Question

Scientists' evidence for an expanding universe is called a (blueshift, yellowshift, redshift, greenshift) because the light waves emitted by stars and galaxies are shifting toward the (yellow, blue, green, red) end of the visible color spectrum.

Answer 1

Answer: Expansion of universe is called the red shift and the light emitted by stars and galaxies is red light.

Step-by-step 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.