Scientists used a model of the expanding universe to predict how fast very distant galaxies should be receding. Since 1998, observations of supernovae in very distant galaxies have shown that these galaxies are receding faster than the model predicted.
Explain how scientists should respond to these observations.
79 exam-style questions on AQA GCSE Physics 8.2 Red-shift, covering 8.2 Red-shift. Each one has a worked solution and a mark scheme showing where the marks go.