There may not be a pot of gold at the end of the rainbow, but you might be able to find one at the site of a collapsing star.
Scientists have long pondered the origin of elements like gold and platinum. Lighter elements (fewer protons in their nucleus) like carbon and iron are made in the center of stars and then spewed out during a supernova, the explosion at the end of a star’s life. However, the inside environment of stars is not right for producing heavier elements such as gold. Scientists did observe what appeared to be the creation of these heavy elements during the collision of two neutron stars (dense, dead stars that are left behind after a supernova), and thought that maybe these powerful crashes were responsible for creating elements like gold. But there were some problems with this theory; the creation of neutron stars and their subsequent collisions take a long time to happen, and heavy elements can be found in very, very old stars that formed early in the history of the universe. So would there have been enough time for neutron star collisions to have produced the elements, or was something else responsible?
But now, scientists think they have found a better explanation than neutron stars. When massive stars, aptly named “collapsars,” reach the end of their lives, their cores collapse into black holes while their outer layers are shot out in a very rare type of supernova. The new black hole is left surrounded by a ring of debris that is believed to be the perfect environment for producing heavy elements. And the best part is that these sorts of collapses began happening early in the universe’s history and could produce far more heavy elements than a neutron star collision. One explosion could produce an amount of gold 100’s of times the mass of the earth! The researchers think that these types of supernovas account for 80% of the heavy metals in the universe, with neutron star collisions accounting for the remaining 20%. So next time you look in your jewelry box, think about the absolutely incredible explosion that created the materials you now get to wear!
Want to learn more? Visit https://www.sciencenews.org/article/dying-stars-called-collapsars-may-forge-much-universe-gold
May 19, 2019