This short video on Cassiopeia A and the birth of the Solar System solves a mystery that has plagued science since 1975: Why was all Helium tagged with “strange” Xenon at the birth of the solar system?? http://www.omatumr.com/Data/1975Data.htm
The "strange" Xe-2 and "normal" Xe-1 in this figure represent the "two main components" of supernova debris seen in Cassiopeia A [DeLaney, T. et al., "The Three-Dimensional Structure of Cassiopeia A", Astrophysics Journal (submitted, 2010):
A. The outer layer, "probably made of helium and carbon", and
B. The inner layer made of heavier elements like "oxygen, neon, silicon, sulphur, argon and iron."
With kind regards,
Oliver K. Manuel