Stars

Our Sun is a main-sequence star of spectral type G2, which means it is a yellow dwarf star. As the Sun evolves and changes, it will have a significant impact on the planets in our solar system, including Earth. During the red giant phase, the increased luminosity of the Sun will cause the surface temperature of Earth to rise, making it uninhabitable for life as we know it. The entire process of the Sun's evolution from a main-sequence star to a white dwarf is expected to take about 10 billion years. This means that we are currently living in the middle of the Sun's life, and we have another 5 billion years or so before it starts to change significantly. Season 1, Episode 5: Stars Topics include: Sun Stars Astronomy Astrophysics Stellar evolution Fusion Nuclear reactions Solar system Solar flares Solar wind Corona Photosphere Chromosphere Solar eclipse Sunspots Stellar classification Black holes Supernovae Neutron stars White dwarfs Red giants Main sequence Nebulae Interstellar gas Cosmic dust Galaxies Milky Way Star clusters Exoplanets Habitable zone Extrasolar planets Planetary systems Hertzsprung-Russell diagram Luminosity Spectroscopy Infrared radiation Ultraviolet radiation