Featured Research

from universities, journals, and other organizations

Chandra Sees Wealth Of Black Holes In Star-Forming Galaxies

Date:
June 6, 2001
Source:
NASA/Marshall Space Flight Center
Summary:
NASA’s Chandra X-ray Observatory has found new populations of suspected mid-mass black holes in several starburst galaxies, where stars form and explode at an unusually high rate. Although a few of these objects had been found previously, this is the first time they have been detected in such large numbers and could help explain their relationship to star formation and the production of even more massive black holes.

NASA’s Chandra X-ray Observatory has found new populations of suspected mid-mass black holes in several starburst galaxies, where stars form and explode at an unusually high rate. Although a few of these objects had been found previously, this is the first time they have been detected in such large numbers and could help explain their relationship to star formation and the production of even more massive black holes.

Related Articles


At the 198th meeting of the American Astronomical Society in Pasadena, Calif., three independent teams of scientists reported finding dozens of X-ray sources in galaxies aglow with star formation. These X-ray objects appear point-like and are ten to a thousand times more luminous in X-rays than similar sources found in our Milky Way and the M81 galaxy.

“Chandra gives us the ability to study the populations of individual bright X-ray sources in nearby galaxies in extraordinary detail,” said Andreas Zezas, lead author from the Harvard-Smithsonian Center for Astrophysics team that observed The Antennae, a pair of colliding galaxies, and M82, a well-known starburst galaxy.

“This allows us to build on earlier detections of these objects and better understand their relationship to starburst galaxies.” Kimberly Weaver, of NASA’s Goddard Space Flight Center in Greenbelt, Md., lead scientist of the team that studied the starburst galaxy NGC 253, discussed the importance of the unusual concentration of these very luminous X-ray sources near the center of that galaxy. Four sources, which are tens to thousands of times more massive than the Sun, are located within 3,000 light years of the galaxy core.

“This may imply that these black holes are gravitating toward the center of the galaxy where they could coalesce to form a single supermassive black hole,” Weaver suggested. “It could be that this starburst galaxy is transforming itself into a quasar-like galaxy as we watch. In NGC 253, Chandra may have found the causal connection between starburst activity and quasars.”

Chandra detected variability and a relatively large ratio of high- to low-energy X-rays in these sources - two characteristics of superheated gas falling into black holes. When combined with extreme luminosities, this tells astronomers that some of these objects must have masses many times greater than ordinary stellar black holes, if they radiate energy uniformly in all directions.

Scenarios for the formation of such “intermediate-mass” black holes include the direct collapse of a single, massive cloud of gas into a black hole, or the coalescence of a cluster of stellar black holes, but no uniformly accepted model exists.

An alternative possibility, mentioned by Giuseppina Fabbiano of the Harvard-Smithsonian team, is that the X-rays from such highly luminous sources are beamed toward us -- perhaps by a funnel formed by the infalling matter. This would imply that the mass of the underlying black hole is only about ten times the mass of the Sun, in line with the known black hole sources in our galaxy. In this event, they would represent a short-lived but common stage in the evolution of black holes in close binary star systems. Long-term monitoring of the very luminous X-ray sources should distinguish between these possibilities.

Andrew Ptak, led a team from Carnegie-Mellon University in Pittsburgh, Pa., and Penn State University, University Park, Pa., that used Chandra data to survey 37 galaxies. Ptak’s team found that 25 percent of galaxies, which were chosen for their suspected central supermassive black holes and areas of star formation, had these very luminous X-ray sources. The team plans to expand their survey with Chandra to assess the probability of finding these very bright X-ray sources in other types of galaxies.

NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the Office of Space Science, Washington, DC. TRW, Inc., Redondo Beach, Calif., is the prime contractor for the spacecraft. The Smithsonian's Chandra X-ray Center controls science and flight operations from Cambridge, Mass.

Images associated with this release are available on the World Wide Web at: http://chandra.harvard.edu and http://chandra.nasa.gov.


Story Source:

The above story is based on materials provided by NASA/Marshall Space Flight Center. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Marshall Space Flight Center. "Chandra Sees Wealth Of Black Holes In Star-Forming Galaxies." ScienceDaily. ScienceDaily, 6 June 2001. <www.sciencedaily.com/releases/2001/06/010606073550.htm>.
NASA/Marshall Space Flight Center. (2001, June 6). Chandra Sees Wealth Of Black Holes In Star-Forming Galaxies. ScienceDaily. Retrieved April 2, 2015 from www.sciencedaily.com/releases/2001/06/010606073550.htm
NASA/Marshall Space Flight Center. "Chandra Sees Wealth Of Black Holes In Star-Forming Galaxies." ScienceDaily. www.sciencedaily.com/releases/2001/06/010606073550.htm (accessed April 2, 2015).

Share This


More From ScienceDaily



More Space & Time News

Thursday, April 2, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Universe Could Be Full Of Tatooine Sunsets

The Universe Could Be Full Of Tatooine Sunsets

Newsy (Mar. 30, 2015) — University of Utah researchers say mathematical simulations show small, rocky planets, like Tatooine from "Star Wars," can form in dual-star systems. Video provided by Newsy
Powered by NewsLook.com
What NASA Wants To Learn From Its 'Year In Space' Tests

What NASA Wants To Learn From Its 'Year In Space' Tests

Newsy (Mar. 28, 2015) — Astronaut Scott Kelly and cosmonaut Mikhail Kornienko will spend a year in space running tests on human physiology and psychology. Video provided by Newsy
Powered by NewsLook.com
Raw: Astronauts Arrive at ISS for 1-Year Mission

Raw: Astronauts Arrive at ISS for 1-Year Mission

AP (Mar. 28, 2015) — The capsule carrying a Russian and an American who are to spend a year away from Earth docked Saturday with the International Space Station. (March 28) Video provided by AP
Powered by NewsLook.com
Crew Starts One-Year Space Mission

Crew Starts One-Year Space Mission

Reuters - News Video Online (Mar. 28, 2015) — Russian-U.S. crew arrives safely at the International Space Station for the start of a ground-breaking year-long stay. Paul Chapman reports. Video provided by Reuters
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