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Genius by Stephen Hawking
How Many Stars Are There in the Galaxy?
The volunteers are given a spoon of sand with 50,000 grains. Each grain of sand represents a single star. They try to guess how many stars there are in the galaxy and then use the spoon of sand to create a pile of stars with their estimate. How big will the pile of sand be and how close will it be to the actual number of stars in our galaxy?
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54:11
Can three volunteers measure the solar system and universe to find out where we are?

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54:41
Three volunteers set out to find an amazing realization about the nature of life itself.

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54:41
The group experiments with cars and balloons to understand the origin of the universe.

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54:41
The volunteers pose an important question about our role in the universe.

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54:41
Three volunteers set to find out how likely it is that aliens exist.
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54:40
Stephen Hawking sets three challenges to find out if we could be time travelers.