Protons are tiny particles just a femtometer across, but without them, atoms wouldn't exist. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

Mrs Roberts: What do you think you're made of? Mr Spellman: Big question. Grit, determination, hard-working, handsome, charming, funny. Mrs Roberts: Well, I guess. But you're actually made of atoms.

OAK RIDGE, Tenn. — Examining the smallest parts of the universe often takes the biggest kinds of equipment. At Oak Ridge National Laboratory, a unique piece of equipment the size of a building is ...