Nuclear Fusion. The Sun is considered an average and very stable star and should have enough fuel to last another 4-5 billion years.

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1 Our Solar System

2 Specific Outcomes Recognize that the Sun and the stars emit light by which they are seen and that most other bodies in space, including Earth's Moon, planets and their moons, comets, and asteroids, are seen by reflected light Describe the locationh and movement of individual stars and groups of stars (constellations) as they move through the night sky Recognize that the apparent movement of objects in the night sky is regular and predictable, and explain how this apparant movement is related to Earth's rotation Understand that the Sun should never be viewed directly, nor by use of simple telescopes or filters, and that safe viewing requires appropriate methods and safety precautions Cosntruct and use a device for plotting the apparent movement of the Sun over the course of a day; e.g., construct and use a sundial or shadow stick Describe seasonal changes in the lenght of the day and night an din the angle of the Sun above the horizon Recognize that the Moon's phases are regular and predictable, and describe the cycle of its phases Illustrate the phases of the Moon in drawings and by using improvised models. An improvised model mght involve such things as a table lamp and a sponge ball. Recognize that the other eight known planets, which revolve aroudn the Sun, have characteristics and surface conditions that are different from Earth; and identify example of those differences Recognize that not only Earth, but other planets, have moons; and identify examples of similarites and differences in the characteristics of those moons Identify technologies and procedures by which knowledge, about planets and other objects in the night sky, has been gathered. Understand that Earth, the Sun and the Moon are part of the solar system that occupies only a tiny part of the known universe.

3 The Sun

4 Important Facts The Romans called the sun Sol, which in English means sun. In ancient Greece, the sun was called Helios This is why our system of planets is called the Solar System. The Sun was born in a vast cloud of gas and dust around 5 billion years ago. At the center, an ever growing body of mass was forming. As the matter fell inward, it generated a tremendous amount of heat and pressure. As it grew, the baby Sun became hotter and hotter. Eventually, when it reached a temperature of around 1 million degrees, its core ignited, causing it to begin nuclear fusion.when this happened, the Sun began producing its own light, heat, and energy.

5 Nuclear Fusion Thermonuclear fusion is the process in which a star produce its light, heat, and energy. This happens at the core of the star. The core is superheated to millions of degrees. This heat travels towards the surface and radiates out into the universe. Through this thermonuclear process, stars "burn" a fuel known as hydrogen. The result is that they create another type of fuel known as helium. However, stars do not burn in the same way that a fire does, because stars are not on fire The Sun is the star that is at the center of our solar system. Starts are the heat source of the universe and come in all sizes, colors, compositions and temperatures. Starts emit light through nuclear fusion which happens deep inside the star. Our Sun is burning hydrogen at a rate of more then 1 million tonnes per second and turning that hydrogen into helium. By fusing the atoms together, the Sun produces heat and light which radiate outward. The Sun is considered an average and very stable star and should have enough fuel to last another 4-5 billion years.

6 The sun is the nearest star to Earth. It is at the center of the solar system. Like all stars, it is a blazing ball of fire. The Sun gives us light and keeps us warm.without it, Earth would be dark and freezing cold. No life would exist on earth if it weren't for the Sun. Light from the Sun can reach the Earth in only 8 minutes! This is called the speed of light. The Sun is nearly 93 million miles (approx 145 million km) from Earth Most objects we see in the night sky are stars which are light emitting objects and therefore are sources of energy. There are relatively small number of objects in the night sky that are seen by reflected light the most visible of which is the Moon. The planets and their satellites are seen because they reflect light from our Sun. The Sun is by far the largest object in the Solar System. 98% of all matter within the Solar System is found within the Sun. This means that all the planets, moons, asteroids, minor planets, comets, gas, and dust would all combine to make up only 2% of all the matter in the Solar System. The Sun is so large that the Earth could easily fit inside the Sun a million times. Because the Sun is so large compared to everything else, it is easily able to hold on to the rest of the matter, causing everything else to orbit around it.

7 Solar Flares During periods of high solar activity, the Sun commonly releases massive amounts of gas and plasma into its atmosphere. These ejections are known as solar flares. Some solar flares can be truly massive, and contain impressive power. On occasion, these more powerful flares can even cause satellites orbiting the Earth to malfunction. They can also interact with Earth's magnetic field to create impressive and beautiful light shows known as the Northern and Southern lights. In the northern hemisphere, these lights are commonly known as the Aurora Borealis

8 Can I look at the Sun? The Sun should never be viewed directly, nor by use of simple telescopes or filters. Safe viewing requires appropriate methods and safety precautions. The moment you begin looking at the sun, you start to develop a sunburn on your eyeball. Of the three types of light that the sun produces visible, infrared, and ultraviolet (UV). UV is the most damaging to structures within the eye, even when reflected off sand, snow or water. The cells of the cornea, the transparent outer layer of the eye, will blister and crack when overexposed to UV light. It's a lot like a normal sunburn. Symptoms of this condition, usually appear a few hours after the damage has occurred. They're identified by excessive tearing, tissue inflammation, and the feeling that you've rubbed your eyes with fine grit sandpaper. Luckily, the effect is almost always temporary, dissipating within 36 hours, and can be prevented by wearing UV-rated eye wear Permanent, complete blindness can also occur from staring at the sun over the long term. The eye's lens can be damaged from too much UV light, typically resulting in cataracts and invasive tissue growth. As UV-induced cataracts advance, they can obscure a patient's vision. If left untreated, they can eventually cause blindness. The only safe way to look at the sun through binoculars or a telescope is to install a solar filter which are very expensive If you can't afford a solar filter, you can always build a small pinhole projector or other indirect viewing method..

9 Activity 1: Pinhole Camera

10 Materials Shoebox Pin Sheet of white paper Tin foil Tape Procedure Cut a 5 cm squre out of one end of a shoebox Cover with a piece of tin foil. Tape into place making sure the tin foil is flat. Poke a small hole in the center of the tin foil with a pin. Place a sheet of white paper on the inside of the box at the opposite end. To view, hold the box above your head with the pinhole facing toward the eclipse. You will face the screen with your back to the eclipse. An upside down image will form on the screen. 4

11 Quiz 1: Our Sun