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Neutron Stars/X-ray Binaries
Magnetars
These illustrations show how an extremely rapidly rotating neutron star, which has formed from the collapse of a very massive star, can produce incredibly powerful magnetic fields. These objects are known as magnetars.
(Illustration: NASA/CXC/M.Weiss)
Magnetars are neutron stars with magnetic fields that are about a quadrillion times greater than the magnetic field of Earth. These awesome magnetic fields are thought to be produced when an extremely rapidly rotating neutron star is formed by the collapse of the core of a massive star. When a neutron star forms it triggers a supernova explosion that expels the outer layers of the star at high speeds.
The high rate of the rotation of the neutron star intensifies the already superstrong magnetic field to magnetar levels. When the magnetic forces get strong enough, they may cause starquakes on the surface of the neutron star that produce powerful outbursts of X-rays called X-ray flashes. These events may represent an intermediate type of supernova explosion - more energetic than ordinary supernovae, but less so than hypernovae, thought to be responsible for gamma ray bursts. Magnetar outbursts can also occur for hundreds of years after the initial explosion.
The strongest steady magnetic field produced on Earth in a lab is about a million times greater than the Earth's magnetic field. Beyond this limit ordinary magnetic material would be blown apart by magnetic forces. Only on a neutron star, where gravity is more than 100 billion times as great as on Earth, can matter withstand the magnetic forces of a magnetar, and even there the neutron star's crust can break apart under the strain.
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