Sun

Sun. Isn't it such a small word? Yea, it is. But, why does it mean so much to organisms? It does mean a lot to organisms, organisms from the beginning of time and organisms from our time! But why? Because it gives us energy, especially plants. It helps them survive with its light. Also, it helps them bring out the process of PHOTOSYNTHESIS. Photosynthesis is when plants make sugars and starches by using sunlight or solar energy. In addition, the sun is a FRAME OF REFERENCE. A frame of reference is a background or point that is assumed to be stationary and is used for comparison when motion is described. That and the moon are our main frames of references. When we see the sun in the EAST, we know that it is rising or has already risen. When we see the sun in the WEST, we know that the sun is setting or is getting ready to set. There are also many layers and parts of the sun. The interior of the sun consists of the CORE, the center of the sun, the RADIATION ZONE, the middle layer of the sun, and the CONVECTION ZONE, the outer layer. The core is where a big portion of the energy is produced. The radiation zone is an area of extremely tightly packed gas where energy is transferred, usually, in the form of electromagnetic radiation. The convection zone is where blazing gases at the lower area rise and slowly cool down when they near the top of the convection zone.

I believe learning about the sun is, well, interesting. I mean, what would we do without the sun? It has helped people from the earliest of times. In earlier times, organisms, mainly humans, used the sun to tell time. Seeing the position the sun was in gave them an idea about what time of day it was because they didn't have watches and clocks like we do. See how much the sun affects us? Think about it, how would you survive without the sun? You may be fatigued on a hot and humid summer day, but if there was no sun we would be freezing to death. And when I say freezing to death, I mean it literally.

These are some more interesting facts:
1.) The sun is 1,390,000 kilometers in diameter. It's mass is 1,989,000,000,000,000,000,000,000,000,000 kilograms. The temperature at the surface is 5800 Kelvins (absolute 5800), and the temperature at the core is 15,600,000 Kelvins (absolute 15,600,000).
source: The Nine Planets
hyperlink: http://www.nineplanets.org/sol.html
2.) This site is a virtual "field trip" and it is about 20 minutes long (it says so on the site). There are a couple of MPEG movies in this, too. To go on this "field trip", go to http://www.astro.uva.nl/demo/sun/.
source: Sterrenkundig Institute

PICTURE from: (click on picture to see a larger image)
http://fusedweb.pppl.gov/CPEP/Chart_Pages/5.Plasmas/Graphics/Sun/Layers.gif