Earth Science Lecture: Origin of the Universe, Solar System, and Earth

A comprehensive set of question-and-answer flashcards covering Earth science branches, Big Bang theory, cosmological evidence, alternate universe models, Solar System facts, and key historical figures.

What are the four main branches of Earth Science?

Geology, Oceanography, Meteorology, and Astronomy

What does the term "geology" literally mean?

Study of Earth

Into what two broad areas is geology divided?

Historical geology and Physical geology

What is the focus of historical geology?

Understanding Earth’s origin and its development through time

What does physical geology seek to understand?

Processes that operate beneath and upon Earth’s surface

Why is Earth called the "blue planet"?

Because more than 70 % of its surface is covered by ocean

What does oceanography study?

The composition and movement of seawater, coastal processes, seafloor topography, and marine life

What does meteorology study?

The atmosphere and the processes that produce weather and climate

What causes weather and global climates according to meteorology?

The combined effects of Earth’s motions and solar energy on the atmosphere

Why is astronomy important to Earth science?

It relates Earth to the larger universe and helps probe the origins of our environment

Give two reasons why studying Earth Science is important.

It improves forecasting of natural disasters and helps us understand forces that shape Earth (others: knowing Earth’s past, better resource use)

Approximately how old is the universe according to the Big Bang theory?

About 13.8 billion years

What is the most accepted theory for the origin and evolution of the universe?

The Big Bang Theory

Who first proposed that the universe started from a single point and is expanding?

Georges Lemaître

What key discovery did Edwin Hubble announce in 1929?

The redshift of galaxies, showing they are moving away from each other

State Hubble’s Law.

The farther away a galaxy is, the faster it is receding from Earth

Which light elements formed soon after the Big Bang?

Hydrogen and Helium (with traces of Lithium)

During which era did stars first form, shaping the universe?

The Matter Era

What percentage of the universe is composed of baryonic (ordinary) matter?

About 4.6 %

Describe the Oscillating Universe theory.

The universe alternates between periods of expansion and contraction, ending in a Big Crunch before expanding again

Give one key feature of the Steady State Theory.

Matter is continually created so the universe remains the same overall; no expansion or contraction

Why did the Steady State Theory fail?

It could not explain the observed Cosmic Microwave Background radiation

Name one common misconception about the Big Bang.

That it was an explosion in space rather than an expansion of space itself

What is the cosmic microwave background (CMB)?

Uniform, pervasive remnant heat radiation left over from the Big Bang

List three pieces of evidence supporting the Big Bang.

Universal expansion (redshift), cosmic microwave background, and abundance of light elements (others: quasars, radioactive dating, stellar evolution)

What are quasars and why are they important to cosmology?

Extremely luminous galactic cores found only at great distances, indicating an evolving universe

How does radioactive decay help determine the age of Earth and the Moon?

Radiometric dating of rocks reveals their ages, showing the Moon formed before Earth

What does observing stellar life cycles across the universe demonstrate?

Stellar formation and evolution consistent with Big Bang cosmology

Provide the mnemonic that helps remember the order of the planets.

My Very Educated Mother Just Served Us Nachos

What objects make up the Solar System?

The Sun, eight planets, asteroids, dwarf planets, meteors, and comets

Approximately when did the Solar System form?

About 4.6 billion years ago

Define the "habitable zone" around a star.

The region where conditions allow liquid water to exist on a planet’s surface

What property of background radiation confirmed Big Bang predictions?

It is evenly spread across space and matches calculated temperatures

Explain galactic redshift.

Light from galaxies is stretched to longer wavelengths as they move away, showing universal expansion

What is the "singularity" in Big Bang theory?

An initial infinitely dense, hot point from which the universe expanded

What are Population III stars?

The first generation of stars formed from primordial gas with virtually no heavy elements

Give one non-scientific creation story mentioned in the lecture.

Example: The biblical Genesis in which God creates the universe (others: Mbombo vomits stars, Purusha’s body forms cosmos)

What are the three broad options for the universe’s origin posed in the lecture?

Someone made it; it made itself; or it has always existed

What major event occurred during "recombination"?

Electrons combined with nuclei to form neutral atoms, allowing photons to travel freely

How does conservation of energy relate to the CMB?

Energy from the Big Bang wasn’t destroyed; it persists as the cosmic microwave background

What is meant by the universe’s "accelerated expansion"?

The rate of cosmic expansion is increasing over time, attributed to dark energy

What is dark energy?

A mysterious form of energy thought to drive the universe’s accelerated expansion

Why is understanding Earth’s habitability significant?

It reveals conditions required for life and guides the search for life elsewhere

Which learning competency involves comparing theories of Solar System origin?

"Compare the different hypotheses explaining the origin of the Solar System."

List the major milestones from Milky Way formation to humans, in order.

Milky Way formed → Sun formed → Earth formed → single-celled life → first dinosaurs → first humans