Insolation and Heat Budget

The sun is the primary source of heat to the earth and its atmosphere. The heat received from other celestial bodies as well as the interior of the earth is rather too insignificant to merit our attention. Even the atomic energy released through the disintegration of radioactive elements present in the earth's crust is not of any consequence from the viewpoint of weather and climate. Thus, radiation from the sun is the only a source of energy for the atmosphere, the oceans and various life forms on earth. Such factors as the distance of the earth and the sun, the nature of the atmosphere, rotation of the earth on its axis, and its revolution around the sun affect the amount of radiant energy that our planet receives from the sun.

 Its is rather staggering to our imagination to think of the distance that scparates the earth from its parent body, the sun. It averages about 149,000,000 kilometers. With a volume over a million times of the earth and diameter more than one hundred times the earth's, The sun's size and distance defy all our comprehensions. Imagine that even a jet flying at the speed of 800 kilometers per hour would require more than two decades to take a man to the sun. No less astonishing is the fact that even the roys of the sun we see as light take about 8 minutes to reach the earth's surface.

The diameter of the sun measures roughly about 13,82,400 kilometers. The mass of the sun is about 3,32,000 times that of the earth. average density of the earth is 5.52, while that of the sun is 1.41. As we know, the sun is a self - luminous mass of extremely hot gases that emits radiant energy that caters to the energy need of all the planets and their satellites within the solar system. The energy radiated from the sun is the result of a nuclear reaction taking place in its interior. There hydrogen is changed into helium through nuclear fusion. The surface temperature of the sun is estimated between 5500 Degree C and 6100 Degree C , In addition to the radiant energy, the sun also emits corpuscular energy which affects the magnetic field surrounding the earth. Their effects on the earth's magnetosphere can be seen in the aurora lights produced near the poles. 
 video reference : https://youtu.be/FYheqR5R3QI