WHAT ARE COSMIC RAYS ?

This photo of the remains of Supernova 1987A was taken by Hubble Space Telescope 7 years after the star exploded.

Cosmic rays are high energy particles from outer space.

About 1000 cosmic rays per second strike each square meter area of Earth's atmosphere.

Cosmic rays are produced in our Galaxy by supernova explosions and by objects such as neutron stars and black holes. Cosmic rays are also produced by the Sun during violent events called coronal mass ejections.

About 90 % of Galactic cosmic rays are protons, 9 % are helium nuclei, and the rest are nuclei of heavier atoms.

Sequence of SOHO images showing a coronal mass ejection (CME) exploding outward from the Sun.


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