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.

Look around you (or, if you’re sight impaired, touch something). Everything solid, liquid, or gas that you see and feel is made of matter. We sometimes call it “normal” matter, though with dark matter ...

The proton, one of the building blocks for all matter, has a variable size depending on how you look at it. If you are looking at its charge, it will have one radius, but if you look at its mass, you ...

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 ...