Pictures taken from:
http://www.bearwoodphysics.com/ background1.htm
http://solid13.tphys.physik.uni-tuebingen.de/muether/kick/kern-tick.html
http://www.spacescapes.com/
http://members.tripod.com/~mrbeens/atom.html
Google
http://homer.hcrhs.k12.nj.us/sol/chemistry/ past_stoich.html
