Eric Walker added We Now Have Proof a Supernova Exploded Perilously Close to Earth 2.5 Million Years Ago to Supernovae, 53Mn and 60Fe
Eric Walker added We Now Have Proof a Supernova Exploded Perilously Close to Earth 2.5 Million Years Ago to 60Fe, and added 60Fe to Iron
Eric Walker added a number of topics and a number of links to Iron, and added Iron to Metals and Chemical elements