Observationally CEEs should be brighter than typical novae but fainter than typical supernovae. These combine to provide fundamental distance estimates to supernovae in other galaxies. Resolution of these uncertainties requires the analysis of more supernovae and supernova remnants. Ic supernova, to some of the most luminous supernovae known such as SN 1999as. Such electrons are produced in supernovae and active galactic nuclei. Observation and discovery of extragalactic supernovae are now far more common. In 1998, the High-Z Supernova Search Team published observations of Type Ia ("one-A") supernovae. Therein the antimatter forms a wind which crashes upon the ejecta of the progenitor supernovae. The first recorded observations of comets and supernovae were made in China. Ia supernovae resulting from merging white dwarfs. These explosions are rare, perhaps about one per 100,000 supernovae. Especially energetic supernovae could be the source of these bursts. The nitrates were apparently formed from nitrogen oxides created by gamma rays from the supernovae. This provides a confirmation to cosmic acceleration independent of supernovae. Massive stars like Antares are expected to explode as supernovae.