Answer: Expansion of universe is called the red shift and the light emitted by stars and galaxies is red light.
Explanation: As the universe is expanding, the relative distance is increasing from the Earth, hence causing an increase in the wavelength.
Red shift occurs when there is increase in wavelength. Hence, the light will shift towards the red end of the visible light.
The stars and galaxies are also farther away from the Earth, hence they also have a larger wavelength and will shift the light to the red end of the visible spectra.
