The Big Bang Theory

Composition of Early Universe

75% Hydrogen and 25% Helium Evidence for the Big Bang because current measurements match with the predicted composition of the universe.

Doppler Effect

A change in sound frequency caused by the motion of the source moving toward or away from the observer.

Planetary system

A set of non-stellar objects (planets) in space that are bound together by gravity and orbit a star.

Red Shift

A shift toward longer wavelengths of the spectrum. The shift is caused by the object, which is emitting the waves, moving away from the earth. All stars and galaxies are moving away from earth--Evidence of The Big Bang Theory (Hubble's Law)

Penzias and Wilson

Accidentally discovered the Cosmic Microwave Background Radiation in 1963 after noticing a constant background noise in their 20-foot horn shaped antenna which was designed to be part of a satellite transmission system. They won the Nobel Prize in Physics in 1978 for their discovery.

Universe

All existing matter, energy, and space

Edwin Hubble

Discovered many things one of which is that galaxies are moving away from us and those that are farthest away are moving the fastest

Wavelength

Distance from one point on a wave to the same point on another wave

Hubbles Law

Evidence of the Big Bang Theory proves that the universe is expanding. The farther a galaxy is, the faster it moves away from us.

First two elements created

Evidence of the Big Bang Theory. Hydrogen and Helium because they are the simplest, lightest elements with the least number of protons, neutrons, electrons.

Cosmic Microwave Background Radiation

Evidence of the Big Bang Theory. Left over heat energy from the Big Bang is observable at all points in space. The energy started as light but has shifted to microwaves and radio waves due to the continual expansion of the universe.

Galaxy

Groups of billions of stars and the planets that orbit them (the stars)

Reasoning that connects Cosmic Background Radiation to the Big Bang Theory

Microwaves and radio waves are present throughout the universe, even in areas where there appears to be no galaxies. An explosion whose waves of energy have traveled a great distance would create this occurrence. The Big Bang is the only way to explain these waves being found EVERYWHERE.

Reasoning that connects red shift to the Big Bang Theory

Objects that are moving away from a point emit a wavelength that gets stretched. The farther the object is, the more the wavelength is shifted. Galaxies that are moving away from Earth emit wavelengths that are red shifted. This red shift would mean that these galaxies (and Earth) were once closer together and thus something like the Big Bang spread them apart.

Reasoning that supports Hubble's Law

Objects that are moving away from a stationary point emit light whose wavelengths get stretched toward the red end of the spectrum. The galaxies the Hubble observed are emitting light that is red shifted thus they must be moving away from Earth.

Visible light

Small part of the electromagnetic spectrum that can be seen by the human eye

Big Bang Theory

The idea that all matter and energy was concentrated into an infinitely small, hot, dense region. Then, a violent expansion occurred that created light. Before this expansion there was nothing.

Singularity

The infinitely small, dense space that all matter and energy in the universe existed before the Big Bang

Frequency

The number of waves that pass a point in a certain amount of time

Gravity and Momentum

Two forces that will determine the outcome of the universe

How did atoms form?

Universe had to cool, electrons could then slow down and join nuclei (protons and neutrons) to form a complete atom/element. First elements were hydrogen and helium (simplest).

Dark Matter

Unseen and unidentified matter that is evident by its gravitational pull on stars in the galaxies.

Absorption Spectra

Visible light that is broken into its colors except for those colors that are absorbed by certain elements. The absorbed areas come across as black or white lines.

Flat Universe

expansion slows so much it seems to have stopped

Expansion

the action of becoming larger or more extensive.

Open Universe

the expansion continues and never stops

Closed Universe

the expansion stops and becomes a contraciton

Age of Universe

~13.7 billion years old