In this clip from Genius by Stephen Hawking, the volunteers embark on an experiment to visualize how many stars are in our galaxy. Galileo played an important role in helping to quantify our galaxy. He took a technology developed for navigation at sea and turned it to the skies. His telescope revealed that the Milky Way is made out of stars, it is so vast it is only possible to estimate how many stars exist in it. Stephen Hawking has set a task for the volunteers to visualize how many stars are in the universe, and therefore the likeliness of other life in space. Each potential star in space could be another potential energy source for life. Using sand, they work with the concept one grain of sand is equal to one star and work to create a visual representation of the number of stars in our galaxy.