Cosmological Discoveries: The Universe, Big Bang, Expansion, and Red Shift Analysis

The Universe By: Derek Stahr

The Big Bang The universe is believed to be created by the Big Bang. The Big Bang is a theory by scientists who think that the universe was created by a small area of space exploding or expanding very quickly into the massive universe we live in today around 13.7 billion years ago. There are many other theories out there but most believe that the Big Bang was how the universe was made.

Cosmological Background Radiation Arno Penzias and Robert Wilson (two American astronomers) discovered something that aided in the evidence of the Big Bang. In 1963 the two of them were monitoring microwave radiation and they kept hearing some background noise. After adjusting the antenna several times nothing happened. They determined that it was cosmological background radiation left over from the Big Bang.

Edwin Hubble The universe is still expanding but not at such a rapid pace like the Big Bang. Edwin Hubble discovered this while observing some galaxies. He noticed them slowly moving away from each other. He determined that the galaxies were not just moving away from each other but instead the universe was expanding and therefore the galaxies were getting farther apart. Edwin Hubble also predicted that the positions the galaxies are in now were not there originally and over time have moved from their original spot to the spot we see them in now. Edwin Hubble discovered that using the red shift analysis.

The Red Shift Analysis and Electromagnetic Waves The red shift analysis is electromagnetic waves and spectral patterns. Electromagnetic waves is electromagnetic radiation which emits waves of energy. Stars and galaxies emit radio waves, light waves and x rays. Spectral patterns is a white light the splits off into different strips of rainbow colours. To see these colours the white light would have to go through a prism. Each different colour from the white light represents different wavelengths. White light from galaxies and stars are collected by astronomers who will then proceed to divide the light into separate spectral patterns. A spectroscope is a device that acts like a prism to separate the light into the different strips of spectra so you can measure the wavelengths.

Cosmological Red Shift The cosmological red shift is the light that is from a far away galaxy that has travelled for a long time to get to earth where we can see it through telescopes. Edwin Hubble saw the red light from the galaxies he was observing. The light is red because the wavelengths are becoming even longer. Red shifting means that something is moving away from us, so that means all the galaxies we see that are red, are moving away from us. When astronomers figured this out they deciphered that the universe was expanding. Cosmological red shift became good evidence of how the formation of the universe was at the beginning.

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