Layers of the Sun - Eye on the Sky

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Layers of the Sun Let’s see how the energy of the Sun moves from its inner core to the outer regions of its atmosphere. The CORE of the Sun is where energy is first formed. Its temperature is 27 million degrees Fahrenheit. From the core, energy moves outward toward the Sun’s surface and surrounding atmosphere. The energy moves through several layers or zones. Remember the Sun’s layers are made of hot gases and they not solid like the Earth’s layers. The energy moves out from the core through the RADIATIVE ZONE. Scientists calculate the temperature to be cooler than the core—it is only a 4.5 million degrees Fahrenheit. That’s HOT! The Sun’s next layer is the CONVECTION ZONE. Convection is how energy moves from the inner parts of the Sun to the outer part of the Sun that we see. We can see convection when we look at a pot of boiling water. Convection is what makes large, slow moving bubbles form in a bowl of hot miso soup. Through convection the heat moves from the bottom of the hot soup to the

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soup’s surface where it is cooler. The Sun’s convection zone is a bubbling 2 millions degrees Fahrenheit. The PHOTOSPHERE, the Sun’s visible surface, is the next layer of the Sun. The bubbling motion of the convection layer makes the granular patterns we see on the photosphere. The granules may look small in pictures, but scientists estimate they are really about the size of the Moon. Sunspots—indicating giant magnetic storms—are also visible on the photosphere. Most of the time sunspots come in pairs—like the poles of a magnet. Even though sunspots are very, very hot they look darker than the rest of the Sun because they’re cooler. This layer of the Sun has cooled off to 10,000 degrees Fahrenheit and the Sunspots are even cooler—about 7,800 degrees F. Just above the photosphere is the CHROMOSPHERE with huge solar flares and loops of hot gases shooting up thousands of miles. Things begin to heat up again here—the temperature is estimated to be 50,000 degrees F. And above the chromosphere is the CORONA—we can only see it during a total solar eclipse. The corona is very, very hot—4 million degrees F. It is also very thin. Scientists are still trying to figure out why it is hotter than other parts of the Sun. This is a big mystery… Sometimes when the Sun is very active, the hot gases shooting out of the Sun are so powerful that they blow away from the Sun into the solar system. They stream away in all direction from the Sun and can move up to 1 million miles per hour. These streaming, hot gases are called the SOLAR WIND. SOLAR FLARES are sudden, bright outbursts of energy that happen as the Sun’s magnetic fields twist, tear and reconnect. CORONAL LOOPS are magnetic loops with strong magnetic fields. Giant arches of gas that erupt on the Sun are called PROMINENCES. They can last several days. CORONAL MASS EJECTIONS coming from the Sun have the most energy of all these solar events. Sometimes they head toward the Earth where they can cause communications disruptions and damage satellites. We are very lucky here on Earth because we have a powerful magnetic shield around us which protects us from getting too much energy. Earth is the perfect home planet for us!

The Sun is a very dynamic and active star!