Cosmic Microwave Background Radiation

Further evidence for the Big Bang comes from the discovery of cosmic microwave background radiation (CMBR).

Astronomers discovered cosmic microwave background radiation in the 1960s.

The wavelength of this radiation appears to be the same no matter where in space that it comes from and it corresponds to a temperature of about –270 °C.

It comes from all directions and from all parts of space.

Scientists believe that the continuous microwave background radiation is the remains of the heat energy from the Big Bang, spread thinly across the whole Universe.

The Big Bang is currently the only model that explains the existence of CMBR.

Prediction from Big Bang theoryEvidence observed and explanationDoes evidence support the Big Bang theory?
Galaxies should move outwards.
  • Light from stars in other galaxies is red-shifted.
  • This indicates that other galaxies are moving away from ours.
Yes
More distant galaxies should move away faster.
  • More distant galaxies have greater red-shift.
  • This indicates that more distant galaxies are moving away faster than nearer galaxies.
Yes
Heat energy left over from the Big Bang should now be thinly spread across the whole Universe.
  • CMBR is everywhere at a temperature of about -270°C.
  • CMBR is the remains of the heat energy from the Big Bang, spread thinly across the whole Universe.
Yes