Back to today’s briefing

Story perspectives

Today in History: First Evidence of Quarks Discovered at SLAC

10/20/2025

50 8

Summary

Story summary

On October 20, 1968, researchers at the Stanford Linear Accelerator Center published groundbreaking results revealing that protons are made up of smaller particles called quarks. This discovery provided the first evidence of quarks, fundamentally changing our understanding of atomic structure and the composition of matter.

1 of 1

Story summary

On October 20, 1968, researchers at the Stanford Linear Accelerator Center published groundbreaking results revealing that protons are made up of smaller particles called quarks. This discovery provided the first evidence of quarks, fundamentally changing our understanding of atomic structure and the composition of matter.