The Ancient Collision That Everyone Saw

The year is 1987, and on February 23rd, three separate neutrino observatories experienced a huge burst in detections. Although initially unsure of their origin, the next day a Supernova was discovered in the Large Magellanic Cloud, a small satellite galaxy of the Milky Way visible in the southern hemisphere.  Known as 1987A, it was the closest supernova observed in centuries, and was observed by astronomers around the world as it brightened and then slowly dimmed.  By combining the visible observations with the neutrino data, scientists learned about how supernovae occur, constrained the mass of the neutrino, and opened a new...

Where does the Gold come from?

Gold doesn’t come from your local jewelry store, and the Gold rush that occurred in the Yukon territory at the turn of the 20th century is not the source I’m talking about either.  I want to take it further back, to the origins of gold the element.  Similar to the origins of most other elements on the periodic table, it requires an immense amount of energy, such as the nuclear fusion that goes on within a star.  But Gold can not be made by a star’s thermonuclear engine.  Gold requires more energy, as does every other element heavier than Iron.  So...