Earth Science & Astronomy Reviewer – Vocabulary Flashcards

A comprehensive set of vocabulary flashcards covering Earth science and introductory astronomy topics discussed in the lecture notes.

Crust

Earth’s thin, solid outermost layer; divided into oceanic and continental varieties.

Oceanic Crust

Thin, dense part of Earth’s crust found beneath oceans.

Continental Crust

Thicker, less-dense portion of Earth’s crust forming the continents.

Mantle

Semi-solid rock layer beneath the crust where convection drives plate motion.

Outer Core

Liquid iron-nickel layer that generates Earth’s magnetic field.

Inner Core

Solid, hottest layer of Earth composed mainly of iron.

Plate Tectonics Theory

Concept that the lithosphere is broken into moving plates causing earthquakes, volcanoes, and mountains.

Divergent Boundary

Plate boundary where plates move apart, creating new crust and mid-ocean ridges.

Transform Boundary

Plate boundary where plates slide past each other, producing shallow earthquakes.

Convergent Boundary

Plate boundary where plates collide, destroying or uplifting crust.

Oceanic–Oceanic Convergence

One oceanic plate subducts beneath another, forming trenches and island arcs.

Oceanic–Continental Convergence

Dense oceanic plate sinks under continental plate, creating volcanic mountains and trenches.

Continental–Continental Convergence

Collision of two continental plates that pushes crust upward into folded mountains.

Compression

Stress that squeezes rocks, forming folds and reverse faults.

Tension

Stress that pulls rocks apart, producing normal faults.

Shearing

Stress that slides rocks past each other, causing strike-slip faults.

Shield Volcano

Broad, gently sloping volcano with quiet lava flows (e.g., Mauna Loa).

Cinder Cone Volcano

Small, steep volcano built from explosive eruptions of ash and cinders.

Composite Volcano

Layered volcano of alternating lava and ash; eruptions vary in intensity (e.g., Mt. Fuji).

Ring of Fire

Pacific region with frequent earthquakes and volcanic activity.

Folded Mountain

Mountain formed by compression that bends rock layers (e.g., Himalayas).

Fault-Block Mountain

Mountain created when tension causes large blocks of crust to drop or lift.

Dome Mountain

Mountain produced when magma lifts rock layers into a dome shape without erupting.

Upwarped Mountain

Mountain formed when broad areas of crust are pushed upward.

Igneous Rock

Rock formed from cooled magma or lava; may be intrusive or extrusive.

Sedimentary Rock

Rock produced by compaction and cementation of sediments; often contains fossils.

Metamorphic Rock

Rock altered by heat and pressure; can be foliated or unfoliated.

Mineral

Naturally occurring, inorganic solid with a definite chemical composition and crystal structure.

Rock Cycle

Continuous processes that transform rock types through melting, cooling, weathering, and metamorphism.

Physical Weathering

Mechanical breakdown of rock without changing composition (e.g., frost wedging).

Chemical Weathering

Decomposition of rock by chemical reactions (e.g., acid rain).

Glacier

Large, moving mass of ice that shapes landforms such as cirques.

P-Wave (Primary Wave)

Fastest seismic body wave; compressional; travels through solids, liquids, and gases.

S-Wave (Secondary Wave)

Slower seismic body wave with side-to-side motion; moves only through solids.

Surface Waves

Seismic waves that travel along Earth’s surface and cause most earthquake damage.

Love Wave

Surface wave with horizontal side-to-side motion; highly destructive.

Rayleigh Wave

Surface wave with rolling, ocean-like motion; very damaging.

Uniformitarianism

Principle stating present geologic processes explain Earth’s past.

Catastrophism

Idea that Earth has been shaped by sudden, short-lived events.

Absolute Dating

Technique that determines actual age using radioactive decay.

Carbon-14 Dating

Absolute dating method for once-living materials using radioactive carbon.

Troposphere

Lowest atmospheric layer where weather occurs; temperature decreases with height.

Stratosphere

Layer containing the ozone layer; temperature rises with altitude.

Mesosphere

Middle, coldest atmospheric layer; burns up meteors.

Thermosphere

Very hot atmospheric layer with ionosphere and auroras.

Exosphere

Outermost atmospheric layer where satellites orbit.

Weather

Short-term atmospheric conditions such as temperature, wind, and precipitation.

Climate

Long-term average weather patterns of a region.

Asteroid

Rocky object orbiting the Sun, mostly in the asteroid belt.

Comet

Icy body that develops a tail when near the Sun.

Meteoroid

Small rocky object traveling in space.

Meteor

Streak of light produced when a meteoroid enters Earth’s atmosphere.

Meteorite

Fragment of a meteoroid that survives passage through the atmosphere and hits Earth.

Core (Sun)

Central region of the Sun where nuclear fusion occurs.

Photosphere

Visible surface layer of the Sun.

Chromosphere

Reddish layer above the photosphere.

Corona

Outer atmosphere of the Sun, visible during a total solar eclipse.

Main Sequence Star

Stable phase in a star’s life where hydrogen fusion occurs.

Red Giant

Late stage of a star when it expands and cools after core hydrogen is depleted.

White Dwarf

Hot, dense stellar remnant left after a low-mass star sheds its outer layers.

Supernova

Explosive death of a massive star, creating heavy elements.

Neutron Star

Dense stellar remnant composed mostly of neutrons after a supernova.

Black Hole

Region of space with gravitational pull so strong that not even light escapes.

Big Bang Theory

Model stating the universe began from a rapid expansion of extremely dense matter and energy.

Steady State Theory

Hypothesis that the universe remains constant with continuous matter creation.

Oscillating Universe Theory

Idea that the universe alternately expands and contracts in cycles.

New Moon

Moon phase when the Sun-lit side faces away from Earth.

Full Moon

Phase when the entire Sun-lit side of the Moon is visible from Earth.

Solar Eclipse

Event where the Moon blocks the Sun during a New Moon.

Lunar Eclipse

Event where Earth’s shadow falls on the Moon during a Full Moon.

Spring Tide

Highest tidal range occurring when Sun, Moon, and Earth are aligned.

Neap Tide

Lowest tidal range occurring when the Sun and Moon form a right angle with Earth.