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A small, dense object only twelve miles in
diameter is responsible for this beautiful X-ray nebula that spans 150
light years. At the centre of this image, made by NASA's Chandra
X-ray Observatory is a very young and powerful pulsar, known as PSR
B1509-58. The pulsar is a rapidly spinning neutron star which is
throwing energy out into the space around it to create complex and
intriguing structures, including one that resembles a large cosmic
hand. In this image, the lowest energy X-rays that Chandra detects
are red, the medium range is green, and the most energetic ones are
coloured blue. We believe this object is about 1700 years old and
is located about 17,000 light years away from us.
Neutron stars are created when massive
stars, much larger than our sun run out of fuel and collapse. This
object is spinning on its axis almost seven times every second and is
releasing energy at a prodigious rate. The combination of rapid
rotation and ultra-strong magnetic field drives an energetic wind of
electrons and ions away from the neutron star. As the electrons
move through the magnetized nebula, they radiate away their energy and
create the elaborate nebula seen by Chandra. In the innermost
regions, a faint circle surrounds the pulsar, and marks the spot where
the wind is rapidly decelerated by the slowly expanding nebula.
B1509 shares some striking similarities to the famous Crab Nebula.
However, B1509's nebula is 15 times wider than the Crab's diameter of 10
light years.
Finger-like structures extend to the
north, apparently energizing knots of material in a neighbouring gas
cloud, known as RCW 89. The transfer of energy from the wind to
these knots makes them glow brightly in X-rays (orange and red features
to the upper right). The temperature in this region appears to
vary in a circular pattern around this ring of emission, suggesting that
the pulsar may be precessing like a spinning top and sweeping an
energizing beam around the gas in RCW 89. Click
on the image for a 1Mb larger version. |
