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Steve Roy
Media Relations Dept.
Marshall Space Flight Center, Huntsville, AL
(256) 544-0034
steve.roy{at}msfc.nasa.gov

For release: 01/22/03

Photo release no.: 03-010

Chandra Observatory reveals spiral galaxy's boisterous activity
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This Chandra X-ray Observatory image of M83 shows numerous point-like 
neutron star and black hole X-ray sources scattered throughout the 
disk of this spiral galaxy. The bright nuclear region of the galaxy 
glows prominently due to a burst of star formation that is estimated 
to have begun about 20 million years ago in the galaxy's time frame.

The observation revealed that the nuclear region contains a much 
higher concentration of neutron stars and black holes than the rest of 
the galaxy. Also discovered was a cloud of 7 million degree Celsius 
gas enveloping the nuclear region. 

The picture that emerges is one of enhanced star formation in the 
nuclear region that has produced more massive stars, leading to more 
supernova explosions, neutron stars and black holes. This activity 
could also account for the hot gas cloud which shows evidence for an 
excess of carbon, neon, magnesium, silicon and sulfur atoms. Mass 
evaporating from massive stars, and the ejecta from supernovas have
enriched the gas with carbon and other elements. 

Hot gas with a slightly lower temperature of 4 million degrees was 
observed along the spiral arms of the galaxy.  This suggests that star 
formation may be occurring at a more sedate rate in the spiral arms, 
consistent with the observation of proportionately fewer bright 
point-like sources there compared to the nucleus.

The Marshall Center manages the Chandra program.

(Photo credit: NASA/CXC/UCL/R. Soria et al.)

http://www1.msfc.nasa.gov/NEWSROOM/news/photos/2003/photos03-010.html

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