Coma Cluster:
Gas Clouds Strike A Delicate Balance
This Chandra image shows the central region - about 1.5 million light years across - of the Coma Cluster. The cluster contains thousands of galaxies enveloped by a vast 100 million-degree Celsius gas cloud.
Of particular interest are the concentrations of
cooler (10 to 20 million-degrees) gas around the large
galaxies NGC 4889 (left) and NGC 4874 (right). These
clumps of gas, which are 10,000 light years in
diameter, are thought to be produced by matter ejected
from stars in the galaxies over a period of about a
billion years.
As discussed by Alexey Vikhlinin and his colleagues at
the Harvard-Smithsonian Center for Astrophysics in
Cambridge, Massachusetts, in the 2001 July 10 issue of
The Astrophysical Journal, the observation of
relatively cool gas clouds in two large galaxies
indicates that they are unlikely to be short-lived
features. The scientists suggest that the clouds exist
in a delicate balance in which the energy lost by
X-radiation is precisely balanced by energy gained by
heat conduction from the hot gas of the cluster.
Because of the large difference in temperature between
the hot gas and the cool clouds - like a snowball in a
blast furnace - this balance would require that the
heat flow from the hot gas be greatly reduced, perhaps
by the magnetic fields in the galaxies that separate
the hot and cold components.
| Fast Facts for Coma Cluster:
|
| Credit |
NASA/CXC/SAO/A.Vikhlinin et
al. |
| Scale
|
Image is 16.5 arcmin on a
side. |
| Category |
Groups
& Clusters of Galaxies |
| Coordinates
(J2000) |
RA 12h 59m 48s | Dec +27º
58' 00" |
| Constellation
|
Coma Berenices |
| Observation
Date |
6 different pointings on November
4, 1999 |
| Observation
Time |
15.8 hrs |
| Obs. ID
|
1086, 1112-1114, 555, 556
|
| Color Code
|
Intensity |
| Instrument
|
ACIS |
| Distance
Estimate |
370 million light years (redshift
z = 0.023) |
|
Release Date
|
April 04, 2002
|
|
|
