There are two main types of nucleosynthesis: Big Bang nucleosynthesis and stellar nucleosynthesis. Big Bang nucleosynthesis occurred in the early universe, shortly after the Big Bang. During Big Bang nucleosynthesis, the lightest elements, such as hydrogen and helium, were created. Stellar nucleosynthesis occurs inside stars. In stars, heavier elements are created through a process called nuclear fusion.
Cerium is produced through stellar nucleosynthesis. It is created when two neutrons are captured by a nucleus of neodymium. Neodymium is a rare earth element that is found in larger amounts than cerium. When two neutrons are captured by a nucleus of neodymium, the nucleus becomes unstable and emits a beta particle. A beta particle is a high-energy electron. When the beta particle is emitted, the nucleus of neodymium becomes a nucleus of cerium.
The amount of cerium that is produced in a star depends on the size of the star and the temperature of the star's core. Smaller stars produce less cerium than larger stars. Hotter stars produce more cerium than cooler stars.
Cerium is also produced in supernovae. Supernovae are the explosions that occur when massive stars die. During a supernova, a large amount of energy is released. This energy can cause the nuclei of atoms to fuse together to form heavier elements. Cerium is one of the elements that can be produced in a supernova.
The cerium that is found in the Earth's crust is thought to have come from two sources. Some of the cerium came from the interstellar medium. The interstellar medium is the gas and dust that exists between stars. Some of the cerium also came from supernovae.
