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The '''Sun''' is a type G2V star; it is the star at the center of the solar system, and it accounts for over 99% of the mass of the solar system. By mass, it is composed of 72% hydrogen, 26% helium and 2% trace elements of oxygen, carbon, neon, nitrogen, magnesium, iron, and silicon.<ref>[http://www.nasa.gov/worldbook/sun_worldbook.html World Book Encyclopedia @ NASA]</ref> The eight planets, including Earth, orbit the sun, as do countless other small objects.  

The '''Sun''' is a type G2V star; it is the star at the center of the solar system, and it accounts for over 99% of the mass of the solar system. By mass, it is composed of 72% hydrogen, 26% helium and 2% trace elements of oxygen, carbon, neon, nitrogen, magnesium, iron, and silicon.<ref>[http://www.nasa.gov/worldbook/sun_worldbook.html World Book Encyclopedia @ NASA]</ref> The eight planets, including Earth, orbit the sun, as do countless other small objects.  

It provides the [[Earth]] with light and heat.  

It provides the [[Earth]] with light and heat.  

What eventually became the solar system initially existed as a large, rotating cloud of dust and gas, composed of hydrogen and helium produced in the Big Bang as well as small amounts of heavier elements. Around 4.57 billion years ago, the cloud began to contract, perhaps as a result of a shock wave from a nearby supernova. Inertia caused the rotating cloud to flatten into a disk. Most of the mass concentrated in the middle, and began to heat up. Eventually, the kinetic energy of the hydrogen was sufficient to overcome the electromagnetic repulsion between the protons, and fusion began. The resulting solar wind helped clear away much of the material which had not coalesced into planets or other orbiting bodies. <ref>[http://www.tufts.edu/as/wright_center/cosmic_evolution/docs/text/text_plan_1.html]</ref>. The sun is most likely a third-generation star. In Christian theology, [[God]] created the sun on the third day of [[Creation]]. <ref>Genesis 1</ref>

What eventually became the solar system initially existed as a large, rotating cloud of dust and gas, composed of hydrogen and helium produced in the Big Bang as well as small amounts of heavier elements. Around 4.57 billion years ago, the cloud began to contract, perhaps as a result of a shock wave from a nearby supernova. Inertia caused the rotating cloud to flatten into a disk. Most of the mass concentrated in the middle, and began to heat up. Eventually, the kinetic energy of the hydrogen was sufficient to overcome the electromagnetic repulsion between the protons, and fusion began. The resulting solar wind helped clear away much of the material which had not coalesced into planets or other orbiting bodies. <ref>[http://www.tufts.edu/as/wright_center/cosmic_evolution/docs/text/text_plan_1.html]</ref>. The sun is most likely a third-generation star.

The sun has a diameter of about 870,000 miles (1.4 million kilometers); some 1.3 million Earths could fit inside its volume. It is an average-sized, middle-aged star. Its surface temperature is 6000 [[Kelvin|K]], while the temperature of its core is around 13.6 million K. The inner layer of the sun, called the core, is where most fusion takes place. Beyond that is the radiation zone and then the convection zone. Outside that is the photosphere, the visible layer of the sun. It takes anywhere between 17,000 and 50 million years for photons produced in the core to be emitted at the surface, having been absorbed and re-emitted countless times. The atmosphere, including the corona, surrounds the photosphere. The sun is located about halfway between the center of the galaxy and its edge; it takes around 230-250 million years to orbit the galactic center. It is estimated to have made almost twenty of these trips.

The sun has a diameter of about 870,000 miles (1.4 million kilometers); some 1.3 million Earths could fit inside its volume. It is an average-sized, middle-aged star. Its surface temperature is 6000 [[Kelvin|K]], while the temperature of its core is around 13.6 million K. The inner layer of the sun, called the core, is where most fusion takes place. Beyond that is the radiation zone and then the convection zone. Outside that is the photosphere, the visible layer of the sun. It takes anywhere between 17,000 and 50 million years for photons produced in the core to be emitted at the surface, having been absorbed and re-emitted countless times. The atmosphere, including the corona, surrounds the photosphere. The sun is located about halfway between the center of the galaxy and its edge; it takes around 230-250 million years to orbit the galactic center. It is estimated to have made almost twenty of these trips.