Most stars, like the Sun, are made of different layers of hot gas. As the stars rotate, the layers spin at different rates. That tangles up a star's magnetic field, creating big magnetic storms on its surface. And when the field gets too tangled, it triggers powerful explosions.
But in a neutron star, the tangled magnetic fields can crack the star's solid crust, triggering outbursts that are far more powerful than those from any Sun-like star.
Neutron stars are the crushed remnants of exploded stars. They're as massive as the Sun, but only a few miles in diameter. They're squeezed so tightly that they have a solid crust, with a "liquid" layer of pure neutrons below.
Some neutron stars spin rapidly -- once every few seconds, or even faster. They "beam" energy into space from their magnetic poles. If Earth lies along the path of one of these beams, we see the star "pulse" on and off, like a lighthouse beacon sweeping across the cosmic landscape.
Over time, these pulsars spin a little slower. But some of them can suddenly speed up again.
That's probably caused by the different spin rates of the solid crust and the liquid layer below. This generates extremely powerful magnetic fields. When the fields get tangled, they produce "starquakes" in the crust -- violent cracks that are accompanied by enormous bursts of energy. The crust then catches up to the liquid layers below it -- starting the cycle all over again.
Script by Damond Benningfield, Copyright 2007
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