Earth & Space Science – Regents Review Vocabulary

Vocabulary flashcards covering key Regents Earth & Space Science review concepts, from astronomy to weather, geology, and mapping.

Density

The mass of a substance per unit volume, usually expressed in g ⁄ cm³.

Porosity

The percentage of a material’s total volume that is pore space and can hold water or air.

Permeability

The ability of a material to transmit fluids; how easily water can flow through pore spaces.

Capillarity

Upward movement of water through tiny pore spaces due to surface tension; strongest in small particles.

Equinox

Either of two days (≈ Mar 21, Sep 23) when day and night are equal and the Sun is over the equator.

Solstice

Either of two days (≈ Jun 21, Dec 21) marking the Sun’s greatest angular distance north or south of the equator.

Vernal Equinox

March 21; first day of spring in the Northern Hemisphere.

Autumnal Equinox

September 23; first day of fall in the Northern Hemisphere.

Summer Solstice

June 21; longest day in the Northern Hemisphere, Sun’s noon altitude highest.

Winter Solstice

December 21; shortest day in the Northern Hemisphere, Sun’s noon altitude lowest.

Zenith

The point on the celestial sphere directly above an observer.

Polaris

The North Star; its altitude equals the observer’s latitude in the Northern Hemisphere.

Angle of Insolation

The angle at which sunlight strikes Earth’s surface; higher angle means more intense energy.

Station Model

Standardized symbol showing weather data (temp, dew point, pressure, wind, clouds, weather) for a location.

Sea-Level Pressure

Air pressure adjusted to sea level; plotted as a three-digit number on a station model.

Orographic Lifting

Rise of air over a mountain barrier causing cooling, condensation, and precipitation on the windward side.

Windward Side

Side of a mountain facing incoming wind; cool and wet due to rising air.

Leeward Side

Side of a mountain sheltered from wind; warm and dry as descending air compresses.

Dew Point

Temperature at which air becomes saturated and condensation begins.

Convection

Transfer of heat by movement within fluids where warmer, less-dense material rises and cooler sinks.

Cyclic Event

A phenomenon that repeats in a regular pattern, such as tides or moon phases.

Feedback Loop

Process where a change triggers actions that either amplify (positive) or reduce (negative) that change.

Index Fossil

Fossil of an organism that lived for a short time but had wide geographic distribution, used for correlation.

Unconformity

A gap in the rock record caused by erosion or non-deposition.

High-Pressure System

Area with sinking air, clockwise outward winds, clear skies, and dry weather.

Low-Pressure System

Area with rising air, counterclockwise inward winds, clouds, and precipitation.

Ocean Current

Large stream of seawater that moves through the oceans, classified as warm or cold.

Time Zone

15°-wide longitudinal belt where local time differs by one hour from adjacent zones.

Westerlies

Prevailing winds between 30° and 60° latitude that blow from the west and move weather systems eastward in the U.S.

mT Air Mass

Maritime Tropical air; warm, humid air originating over warm oceans (e.g., Gulf of Mexico).

cP Air Mass

Continental Polar air; cold, dry air forming over northern land areas (e.g., Canada).

Spring Tide

Tide with the greatest range, occurring at new and full moon when Sun, Earth, and Moon are aligned.

Neap Tide

Tide with the smallest range, occurring at first and third quarter moon when Sun and Moon are at right angles.

Solar Eclipse

Event when the Moon passes between Earth and Sun, casting a shadow on Earth (new-moon position).

Lunar Eclipse

Event when Earth’s shadow falls on the full Moon.

Phase of the Moon

The appearance of the illuminated portion of the Moon as seen from Earth, caused by the Moon’s revolution.

Primary (P) Wave

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

Secondary (S) Wave

Slower seismic wave; shear; travels only through solids, producing a shadow zone beyond the outer core.

Seismic Shadow Zone

Area on Earth receiving no direct P or S waves because of refraction and absorption in the core.

RECC

Rise, Expand, Cool, Condense – sequence of processes forming clouds.

Divergent Boundary

Plate boundary where tectonic plates move apart, producing mid-ocean ridges and rift valleys.

Convergent Boundary

Plate boundary where plates collide, forming trenches, mountains, and subduction zones.

Subduction

Process where one plate sinks beneath another into the mantle at a convergent boundary.

Mid-Ocean Ridge

Undersea mountain chain formed at divergent boundaries by upwelling magma.

Redshift

Shift of spectral lines toward longer wavelengths indicating an object is moving away.

Big Bang Theory

Scientific explanation for the origin of the universe about 13.8 billion years ago from an initial expansion.

