Galaxies that are far away from us have spectra that are redshifted more than galaxies that are closer to us. It is thought that the reason for this is that
A) we are at the edge of the universe and moving away from the center.
B) we are at the center of an expanding universe.
C) space itself is expanding.
D) the stars in more distant galaxies are older and cooler than those nearby.

Question

Quizplus · Accepted Answer

The fact that more distant galaxies have greater redshifts suggests that space itself is expanding, and that the galaxies are moving away from us as the universe expands.

Galaxies That Are Far Away from Us Have Spectra That