Scientists have observed that the light emitted from faraway galaxies is shifted toward the red on the electromagnetic spectrum compared to similar galaxies that are closer. This is called a redshift.
How does this data support the idea that the universe began with a period of rapid expansion and is continuing to expand?
A.
The redshift indicates the age of the galaxies.
B.
The redshift indicates that the galaxies are moving away rapidly.
C.
The redshift indicates that the galaxies are getting closer together.
D.
The redshift indicates the types of matter in the galaxies.
B. The redshift indicates that the galaxies are moving away rapidly.
The redshift of light from distant galaxies is due to the Doppler effect, which is caused by the expansion of the universe. As the universe expands, galaxies move away from each other, causing the light they emit to be redshifted. This evidence supports the idea that the universe began with a period of rapid expansion and is continuing to expand.