Solar System & Earth's Layers Vocabulary

A set of 40 VOCABULARY-style flashcards covering the Solar System and Earth's internal structure based on the lecture notes.

Solar System

The Sun and all objects that orbit it.

MVEMJSUN

A mnemonic for the eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

Geocentrism

An Earth-centered model where Earth is at the center and, in many versions, stationary; the Sun and other bodies revolve around Earth.

Heliocentrism

A Sun-centered model where the Sun is at the center and the Earth and other planets orbit it.

Epicycle

A small circular motion used in geocentric models to explain apparent retrograde motion of planets.

Stellar Parallax

The apparent shift in position of a star due to Earth's orbit around the Sun.

Retrograde motion

The apparent backward motion of a planet as observed from Earth; explained by epicycles in geocentric models or orbital motion in heliocentric models.

Copernicus

Renaissance astronomer who proposed the heliocentric (Sun-centered) model.

Aristotle

Ancient philosopher who contributed to geocentric ideas of the cosmos.

Aether

The ancient belief in a fifth element filling space.

Planets

Large celestial bodies that orbit the Sun.

Dwarf planets

Celestial bodies that orbit the Sun, are not satellites, and have not cleared their orbits of other debris.

Geocentric theory

Earth-centered model of the cosmos.

Heliocentric theory

Sun-centered model of the cosmos.

Sun-centered system

Another term for a heliocentric solar system.

Earth-centered system

Another term for a geocentric solar system.

Exosphere

Outermost layer of the Earth's atmosphere, blending into space.

Exobase

Lower boundary between the exosphere and the thermosphere.

Thermosphere

Upper atmospheric layer with very high temperatures; contains the start of outer space.

Kármán line

The altitude (~100 km) marking the boundary between the atmosphere and outer space.

Ozone layer

Region in the stratosphere with high ozone concentration that absorbs ultraviolet radiation.

Mesosphere

Layer between the stratosphere and thermosphere; temperatures range from very cold to moderately cold.

Stratosphere

Layer above the troposphere that contains the ozone layer and where temperature generally increases with altitude.

Troposphere

Lowest atmospheric layer; weather occurs here; temperature typically decreases with altitude.

Aurora

Polar lights produced by interactions between solar wind and Earth's atmosphere.

Meteors

Space rocks that burn up upon entering Earth's atmosphere.

Lithosphere

Rigid outer shell of the Earth comprising crust and uppermost mantle.

Crust

Earth’s outermost, thin, brittle layer; contains continental and oceanic crust.

Mantle

Layer beneath the crust; the largest Earth layer with upper and lower regions.

Outer Core

Liquid iron-nickel layer beneath the mantle; generates Earth's magnetic field.

Inner Core

Solid iron-nickel sphere at the center of the Earth.

Continental crust

Thicker, less dense crust, mainly composed of granite.

Oceanic crust

Thinner, more dense crust, mainly composed of basalt.

Granite

Rock type that forms most of the continental crust.

Basalt

Rock type that forms most of the oceanic crust.

Asthenosphere

Weak, ductile region of the upper mantle upon which tectonic plates move.

Convection currents

Movement of mantle rock due to heat differences that drives plate tectonics.

Moho (Mohorovicic discontinuity)

Boundary between the crust and the mantle.

Magnetic field

Earth’s magnetism generated by the flow of liquid iron in the outer core.

Iron and nickel

Primary metals composing the Earth's outer core.