Cosmic Rays: High-Energy Visitors from Space

Cosmic rays are high-energy particles, mostly protons, that travel through space at near-light speeds.
They were first discovered in 1912 when Victor Hess measured radiation high above Earth.
Most cosmic rays come from outside our Solar System, and some from distant galaxies.
Supernova explosions are major sources, blasting particles across the cosmos.
The most energetic cosmic rays carry more punch than a fast-pitched baseball packed into a single particle.
When cosmic rays hit Earth’s atmosphere, they create showers of secondary particles.
These particle showers can be detected by ground-based observatories.
Cosmic rays can pose risks to astronauts and spacecraft electronics.
Studying them helps scientists learn about extreme environments like black holes and neutron stars.
Despite a century of research, the origins of the highest-energy cosmic rays remain a mystery.