Question

what is cosmic ray?​

Answer 1

Answer:

A highly energetic atomic nucleus or other particle travelling through space at a speed approaching that of light.

Answer 2

Answer:

$\huge\red\star{HEYA!}$

Showers of high energy particles occur when energetic cosmic rays strike the top of the Earth's atmosphere. Most cosmic rays are atomic nuclei: most are hydrogen nuclei, some are helium nuclei, and the rest heavier elements. ... Cosmic rays are atom fragments that rain down on the Earth from outside of the solar system.