I appear bigger and brighter to you because I am closer to you than other stars.  Astronauts find that I am shrinking or contracting.  Astronauts believe that we stars are great nuclear furnaces.  Every second, 600,000,000,000 kilograms of hydrogen are changed to helium, this is a source of my heat.  In some parts, I am rising or sinking.  I am a medium sized star and about 600 times larger than the other planets.  If the earth was the size of a golfball, than I would be a globe fifteen feet across.  I am about 93,000,000 miles away from the earth.  My diameter is about 865,400 miles - 100 times more than the earth.

Surrounding my chromosphere is an outer atmosphere called the corona.  The corona is made up of thin gases that are very, very hot, almost 3 million degrees (F.)  My corona stretches outward for millions of miles into space.
 

Always remember that I am too bright for your eyes, never look directly at me, even when you are wearing sunglasses.  My rays are strong enough to damage your eyes or even to make you go blind.

I was formed about 4.6 billion years ago.  I spin around once every 27.4 days.

My core or center is made of a gas called helium.  This is the sun's hottest part.  It is where the sun's heat and light energy are made.  Sunspots are cooler areas which look like dark blotches on my surface.  They are most common about every 11 years.  A lot of me is made of a gas called hydrogen.  This is my fuel supply.  Slowly, over billions of years, the hydrogen is being used up.  However, scientists have calculated that I've only used up about half of my supply of hydrogen fuel.

Bibliography

Asimov,Isaac. Reedy, Francis. The Sun and Its Secrets. Milwaukee: Gareth Stevens, 1990.

Stacy, Tom  Bull,Peter Quigly,Sebastian. Sun, Stars and Planets. New York: Random House, 1991.