Flashcards Comprehensive Earth and Space Science: Hypotheses, Layers, and Celestial Mechanics

Hypothesis

A proposed, testable explanation for an observation.

Observations

Information gathered directly through the senses or scientific instruments.

Theory

A well-tested, widely accepted explanation that unifies many observations.

Paradigm

A dominant worldview or fundamental framework within a scientific discipline.

Geology

The study of the Earth, its materials, and the processes acting upon them.

Meteorology

The study of the atmosphere and the processes that produce weather and climate.

Astronomy

The study of the universe, providing context for Earth's place in the solar system.

Oceanography

The scientific study of the oceans, including marine life, currents, and ocean floor topography.

Hydrosphere

The dynamic mass of water on Earth (oceans, lakes, rivers, glaciers, groundwater).

Biosphere

All life on Earth and the physical environment with which it interacts.

Atmosphere

The thin, gaseous envelope surrounding Earth that provides the air we breathe and protects us from solar radiation.

Geosphere

The solid Earth, extending from the surface to the center of the planet.

Compositional Layers

Earth's layers defined by their chemical makeup: Crust, Mantle, and Core.

Crust

Earth's thin, rocky outer skin.

Mantle

The solid, rocky shell below the crust containing mostly silicate minerals.

Core

Earth's dense innermost layer, composed mostly of an iron-nickel alloy.

Functional Layers

Earth's layers defined by physical properties (solid, liquid, rigid, or plastic).

Lithosphere

The rigid, outermost functional layer consisting of the crust and the uppermost mantle.

Asthenosphere

The weak, plastic layer of the mantle located directly beneath the lithosphere.

Geologic Plate

A large, rigid slab of the lithosphere that moves continuously over the asthenosphere.

System

A group of interacting, independent parts that form a complex whole.

Open System

A system where both energy and matter flow in and out.

Closed System

A system where energy moves in and out, but matter does not enter or leave.

Mean Solar Day

Time from one noon to the next (24 hours).

Sidereal Day

Time for one complete rotation relative to a distant star (23h 56m).

Spring Tide

Highest tidal range (Earth, Moon, and Sun align).

Neap Tide

Lowest tidal range (Moon and Sun are perpendicular).

Eclipses

Solar: Moon is between Earth and Sun (New Moon). Lunar: Earth is between Moon and Sun (Full Moon).

Phases of the Moon

Starts at New Moon -> Waxing Crescent -> First Quarter -> Waxing Gibbous -> Full Moon -> Waning Gibbous -> Third Quarter -> Waning Crescent.

Universe

Everything that exists—all space, time, matter, and energy.

Galaxy

A massive, gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.

Solar System

A star (like our Sun) and all the celestial bodies that orbit it, including planets, moons, asteroids, and comets.

Orbital Plane

The flat, disk-like imaginary surface in which a planet orbits the Sun.

Terrestrial Planets

The inner, Earth-like planets (Mercury, Venus, Earth, Mars); small, dense, rocky.

Jovian Planets

The outer, Jupiter-like planets (Jupiter, Saturn, Uranus, Neptune); large, low density, gaseous/icy.

Maria

Dark, flat, smooth regions on the Moon formed by ancient lava flows.

Highlands

Light-colored, heavily cratered, mountainous regions on the Moon.

Craters

Depressions formed by meteorite impacts.

Ejecta

The debris blasted out of a crater during an impact.

Lunar Regolith

The layer of loose, powdery, grayish soil and dust covering the Moon's surface, formed by billions of years of meteorite bombardment.

Olympus Mons

The largest volcano in the solar system, located on Mars.

Valles Marineris

A massive canyon system on Mars, far larger than Earth's Grand Canyon.

Phobos

One of the two small, potato-shaped moons of Mars.

Deimos

The other small, potato-shaped moon of Mars.

Callisto

One of Jupiter's 4 largest 'Galilean' moons; heavily cratered.

Europa

One of Jupiter's 4 largest 'Galilean' moons; has an icy crust with a liquid water ocean beneath.

Ganymede

The largest moon in the solar system; one of Jupiter's 4 largest 'Galilean' moons.

Io

One of Jupiter's 4 largest 'Galilean' moons; highly volcanic.

Titan

Saturn's largest moon; has a thick nitrogen atmosphere and liquid methane lakes.

Titania

Uranus's largest moon.

Triton

Neptune's largest moon; known for its retrograde (backward) orbit and ice volcanoes.

Dwarf Planet (Planetoid)

A celestial body that orbits the Sun and is spherical, but has not cleared its orbital neighborhood of debris (e.g., Pluto).

Charon

Pluto's largest moon; it is so massive compared to Pluto that they orbit each other like a double-planet system.

Asteroids

Small, rocky/metallic bodies primarily orbiting between Mars and Jupiter (the Asteroid Belt).

Comets

'Dirty snowballs' of ice and dust with highly elongated orbits.

Coma

The glowing head of a comet that forms as the sun vaporizes its ices.

Meteoroid

A small rock traveling in space.

Meteor

A rock burning up in Earth's atmosphere ('shooting star').

Meteorite

A rock that survives the atmosphere and hits the ground.

Meteor Shower

Occurs when Earth passes through the debris trail left behind by a comet, resulting in many meteors.