大象传媒

The Universe - CCEACosmic Microwave Background Radiation

Big Bang theory explains how the Universe was formed and why it is still expanding. Space exploration uses a variety of manned spacecraft, space probes and telescopes.

Part of Combined ScienceSpace physics

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 鈥270 掳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 .

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