The World’s Largest Exhibition

And the humbling lesson it imparts about our place in the universe

Image by Richard Allen

In Ithaca, New York, there is a display called the Sagan Planet Walk, named in honor of astrophysicist Carl Sagan. It is an interactive exhibit in which the solar system is scaled at one five billionths of its actual size. The sun is about the size of a basketball, and the planets and their distance from the sun are also to scale. You can walk…