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NGC 4649:
Black Holes in Distant Galaxy Point to Wild Youth
Chandra's image of the elliptical galaxy NGC 4649
reveals a large, bright cloud of hot gas and 165
point-like sources. As in the elliptical galaxies,
NGC 4697 and NGC 1553, most of the point-like sources
are due to black holes and neutron stars in binary star
systems.
Black holes and neutron stars are the end state of the
brightest and most massive stars. Chandra's detection
of numerous neutron stars and black holes in this and
other elliptical galaxies shows that these galaxies
once contained many very bright, massive stars, in
marked contrast to the present population of low-mass
faint stars that now dominate elliptical
galaxies.
Many of the X-ray binaries are in "globular star clusters," round balls of stars that contain about one
million stars in a volume where typically only one
would be found. This suggests that the extraordinarily
dense environment of globular clusters may be a good
place for black holes or neutron stars to capture a
companion star.
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Elliptical Galaxies
NGC 4697 & NGC 1553
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The hot gas cloud filling the galaxy has a temperature
of about 10 million degrees Celsius. In the bright
central region there appear to be bright fingers of
X-ray emission which could be due to rising cells of
hot gas.
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Fast Facts for NGC
4649:
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Credit
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NASA/CXC/UVa/S.Randall et al.
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Scale
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Image is 8 arcmin on a side.
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Category
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Normal Galaxies & Starburst Galaxies
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Coordinates
(J2000)
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RA 12h 43m 40.3s | Dec +11º 32'
58" |
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Constellation
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Virgo
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Observation
Date
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April 20, 2000
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Observation
Time
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9.4 hours
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Obs.
ID
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785
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Color
Code
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Intensity
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Instrument
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ACIS
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Distance
Estimate
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About 60 million light years.
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Also Known
As
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PGC 42831
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Release Date
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June 04, 2002
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