Sciencespeaking topic
The night sky is dark. But if the universe is infinite and full of stars, then in every direction you look you should hit a star and the sky should be blindingly bright. What does the dark sky actually tell us about the universe?
— Olbers' paradox
practice with this topic
Set the timer (5-30 min), take 20 seconds of prep if you like, start talking. Jot your thoughts onto the sticky-note board.
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