The word "galaxy" actually comes from the Greek word for "milk," galaxias! Ancient Greek myths said the Milky Way was formed when the goddess Hera spilled milk across the sky. When early astronomers saw the bright, misty band of stars stretching overhead, they thought it looked like a splash of milk — and the name stuck.
Later, as telescopes improved and more galaxies were discovered beyond our own, the term "galaxy" came to describe these massive star systems. Today, scientists believe there are over two trillion galaxies in the observable universe, each containing billions—or even trillions—of stars. A milky spill turned out to be a pretty fitting inspiration!