The Count of Every Atom

Scientists estimate there are 10 to the power of 80 protons in the entire observable universe. This staggering figure is known as the Eddington number, representing nearly every building block of matter we can see.

Calculating the total number of protons is a massive challenge in astrophysics. While Arthur Eddington first arrived at this number through complex mathematical theories, modern observations have largely confirmed his ballpark estimate. It is mind-bending to realize that every star, planet, and galaxy is composed of these same particles. This number serves as a fundamental benchmark for understanding the vast scale of our cosmos.