Earth and Space Science Practice Flashcards

Vocabulary flashcards covering astronomy, space science, Earth's internal and atmospheric layers, weather instruments, storm types, and biogeochemical cycles.

Sun

A hot glowing ball of hydrogen and helium, a $4.5\text{ billion-year-old}$ yellow dwarf star providing the energy that sustains life on Earth at the center of our Solar system.

Solar wind

Stream of high-energy particles sent into space; causes the light that displays aurora borealis when seen from the Northern Hemisphere and aurora australis from the Southern Hemisphere.

Prominences

Solar storms that look like huge arches and may last several days.

Solar flares

Solar storms more intense than prominences that only last about $15\,\text{minutes}$.

Sunspots

Cool black storm areas on the Sun.

Corona

The uppermost part of the Sun's atmosphere, which is millions of miles thick.

Core (Sun)

The interior region of the Sun where nuclear fusion occurs.

Chromosphere

An orange-red layer of the Sun's atmosphere thousands of miles thick.

Photosphere

The lower atmosphere of the Sun, which is the part we see.

Mercury

The smallest and closest planet to the Sun, having no atmosphere.

Venus

The hottest planet in the Solar system with a core of molten iron, which rotates the slowest among all planets.

Earth

The only planet in the universe known to harbor life.

Mars

Known as the Red Planet, covered with iron-rich dust.

Jupiter

The biggest planet in the Solar system, featuring the Great Red Spot.

Saturn

A planet characterized by its prominent rings.

Uranus

An ice giant planet that orbits on its side unlike other planets.

Neptune

The windiest planet in the Solar system.

Milky Way

The galaxy that includes our solar system.

Comets

Celestial objects described as "dirty snowballs" with tails of dust and gases forced from the head by solar radiation; the tail always points away from the Sun.

Meteor

A meteoroid as it burns up in the Earth's atmosphere, commonly called a "shooting star".

Meteorite

A meteoroid that does not completely burn up and reaches the ground.

Moon

Earth's only natural satellite, which reflects light coming from the Sun.

Black Holes

Collapsed stars resulting in huge gravitational forces where even light cannot escape.

Quasars

Massive, remote celestial objects emitting remarkably large amounts of energy.

Radio Pulsars

Intermittent radio signals emitted by dying stars (neutron stars).

Asteroid belt

A region found between the orbits of Mars and Jupiter.

Tides

The regular rise and fall of sea levels caused by the gravitational pull of the Moon and Sun.

Spring tides

The strongest tides that occur when the Sun, Earth, and Moon are aligned in a straight line, causing the Sun's and Moon's gravities to add up.

Neap tides

The weakest tides that occur when the Sun, Earth, and Moon form a right angle, causing their gravities to cancel out one another.

Polaris

The North Star, located at the tip of the Little Dipper's "handle".

Sirius

The brightest star in the night sky, also known as the "Dog Star".

Proxima Centauri

The closest star to Earth, but too small to be seen in the night sky.

Alpha Centauri

The closest star to Earth that is visible in the night sky.

Ursa Major

The Big Bear constellation, which contains the Big Dipper.

Ursa Minor

The Little Bear constellation, which contains the Little Dipper.

Canis Major

The Big Dog constellation, which contains Sirius.

Canis Minor

The Little Dog constellation.

Orion

The constellation known as The Hunter.

Pegasus

The constellation known as The Winged Horse.

Crust

The thin, outermost layer of Earth where we live, consisting of continental crust and oceanic crust.

Mantle

A thick, semi-solid layer beneath the crust made of hot, flowing rock that moves slowly to drive plate tectonics.

Outer Core

A liquid layer of molten iron and nickel that generates Earth's magnetic field.

Inner Core

A solid, extremely hot sphere of iron and nickel located at Earth's center.

Troposphere

The lowest layer of Earth's atmosphere, where nearly all weather occurs and clouds appear.

Stratosphere

The layer of Earth's atmosphere where the ozone layer is located.

Mesosphere

The atmospheric layer where most meteors burn up.

Thermosphere

The atmospheric layer where high-energy X-rays and UV radiation from the Sun are absorbed.

Ionosphere

A series of regions located in parts of the mesosphere and thermosphere.

Exosphere

The "final frontier" of Earth's gaseous envelope.

Nitrogen

Gas making up $78\%$ of Earth's atmospheric composition.

Oxygen

Gas making up $21\%$ of Earth's atmospheric composition.

Argon

Gas making up $0.9\%$ of Earth's atmospheric composition.

Carbon Dioxide

Gas making up $0.04\%$ of Earth's atmospheric composition.

Barometer

A weather instrument used to measure air pressure.

Anemometer

A weather instrument used to measure wind speed.

Hygrometer

A weather instrument used to measure humidity.

Wind Vane

A weather instrument used to determine wind direction.

Rain Gauge

A weather instrument used to measure the amount of rainfall.

Thunderstorms

Storms in which clouds become electrically charged, producing lightning and thunder.

Tropical depression

A storm characterized by wind speeds up to $63\,\text{km/hr}$.

Tropical storm

A storm characterized by wind speeds ranging from $63\text{--}117\,\text{km/hr}$.

Typhoons

Storms originating in the Pacific Ocean with winds ranging from $120\text{--}350\,\text{km/hr}$.

Hurricane

Storms originating in the Atlantic Ocean with winds ranging from $120\text{--}350\,\text{km/hr}$.

Cyclone

Storms originating in the Indian Ocean with winds ranging from $120\text{--}350\,\text{km/hr}$.

Tornadoes

Small storms with winds of about $500\,\text{km/hr}$.

Percolation

The movement of water through the soil itself.

Evaporation

The process that changes liquid water into gaseous water (water vapor).

Condensation

The process of water vapor turning back into liquid water.

Precipitation

All liquid and solid water particles that fall from clouds and reach the ground.

Transpiration

Water vapor being released into the air from plants and soil.

Oxygen Cycle

An essential biogeochemical cycle that maintains the concentration and level of oxygen in the atmosphere.

Respiration

A biological process that releases energy in the presence of oxygen.

Decomposing

The decay process occurring when plants and animals die, which uses up oxygen and releases carbon dioxide into the air.

Rusting

Also called oxidation, a process that causes metals to rust and uses up oxygen.

Combustion

The process by which fire is generated requiring oxygen, heat, and fuel; it consumes oxygen and releases carbon dioxide.