Featured Research

from universities, journals, and other organizations

Milky Way's X-ray Ridge: Resolving A Galactic Mystery

Date:
May 1, 2009
Source:
Chandra X-ray Center
Summary:
An extremely deep image of a region near the center of the Milky Way Galaxy has resolved a long-standing mystery about an X-ray glow along the plane of our home galaxy. The glow in the region covered by the image was discovered to be caused by hundreds of point-like X-ray sources, implying that the glow along the plane of the Galaxy is due to millions of such sources.

This extremely deep Chandra X-ray Observatory image has resolved a long-standing mystery about an X-ray glow along the plane of the Milky Way. The Chandra results show that the X-ray emission in the region is caused by hundreds of point-like sources, implying that the glow along the plane of the Galaxy is due to millions of such sources. In this image, the Chandra field-of-view, a region located only about 1.4 degrees from the Galactic Center, is pulled out from an infrared image from the Spitzer Space Telescope.
Credit: X-ray: NASA/CXC/TUM/M.Revnivtsev et al.; IR: NASA/JPL-Caltech/GLIMPSE Team

An extremely deep Chandra X–ray Observatory image of a region near the center of the Milky Way Galaxy has resolved a long-standing mystery about an X-ray glow along the plane of the our home galaxy. The glow in the region covered by the Chandra image was discovered to be caused by hundreds of point-like X-ray sources, implying that the glow along the plane of the Galaxy is due to millions of such sources.

Related Articles


This image shows an infrared view from the Spitzer Space Telescope of the central region of the Milky Way, with a pullout showing a Chandra image of a region located only 1.4 degrees away from the center of the Galaxy.

The so-called Galactic ridge X-ray emission was first detected more than two decades ago using early X-ray observatories such as HEAO-1 and Exosat. The ridge was observed to extend about two degrees above and below the plane of the Galaxy and about 40 degrees along the plane of the galaxy on either side of the galactic center. It appeared to be diffuse.

One interpretation of the Galactic X-ray ridge was that it is emission from 100-million-degree gas. This interpretation is problematic because the disk of the Galaxy is not massive enough to confine such hot gas, which should flow away in a wind. Replenishing the gas would then be a problem, since plausible sources of energy such as supernovas are not nearly powerful enough.

A very deep Chandra observation, lasting for about 12 days, was used to study the nature of this ridge emission. The field was chosen to be close enough to the Galactic plane so that the ridge emission was strong, but in a region with relatively little absorption from dust and gas to maximize the number of sources that might be detected. A total of 473 sources were detected in an area on the sky only about 3% of the size of the full Moon, one of the highest densities of X-ray sources ever seen in our Galaxy.

It was found that more than 80% of the seemingly diffuse ridge of X-ray emission was resolved into individual sources. These are believed to be mostly white dwarfs pulling matter from companion stars and double stars with strong magnetic activity that are producing X-ray outbursts or flares that are similar to, but more powerful than the flares seen on the Sun. These stars are unrelated to the large-scale structures seen towards the center of the Spitzer image, which are probably caused by young massive stars.

The paper reporting these results appears in the April 30th issue of Nature. This work was led by Mikhail Revnivtsev from the Excellence Cluster Universe, Technical University Munich, in Garching, Germany, and from the Space Research Institute, in Moscow, Russia. The co-authors were Sergey Sasanov of the Space Research Institute in Moscow, Russia; Eugene Churazov of the Max Planck Institute for Astrophysics (MPA) in Garching, Germany; William Forman and Alexey Vikhlinin from the Harvard-Smithsonian Center for Astrophysics and Rashid Sunyaev from MPA.


Story Source:

The above story is based on materials provided by Chandra X-ray Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. M. Revnivtsev, S. Sazonov, E. Churazov, W. Forman, A. Vikhlinin & R. Sunyaev. Discrete sources as the origin of the Galactic X-ray ridge emission. Nature, 2009; 458 (7242): 1142 DOI: 10.1038/nature07946

Cite This Page:

Chandra X-ray Center. "Milky Way's X-ray Ridge: Resolving A Galactic Mystery." ScienceDaily. ScienceDaily, 1 May 2009. <www.sciencedaily.com/releases/2009/04/090429140847.htm>.
Chandra X-ray Center. (2009, May 1). Milky Way's X-ray Ridge: Resolving A Galactic Mystery. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2009/04/090429140847.htm
Chandra X-ray Center. "Milky Way's X-ray Ridge: Resolving A Galactic Mystery." ScienceDaily. www.sciencedaily.com/releases/2009/04/090429140847.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Space & Time News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NASA Prepares for Next Phase of Hubble Successor

NASA Prepares for Next Phase of Hubble Successor

Reuters - Innovations Video Online (Dec. 22, 2014) Scientists and engineers prepare for the next phase of the James Webb Space Telescope, the scientific successor to the Hubble. Nathan Frandino reports. Video provided by Reuters
Powered by NewsLook.com
Spokesman: 'NORAD Ready to Track Santa'

Spokesman: 'NORAD Ready to Track Santa'

AP (Dec. 19, 2014) Pentagon spokesman Rear Adm. John Kirby said that NORAD is ready to track Santa Claus as he delivers gifts next week. Speaking tongue-in-cheek, he said if Santa drops anything off his sleigh, "we've got destroyers out there to pick them up." (Dec. 19) Video provided by AP
Powered by NewsLook.com
NASA's Planet-Finding Kepler Mission Isn't Over After All

NASA's Planet-Finding Kepler Mission Isn't Over After All

Newsy (Dec. 18, 2014) More than a year after NASA declared the Kepler spacecraft broken beyond repair, scientists have figured out how to continue getting useful data. Video provided by Newsy
Powered by NewsLook.com
Rover Finds More Clues About Possible Life On Mars

Rover Finds More Clues About Possible Life On Mars

Newsy (Dec. 17, 2014) NASA's Curiosity rover detected methane on Mars and organic compounds on the surface, but it doesn't quite prove there was life ... yet. 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