Here we learn how the Sun shines, and how long it will shine, as well as some of the great questions of 19th-century Physics. We'll also see what your smile looks like when you get a Nobel Prize. This is part of my intro Astronomy class taught at Willam Paterson University and CUNY Hunter. Jim Hutton's Siccar Point: Gravitational Potential Energy: Kelvin-Helmholtz mechanism: The discovery of radioactivity: Wilhelm Roentgen: Timeline of Nuclear Physics Discoveries: Einstein's Mass-Energy Equivalence: Sir Arthur Eddington: William Thomson, Lord Kelvin: Hermann von Helmholtz: Alpha Decay: Quantum Tunnelling: George Gamow: Gamow Peak: The Proton-Proton Chain: Tsar Bomba: Hans Bethe: Henri Becquerel: 0:00 Introduction 0:01 EXTRA DETAILS: How Do Stars Work? 1:45 How long can the Sun glow, shine, and emit light? 3:08 Sources of Energy (Internal Heat) in the 1800's 8:21 The Kelvin-Helmholtz Mechanism 10:40 The Kelvin-Helmholtz gravitational timescale 12:07 A Conflict of the Ages.... 13:22 Just for fun, what about a coal-powered Sun? 15:20 1896: Becquerel discovers radioactivity 18:36 1905: Einstein's Annus Mirabilis 19:27 1920: "The Internal Constitution of Stars" 23:15 Making them collide and stick is VERY tough... 25:42 1928: Gamow Discovers Quantum Tunneling 28:57 The Fusion Sweet Spot 36:02 The Proton-Proton Chain: Step 2 43:30 CNO Cycle: for hotter stars... 44:06 Age of the Sun: The Nuclear Timescale 45:06 Nature is Revealed to us Mere Mortals... 46:01 Energy Generation 46:34 Main Sequence Stars 46:46 Why Doesn't the Sun Explode? 47:35 Hydrostatic Thermostat 48:44 Summary.