natural situation in which heat is retained in an atmosphere by carbon dioxide, methane, water vapor, and other gases

lowest layer of Earth's atmosphere; where weather occurs

layer above the troposphere that contains ozone

layer in the stratosphere that absorbs most of the Sun's harmful ultraviolet radiation

layer of electrically charged particles in the thermosphere that reflects radio waves

third layer of the atmosphere

an increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)

Earth's outermost layer

Earth's thickest layer; made of hot rock

the hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations

a theory stating that the earth's surface is broken into plates that move

the extremely hot and dense center of the earth which is believed to be composed of iron and nickel

the process that creates new sea floor as plates move away from each other at the mid-ocean ridges

the process early in the life of each planet whereby denser elements sank inward and lighter ones rose

vibrations that travel through Earth carrying the energy released during an earthquake

the transfer of heat as a result of a mixing of a liquid or a gas

molten mixture of rock-forming substances, gases, and water from the mantle

says the rotation of the earth along with other random currents that naturally occur in the liquid core of the earth cause it to move in an overall direction, eventually creating and keeping an electrical current going

a stream of electrically charged particles produced by the sun's corona

two concentric, donut shape regions of stable trapped charged particles that exist between the geomagnetic field near the earth

the regions of the Moon that look smooth from Earth and actually are impact basins

light colored features on the moon's surface; Mountains on the moon

fine, greyish dust and soil that covers the surface of the moon; formed by constant pounding of the surface by impacts

says the Moon formed from matter flung off the Earth because the planet was rotating extremely fast

the idea that the moon was created at a different location in the solar system and subsequently captured by earth's gravity

the idea that the moon formed simultaneously with the earth and in orbit around it

the theory that the moon was created by the impact of a planet-sized object with the earth

severe tides that occur during full and new moons

lowest tidal range occurring near the times of the first quarter and third quarter phases of the moon