Are There Really as Many Neurons in the Human Brain as Stars in the Milky Way?
This is a phrase a lot of science communicators like to use because giving people a sense of scale when it comes to large numbers is so difficult. That’s why journalists report distances as number of football fields, mass as number of fully-loaded 747s, energy in terms of Hiroshima bombs, etc.
Even though we can’t conceive of the number of stars in the Milky Way or the number of neurons in the human brain, equating the two gives people a sense of enormity. And as conscious beings we like to find patterns, and we find equivalencies interesting, especially when the things being equated are “important” or “epic” (like neurons and stars).