The Solar System > 1 Star > 8 Planets > 63 (Major Moons) > Asteroids, Comets, Meteoroids Terrestrial Planets (Mercury, Venus, Earth, Mars) >Closest To The Sun > Small Masses >Rocky and Solid Surfaces >No Rings >High Densities >Slow Rotation >Weak Magnetic Field >Few Moons Jovian Planets (Jupiter, Saturn, Uranus, Neptune) >Far from Sun >Fast Rotations >Large Masses >Gaseous Surface >Strong Magnetic Field >Many Rings >Low Densities >Many Moons Meteoroids- interplanetary rocky material smaller than 100m (down to grain size). > called a meteor as it burns in the Earth’s atmosphere >if it makes it to the ground, it is a meteorite Comets- Dirty snowballs – dusts and rock in methane, ammonia and ice. Nebular Theory for Solar System formation- Our Sun and the planets began from a cloud of dust and gas (Nebula) >As the cloud contracts under it’s own gravity, the sun is formed at the center. >The cloud starts to spin and the smaller it contracts, the faster it spins. >Cloud forms a flattened, pancake shape. >A flattened solar nebula disks exists after cloud spins and contracts. >Condensation nuclei form clumps that grow into moon-size planetesimals >Solar wind from the star formation (Sun forming) blow out the rest of the gas >Planetesimals collide and grow >Planetesimals form the basic planets over hundred million years >Star- A ball of matter that is pulled together by gravity, and that gives off energy as a result of NUCLEAR FUSION. - Nuclear Fusion- when two atoms bond together to make one heavier atom. The process releases large amounts of energy. >Composition of Stars- The two most abundant elements in stars are HYDROGEN and HELIUM. -Scientist determine the composition by studying the LIGHT that comes from a star. >How light shows composition- when elements in a star burn, they give off certain colors of light. The color of light corresponds to a specific wavelength of the light. >Magnitude- The Brightness of a star depends on three things -Size -Temperature -Distance from us >Apparent Magnitude-How bright a star is when viewed from Earth. A very large, hot star could look dim just because it is so far away. (How bright we see it) Absolute Magnitude- The amount of light that is actually given off by a star. (How bright it actually is ) >Constellations- are patterns of stars in sky. Earth’s Systems- Planet Earth is made up of different spheres: >Lithosphere- Solid part of Earth (Includes the crust and mantle) >Atmosphere- Gaseous part of Earth. >Hydrosphere- Water part of Earth. >Biosphere- Living Things on Earth. Earth Spheres- (Hydrosphere, Lithosphere, Atmosphere and Biosphere) are interconnected. - Many substances ( e.g., Water, Carbon, Nitrogen) cycle through Earth’s spheres. These cycles are called biogeochemical cycles. >The Water Cycle- (moves through the Atmosphere, Biosphere, Hydrosphere & Lithosphere) - in Water Cycle, water passes from vapor in the atmosphere as rain onto the land or body of Water. - the Water then transfers from the lithosphere back into the atmosphere through evaporation (liquid water changes to water vapor) & transpiration (liquid water from plants changes to water vapor). - that water then condenses (water vapor changes to liquid water) in the colder atmosphere and its starts to rain, moving water from the atmosphere to the hydrosphere continuing the cycle again. > The Nitrogen Cycle (Moves through the atmosphere, biosphere, & lithosphere). - Nitrogen makes up 78% of Earth ‘s Atmosphere. - Most Nitrogen is in gaseous form, which makes it not usable by life on Earth. - Microbes (microscopic organisms) in the soil and in roots of some plants coverts or “fix” nitrogen into a form that plants can use (Nitrogen fixation). - Humans and Animals get the nitrogen compounds by eating plants or by eating other animals that have eaten the plants. - Microbes return the nitrogen from decaying matter and waste to the gaseous form and the cycle continues. >The Oxygen Cycle (moves through the atmosphere, biosphere, hydrosphere & lithosphere) - Oxygen can be dissolved in the air or in water. - Plants and animals breath oxygen and return it to the air and waste as carbon dioxide. - Through photosynthesis, plants converts carbon dioxide and water into carbohydrates, and release oxygen. - Algae in the oceans and other water bodies replace about 90% of all oxygen used on our planet. >The Carbon Cycle (moves through the atmosphere, biosphere, hydrosphere and lithosphere) - Large amounts of carbon are stored in the form of fossil fuel (oil, coal, natural gas). Burning fossil fuels releases carbon into the atmosphere in the form of carbon dioxide. (CO₂) - Large amounts of carbon are also stored in tissues of trees (such as woods). So carbon dioxide (CO₂) is also released when wood is burned or when it decays. Earth Systems Science is the study of how the four spheres of the Earth interact continually, each affecting the others. The Earth is made up of 3 main layers 1. Crust – Thinnest layer of the Earth that ranges from only 2 miles in some areas of the ocean floor to 75miles deep under mountains. - Made up of large amount of silicon and aluminium. - Two types of crust: Oceanic Crust and Continental Crust. - Composed of plates on which the continents and oceans rest. 2. Mantle- Solid but capable to flow (like asphalt or fudge) - Thickest layer of Earth (Making up 70% of the Earth’s mass) - The hot material (Magma) in the mantle rises to the top of the mantle, cools, then sinks, reheats, and rises again. These convection currents cause changes in the Earth Surface. 3. Core- 3.1- Outer Core- Molten (Liquid) metal that is about 4,700 ◦C (8,500 ◦F) - Located about 1,800 miles beneath the crust and is about 1,400 miles thick. - Composed of the melted metals nickel and iron. 3.2. Inner Core- Solid sphere composed mostly of iron. - It is believed to be as hot as 6,650 ◦C (12,000 ◦F) - Heat in the core is probably generated by the radioactive decay of uranium and other elements. - It is solid because of the pressure from the outer core, mantle, and the crust compressing it tremendously.
