Big Bang Theory
By: Aubrey Phillips
How did the Universe get here anyway?
Scientists believe that the universe began with an enormous explosion of light and energy, which we now call the Big Bang Theory. This was the start to everything that exists. The beginning of the universe, and even the start of time itself.
What is the Big Bang Theory?
About 13.7 billion years ago all matter was compacted into a very small and dense ball, and intense heat. Suddenly, it began to expand and the universe came into existence.
EVIDENCE OF THE BIG BANG THEORY:
When the light from a galaxy that is moving away from you is observed, the wavelength of the light looks longer, so it moves towards the red end of the spectrum. This is called red shift.
Cosmic Background Microwave Radiation
Another piece of evidence that supports the Big Bang Theory is Cosmic Background Microwave Radiation. This is the thermal radiation left over from the Big Bang.
In 1929, Edwin Hubble announced that the galaxies seemed to be moving away from us. This was observed as a redshift of a galaxy's spectrum. The farther a galaxy, the faster it is moving away from Earth.
How We Know The Big Bang Actually Happened
How the universe has changed since the Big Bang
Although the universe has cooled down since the Big Bang, it is still expanding to this day. Many galaxies were created, and are being created. Stars, are being made everyday.