Scientists discovered that there are microwavesmicrowaves: Electromagnetic radiation with a frequency between that of visible light and radio waves. coming from every direction in space: this is called the cosmic microwave background radiation, or CMBR for short.
The CMBR comes from radiation created at the beginning of the universe. The Big Bang theory is the only theory at the moment that can explain the presence of the CMBR.
|The light from other galaxies is red-shifted.||The other galaxies are moving away from us.|
|The further away a galaxy is, the more its light is red-shifted.||The most likely explanation is that the whole universe is expanding. This supports the theory that the start of the universe could have been from a single explosion.|
|The Cosmic Microwave Background Radiation, CMBR, exists.||The relatively uniform background radiation is the remains of energy created just after the Big Bang.|