6th Grade Rockin Review
The Moon and It's Phases
lunar Cycle- Refers to the moon's continuous orbit around the earth. The lunar cycle takes about 29 days to complete the process.
Waxing- When the moon's surface is becoming more visible. Look to the left side of the moon. The moon should look like a letter "C".
Waning- When the moon's surface is becoming less viable. Look to the right side of the moon. The moon should look like the curvy part of the letter "D".
Gibbous moon- It’s when the Moon is more than half full when you look at it from the perspective of Earth. The reason the light changes has to do with how the Moon orbits the Earth.
Crescent- The figure of the moon as it appears before its first quarter phase or after its third quarter phase
Moon Eclipses and seasons
Who was Copernicus? Copernicus was a man who proposed that the earth was revolving around the sun and not viscera. This discovery helped astronomers understand more about our solar system.
Since the earth revolves around the sun and spins on a tilted axis the hemisphere are exposed to the sun at different times and at different amounts. These variations of sun exposure are tracked by seasons.
In winter the earth is closer to the sun, and you'd think the closer we are the warmer, yet we get colder weather. During the winter, the sun's rays hit the Earth at a shallow angle. These rays are more spread out and minimizes the amount of energy that hits any given spot. Also, the long nights and short days prevent the Earth from warming up.
How come there aren't lunar eclipses every month? Well, the moon takes about a month to orbit around the Earth. If the moon orbited in the same plane as Earth’s orbit, we would have two eclipses every month.The moon’s orbit is inclined to Earth’s orbit by about 5 degrees, so it takes months and months until the moon is realigned with the earth. That’s why there’s not an eclipse every month.
When the earth spins it takes 24 hour more or less. At any time half of the Earth faces the sun this part has day. The other half of the Earth faces away from the Sun reviving no light making it night.
Equinox- the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length (about September 22 and March 20).
Solstice- either of the two times in the year, the summer solstice and the winter solstice, when the sun reaches its highest or lowest point in the sky at noon, marked by the longest and shortest days.
Alfred Wegener was the scientist who proposed the Continental Drift Theory in the early twentieth century. Simply put, his hypothesis proposed that the continents had once been joined, and over time had drifted apart.
Convergent boundaries- where two (or more) tectonic plates or fragments of the lithosphere move toward one another and collide.
Divergent boundaries- a linear feature that exists between two tectonic plates that are moving away from each other.
Transform boundaries- Is where two of the floats - two tectonic plates - side alongside each other. When this happens, the scraping of the two plates causes earthquakes
Juan de Fuca Plate is just off the coast of Washington. The Juan De Fuca plate subducted under the North American plate. As the oceanic crust goes under the continental crust it goes deeper into the earth where it eventually melts and sends magma upward that forms the Cascade Volcanoes.
Convection in the Earth is what causes flows in the plastic layer of Earth. This creates forces on the plates in the lithosphere to move because of convection.
Rift Zone- A feature of some volcanoes, especially shield volcanoes, in which a linear series of fissures in the volcanic edifice allows lava to be erupted from the volcano's flank instead of from its summit.
Subduction Zone- when pieces of crust that slowly move across the surface over millions of years. When two tectonic plates meet, one may slide underneath the other, curving down into the mantle.
The Channeled Scablands were created by the cataclysmic Missoula Floods that swept periodically across eastern Washington and down the Columbia River Plateau during the Pleistocene epoch.
Sedimentary- Sedimentary rocks are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Example: Sandstone is sand grains cemented together into solid stone.
Metamorphic- Metamorphic rocks are fromed the transformation of existing rock types, in a process called metamorphism, which means "change in form". The original rock is heated and pressurized, causing profound physical and/or chemical change. Example: Marble is a metamorphic rock that comes from metamorphosed limestone or dolomite.
Igneous- Igneous rock is formed through the cooling and solidification of magma or lava. Example: Basalt Lava is a hard, black volcanic rock.
Stratification- A formation of layers in rocks.
By fining the age of one section of rock could help you find out how old the whole rock is. the climate and condition directly effects rock formations.
Floods could lead to the tipping or placement of younger layers under older layers. As their eroded or moved out of place they shift and either tilt or younger rocks move underneath.
living organisms sometimes form land features. Coral islands are formed by coral polyps that build over a long period of time and then reaches the surface of a body of water. Oil is made by organic materials going under intense amounts of pressure.
A video on the rock cycle^