Featured Research

from universities, journals, and other organizations

Triple Interactions Of Supermassive Black Holes Found To Be Common In Early Universe

Date:
January 10, 2007
Source:
Northwestern University
Summary:
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, which exist at the centers of nearly all galaxies, often come together during triple galaxy interactions. 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.

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.

In addition to Rasio, Hoffman and Volonteri, the research team includes Stefan Umbreit, a postdoctoral fellow at Northwestern.


Story Source:

The above story is based on materials provided by Northwestern University. Note: Materials may be edited for content and length.


Cite This Page:

Northwestern University. "Triple Interactions Of Supermassive Black Holes Found To Be Common In Early Universe." ScienceDaily. ScienceDaily, 10 January 2007. <www.sciencedaily.com/releases/2007/01/070108145725.htm>.
Northwestern University. (2007, January 10). Triple Interactions Of Supermassive Black Holes Found To Be Common In Early Universe. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2007/01/070108145725.htm
Northwestern University. "Triple Interactions Of Supermassive Black Holes Found To Be Common In Early Universe." ScienceDaily. www.sciencedaily.com/releases/2007/01/070108145725.htm (accessed July 23, 2014).

Share This




More Space & Time News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Cargo Craft Undocks from Space Station

Raw: Cargo Craft Undocks from Space Station

AP (July 22, 2014) — A Russian Soyuz cargo-carrying spacecraft undocked from the International Space Station on Monday. The craft is due to undergo about ten days of engineering tests before it burns up in the Earth's atmosphere. (July 22) Video provided by AP
Powered by NewsLook.com
NASA Ceremony Honors Moon Walker Neil Armstrong

NASA Ceremony Honors Moon Walker Neil Armstrong

AP (July 21, 2014) — NASA honored one of its most famous astronauts Monday by renaming a historic building at the Kennedy Space Center in Florida. It now bears the name of Neil Armstrong, the first man to walk on the moon. (July 21) Video provided by AP
Powered by NewsLook.com
Neil Armstrong's Post-Apollo 11 Life

Neil Armstrong's Post-Apollo 11 Life

Newsy (July 19, 2014) — Neil Armstrong gained international fame after becoming the first man to walk on the moon in 1969. But what was his life like after the historic trip? Video provided by Newsy
Powered by NewsLook.com
This Week @ NASA, July 18, 2014

This Week @ NASA, July 18, 2014

NASA (July 18, 2014) — Apollo 11 yesterday, Next Giant Leap tomorrow, Science instruments for Europa mission, and more... Video provided by NASA
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins