|"Keep your eyes on the stars, and
your feet on the ground."
- Theodore Roosevelt
The Sun's Layers - The core is the center section of the Sun. Scientists calculate that the thermonuclear reactions inside the Sun make the core a searing 14 million degrees celsius (25 million F). This number is so high it is hard to imagine the intense heat it generates. If you could heat the head of a pin to this temperature it would be so hot that it would burn everything for miles around it.
Going outward from the core the next level is the radiative zone. The energy has left the core travelling in electromagnetic waves. It then reaches the convective zone. It is in this area that the energy heats the plasma which rises to the surface of the Sun and we can observe it as granules.
The photosphere is the next layer of the Sun and it is the layer that you see when you look at the Sun. It is the one that is most prominent. The chromosphere is an almost completely see-through layer of the Sun that sits right on top of the photosphere. The only way you can see the chromosphere is to look at the red glow surrounding the Sun. The temperature in the chromosphere rises slowly as you get toward the outer edges; it rises from approximately 4300 degrees to 8300 degrees at the edge. At that point the temperature rises sharply.
The atmosphere of the Sun extends from the photosphere and it is made up of two parts: the chromosphere, and the corona. We are unable to see the atmosphere but scientist have found a way to study it. They use an instrument called a coronagraph which produces an artificial eclipse. Scientists need either a total solar eclipse or an artificial one to study either part of the Sun's atmosphere. Since natural total solar eclipses do not occur often enough to keep Sun research ongoing using the coronagraph makes it possible for Sun research to continue.
The chromosphere is a layer of gases that forms the inner part of the Sun's atmosphere. It is a relatively narrow layer being only 10,000 km (6,200 mi.) high with temperature that range from 1,000,000 degrees C (1,800,000 F) near the upper limits and 6000 degrees C (10,800 F) at the lower areas.
The Corona is the outermost layer of the Sun's atmosphere. The corona is so thin that the only time you can physically see it is during a solar eclipse, when the glare of the Sun (its photosphere) is blocked by the moon. At one million degrees Celsius the temperature of the corona is very high. It is so hot that it emits light at X-ray wavelengths. Interestingly, the Sun actually gets hotter as you get further away from the center.
If you look closely at the picture on the right, you'll also see solar flares in the chromosphere. Solar flares are caused by the magnetic field of the Sun. The plasma of the Sun is carried along the magnetic field lines.
There is a mystery surrounding the Sun that scientists have not been able to work out. The commonly accepted theory as to how the Sun works is that it works much like a nuclear bomb works through fusion now they are not certain this is the case. When hydrogen melds to helium neutrinos are formed. With the amount of fusion occuring in the Sun the Earth should be bombarded by neutrinos yet that does not happen. In the 1970s American scientist Raymond Davis worked out for the first time a way to fuse hydrogen to helium. He was attempting to simulate the Sun's energy production. He didn't expect to get very many neutrinos; however, he unexpectedly got only one-third the amount that he expected. This shortage suggested that scientists may be wrong in how they think the Sun works. Today research continues trying to solve this mystery.
©Copyright 1998 Elizabeth
Beckett, Holly Bernitt, and Vishwa Chandra.