Edwin Hubble US astronomer

Hubble telescope deep field image of ancient galaxies

Redshift explained - this is an example of the Doppler Effect best observed with sound changing pitch as a vehicle travels towards you and then passes you by. The pitch is first too high and then too low.

Galaxies redshift velocity plotted against distance from Earth. The further away galaxies are the faster they are speeding away from us.

Hubble found the age of the universe to be 13.7 billion years old.

This is the time it would take the galaxies to have to have spread apart to where they are now.

Cosmic microwave background radiation
WMAP satellite image from 2008

This is the heat left over from the Big Bang and represents a temperature of about 3 degrees Celcius or that space is -270 degree Celcius 3 degrees above absolute zero.