Cosmology and Earth Systems Lecture Review

Comprehensive vocabulary flashcards covering Earth's subsystems, planetary characteristics, solar system formation hypotheses, and cosmological theories.

Atmosphere

The gas envelope surrounding Earth, composed of $78.1\%$ Nitrogen, $20.9\%$ Oxygen, and $0.9\%$ Argon.

Biosphere

A subsystem of Earth that includes all living organisms across land, air, and deep oceans.

Hydrosphere

The subsystem comprising all water on Earth, consisting of $97.5\%$ saltwater and $2.5\%$ freshwater.

Cryosphere

The portion of Earth's hydrosphere that consists of frozen water.

Geosphere

The subsystem involving rocks, minerals, and landforms, divided into the Crust, Mantle, and Core.

Pangaea

A supercontinent that existed between $335$ and $175$ million years ago.

Continental Drift Theory

The theory proposed by Alfred Wegener stating that continents were once joined and slowly drifted apart.

Mesosaurus and Glossopteris

Identical plant and animal fossils found on distant continents used as evidence for Continental Drift.

Terrestrial Planets

Inner planets (Mercury, Venus, Earth, Mars) made of high melting-point materials with solid surfaces and few or no moons.

Jovian Planets

Outer planets (Jupiter, Saturn, Uranus, Neptune) made of gas and ice with no solid surfaces and extensive ring systems.

Retrograde Rotation

The clockwise rotation characteristic of the planet Venus.

Olympus Mons

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

Great Red Spot

A major storm on Jupiter that has been active for over $400$ years.

Pluto's Reclassification Criterion 3

The rule established by the IAU in $2006$ that a planet must clear its orbital neighborhood of other objects.

Meteorite

A piece of space debris that survives its passage through the atmosphere and strikes the ground.

Kuiper Belt

A ring of icy and rocky bodies located past Neptune, spanning $30$ to $50\,\text{AU}$.

Oort Cloud

A spherical boundary of icy bodies that marks the outer edge of the solar system.

Buffon's Collision Theory

A $1749$ hypothesis suggesting a comet collided with the Sun to fling out debris that formed the planets.

Nebular Hypothesis

A theory by Kant and Laplace where a rotating gas cloud collapsed under gravity to form the Sun and planets.

Accretion

The process in the Solar Nebular Disk Model where particles stick together to form larger bodies.

Differentiation

The process where the densest elements sink to the cores of forming planets while lighter elements remain on the outer boundaries.

Goldilocks Zone

The habitable zone around a star where the distance is ideal for water to remain in liquid form.

Red Shift

The phenomenon observed by Edwin Hubble where light from distant galaxies shifts toward the red spectrum, proving the universe is expanding.

Nous

The 'cosmic mind' identified by the philosopher Anaxagoras as the ordering force of the universe.

Demiurge

The divine craftsman described by Plato who built the universe using eternal Forms and mathematics.

Monads

Interconnected immaterial substances guided by pre-established harmony in the philosophy of Leibniz.

Big Bang Theory

The prevailing cosmological model proposed by Georges Lemaître where the universe expanded from a hot, dense singularity.

Steady State Theory

The theory by Fred Hoyle suggesting the universe is eternal and static, with matter continuously created to maintain density.

Oscillating Theory

The model favored by Einstein where the universe goes through infinite cycles of 'Big Bang' expansion and 'Big Crunch' contraction.