The Crab Nebula
(Credit: S. L. Snowden USRA, NASA/GSFC)
Both the Crab Nebula and Crab pulsar are clearly visible in this HRI image. The supernova precursor to these objects was observed and recorded by Chinese astronomers in the year 1054. Although visible in Europe at the same time, it was not recorded in any surviving document.
The pulsar (the bright compact emission) produces highly relativistic electrons which themselves produce synchrotron radiation in the magnetic field of the nebula.
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