What Would Actually Happen If You Traveled 100 Light-Years?

Tonight, follow a hypothetical journey one hundred light-years from Earth and back. With an ideal ship accelerating at one gravity and braking to rest, about eighteen years aboard could span more than two centuries at home. Explore the clock calculations, interstellar gas and dust, life aboard, changing constellations, Earth’s faint light and the long journey of every message. Discover why the report sent at the distant arrival could reach Earth only about two years before the returning crew. This calm space journey is a physics thought experiment, far beyond current spacecraft engineering.