Featured Research

from universities, journals, and other organizations

Magnetic "Bubbles" May Be Key Force In Galaxy Clusters

Date:
January 14, 2002
Source:
Ohio University
Summary:
Astronomers have suspected that magnetic fields in space play a key role in the makeup of galaxy clusters – the basic building blocks of the universe. Now, an Ohio University-led research team has uncovered what may be the origin of those fields, a finding that has eluded scientists for more than a decade.

WASHINGTON, D.C. – Astronomers have suspected that magnetic fields in space play a key role in the makeup of galaxy clusters – the basic building blocks of the universe. Now, an Ohio University-led research team has uncovered what may be the origin of those fields, a finding that has eluded scientists for more than a decade.

Related Articles


The scientists analyzed data collected from NASA's Chandra X-ray Observatory and discovered a series of enormous cosmic "bubbles," formed more than 100 million years ago, that may contain and transport magnetic fields. These bubbles also may play a role in the creation of new stars in today's galaxies, and may have been critical in the early stages of the universe.

"We think magnetism, in some locations of the universe, could have been as important as gravity in shaping the overall structure," said Brian McNamara, an Ohio University astronomer who presented the findings today at the annual meeting of the American Astronomical Society in Washington, D.C.

Using the Chandra observatory, an orbiting spacecraft that houses the most powerful X-ray telescope in existence, McNamara and his collaborators have been examining the forces at work in several galaxy clusters. Galaxy clusters are made of individual galaxies, hot gases and dark matter.

The researchers initially discovered that the X-ray emissions from several galaxy clusters were full of holes, or cavities, that contained bright radio emissions. These cavities probably were created by an explosion of high-energy particles, which left the radio emissions in its wake.

However, the Chandra data on another galaxy cluster known as Abell 2597, located more than 1 billion light years away from Earth, showed a surprising difference. The cluster's cavities – which the researchers dubbed "ghost cavities" – contained only faint radio emissions. They seemed to float out of the centers of galaxy clusters like bubbles in a glass of soda pop, McNamara said. But these bubbles are 60,000 light years across in size, almost as big as the Milky Way galaxy.

The data suggest that the ghost cavities are filled with magnetic fields, which are released into the cosmos when the cavities burst apart. This could explain the strong magnetic forces that make up the structure of galaxy clusters, according to the astronomers.

"We've known for the past 15 to 20 years that magnetic fields exist, but we didn't understand how they got there," said McNamara, an associate professor of physics and astronomy in the College of Arts and Sciences whose research is funded by NASA. "This could be a viable mechanism."

The ghost cavities also may play an indirect role in star formation, according to the scientists. As the cavities move out of the center of the galaxy cluster, the surrounding gases cool and matter becomes dense, falling into a supermassive black hole in the cluster center. That triggers an explosion of radio emission, which sprays matter through the galaxy cluster. Under certain conditions, the matter may form new stars.

This process may happen from a dozen to hundreds of times during the life of the galaxy cluster, McNamara said, and most likely occurs in other galaxy clusters.

The key role of magnetic forces in galaxy clusters suggests that they also may have been an important mechanism in creating cosmic structure in the distant past, when the universe was smaller and the radio emission was more powerful, McNamara added.

Next the scientists will conduct a more detailed analysis of the properties of ghost cavities and their role in galaxy clusters.

"We have a sketch of what's going on, but the details are foggy at this point," McNamara said.

Collaborators on the project are Michael Wise of the Massachusetts Institute of Technology, Paul Nulsen of the University of Wollongong in Australia, Larry David of the Harvard-Smithsonian Center for Astrophysics, Chris Carilli of the National Radio Astronomy Observatory, Craig Sarazin of the University of Virginia, and a group of astronomers from the Space Telescope Science Institute and the University of Virginia.


Story Source:

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


Cite This Page:

Ohio University. "Magnetic "Bubbles" May Be Key Force In Galaxy Clusters." ScienceDaily. ScienceDaily, 14 January 2002. <www.sciencedaily.com/releases/2002/01/020109074143.htm>.
Ohio University. (2002, January 14). Magnetic "Bubbles" May Be Key Force In Galaxy Clusters. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2002/01/020109074143.htm
Ohio University. "Magnetic "Bubbles" May Be Key Force In Galaxy Clusters." ScienceDaily. www.sciencedaily.com/releases/2002/01/020109074143.htm (accessed October 24, 2014).

Share This



More Space & Time News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: China Launches Moon Orbiter

Raw: China Launches Moon Orbiter

AP (Oct. 24, 2014) China launched an experimental spacecraft Friday to fly around the moon and back to Earth in preparation for the country's first unmanned return trip to the lunar surface. (Oct. 24) Video provided by AP
Powered by NewsLook.com
China Prepares Unmanned Mission To Lunar Orbit

China Prepares Unmanned Mission To Lunar Orbit

Newsy (Oct. 23, 2014) The mission is China's next step toward automated sample-return missions and eventual manned missions to the moon. Video provided by Newsy
Powered by NewsLook.com
Russian Cosmonauts Kick Off Final Spacewalk of 2014

Russian Cosmonauts Kick Off Final Spacewalk of 2014

Reuters - US Online Video (Oct. 22, 2014) Russian cosmonauts Maxim Suraev and Alexander Samokutyaev step outside the International Space Station to perform work on the exterior of the station's Russian module. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
Comet Siding Spring Grazes Mars' Atmosphere

Comet Siding Spring Grazes Mars' Atmosphere

Newsy (Oct. 19, 2014) A comet from the farthest reaches of the solar system passed extremely close to Mars this weekend, giving astronomers a rare opportunity to study it. Video provided by Newsy
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:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

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