Cosmic ray
Videos
Cosmic rays or astroparticles are high-energy particles or clusters of particles that move through space at nearly the speed of light. They originate from outside the Solar System — from the Milky Way
Pacini makes a measurement in 1910.
Increase of ionization with altitude as measured by Hess in 1912 (left) and by Kolhörster (right)
Hess lands after his balloon flight in 1912.
Sources of ionizing radiation in interplanetary space.
Air shower (physics)
Videos
Air showers are extensive cascades of subatomic particles and ionized nuclei, produced in the atmosphere when a primary cosmic ray enters the atmosphere. Particles of cosmic radiation can be protons,
Cosmic ray air shower created by a 1 TeV proton hitting the atmosphere 20 km above the Earth. The shower was simulated using the AIRES package. Animated 3D models of this and other showers can be found on COSMUS.
Sketch of the hadronic and electromagnetic sub-cascades in an air shower.
Number of particles for different primary energies as a function of the surpassed atmospheric depth.