Did Gold Come from a Supernova?
Gold is the ultimate recyclable product on Earth. Gold is a metal which is a pure element. It has an atomic number of 79, making it one of the heaviest naturally-occurring metals. It is soft, heavy, and yellow in color. Gold has a number of properties which make it ideal for making jewelry: it looks nice, it is soft, ductile, malleable, and it doesn’t tarnish.
Gold has been used for jewelry since metals were first discovered about 6,500 years ago. Jewelry you are wearing today might be made from gold jewelry found in ancient Egypt. It also has been used for centuries in coins, statues, and industry. It’s valuable! Don’t throw it away. Recycle it by selling it, or keep it.
But where did Gold come from? While “gold mines” would not be an incorrect answer, this blog post addresses the bigger picture.
It is the commonly-held conclusion among scientists and astronomers that gold came from a neutron-rich supernova that exploded and formed our solar system, scattering the neutron-rich heavy element gold throughout the galaxy. Let me explain how this works.
A supernova is basically an exploding star. After a few million years of generating energy by fusing light elements into heavier ones (hydrogen to helium, helium to carbon, and so on), the core runs out of fuel. Iron builds up in the very center of the star, and no star in the Universe has what it takes to fuse iron. At some point, so much iron builds up that it cannot support its own weight, and the ball of iron collapses.
A Type II supernova results from the death of a single star much more massive than the sun. When such a star begins to burn out, its core quickly collapses. Tremendous energy is suddenly released in the form of neutrinos (a type of subatomic particle) and electromagnetic radiation (electric and magnetic energy). This energy causes the star to erupt into a supernova.
Supernovae can also leave behind different types of objects. After some supernova explosions, there remains a small, dense star composed mainly of neutrons or perhaps of elementary particles called quarks. Such a star is called a neutron star. Rapidly-rotating, highly-magnetized neutron stars are called pulsars. After other explosions, an invisible object called a black hole may be left behind. A black hole has such powerful gravitational force that not even light can escape it. In some cases, no object of any kind remains after a supernova explosion.
Scientists believe that supernovae created all the heavier elements, such as iron, gold, and uranium, that are found on earth and have been detected in objects outside the solar system. Also, there is evidence that some high-energy cosmic rays originate in supernovae.