The Expansion Asymmetry and Age of the Cassiopeia A Supernova Remnant
The Expansion Asymmetry and Age of the Cassiopeia A Supernova Remnant
HST images of the young supernova remnant Cas A are used to explore the expansion and spatial distribution of its highest velocity debris. ACS WFC images taken in 2004 March and December with Sloan F625W, F775W, and F850LP filters were used to identify 1825 high-velocity, outlying ejecta knots through measured …