What is the heaviest element a star produces before it goes nova or supernova?
Lead (Pb): “The main component [of the S-process] produces heavy elements beyond Sr and Y, and up to Pb in the lowest metallicity stars.” 1) “Stellar nucleosynthesis occurs in stars during the process of stellar evolution. It is responsible for the generation of elements from carbon to iron by nuclear fusion processes. Stars are the nuclear furnaces in which H and He are fused into heavier nuclei, a process which occurs by proton-proton chain in stars cooler than the Sun, and by the CNO cycle in stars more massive than the Sun. Of particular importance is carbon, because its formation from He is a bottleneck in the entire process. Carbon is produced by the triple-alpha process in all stars. Carbon is also the main element used in the production of free neutrons within the stars, giving rise to the s process which involves the slow absorption of neutrons to produce elements heavier than iron and nickel (57Fe and 62Ni). Carbon and other elements formed by this process are also fundamenta
According to Wikipedia (and this matches my recollection from other sources), Iron is the heaviest element that can be produced by conventional nuclear fusion in stellar cores. http://en.wikipedia.
