Neutron-star collisions may be source of gold and other heavy elements

Washington Post : Until recently it was thought that heavy elements, such as gold, platinum, lead, and uranium, were only formed by supernova explosions. But new evidence also points to neutron-star collisions. On 3 June NASA’s Swift space telescope detected a short gamma-ray burst in a galaxy almost 4 billion light-years away. Subsequent observations by the twin Chile-based Magellan telescopes and the Hubble Space Telescope revealed the radioactive afterglow caused by the formation of a large number of heavy atoms. The direct observation of such a large, brief explosion led astronomers to believe it was caused by the merging of two neutron stars, which would have the number of neutrons needed to drive the formation of heavier elements. Those elements are merely dust in the interstellar wind, however, until over billions of years, gravitational forces pull the material together to form planets and stars.