The sun is the center of our solar system. Its surface, or photosphere, is made of tiny granules or small cells of matter packed close together which is not always even. Each granule lasts about 8 minutes and is about 600 miles across. Also on the surface are sunspots. Between these sunspots are dark ribbons, or filaments, called prominences.
Of course, the sun has a core which is 150 times as dense as water. The pressure on the surface of the core is equal to 250 million atmospheres. Nuclear reactions turn hydrogen into helium. This is what brings the sun's life-bringing glow. The sun contains 98 percent of all the rocks, dust, and gas in the solar system. Many other gases that the sun contains are carbon, nitrogen, and small amounts of other gases.
The middle layer of the sun moves up then down in a circular motion. It goes first deeper into the sun and then back out again. This churning also ejects huge streams of gas known as solar flares. The atmosphere is actually hotter than the surface. The corona extends far into space but is only visible during a solar eclipse.
