Cosmic Rays

From ExoDictionary
Jump to: navigation, search
This definition page has been automatically generated.
You can help ExoDictionary by expanding, updating, or correcting it.

This autostub has not yet had its initial copyediting proof and may contain significant formatting and even factual errors. You can improve Exodictionary by cleaning up the page markup and verifying that the definition is correct and then removing this tag.

This autostub has not yet had its initial categorization proof and may be categorized incorrectly. You can improve Exodictionary by removing inappropriate categories and then removing this tag.

Cosmic Rays

The aggregate of extremely high energy subatomic particles which travel the solar system and bombard the earth from all directions. Cosmic-ray primaries seem to be mostly protons, hydrogen nuclei, but also contain heavier nuclei. On colliding with atmospheric particles they produce many different kinds of lower energy secondary cosmic radiation (see cascade shower). Also called cosmic radiation.
Cosmic rays thought to originate outside the solar system are called galactic cosmic rays. Those thought to originate in the sun are called solar cosmic rays.
In the earth's atmosphere, the maximum flux of cosmic rays, both primary and secondary, is at an altitude of 20 km, and below this the absorption of the atmosphere reduces the flux, though the rays are still readily detectable at sea level. Intensity of cosmic-ray showers has also been observed to vary with latitude, being more intense at the poles. See cosmic-ray knee, corpuscular cosmic rays.


This article is based on NASA's Dictionary of Technical Terms for Aerospace Use