From Discovery News:
Astronomers have just solved a decade-old mystery that explains the unusual behavior of a neutron star -- the dense, hot corpse left behind after a massive stellar explosion -- at the center of the Cassiopeia A supernova remnant.
It wasn't the X-rays streaming from the center of the supernova remnant that astronomers found puzzling. It's why the beams weren't pulsating as expected. Now the scientists know why: The neutron star is covered with a thin atmosphere of carbon, which acts like a giant bulb to smooth light in all directions.
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