The Diary Of A CEO with Steven Bartlett

Snapshot · The Diary Of A CEO with Steven Bartlett

Neil deGrasse Tyson On Aliens, Simulation Theory, and What Happens Inside A Black Hole

Explore episode Jul 9, 2026

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How Far Could Humans Travel Across the Universe?

At 53:21 · chapter starts 52:07

One of the most clarifying numbers in the episode: New Horizons, the fastest human-made spacecraft, was designed to reach Pluto with the most powerful rockets available and the lightest possible payload. If instead directed at Alpha Centauri, our nearest stellar neighbour, it would take 50,000 years at those speeds. The implication is profound: space travel is not merely difficult, it may be practically impossible for biological entities within any reasonable timeframe. Tyson uses this to explain one of the leading responses to the Fermi paradox — maybe intelligent aliens exist everywhere, but space travel is simply too hard, so they haven't come. He also jokes that any aliens approaching Earth might have spotted the debris field of satellites surrounding us and simply turned around.

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