The Sun

THE SUN 
The sun is the most significant star for the existence and life of living beings on earth. The whole life on earth depends on this brightest object in the sky. The living things get their energy from sun and the appropriate distance of earth from sun maintains an  appropriate temperature which is ideal for the survival of all the life present on earth. 
The sun is the principle source of energy for all the planets of the solar systems .Through a
constant stream of particles that flow outward from the sun, heat, radiation, light and UV rays are emitted.the UV rays that reach the earth from sun are considered to be the most harmful ones.Most of the UV and other high energy radiation are absorbed by the Ozone layer and the atmosphere of the earth.This stream of particles is called solar wind. 
STRUCTURE OF THE SUN
The visible surface of the sun is called photosphere which is a turbulent region and is 570 kilometer deep. 
The layer outside the photosphere is chromospheres which is a broad layer and is several miles thick. The outside layer of the sun is corona. Energy released by the sun passes from chromospheres to the corona and then to the outer space.