changes in radiation emitted by an active galaxy.
Frantic activity revealed in dusty stellar factories
Thanks to the Very Large Telescope's acute and powerful near-infrared eye, astronomers have uncovered a host of new young, massive and dusty stellar nurseries in nearby galaxy NGC 253. The centre of this galaxy appears to harbour a twin of our own Milky Way's supermassive black hole.
Astronomers detect matter torn apart by black hole
Astronomers have used two different telescopes simultaneously to study the violent flares from the supermassive black hole in the centre of the Milky Way. They have detected outbursts from this region, known as Sagittarius A*, which reveal material being stretched out as it orbits in the intense gravity close to the central black hole.
Cosmic Lens Reveals Distant Galactic Violence
By cleverly unraveling the workings of a natural cosmic lens, astronomers have gained a rare glimpse of the violent assembly of a young galaxy in the early Universe. Their new picture suggests that the galaxy has collided with another, feeding a supermassive black hole and triggering a tremendous burst of star formation.
Closest Look Ever at the Edge of a Black Hole
Astronomers have taken the closest look ever at the giant black hole in the center of the Milky Way. By combining telescopes in Hawaii, Arizona, and California, they detected structure at a tiny angular scale of 37 micro-arcseconds - the equivalent of a baseball seen on the surface of the moon, 240,000 miles distant.
Hubble sees magnetic monster in erupting galaxy
The Hubble Space Telescope has found the answer to a long-standing puzzle by resolving giant but delicate filaments shaped by a strong magnetic field around the active galaxy NGC 1275. It is the most striking example of the influence of these immense tentacles of extragalactic magnetic fields, say researchers.
More Supermassive Black Hole Current Events and Supermassive Black Hole News Articles
 |
Supermassive Black Hole by Warner Bros. |
 |
Supermassive Black Hole (Album Version) by WM UK |
 |
Supermassive Black Hole (Album Version) by Warner Bros. |
 |
Supermassive Black Hole by Muse First single taken from their 2006 album Black Holes And Revelations. Features 'Supermassive Black Holes' coupled with the non-album 'Crying Shame'. Warner. |
 |
Supermassive Black Hole Starring: Muse |
 |
The Edge of Infinity: Supermassive Black Holes in the Universe by Fulvio Melia (Author) This timely book is suitable for the general reader wishing to find answers to some of the intriguing questions now being asked about black holes. Although once recognized as the most destructive force in nature, following a cascade of astonishing discoveries, the opinion of supermassive black holes has undergone a dramatic shift. Astronomers are discovering that these objects may have been critical to the formation of structure in the early universe, spawning bursts of star formation, planets, and even life itself. Fulvio Melia is Associate Head of Physics and Professor of Astronomy at the University of Arizona. He is author of Electrodynamics (University of Chicago, 2001), and a forthcoming title, The Black Hole at the Center of Our Galaxy (Princeton). |
 |
Supermassive Black Holes in the Distant Universe (Astrophysics and Space Science Library) by Springer This book provides a unique overview of recent developments in studies of AGN and the evolution of supermassive black holes, with particular emphasis on the revolutionary results from the Chandra and XMM-Newton X-ray Observatories. Each chapter is a comprehensive analysis and review by an expert in the field that should provide easy access to the subject. The chapters progressively follow a single theme---the mapping of the accretion history of the universe---from both theoretical and observational points of view. The chapters are written at a level that should be accessible to graduate students and non-specialists, yet the depth and innovation of the analyses will also make it highly informative to the specialist. The topical nature of the subject matter means that the material... |
 |
Twilight Original Motion Picture Soundtrack by Chop Shop/Atlantic |
 |
Twilight Original Motion Picture Soundtrack (Amazon MP3 Exclusive Version) by Atlantic Records |
 |
The Galactic Supermassive Black Hole by Fulvio Melia (Author) Here, one of the world's leading astrophysicists provides the first comprehensive and logically structured overview of the many ideas and discoveries pertaining to the supermassive black hole at the galactic center known as Sagittarius A*. By far the closest galactic nucleus in the universe, Sagittarius A* alone can provide us with a realistic expectation of learning about the physics of strong gravitational fields, and the impact of such fields on the behavior of matter and radiation under severe physical conditions. Its proximity may even provide the opportunity to directly test one of general relativity's most enigmatic predictions--the existence of closed pockets of space-time hidden behind an event horizon. The plethora of research on Sagittarius A* since its discovery in... |
| © 2009 BrightSurf.com |