Sun

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The Sun is a G2 class star. Our sun is a average size star and is has completed approximately slightly more than half of its life cycle at about 6 billion years. There are several separate layers of the sun. These layers include the core, layers of hydrogen, photosphere, chromosphere and the corona. These layers perform different functions within the sun and effect the entire solar region.

The Core of the sun is where nuclear fusion takes place. Nuclear fusion is the process where two hydrogen atoms are fused together to create helium and releases energy during the process. This energy radiates throughout the sun.

The layers above the core are wrapped in hydrogen which help supply the fusion process of the sun. The layer above this area is called the photosphere.

The Photosphere layer of the sun is were the sun emits light. The main feature that exist in this layer are called sunspots. Sunspots appear dark, when actually they are quite bright. They are cooler than the surrounding areas by at 2,000 F. This cooler surface produces less light than the hotter regions around it and this makes them appear dark against the hotter, brighter surrounding areas. Sunspots are magnetic storms/disruptions which are created in the northern and southern regions of the sun and make their way to the equator and disappear. The maximum to minimum cycle last 11 years. Sunspots affect life on Earth. Period of maximum sunspots cool the over all surface of the sun which lowers temperatures on Earth. Periods of low sunspot activity raise the sun's surface temperature, which raises the Earth's temperature. This in turn can affect climate and food production on Earth.

 The Chromosphere lies just above the photosphere and is an area of great disruptions on the sun. These disruptions include solar flares and prominences. Solar Flares and Prominences can affect communications and life on Earth. Solar Flares are small loop like structures  and prominences are large structures which can extend millions of miles from the surface of the sun. These structures send massive amounts of solar radiation towards the Earth. This radiation at times can affect communications on Earth and cause and increase in the Aurora's "Northern Lights/Southern Lights."

The Corona is last layer of the sun atmosphere. The Corona stretches past the orbit of the Earth. The Corona can reach temperatures up to 2 million degrees F. Solar Wind flows from the corona and reach the edge of the solar system called the heliopause. The Heliopause marks the edge of the sun's influence and the beginning of interstellar space.

Photos Courtesy of NASA/JPL