Andromeda Is the Last Galaxy We Will Ever Be Able to Visit

Right now, at about one hundred and ten kilometres every second, a galaxy is falling toward this one. Three and a half billion kilometres of separation erased every year. In this calming long-form space documentary we price the trip in real hardware: Voyager 1, one light-day out after fifty years. Slipher's 1912 spectrum, Leavitt's Cepheids, Hubble's 1923 plate, the 2.7-kelvin hiss Penzias and Wilson found by accident. Nineteen galaxies in twenty already sit past the cosmological event horizon, 16.5 billion light-years out, and cannot be reached. Nothing here needs reaching for. The night sky is quieter than it looks, and settled. Play it low, and rest easy.