Lawrence Berkeley National Laboratory
Berkeley Lab: Nuclear Energy: Fission/fusion
Provides a definition and explanation of fission, the splitting of a heavy nucleus into two roughly equal parts, and fusion, the process where two nuclei combine together to form a larger nucleus.
Lawrence Berkeley National Laboratory
Berkeley Lab: Four Fundamental Interactions
Discussion of the four fundamental forces of nature: strong interactions, weak interactions, gravity, and electromagnetism.
Lawrence Berkeley National Laboratory
Berkeley Lab: Other Stars
Describes other stars besides the sun in our galaxy and the major stages in the evolution of a massive star.