Saturn is the crown jewel of the solar system, beautiful and fascinating. It is a gas giant, and has a broad set of rings made of ice particles. Moons create gaps in the rings via their gravity. Saturn has dozens of moons, including Titan, which is as big as Mercury and has a thick atmosphere and lakes of methane; and Enceladus which has an undersurface ocean and eruptions of water geysers. While we are still uncertain, it is entirely possible that either or both moons may support life.
Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into helium over a trillion years. More massive stars like the Sun live shorter lives. They fuse hydrogen into helium, and eventually helium into carbon (and also some oxygen and neon). When this happens they expand, get brighter, and cool off, becoming red giants. They lose most of their mass, exposing their cores, and then cool off over many billions of years.
Neil deGrasse Tyson sets off on the Ship of the Imagination to chase a single comet through its million-year plunge toward Sol. Later, Tyson visits the birth-place of Sir Isaac Newton and retraces the unlikely friendship between Newton and brilliant polymath Edmond Halley. It was Halley's patience and generosity which allowed Newton to conquer his fear of isolation and find the courage to publish his masterwork, "Principia Mathematica" which launched a scientific revolution.
If a massive asteroid collides with earth, it could end life on our planet as we know it; new discoveries and cutting-edge tech reveal just how close we are to apocalypse and what it would take for the world's leading space agencies to stop it.