What is red-shift?
The time when a star moves from the main sequence to be a red giant
The red filter used by astronomers to analyse the light from distant stars
The increase in wavelength of light from a distant galaxy moving away from Earth
How many galaxies show a red-shift?
Zero
Only a few of the most distant galaxies
Nearly all galaxies
What does a larger red-shift indicate?
The galaxy has more stars
The galaxy is moving away faster
The star is about to explode in a supernova
More distant galaxies show more red-shift. Which major theory does this support?
Theory of stellar evolution
The existence of galaxy clusters
The Big Bang theory
What is the basic idea of the Big Bang theory?
The Universe expanded from a single tiny point, starting about 13.8 billion years ago
The Universe will end in a giant dark energy explosion
The Solar System began when a protostar started nuclear fusion reactions
What feature is believed to be the thinly spread remains of energy released in the Big Bang?
Red-shift
Light energy
Cosmic microwave background radiation
Why do scientists believe in the Big Bang theory?
Its predictions are supported by observations
It was one of the first scientific ideas to explain the beginning of the Universe
They can see it happening in supernova explosions
Observations of which kind of star have suggested that the expansion of the Universe is getting faster?
The Sun
Supernovae
Black holes
What have scientists suggested is causing the Universe to expand faster?
Dark matter
Dark energy
Antimatter
What percentage of the Universe is thought to be dark matter?
5 per cent
27 per cent
68 per cent