Energy from the Sun—in the form of isolation from sunlight—supports almost all life on Earth via photosynthesis, and drives the Earth's climate and weather. The Sun, our Sun is the ONLY source of light, Energy, Life and Heat that The Earth uses.Mar 19, 2007

The Sun is the star at the center of the Solar System. The Earth and other matter (including other planets, asteroids, meteoroids, comets and dust) orbit the Sun, which by itself accounts for more than 99% of the solar system's massThe star around which the Earth revolves, and the planet's source of light and heat, hence life

The sun is a star, just like the other stars we see at night. The difference is distance -- the other stars we see are light-years away, while our sun is only about 8 light minutes away -- many thousands of times closer.

The core starts from the center and extends outward to encompass 25 percent of the sun's radius. Its temperature is greater than 15 million degrees Kelvin [source: Montana]. At the core, gravity pulls all of the mass inward and creates an intense pressure. The pressure is high enough to force atoms of hydrogen to come together in nuclear fusion reactions -- something we try to emulate here on Earth. Two atoms of hydrogen are combined to create helium-4 and energy in several steps: