1) Astron
omy- I particularly enjoyed the unit on astronomy. We studied The sun,the phases or the moon and space exploration, yet my favorite lesson was that on the heliocentric and geocentric theories. I found the history of these theories to be particularly fascinating. Geocentricity is the theory that the Earth is the center of the universe and everything revolves around it. This theory was widely believed in the middle ages, yet now almost everyone believes the theory of geocentricity, the theory that the sun is the center of our solar system.2) Atmosphere-T
his year, we also studied Earths atmosphere, a topic from which I learned a lot. I particularly enjoyed learning about the different layers of the atmosphere. The first layer is the Troposphere inside of which weather occurs. The second layer is the Stratosphere, the layer that jets fly through. This layer absorbs harmful rays from the sun because the ozone layer is located at the bottom. Next is the Mesosphere, the layer that burns any meteor or rock fragments coming to Earth. The fourth layer is the Thermosphere, the layer that space shuttles orbit in and auroras occur. Last is the Exosphere, the layer where the atmoshere merges into space.3) We
also studied geology, learning of plate tectonics, earthquakes and different types of rocks and minerals, yet my favorite subject was the types of volcanoes. We learned that there are three types of volcanoes- shield volcanoes, cindercone volcanoes and composite volcanoes. Shield volcanoes are gently sloping hills from which lava may flow. cindercone volcanoes are volcanoes that erupt once, yet usually are very explosive. They may erupt lava, ash and bombs (very large rocks). Composite volcanoes are tall, cone shaped volcanoes that may be calm or explosive.
4) Another topic that we looked at was weathering and erosion- two processes that work together to break down and carry away the rocks and sediment at Earths surface. I particularly enjoyed learning of the different types of mass movement( processes that move sediment downhill). These include landslides-the quick movement of rocks and soil downhill, mudflows- the downhill movement of water, rock and soil, slump- a large mass of moving material and creep- the very slow movement of rocks and soil.
5) The last and most recent topic we studied was Earth's waters. I enjoyed learning of the unique properties of water. Water is "the universal solvent meaning it can dissolve many different substances. Water has specific heat meaning it is the only substance found in both solid, liquid and gas in normal temperatures on Earth. Water also has high surface tension, meaning it sticks to both other water molecules and other substances.
