Earth and Space Review Notes

Natural Resources RenewableNonrenewable Can be remade/replaced within our lifetime or never run out ▫Trees ▫Plants ▫Animals ▫Oxygen/Carbon Dioxide ▫Fresh Water ▫Sunlight ▫Wind Energy ▫Ocean Tides Cannot be remade within our lifetime (takes millions of years) ▫Fossil Fuels (coal, oil, natural gas) ▫Minerals ▫Metal Fossil fuels are formed over millions of years from the remains of dead plants and animals under extreme heat and pressure!!

Alternative Energy Sources Solar energy –energy from the sun (solar panels are used to capture this energy) Geothermal energy –heat energy that comes from heat within the Earth Hydroelectric energy-energy that comes from moving water (dams with turbines are usually used to help generate electricity) Wind energy –energy that comes from moving air (the windmills are turbines) Biomass –energy from plants and animals that just died (can be burned for fuel) Ethanol and vegetable oil can both run cars

Water Cycle Very important because it keeps us supplied with fresh water. Powered by the Sun’s energy. Evaporation –Sun’s energy turns water into water vapor (gas) which rises into air Condensation –water vapor cools and turns into liquid water drops, forming clouds Precipitation –drops get heavy and fall back to Earth Run-off –water flows across land

Weathering Weathering is when rock is broken down Water, wind, ice, plant roots, can all cause weathering Weathering turns big rocks into smaller rocks and those smaller rocks into sand

Erosion Erosion is when rock or sediment is carried away Water, wind, ice (glaciers), and gravity can all cause erosion

Deposition Deposition is when sediment is dropped in a new place When wind, water or ice slows down or stops it drops the sediment (deposition)

Landforms - Canyons and valleys are mainly formed by erosion Canyon

Landforms Sand dunes are formed by deposition Deltas are formed by deposition at the mouth (end) of a river. Example: Mississippi River Delta

Landforms Caves form mainly by chemical weathering ▫They have stalactites that hang from the ceiling ▫They have stalagmites that grow on the ground

Rocks, Rock Layers, and Fossils Sedimentary Rocks –form when small bits of rock (called sediment) squeeze together to form layers Fossils form in sedimentary rock Fossils can tell you what the area was like millions of years ago; Example: a fossil of a fish may indicate the area was once covered by water Youngest/newer layers are towards the top Older layers are further down

SUN Largest object in our solar system –HUGE! ▫But… it is on a medium size star when compared to other stars in the universe ▫Our Sun looks big because it is much closer A star Made of gas (hydrogen and helium) All planets in our solar system orbit the Sun (due to it’s gravity) Provides light and heat to Earth Sunspots (darker spots) –cooler areas

Planets Planets orbit the Sun Order of the Planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune Remember: My Very Excellent Mother Just Served Us Nachos First four planets –inner planets- smaller, made of rock Last four planets –outer planets- larger, made of gas Jupiter –largest planet, Mercury –smallest planet

Earth vs. Moon EARTHMOON Sphere made of rock Larger –more gravity Has water Has air and atmosphere Few craters (meteors burned up by atmosphere) Life Orbits the Sun (1 year) Rotates in 1 day Erosion Sphere made of rock Smaller less gravity No liquid water No air or atmosphere Many craters (no atmosphere to burn meteors) No life Orbits the Earth (1 month) Rotates in 1 month No erosion

Moon Has no light. The light we see is really the Sun’s light reflecting off the moon. Tides- the moon’s gravity pulls on the Earth’s oceans, causing high tides two times a day Phases- the Moon appears to change shape, because we see light reflecting off it from different positions as it orbits the Earth ▫New ▫Crescent ▫Quarter ▫Gibbous ▫Full Lunar Cycle –takes one month (moonth) for it to orbit the Earth

Rotation vs. Revolution/Orbit RotationRevolution/Orbit The Earth takes one DAY, or 24 hours, to rotate (spin on it’s axis) This causes day and night. (Think rotation roDAYtion) The Earth takes one YEAR, or 365 days, to revolve (or orbit) around the Sun.

Seasons The tilt of the Earth causes the 4 seasons. When we are tilted towards the Sun it is summer. When we are tilted away from the Sun it is winter. The northern and southern hemispheres have opposite seasons. (Example: When it is summer in the northern hemisphere, it is winter in the southern hemisphere).