This x-ray image of the Cassiopeia supernova remnant is the official first light image of the Chandra X-ray Observatory. Two shock waves are visible: a fast outer shock and a slower inner shock. The inner shock wave is believed to be due to the collision of the ejecta from the supernova explosion with a circumstellar shell of material, heating it to a temperature of ten million degrees. The bright object near the center may be the long sought neutron star or black hole that remained after the explosionthat produced Cassiopeia A. NASA's new $1 billion X-ray telescope is performing as expected, space agency officials and scientists said Thursday, Aug. 26, 1999. (AP Photo/Chandra X-ray Center & NASA)