Our ship docked in Halong Bay, and I've had a lot of recent coverage because of our  Diamond Princess cruise through this area , so I will today focus on Fusion, the greatest hope for sustainable energy into the long-term future,  Today, only a history. There are two kinds of nuclear reactions. Fission:  splitting a heavy nuclei, like Uranium.  An Atomic Bomb gets energy from fission. Fusion:  joining light nuclei, like, like isotopes of Hydrogen, Deuterium and Tritium.  A Hydrogen Bomb uses fusion. Some  fusion history . In 1920, British physicist Francis Aston discovered that the mass of four hydrogen atoms is greater than the mass of one helium atom, which implied that energy can be released by combing hydrogen atoms to form helium. This concept provided the first hints of how stars produced energy. Henry Russell observed that a star's heat came from a hot core rather than the entire star. Mark Oliphant, working with Ernest Rutherford and oth...