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| Artist's Concept of a Magnetar |
When a super massive star, after supernova, doesn't collapse under its own weight to form a black hole, the core of the star is compressed to form a neutron star with a mas ranging from 1.35 - 2.0 solar masses packed in a radius of about 12 km. The density of a magnetar is such that a spoonful of its substance, sometimes referred to as neutronium, would have a mass of over 100 million tons. They, as all stars have a spin and a magnetic field. Magnetars are special type of neutron stars that have very powerful magnetic field. The reason for their high energy magnetic field is that when the neutron star is formed, its spin , temperature and magnetic field fall into right angles, causing a dynamo mechanism to act, converting its heat and rotational energy into magnetic energy, increasing the magnetic field. The rotation speed of a magnetar is about 1-10 seconds per rotation. It is a tremendous flux density as compared to Earth's geomagnetic field. Scientific American describes the remarkable things happening in the magnetic field of a magnetar as-
"X-ray photons readily split in two or merge together. The vacuum itself is polarized, becoming strongly birefringent, like a calcite crystal. Atoms are deformed into long cylinders thinner than the quantum-relativistic wavelength of an electron."
Due to the decay of its strong magnetic fields, it emits large amounts of high energy electromagnetic radiations as X-rays and gamma rays. Consequently, it has a short active life span-of about 10,000 years.
"X-ray photons readily split in two or merge together. The vacuum itself is polarized, becoming strongly birefringent, like a calcite crystal. Atoms are deformed into long cylinders thinner than the quantum-relativistic wavelength of an electron."
Due to the decay of its strong magnetic fields, it emits large amounts of high energy electromagnetic radiations as X-rays and gamma rays. Consequently, it has a short active life span-of about 10,000 years.
It was first discovered on March 5,1979 when the two Soviet spacecrafts that were moving through the solar system were hit by a blast of gamma radiation which raised the radiation counts on both probes 2000 times. It was also felt by many other probes and was also recorded on Earth..It was 100 times more intense than any known extra-solar burst.The direction of the source corresponded with the remnants of a star that had gone supernova around 3000B.C.
Some known magnetars are:
Some known magnetars are:
1)SGR 1806-20
2)SGR 1900+14
3)SGR 0501+4516
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