One light year is the distance light travels in a single year, a little under 6 trillion miles, and the Milky Way is about 100,000 light years across. The speed of light behind that distance has been fixed exactly by international agreement since 1983, at a little over 186,000 miles every second. A passenger jet flying day and night without ever landing would need well over 1 million years to cross a single light year. The usual picture of a light year as the first short tick on an astronomer's ruler leaves out almost everything that lies along it. This is what traveling one light year would actually involve, crossed slowly, one light second, one light day and one light month at a time.

Here at Sleeping Cosmos, we build long-form space documentaries for quiet hours. The pace is slow on purpose. Nothing rushes, nothing shouts, and nothing asks you to keep up. Just one idea settling into the next, out through the solar system and into the quiet parts of the sky that most people never think about.

Good for: 😴 Falling asleep — steady narration and long, unhurried stretches of the cosmos 📖 Reading or studying — calm pacing and clear explanations that sit in the background 🌘 Winding down — for anyone who likes the big questions asked gently

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