Skip to main content
Back to Show
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?

Support Provided By
Where Are We?
Unlock with PBS Passport
54:11
Can three volunteers measure the solar system and universe to find out where we are?
What Are We?
Unlock with PBS Passport
54:41
Three volunteers set out to find an amazing realization about the nature of life itself.
Where Did the Universe Come From?
Unlock with PBS Passport
54:41
The group experiments with cars and balloons to understand the origin of the universe.
Why Are We Here?
Unlock with PBS Passport
54:41
The volunteers pose an important question about our role in the universe.
Are We Alone?
Unlock with PBS Passport
54:41
Three volunteers set to find out how likely it is that aliens exist.
Can We Time Travel?
Unlock with PBS Passport
54:40
Stephen Hawking sets three challenges to find out if we could be time travelers.
Active loading indicator