If you've spent any time perusing the periodic table of elements, you've probably noticed that there aren't too many gaps. As the chart progresses, the number of protons, which define an element, march neatly from 1 to 2 to 3 and so on. This orderly transformation can't be made by fusion in stars alone. If you've ever enjoyed lithium, gold, or our entire physical universe, you have a phenomenon called neutron capture to thank. Here's why.
Source: io9. Read full article. (link)