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Download The sun is a star. It is a huge, spinning, glowing sphere of hot gas
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It's hot enough to melt any metal. It's so far away that its light takes eight minutes to reach your eyes. If it were a hollow ball, more than one million Earths could fit inside it. The sun is a star. It is a huge, spinning, glowing sphere of hot gas. The sun is just like the stars that you see in the night sky. It appears so much larger and brighter than the other stars because we are so close to it. The sun is the center of our solar system. All of the planets in our solar system, including Earth, orbit around the sun. How far is the sun from earth? The sun is at an average distance of about 93,000,000 miles away from Earth. It is so far away that light from the sun, traveling at a speed of 186,000 miles (300,000 meters) per second, takes about 8 minutes to reach us. Like all of the other planets in our solar system, Earth does not travel around the sun in a perfect circle. Instead its orbit is elliptical, like a stretched circle. Does the Sun rotate? • Let’s check it out? • http://apod.nasa.gov/apod/ap140312.html Does the Sun revolve? • NO it does not! What is the sun made of? The sun is a huge, glowing sphere of hot gas. Most of this gas is hydrogen (about 70%) and helium (about 28%). Carbon, nitrogen and oxygen make up 1.5% and the other 0.5% is made up of small amounts of many other elements. The sun shines because it is burning hydrogen into helium in its extremely hot core. This means that as time goes on, the sun has less hydrogen and more helium. Why does the sun have spots? The sun has a magnetic field that is twisted around inside the sun as it spins. There are places on the sun where this magnetic field rises up from below the sun's surface and pokes through, creating sunspots. Sunspots are magnetic and often have a north and south pole like a magnet. They come and go over the surface of the sun and last from a few days to a few weeks. How big is a sunspot? The average sunspot is about the size of the entire planet Earth! However, sunspots come in a variety of sizes ranging from hundreds to tens of thousands of miles across (many times larger that Earth). Scientists measure the total size (area) of all of the sunspots seen on the sun every day to get a measure of how active the sun is. Sunspots are not permanent. They appear and disappear on the surface of the sun. They are cooler than the rest of the sun, but are still very hot! Click on the telescope see current images of the sun