'Ageless' silicon may indicate a well-mixed galaxy
When massive first-generation stars in young galaxies end their lives as violent supernovas, they fill the cosmos with so-called primary isotopes--elements like oxygen, carbon and silicon with a balance of neutrons and protons in their nuclei. Since there is a greater concentration of stars the closer you get to the center of the Milky Way, including massive stars that end their lives as supernovas, astronomers expect to find a greater percentage of heavier isotopes among the elements there. This survey may indicate that the Milky Way is remarkably efficient at mixing its material, circulating molecules and atoms from the galactic center out into the galaxy’s spiral arms and back.
Provided by Green Bank Observatory