1. The sphere of life unfolds… Research done by: Sharlotte Mkansi Source: Internet http://www.dailygalaxy.com/photos/uncategorized/2008/09/02/atmosphere.jpg http://www.visionlearning.com/library/module_viewer.php?mid=107 http://www.rcn27.dial.pipex.com/cloudsrus/atmosphere.html

2. The importance of the atmosphere This is where the weather processes take place and our world climate is controlled by the atmosphere. – Water vapour can only rise up to the end of the troposphere(layer in the atmosphere), clouds can form and most likely we can have rain. The atmosphere contains the ozone layer in the stratosphere(layer of the atmosphere), which protects us from the dangerous Ultraviolet rays. The atmosphere contains the mesosphere(layer in the atmosphere),which burns meteors as they enter the earth and scatters them around. Meteors can be threatening to life on earth because they are very hot. Most importantly, the atmosphere contains the air we breathe. This “air” is all the gases that allow life to take place.

3. The thickness of the atmosphere The atmosphere in general is thick. It extends from the earth and up to the vacuum of the universe. – Troposphere: ± 17 Km – Stratosphere: ± 50 Km – Mesosphere : ± 80 Km – Thermosphere : ± 1280 Km – Ionosphere and Exosphere extend to the vacuum of the universe. Every layer of the atmosphere has its own important purpose to serve. They protect life on earth in many ways unimaginable.

4. Layers of the atmosphere Vacuum of the universe Beginning of the Exosphere and Ionosphere Thermosphere Mesosphere Stratosphere Troposphere

5. Breathtaking views of the atmosphere Aurora is the beautiful natural phenomenon that has enchanted mankind with mysterious movements, surreal shapes, and vivid colors dancing across the night sky. People travel for thousands of kilometers to see the spectacular aurora light shows in the Earth’s atmosphere. The breathtaking color displays of the Aurora Borealis, also called the Northern Lights, as well as Aurora Australis, also known as the Southern Lights, appear on clear, cold nights in the arctic sky during periods of solar activity. The shooting stars that we see at night occur in the mesosphere, which is 75 km to 100 km thick. They are called meteors in science and they enter the mesosphere while their high speed plunge towards the bottom of the atmosphere then they ignite. In most cases, they disintegrate and never reach altitudes(heights) lower than 30 km above sea level.

6. Composition of the atmosphere All of these gases are found within the troposphere of the atmosphere because all the other layers,except the stratosphere, do not contain any gases. Many people may think that oxygen is the most dominant gas in the atmosphere but it is not. The most dominant gas is Nitrogen and it is found in a large of about 78.08%.All the other gases constant in the atmosphere are: – Oxygen (O):20.95% – Argon (Ar ):0.93%