Andrew Yee[_1_]
April 18th 08, 05:42 PM
Megan Watzke
Chandra X-ray Center, Cambridge, Mass.
617-496-7998
February 21, 2008
Kes 75: One Weird Star Starts Acting Like Another
[http://chandra.harvard.edu/photo/2008/kes75/]
This deep Chandra X-ray Observatory image shows the supernova remnant Kes
75, located almost 20,000 light years away. The explosion of a massive star
created the supernova remnant, along with a pulsar, a rapidly spinning
neutron star.
The low energy X-rays are colored red in this image and the high energy
X-rays are colored blue. The pulsar is the bright spot near the center of
the image. The rapid rotation and strong magnetic field of the pulsar have
generated a wind of energetic matter and antimatter particles that rush out
at near the speed of light. This pulsar wind has created a large, magnetized
bubble of high-energy particles called a pulsar wind nebulae, seen as the
blue region surrounding the pulsar.
The magnetic field of the pulsar in Kes 75 is thought to be more powerful
than most pulsars, but less powerful than magnetars, a class of neutron star
with the most powerful magnetic fields known in the Universe. Scientists are
seeking to understand the relationship between these two classes of object.
Using NASA's Rossi X-ray Timing Explorer (RXTE), Fotis Gavriil of Goddard
Space Flight Center, and colleagues discovered powerful bursts of X-rays
from this pulsar that are similar to bursts previously seen from magnetars.
These bursts are believed to occur when the surface of the neutron star is
disrupted by sudden changes in the magnetic field. These bursts were
accompanied by magnetar-like changes in the rate of spin of the pulsar.
Fortuitously, Chandra observed the pulsar near the time of the bursts and it
was much brighter than it had been in Chandra observations obtained six
years earlier. This brightening, and changes in the X-ray spectrum of the
pulsar obtained with Chandra are also consistent with behavior expected for
a magnetar. The behavior of this object may, therefore, fill a gap between
that of pulsars and magnetars.
Harsha Sanjeev Kumar and Samar Safi-Harb of the University of Manitoba have
independently used Chandra observations to argue that the pulsar in Kes 75
is revealing itself as a magnetar.
Chandra X-ray Center, Cambridge, Mass.
617-496-7998
February 21, 2008
Kes 75: One Weird Star Starts Acting Like Another
[http://chandra.harvard.edu/photo/2008/kes75/]
This deep Chandra X-ray Observatory image shows the supernova remnant Kes
75, located almost 20,000 light years away. The explosion of a massive star
created the supernova remnant, along with a pulsar, a rapidly spinning
neutron star.
The low energy X-rays are colored red in this image and the high energy
X-rays are colored blue. The pulsar is the bright spot near the center of
the image. The rapid rotation and strong magnetic field of the pulsar have
generated a wind of energetic matter and antimatter particles that rush out
at near the speed of light. This pulsar wind has created a large, magnetized
bubble of high-energy particles called a pulsar wind nebulae, seen as the
blue region surrounding the pulsar.
The magnetic field of the pulsar in Kes 75 is thought to be more powerful
than most pulsars, but less powerful than magnetars, a class of neutron star
with the most powerful magnetic fields known in the Universe. Scientists are
seeking to understand the relationship between these two classes of object.
Using NASA's Rossi X-ray Timing Explorer (RXTE), Fotis Gavriil of Goddard
Space Flight Center, and colleagues discovered powerful bursts of X-rays
from this pulsar that are similar to bursts previously seen from magnetars.
These bursts are believed to occur when the surface of the neutron star is
disrupted by sudden changes in the magnetic field. These bursts were
accompanied by magnetar-like changes in the rate of spin of the pulsar.
Fortuitously, Chandra observed the pulsar near the time of the bursts and it
was much brighter than it had been in Chandra observations obtained six
years earlier. This brightening, and changes in the X-ray spectrum of the
pulsar obtained with Chandra are also consistent with behavior expected for
a magnetar. The behavior of this object may, therefore, fill a gap between
that of pulsars and magnetars.
Harsha Sanjeev Kumar and Samar Safi-Harb of the University of Manitoba have
independently used Chandra observations to argue that the pulsar in Kes 75
is revealing itself as a magnetar.