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we often c sun in the sky but do u know how it works i tried here to present various facts ![[sun parts]](http://observe.arc.nasa.gov/nasa/exhibits/sun/graphics/sun8.jpg) InteriorThe solar furnace that converts hydrogen into helium is deep within the Sun in a region called the core. The difference in temperature between the core and the surface of the Sun forces the energy to travel outward. It travels as radiation (i.e., light and more energetic forms of radiation) through a region called the radiation zone. In the outer part of the Sun's interior, heated solar material circulates in large cells, carrying the energy with it. This process is called convection, and this part of the Sun is called the convection zone.PhotosphereAbove the convection zone is the photosphere. The photosphere is the part of the Sun that we see. It is the Sun's lower atmosphere. The photosphere is a few hundred miles thick. It gives off most of its energy as visible light and heat. ![[Photosphere of sun]](http://observe.arc.nasa.gov/nasa/exhibits/sun/graphics/sun_9and10.jpg) ChromosphereAbove the photosphere is the chromosphere. The chromosphere is several thousand miles thick, but because the gases in the chromosphere are so thin and emit very little light, the chromosphere is hard to see. It can be observed through special filters and during solar eclipses when the much brighter photosphere is blocked out by the Moon. The chromosphere's color is orange-red. CoronaThe outermost layer of the Sun is the corona. The corona extends millions of miles into space. The corona is the hottest part of the surface of the Sun. It has temperatures reaching millions of degrees. Because the corona is millions of times fainter than the photosphere, it can be seen only during solar eclipses or with specially designed scientific instruments called coronagraphs.
 How the Sun Works -- Its Violence ![[Corona image]](http://observe.arc.nasa.gov/nasa/exhibits/sun/graphics/sun_corona.jpg) The Sun we see from Earth is a benign, glowing, yellow ball. But on closer examination, we see that it is far from quiet. The surface exhibits much violence and is frequently marked with spots and eruptions. With the right scientific instruments, we can see flares, glowing prominences, and loops thousands of miles across.The photosphere, chromosphere, and corona all have different forms of activity. They bear such interesting names as spots, faculae, plages, spicules, flares, holes, and prominences. Occasionally, the Sun will blow off a chunk of the corona tens of thousands of miles across. These are called coronal mass ejections, and they travel at hundreds of miles per second away from the Sun. If one hits the Earth, it can cause a magnetic storm. Scientists who study the Sun generally agree that solar activity, as the violence we witness is called, is caused by magnetic fields in the Sun's surface layers. The Sun is not a solid body. It rotates faster at the equator than it does at the poles. Scientists believe that this difference in rotation leads to a twisting and bending of the Sun's magnetic fields. They don't agree on exactly what happens, but in general, some sort of magnetic short circuit occurs which releases energy from the magnetic fields into the solar gas. The released energy produces solar flares, prominences, and the other forms of solar activity. One of the reasons so little is known about the details of solar activity is that much of it can only be seen with X-ray telescopes. Since the Earth's atmosphere absorbs X-rays, solar X-rays can only be studied from spacecraft above our atmosphere. The Soft X-ray Telescope on the Japanese spacecraft Yohkoh was built specifically to study the Sun at these high energies. The telescope was sponsored by the Lockheed Martin Advanced Technology Center in California and by NASA. The high-resolution X-ray pictures shown in this exhibit come from Yohkoh. Yohkoh is the Japanese word for sunbeam. hope it is helpful for u all |
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abt our SUN!!!!!!!!!
