Cosmic radiation refers to high-energy particles that originate from outer space and travel through the universe. These particles can include protons, electrons, and atomic nuclei, and they constantly bombard the Earth. Most of this radiation is absorbed by the Earth's atmosphere, but some particles reach the surface, contributing to background radiation levels. The primary sources of cosmic radiation are events like supernovae and the sun. While cosmic radiation is a natural phenomenon, it can pose health risks to astronauts and high-altitude pilots due to increased exposure. Understanding cosmic radiation is essential for space exploration and protecting human health in these environments.