6th Science PowerTime Vocab

Term Definition
Composition the material that something is made up of
Asthenosphere a layer of hot soft rock in the upper mantle
Lithosphere the crust and the very top portion of the mantle together
Tectonic plate large and small rock slabs that make up the lithosphere
Plate boundaries a place where two or more plates meet
Crust a thin layer of rock that surrounds the Earth
Mantle Earth’s thickest layer, it has a more rigid upper portion and a softer, lower portion
Outer core a layer of hot liquid metals surrounding the inner core
Inner Core a ball of hot, solid metals at the center of Earth
Density the quantity of matter in a given amount of space
Convection The transfer of heat through a fluid, due to density changes
Convergent to come together
Divergent to move apart
Transform boundary a boundary where plates slide past one another
Hot Spot a thin spot in the crust that allows magma to rise to the surface; it is not located near a boundary Mineral
Cleavage the tendency of a mineral to break along smooth flat planes parallel to zones of weak bonding
Fracture the tendency of a mineral to crumble or break in no particular pattern
Luster The way in which a mineral reflects light.
Streak the color of a mineral’s powder
Igneous Rock Forms when molten rock cools and becomes solid.
Metamorphic Rock Forms when heat or pressure causes older rocks, to change into new types of rocks.
Sedimentary Rock Forms when pieces of older rocks, plants and other loose material get pressed or cemented together.
Weathering a process that breaks down rock and other substances at Earth’s surface
Erosion the movement of rock particles by water or wind
Deposition the process in which transported sediment is laid down
Delta a land form created by deposition of sediment from a river flowing into the ocean. It forms at the mouth of the river.
Nonrenewable resource a resource that exists in a fixed amount or is used up faster than it can be replaced.
Renewable resource A natural resource that can be replaced in nature at about the same rate that it is used up.
Conservation The process of protecting or saving a natural resource. Evaporation
Condensation the process in which water vapor becomes a liquid
Precipitation the process in which atmospheric water falls to the ground as rain, sleet, snow, or hail.
Convection the method of heat transfer by density differences in a fluid
Conduction the method of heat transfer by direct contact
Radiation the method of heat transfer over a distance
Weather atmospheric conditions at a particular time and place
Climate weather conditions in a particular place over a long period of time
Air pressure a force exerted by moving air molecules
Wind high pressure areas of air moving to low pressure areas caused by uneven heating of Earth’s surface
Low pressure area This is an area of warmer, rising, less dense air. This is associated with stormy weather or cloudy skies.
High pressure area This is an area of cooler, sinking, more dense air. This is associated with clear skies.
Land breeze This occurs when a breeze blows from the land to the sea at night when the land cools off. It is due to higher pressure moving to lower pressure.
Sea Breeze This occurs when a breeze blows from the ocean to the land during the day due to higher pressure moving to lower pressure.
Jet stream fast flowing, narrow air currents found in the atmosphere Geocentric model
Heliocentric model (helio means sun) Sun centered model of the known universe. The planets revolve around the sun. Copernicus was 1st accredited with this model. Galileo supported it, as did Kepler and Newton.
Gravity The force of attraction between all masses in the universe. It governs all motion in the solar system.
Comets small objects, that orbit the sun, made mostly of ice with bits of rock and metal. They have a glowing tail that of gas and dust. It has a predictable orbit.
Asteroids a small, rocky, irregularly shaped bodies that orbit fairly close to the sun.
Meteors A tiny rock in space, which becomes a meteorite when it enters a planet’s atmosphere
Rotate when an object spins around an axis (the Earth makes a complete rotation on its axis in 24 hours)
Revolve when an object makes a complete circle around another object (It takes the Earth 365 days to go around the sun)
Solstice When the Sun is farthest from the equator (2 times per year
Equinox When the Sun crosses the equator (2 times per year
Polaris the north star that appears to not move due to the northern point of Earth’s axis pointing in the direction of the star
Equator The imaginary line that runs around the middle of Earth. This is where the most direct sunlight hits Earth.
North Pole The northern most point on Earth’s surface.
South Pole The southern most point on Earth’s surface.
Hemisphere Either the top half of the Earth (northern), or the bottom half of the Earth (southern). The two halves are divided by the equator.