Question

how do changes in light wavelengths support the most widely accepted ideas about the universe? a. galaxies are moving toward earth, as shown by the shift of their light toward the blue end of the spectrum. b. galaxies are moving away from earth, as shown by the shift of their light toward the red end of the spectrum. c. galaxies are moving away from earth, as shown by the shift of their light toward the blue end of the spectrum. d. galaxies are moving toward earth, as shown by the shift of their light toward the red end of the spectrum.

Explanation:

The Doppler - effect for light shows that a redshift (shift of light towards the red - end of the spectrum) indicates that the source of light (galaxies) is moving away from the observer (Earth). This supports the idea of the expanding universe, which is the most widely - accepted view. A blueshift would mean the galaxies are moving towards Earth.

Answer:

B. Galaxies are moving away from Earth, as shown by the shift of their light toward the red end of the spectrum.