Heat And Light Of The Sun example essay topic

1,732 words
The Sun The sun is the largest object in the solar system. It is a middle-sized star and there are many other stars out in the universe just like it. Even though it is only a middle-sized star it is large enough to hold over 1 million Earth's inside if it were hollow. The temperature on the sun is far too much for any living thing to bear. On the surface it is 10,000 degrees Fahrenheit and the core is a stunning 27,000,000 degrees Fahrenheit. But don't worry we are over 90,000 million miles away, the sun could never reach us, at least not yet.

The sun is a still a middle aged star and later in its life it will become a Red Giant. In this stage it will get bigger, and closer to us causing a temperature increase and most likely the end of the world as we know it, but this will not take place for quite some time. But the sun is not our enemy, if it weren't for that big ball of burning gas there would be no life on this planet at all. We need its heat, its light, and its energy. Without these our planet would be frozen over like a big ice cube and there would be no signs or traces of life ever.

In total amount the sun provides about 2 pounds of energy to us every day. Yes, that's right only 2 pounds. The sun evaporates water from the earth's lakes, streams, and rivers. It also heats the earth and cools the earth at the same time. Without the Earth's atmosphere to protect us from the sun's ultraviolet rays we would be toast. This is kind of how the greenhouse effect takes place.

The greenhouse effect is when the atmosphere of the earth traps heat from the sun and lets sunlight heat plants, yet prevents much of the heat from getting out. In a similar way, the atmosphere lets sunlight through to the surface of the earth. The sunlight warms the earth, but the heat that created cannot easily pass back through the atmosphere into space. Now what is going on in the sun? When we look up we just see a bright object that makes us warm, sometimes gives us sunburn and gives us light, on the contrary. The sun is a mass of incandescent gas, a gigantic nuclear furnace where hydrogen is built into helium at a temperature of millions of degrees.

The sun is so hot that everything on it is a gas. About 75% of the sun is made up of hydrogen, about 23% is helium and the remaining percent consist of iron, copper, aluminum, and about 70 more elements that are commonly found on earth. Does this mean anything to you? Sunlight comes from the sun's atomic energy.

Scientists have found that the sun is a huge atom-smashing machine. The heat and light of the sun come from the nuclear reactions of hydrogen, carbon, nitrogen, and helium. So the sun is just one great big atom smashing, gas creating, nuclear furnace that gives off much appreciated energy. But this is not all that happens on the sun's surface, some exciting stuff does happen up there every once in a while.

Have you ever heard of a solar flare? A solar flare exists after a sunspot has existed for a long time and the magnetic lines of force usually become jumbled. As a result of this jumbling, magnetic energy is stored in the Corona (region of atmosphere above the chromosphere). The energy may be released in a spectacular discharge, which is a solar flare. A solar flare can be as wide as 367,000 miles and as high 500,000 miles out into space. A solar flare is nothing more than helium erupting from the sun like a volcano.

Sunspots, where most solar flares occur, are dark patches on the surface of the sun. This is where the gas of the sun is not so hot and causes it to take on a different color. A typical sunspot is about 22,000 miles in diameter and the number visible sunspots from satellites are about 5 to 100, it varies. How does the sun move?

It moves just like earth does, it spins on axis like a top. As earth moves around the Milky Way galaxy, the sun revolves around the center of it. It takes one day for the Earth to spin all the way around on the imaginary poles, and it takes a month for the sun to do the same thing. The sun's center rotates differently than its poles.

The region near the sun's equator takes a little less than a month to spin all the way around, but at its poles it takes just a little over a month. The reason why it does this is because it is a giant ball of gas, if it were solid like the earth, its different parts could not rotate at different rates. The earth takes a year to revolve around the sun, but the sun takes about 225 million years to make one revolution around the center of the Milky Way. During this period, the sun travels about 10 billion times as far as the distance between it and the earth.

The sun makes up 99.8% of the mass of the solar system. It is the biggest mass in the solar system. It is the closest star to earth and it is probably the oldest object in the Milky Way. It is 10 times older than the earth, it is 4,600,000,000 years old. Now that's a lot of years to be burning like it has.

How was the sun formed? Since it is impossible for us to know how the universe was created exactly, scientists have theorized that the sun was formed from a rotating mass of gases and dust. When the dust and gas combined they contracted and became so hot that nuclear reactions began, producing the sun's energy. They believe the planets were formed this way as well. Today the sun still contracts but from both inside and outside make it a stable yellow dwarf star. Scientists believe that the sun's life is halfway over and that it will continue to shine for another 5,000,000,000 years.

They believe that the center of the sun will shrink and become hotter. The outer regions of the sun will expand about 40 million miles swallowing up Mercury, the closet planet to the sun. Afterwards it will become so hot that life on earth could not exist. As it uses up its energy in the red dwarf stage it will become smaller, about the size of the earth.

In this stage it will be a white dwarf. It will throw off violent eruptions called nova explosions, as it becomes a white dwarf. It will stay a white dwarf for billions of years, and use up the last of its heat and energy. When the sun becomes a black dwarf the planets will be cold and dark. If by any chance the Earth still had an atmosphere at this point, which is highly unlikely, the gases of the atmosphere would have frozen onto the Earth's surface. Pretty scary, huh?

Well we won't have to worry about this because this won't happen for 5,000,000,000 years anyway. We won't survive the red dwarf stage anyway so it doesn't matter. In fact we will have probably used up all of earth's resources or have gone extinct by this time anyway so try not to lose any sleep over it. During an eclipse of the sun, scientists on earth can study the outer edge of the sun's atmosphere as the moon blocks off all of its light. Ancient worshipers of the sun believed that when there was an eclipse of the sun, god was punishing them.

When this happened they would most likely make sacrifices to try and make god happy. Well obviously we know it's not god doing it now but back then they didn't know what to believe. Many cultures worshiped the sun as if it was their God. The Greeks, the Egyptians, The Maya's, The Incas, they all believed that the sun was their god. The Greeks believed that a man drove a chariot through the sky carrying the sun as it moved from east to west throughout the day. Now, people today don't see the sun as a God but more of an important heat and energy source.

In ancient time people based the first clocks and calendars on the movement of the sun. Sundials were created, such as Stonehenge, to see the suns shadow and tell the time of day. Ancient people also used the sun to tell directions, they knew that it rose in the east and set in the west everyday, and that one whole day was the time it took the sun to get from one edge of the horizon to the other. Ancient calendars were based on the phases of the moon. The phases occur because sunlight reflected by the moon is seen from different angles as the moon circles the earth. Even today the sun has an important role in surveying and navigating people.

Surveyors can use the sun to calculate their own position and other positions on the earth. Well, that about does it as a summary for the sun. Even though this essay may have brought out some true facts about the sun there is still much more to know about the sun. Some stuff we don't even know about the sun and may never know, but what we do know is good. We know that it is the largest object in the solar system, it is the size of 1 million earth's and it hotter than 27,000,000 in the core, now that's cooking.

Bibliography

1. The World Book Encyclopedia, "sun" Robert W. Noyes 2. Why the sun shines 3. Science Book.