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RX J1242-11:
Giant Black Hole Rips Star Apart
X-ray data from Chandra, the European Space Agency's XMM-Newton, and the
German Roengtensatellite (ROSAT) X-ray observatories provide direct
evidence for the catastrophic destruction of a star that wandered too
close to a supermassive black hole.
The accompanying illustration (top) depicts how such an event may have
occurred. A close encounter with another star put the doomed star
(orange circle) on a path that took it near a supermassive black hole.
The enormous gravity of the giant black hole stretched the star until it
was torn apart. Because of the momentum and energy of the accretion
process, only a few percent of the disrupted star's mass (indicated by
the white stream) was swallowed by the black hole, while the rest of was
flung away into the surrounding galaxy.
Observations with Chandra (lower left image) and XMM-Newton, combined
with earlier images from ROSAT, confirmed that a powerful X-ray outburst
had occurred in the center of the galaxy RX J1242-11, which appears
normal in a ground-based optical image (lower right, with the white
circle defining the location of the Chandra image). This X-ray outburst,
one of the most powerful ever detected in a galaxy, was caused when gas
from the disrupted star was heated to multimillion degree temperatures
as it fell toward the black hole.
The force that disrupted the star in RX J1242-11 is an extreme example of
the tidal force caused by differences in gravity acting on the front and
back of an object. The tidal force from the Moon causes tides in the
oceans on Earth, and tidal force from Jupiter pulled Comet
Shoemaker-Levy apart before it plunged into the giant planet.
The tidal disruption of a star is estimated to occur about once every
ten thousand years in a typical galaxy. As astronomers accumulate
observations of thousands of galaxies, many more of these events should
be detected.
| Fast Facts for RX J1242-11:
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Credit
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Illustration: NASA/CXC/M.Weiss;
X-ray: NASA/CXC/MPE/S.Komossa et al.;
Optical: ESO/MPE/S.Komossa |
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Scale
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Bottom panels are 25 arcsec per side |
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Category
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Black Holes |
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Coordinates
(J2000)
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RA 12h 42m 36.90s | Dec -11º 19' 35.00" |
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Constellation
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Virgo |
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Observation
Date
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March 09, 2001 |
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Observation
Time
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1.25 hrs |
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Obs.
ID
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1559 |
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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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Reference
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S. Komossa et al.2004, March 1 Astrophys. J. Letters |
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Distance Estimate
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About 700 million light years (redshift z = 0.05) |
| Release Date |
February 18, 2004 |
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