Electromagnetic Spectrum

Range of all electromagnetic waves ordered by wavelength and frequency, from radio to gamma rays.

Greenhouse Effect

Warming of Earth’s surface as atmospheric gases absorb and re-radiate infrared energy.

Relative Humidity

Ratio of water vapor in the air to the maximum it can hold at that temperature, expressed as a percent.

Saturation

Condition when air holds all the water vapor it can at a given temperature (RH = 100%).

Half-Life

Time required for half of a radioactive isotope in a sample to decay.

Radioactive Decay

Spontaneous transformation of an unstable nucleus into a more stable one, releasing particles or energy.

Carbon-14 Dating

Radiometric method for determining age of recent organic remains up to ~50,000 years.

Chemical Weathering

Breakdown of rock through chemical reactions, dominant in warm, humid climates.

Physical Weathering

Mechanical breakdown of rock into smaller pieces without changing composition.

Frost Action

Physical weathering where water freezes in cracks, expands, and breaks rock apart.

Oxidation

Chemical weathering process where oxygen reacts with minerals (e.g., rusting of iron).

Altitude of Polaris

Angle of Polaris above the horizon, equal to observer’s latitude in the Northern Hemisphere.

Solar Noon

Time of day when the Sun reaches its highest altitude in the sky for a given location.

Main Sequence Star

Stable star fusing hydrogen in its core; most stars, including the Sun, fall on this band.

Giant Star

Luminous, cool star with large radius, evolved from a main-sequence star.

Red Dwarf

Small, cool, low-mass main-sequence star with very long life span.

Nuclear Fusion

Process powering stars where light nuclei combine to form heavier nuclei, releasing energy.

Luminosity

Total energy a star emits per second compared with the Sun; plotted on an H-R diagram.

Quartz

Hard (7), non-metallic mineral with conchoidal fracture, SiO₂, glassy luster.

Halite

Soft (2-2.5), non-metallic mineral with cubic cleavage, NaCl, tastes salty.

Cleavage

Tendency of a mineral to break along flat planes of weakness.

Fracture

Irregular or curved breakage surface of a mineral lacking cleavage.

Mafic Composition

Dark-colored igneous composition rich in magnesium and iron minerals like pyroxene and olivine.

Felsic Composition

Light-colored igneous composition rich in silica, potassium feldspar, and quartz.

Intrusive Igneous Rock

Igneous rock that crystallized slowly beneath Earth’s surface, forming large crystals.

Extrusive Igneous Rock

Igneous rock that cooled quickly at or near the surface, forming small or no crystals.

Recrystallization

Solid-state change of minerals into larger or new minerals under heat and pressure in metamorphism.

Lithification

Process transforming sediments into sedimentary rock by compaction and cementation.

Sediment

Loose particles created by weathering and erosion of rock, or precipitation of minerals.

Metamorphic Rock

Rock formed when existing rock is changed by heat, pressure, and/or chemically active fluids.

Igneous Rock

Rock formed by the cooling and solidification of magma or lava.

Eccentricity

Numerical measure (0–1) of how elliptical an orbit is; 0 = circle, 1 = line.

Elliptical Orbit

Oval-shaped path of a planet around the Sun, described by its eccentricity.

Specific Heat

Amount of energy needed to raise the temperature of 1 g of a substance by 1 °C.

Coriolis Effect

Apparent deflection of moving objects due to Earth’s rotation; right in N. Hemisphere, left in S. Hemisphere.

Troposphere

Lowest layer of the atmosphere where almost all weather occurs.

Meander

Broad curve in a river channel formed by lateral erosion and deposition.

Cut Bank

Outside curve of a meander where erosion is greatest and water velocity highest.

Point Bar

Inside curve of a meander where deposition occurs and velocity is lowest.

Delta

Triangular deposit of sediments at a river mouth where velocity decreases abruptly.

Glacier Striation

Parallel scratches in bedrock created by rocks embedded in moving ice.

Drumlin

Streamlined hill of glacial till indicating direction of ice movement.

Moraine

Ridge or mound of unsorted till deposited directly by a glacier.

Till

Unsorted, unlayered sediment deposited by glacial ice.

Abrasion

Physical weathering or erosion by grinding action of particles carried by wind, water, or ice.

Capillary Action

Movement of water upward in small pores against gravity due to adhesion and cohesion forces.

Gradient

Rate of change in elevation between two points; slope.

Contour Line

Line on a map connecting points of equal elevation.

V-Shaped Contour

Contour lines that bend upstream, indicating a river valley and direction of flow.

Visibility

Greatest horizontal distance one can see and identify objects; plotted on station models.