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.

The “lead” of a pencil is actually made of a substance called graphite which is made of carbon atoms. The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and ...

Discover the fascinating world of particle physics — the most fundamental building blocks of the universe and the forces that connect them. When you purchase through links on our site, we may earn an ...