cassiopeia
The Cassiopeia A supernova remnant observed in X-rays by the Chandra X-ray observatory. This remnant is about 300 years old. Cassiopeia A is located about 10,000 light years from earth and the size of the remnant is about 10 light years across. The bright dot in the center of the remnant is the neutron star formed during the supernova explosion.
Operation of NSCL as a national user facility is supported by the Experimental Nuclear Physics Program of the U.S. National Science Foundation.