Theories of the Universe Review

Formation of the Universe & Solar System

The Big Bang Theory

• 13.7 billion years ago

• States that the universe began at a singularity (a hot, small, dense force) and started rapidly expanding

• Hubble observed that galaxies are moving further away from one another --> The universe is constantly expanding --> "Hubble's Law"

Evidence?

• Galaxies are constantly moving away (expanding)

• Cosmic Background Radiation, the afterglow of the Big Bang, can be observed

• Dark energy (mass --> gravity --> slows)

Multiple Choice

How long ago did the Big Bang occur?

• 4.6 million years ago

• 4.6 billion years ago

• 13.7 million years ago

• 13.7 billion years ago

Multiple Choice

Galaxies are...

• getting closer to one another

• getting further apart from one another

• remaining the same distance from one another

Geocentric vs Heliocentric

Theories of the Universe

Ptolemy

Ptolemy was an astronomer and mathematician who further developed the geocentric theory through mathematical detail.

It would later become known as the Ptolemaic Theory.

Multiple Select

The Ptolemaic Theory is based on which theory?

• Geocentric

• Heliocentric

Copernicus

•  Nicolaus Copernicus was a great polymath or Renaissance man.

• His main idea was that our world is heliocentric (helios = sun).

• His theory was that the sun is in the middle of the solar system, and the planets go around it.

Multiple Choice

I formed the Heliocentric Model which positioned the Sun at the center of the Universe, with other planets orbiting around it.

• Aristotle

• Galileo

• Copernicus

• Ptolemy

Galileo

Galileo has been called the founder of modern science. He was one of the first people to examine the heavens with a telescope.

Galileo DID NOT agree with Ptolemy. He felt that Copernicus had a better idea and used his telescope to prove the truth in the Heliocentric Theory.

Multiple Choice

Which theory did Galileo believe in?

• Heliocentric

• Geocentric

Geocentric Theory

• The Earth is the center of the solar system.

• The moon, the planets, the sun, and the stars all rotate around the earth in circular orbits.

• The Earth stays still.

• The sun is between Venus and Mars.

Heliocentric Theory

• The Sun is the center of the Universe.

• The Earth, planets, and stars revolve around the Sun.

• The earth revolves on its own axis

Multiple Select

Which has the Sun as the center of the Universe?

• Heliocentric

• Geocentric

Multiple Select

Which theory has the Earth as the center?

• Heliocentric

• Geocentric