Origin of the Universe

Origin of the Universe

Origin and Age of the Universe

Humans have observed celestial objects for thousands of years contemplating their

place in the universe.

Celestial objects are objects outside of Earth’s atmosphere including stars, planets, galaxies, etc…

The universe is everything that exists in any place – matter and energy alike.

It is estimated that the Universe is between 10 – 13.7 billion years old.

One theory explaining the origin

of the Universe is known as the Big

Bang Theory.

The Big Bang Theory

The Big Bang Theory states that all matter and energy started out in a

concentrated form in a small area. For reasons still debated, this concentrated form of matter/energy exploded leading

to a series of changes:

1. After the explosion, all matter began to organize into subatomic particles (protons/electrons) and small atoms (hydrogen and helium).

2. Within one billion years after the explosion, matter (atoms) became organized into celestial bodies.

3. These new celestial bodies developed gravitational fields. Stars and solar systems became grouped within these fields.

From the moment of the Big Bang, the universe continues to expand in all

directions – even today!

Evidence for the Big Bang Theory

1. Energy created by the Big Bang is still evident in the form of microwaves – long wavelength background radiation emitting from all parts of the universe.

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Evidence for the Big Bang Theory

2. The shifting of characteristic wavelengths (colored lines) due to the Doppler effect.

The blue end of the colored light spectrum indicates shorter wavelengths = celestial objects are moving closer to the Earth.

The red end of the colored light spectrum indicates longer wavelengths = celestial objects are moving away from the Earth.

The Doppler effect is a phenomena that illustrates the shifting wavelengths of electromagnetic energy from objects moving in an expanding universe.

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The Doppler Effect

As the motorcycle moves closer to “Person A” the sound waves from the motorcycle compress (wavelengths

decrease) – an increase in sound. For “Person B” the sound waves are

spread out (wavelengths increase) and there is a decrease in sound.

Person B Person A

As the universe continues to expand from the Big

Bang, the electromagnetic radiation of celestial objects that are closest to the Earth

have smaller wavelengths (blue shift) than those that are moving away from the Earth (long

wavelength – red shift).

wavelength wavelength

Spectral Evidence of The Doppler Effect

Spectral lines will shift toward the red end of the spectrum when the object emitting energy is moving away from Earth.

A spectrometer is an instrument that will measure properties of light emitted from an element. Visible

light can broken down into the colored spectrum

Each element produces a

unique spectrogram – a series of black bands

(spectral lines) placed across the

colored spectrum.

Spectral lines appear when

specific wavelengths on light are absorbed.

Spectral lines will shift toward the blue end of the spectrum when the object emitting energy is moving towards Earth.