The Expanding Universe
The Sky at Night · Season 69 · Episode 6
The team explores one of the greatest discoveries of modern astronomy - that our universe is expanding - and the new questions it raises about how the cosmos works. In the 1920s, astronomers studying galaxies realised they were moving away from us, with the most distant ones receding the fastest. The conclusion was revolutionary: space itself was stretching, and the universe was expanding in every direction. But once this discovery was made, a new challenge emerged – how fast is the universe expanding, and what could that tell us about its age, size and ultimate fate?
Episode Details
Air date, runtime, timezone, and episode position.
Season
69
Episode
6
Air Date
08/Sep/2025
Air Time
22:00
Runtime
29 min
Overview
Episode summary.
The team explores one of the greatest discoveries of modern astronomy - that our universe is expanding - and the new questions it raises about how the cosmos works. In the 1920s, astronomers studying galaxies realised they were moving away from us, with the most distant ones receding the fastest. The conclusion was revolutionary: space itself was stretching, and the universe was expanding in every direction. But once this discovery was made, a new challenge emerged – how fast is the universe expanding, and what could that tell us about its age, size and ultimate fate?
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