The remaining one percent is a mixture of oxygen, carbon, iron, neon, nitrogen and other trace elements. The sun is by far the largest object in the solar system, containing 99.9% of all the matter in the solar system - the sun is 870,000 miles in diameter, and one million Earths could fit inside the sun.
The temperature of the sun reaches 22.5 million degrees Fahrenheit in its interior, and around 10,000 degrees Fahrenheit at the surface. Periodically, regions of the surface cool to 6,000-7,000 degrees Fahrenheit (UCAR, 2006). These appear as dark spots on the sun's surface, and are called sunspots (Arnett, 2005). These can be as much as 30,000 miles in diameter, and are caused by magnetic interactions that are not well understood. At areas near sunspots, sudden increases in brightness often occur (UCAR, 2006). These are called solar flares, and are caused by an increase in the rate of energy release.
The sun releases energy at a rate of 386 billion billion megawatts per second (Arnett, 2005). In the interior, around 700,000,000 tons of hydrogen is converted to helium and energy per second. As this energy travels to the sun's surface it cools to surface temperature.
The star we call the sun is at least 4.5 billion years old (SSC, 2006). It is believed that the formation of the solar system was initiated by a nearby supernova (UCAR, 2006). A supernova occurs when a very large star explodes. When this happens, shockwaves and matter forced from the dying star can cause the creation of new stars. In the case of our solar system, scientists believe that a supernova may have disturbed a dense cloud of gases and dust, which was compressed by shockwaves, and then began to collapse due to gravitational forces that pulled the dust and gases together.
As the cloud collapsed in on itself, it began to spin (UCAR, 2006). It grew hotter and denser in the interior, with a cooler disc of gas and dust surrounding it. As it continued to spin, the disc grew thinner, and particles began to clump together. Planets and moons were formed as the clumps in the disc merged and grew bigger, and as the cloud continued to collapse, the center grew so hot that it became a star. This is our sun.
Since the birth of the solar system, the sun has used up about half of the hydrogen that was once present (Arnett, 2005). It is estimated that another five billion years will pass before the sun has exhausted its supply of hydrogen. When this happens, the sun will gradually turn into a type of star called a red giant (UCAR, 2006), which is simply a star which has used up all its hydrogen and is using helium or other elements as fuel. When this happens, the sun will expand in size to engulf the inner planets - Mercury, Venus, Earth, and Mars will all be destroyed.
The Sun in Mythology
Because the sun is so vital to life on Earth, and a prominent feature of the sky, it was natural for early civilizations to develop myths detailing the creation of the sun. For example, in the mythology of various North American Indian tribes, the sun was found or created by deities (Olcott, 1914, p3) - according to Yuma Indian legend, the god Tuchaipa created the Earth and moon (Olcott, 1914, p4), but then realized that man would need brighter light, and so created the sun. The Yokut